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The Anthropometric and Physiological Characteristics of Elite Male Rugby Athletes
Abstract
This is the first article to review the anthropometric and physiological characteristics required for elite rugby performance within both Rugby Union (RU) and Rugby League (RL). Anthropometric characteristics such as height and mass, and physiological characteristics such as speed and muscular strength, have previously been advocated as key discriminators of playing level within rugby. This review aimed to identify the key anthropometric and physiological properties required for elite performance in rugby, distinguishing between RU and RL, forwards and backs and competitive levels. There are differences between competitive standards such that, at the elite level, athletes are heaviest (RU forwards ~111 kg, backs ~93 kg; RL forwards ~103 kg, backs ~90 kg) with lowest % body fat (RU forwards ~15%, backs ~12%; RL forwards ~14%, backs ~11%), they have most fat-free mass and are strongest (Back squat: RU forwards ~176 kg, backs ~157 kg; RL forwards ~188 kg, backs ~ 168 kg; Bench press: RU forwards ~131 kg, backs ~118 kg; RL forwards ~122 kg, backs ~113 kg) and fastest (10 m: RU forwards ~1.87 s, backs ~1.77 s; 10 m RL forwards ~1.9 s, backs ~1.83 s). We also have unpublished data that indicate contemporary RU athletes have less body fat and are stronger and faster than the published data suggest. Regardless, well-developed speed, agility, lower-body power and strength characteristics are vital for elite performance, probably reflect both environmental (training, diet, etc.) and genetic factors, distinguish between competitive levels and are therefore important determinants of elite status in rugby.
... Rugby is considered an aerobic sport with an intermi ent activity profile of frequent changes between high-and low-intensity periods, requiring physical qualities such as endurance, speed, agility, power and flexibility [1,2]. These athletic qualities are influenced by body composition characteristics [3,4]. ...
... These athletic qualities are influenced by body composition characteristics [3,4]. The body of evidence suggests that as competitive standards rise, rugby players require higher functional body mass (BM) with a lower percentage of body fat [2]. These anthropometric characteristics and athletic aptitudes change across different season periods [5,6]. ...
... This study aimed at assessing elite rugby players' hydration and body cell mass changes throughout a whole season with two different methods (BIVA and USG) that measure similar aspects, and to check the correlation between these two methods. The main findings of the present investigation were threefold: (1) BIVA identifies hydration/body cell mass changes, while USG is not able to do so; (2) no correlation between BIVA and USG was found; and (3) it is necessary to take into account the temporality of the bioelectrical assessments in the rugby players since the values change significantly. ...
Background:
Hydration status has a direct role in sports performance. Bioelectrical Impedance Vector Analysis (BIVA) and Urine Specific Gravity (USG) are commonly used to assess hydration. The study aims to identify the sensitivity and relationship between BIVA and USG in a field sports setting.
Methods:
BIVA and USG measurements were conducted five times throughout one rugby season. 34 elite male rugby players (25.1 ± 4.4 years; 184.0 ± 7.8 cm; 99.9 ± 13.4 kg) were enrolled. Differences over time were tested using one-way repeated measures ANOVA, and Bonferroni's post-hoc test was applied in pairwise comparisons. Resistance-reactance graphs and Hotelling's T2 test were used to characterize the sample and to identify bioelectrical changes. A repeated measures correlation test was conducted for BIVA-USG associations.
Results:
Two clear trends were seen: (1) from July to September, there was a vector shortening and an increase of the phase angle (p < 0.001); and (2) from December to April, there was a vector lengthening and a decrease of the phase angle (p < 0.001). USG reported neither changes nor correlation with BIVA longitudinally (p > 0.05). Vector variations indicated a body fluid gain (especially in the intracellular compartment) and a body cell mass increase during the preseason, suggesting a physical condition and performance improvement. During the last months of the season, the kinetic was the opposite (fluid loss and decreased body cell mass).
Conclusions:
Results suggested that BIVA is sensitive to physiological changes and a better option than USG for assessing hydration changes during a rugby sports season.
... Rugby is a field-based team sport that requires qualities such as endurance, speed, agility, power, and flexibility [1][2][3]. Similar to other team sports, some of a player's abilities will predominate depending on their position in the field. Thus, in rugby players, it is essential to establish their positions as accurately as possible and design training strategies to optimise a player's competitive performance. ...
... Currently, body composition (BC) is considered a determinant of athletic performance [4]. Therefore, a BC assessment, in addition to anthropometric characteristics and somatotype, helps to (1) select the athlete, (2) determine their playing position, and (3) optimise both the personal and team performance [1][2][3]. Over the last few years, the number of studies on athletes' anthropometric characteristics, BC, and somatotype has increased. ...
... In the present study, statistically significant differences in body mass, BMI, and FM% were found depending on each player's position; the forwards presented higher values of these variables than the backs (Tables 1 and 2). These results are similar to other studies conducted on rugby players [1,[42][43][44][45]. In forward players, a higher body mass and muscle mass give them more momentum and strength when making contact, more ability to soften the impacts, and more power in scrums or rucks [1,3]. ...
Featured Application: Different BIVA modalities create new opportunities to improve the study of body composition in athletes and their sport performance. Abstract: Body composition (BC) determines strength, power, and agility in sports such as rugby. Not only is the study of morphology and BC essential to establish player positions, but it also allows the optimisation of competitive performance. The aim of this study was to analyse different BC models (anthropometry and bioelectrical impedance analysis (BIA)) in a female rugby team. Their somatotype was also compared with a bioelectrical impedance vector analysis (BIVA) graph. A cross-sectional study was carried out on 19 women (8 forwards and 11 backs). Anthropometric and BIA (50 kHz, tetrapolar electrode configuration) measurements were taken using standard protocols and BC was estimated. Somatotype was calculated using the Heath-Carter method. Classic and specific BIVA were applied. Student's t, Mann-Whitney, or Chi-squared tests were used for variable comparisons. Agreement was determined via intraclass coefficient correlations. Forwards showed a higher BMI and fat mass, but there were no differences in skeletal muscle masses. Most of the players were of an endomorphic mesomorph somatotype. Specific BIVA, but not classic BIVA, detected BC differences according to player position. Moreover, an individual's interpretation of BIVA was consistent with their somatotype. In a female rugby team, BC and morphology are different according to position. This was detected in both the somatotype and specific BIVA. The application of BIVA (classic and specific) may yet prove to be a very useful strategy for the study of BC in sports.
... Sufficient energy of high-quality foods are required to support the physical development of academy RL players (Till et al., 2017b;Brazier et al., 2018), alongside their training and match demands (Whitehead et al., 2019). Adolescence is defined as the onset of sexual maturation or puberty that occurs after childhood (i.e. years until onset of adolescence) and before adulthood (i.e. a fully ossified skeletal system, a fully functioning reproductive system or the attainment of adult stature) (World Health Organisation, 2015;Hannon, Close & Morton, 2020). ...
... While the additional requirements of organised training and competition further distinguish between adolescent athletes and non-athletes (Steen, 1996;Petrie et al., 2004;Desbrow et al., 2014). In particular, young professional RL players are required to undergo large anthropometric and body composition changes from elite scholarship (U16) to senior professional playing standards (Till et al., 2017b;Brazier et al., 2018;Gesson-Brown et al., 2020), with greater anthropometric development differentiating between players who achieved senior professional vs. academy status within the ESL (Till et al., 2016a). ...
... While 4 and 25% of professional U18 players were both taller and heavier than the 97 th growth percentiles for height (~185 cm) and BM (~88 kg) in Australia (Table 5) (Cheng et al., 2014). Together, such data suggests that developed anthropometric profiles are both selected for and developed within young professional RL playing standards (Till et al., 2017b;Brazier et al., 2018), with greater size providing a possible advantage for participation and performance in youth RL playing structures (Brewer & Davis, 1995;Gabbett et al., 2005b;Johnson et al., 2014;Hausler et al., 2016a). ...
The primary aim of this thesis was to evaluate the dietary intake, energy expenditure and energy balance of young professional male rugby league players across the season.
... Each of the two teams presents 15 players on field, divided into playing position: forwards and backs. Brazier et al. [16] identified key anthropometric (low body fat percentage) and physiological (well-developed speed, agility, lower-body power and strength) properties required for elite performance in RU. From an anthropometric point of view elite athletes are heavier with lower skinfold thicknesses and higher lean mass index (LMI) than amateur and semi-professionals; from a physiological perspective they are stronger, faster and more powerful. ...
... From an anthropometric point of view elite athletes are heavier with lower skinfold thicknesses and higher lean mass index (LMI) than amateur and semi-professionals; from a physiological perspective they are stronger, faster and more powerful. Likewise, maximal aerobic and anaerobic powers are very important but they are not recognized as key discriminators [16]. Every playing position requires specific physical demands [14]. ...
... On the contrary, there is a lack of information regarding the influence of the MCT1 gene on team sport performance and especially in RU. Considering the key physiological factors, as highlighted by Brazier [16], an elite athlete must be agile and fast. Our findings suggest that the AA genotype in MCT1 variants may confer an advantage both in agility and in speed. ...
Athletic performance is influenced by many factors such as the environment, diet, training and endurance or speed in physical effort and by genetic predisposition. Just a few studies have analyzed the impact of genotypes on physical performance in rugby. The aim of this study was to verify the modulation of genetic influence on rugby-specific physical performance. Twenty-seven elite rugby union players were involved in the study during the in-season phase. Molecular genotyping was performed for: angiotensin-converting enzyme (ACE rs4646994), alfa-actinin-3 (ACTN3 rs1815739) and monocarboxylate transporter 1 (MCT1 rs1049434) and their variants. Lean mass index (from skinfolds), lower-limb explosive power (countermovement jump), agility (505), speed (20 m), maximal aerobic power (Yo-yo intermittent recovery test level 1) and repeated sprint ability (12 × 20 m) were evaluated. In our rugby union players ACE and ACTN3 variants did not show any influence on athletic performance. MCT1 analysis showed that TT-variant players had the highest peak vertical power (p = 0.037) while the ones with the AA genotype were the fastest in both agility and sprint tests (p = 0.006 and p = 0.012, respectively). Considering the T-dominant model, the AA genotype remains the fastest in both tests (agility: p = 0.013, speed: p = 0.017). Only the MCT1 rs1049434 A allele seems to be advantageous for elite rugby union players, particularly when power and speed are required.
... Rugby requires a combination of endurance, strength, skill and speed [2]. Each position makes different physiological, technical and anthropometric demands on the player [6][7][8]; thus, the ratio of high to low intensity effort ranges from 1:6 (forwards) to 1:8 (backs) [5]. Backs spend more time in free running while forwards are frequently involved in a high number of physical collisions and tackles [9]. ...
... In this study, we found that increased weight in male and female forwards was accompanied by increased body fat and skinfold thickness, confirming the results of previous studies on male competitive rugby players [8,34,39], and now confirming the same relationship in female competitive rugby players. This characteristic body composition (heavier and fatter) in forwards could enhance scrummaging force [12] and endow advantages when competing for the ball in scrums, rucks and mauls by attenuating the transfer of forces and reducing risk of injury [6,10]. Nevertheless, the % body fat of male rugby players in this study was higher than that reported in competitive rugby players from countries that have obtained better results than Spain in international championships, such as New Zealand [33] and Australia [8]. ...
... The lower level of body fat and higher lean body mass in male backs compared with forwards reported in this study are consistent with results previously reported for Australian [8], Argentinian [7], Italian [10] and Spanish [41] competitive rugby players. This body composition endows backs with the potential to improve tackling ability [23], acceleration and speed, and enhances thermoregulation [2,11], enabling them to cover a greater distance [5], increase acceleration during dynamic phases of the match and improve their role on the field [6,40,43]. One of the novelties of this study has been to confirm that these differences between positions observed previously in competitive male rugby players [7,8,10] and in the male participants in this study are also evidenced in female competitive rugby players. ...
Different rugby positions make different demands on players. It, therefore, follows that
optimum body composition may vary according to the position played. Using anthropometry and bioimpedance analysis (BIA) to assess body composition, the present study aimed to compare the effect of sex and position on body composition variables using anthropometry and BIA methods. A total of 100 competitive rugby players (35 women and 65 men) competing in the First Spanish National League were recruited voluntarily and for convenience for this study. In the laboratory, body composition was assessed by anthropometry, following the recommendations established by
the International Society for the Advancement of Kinanthropometry (ISAK), and by direct segmental multi-frequency BIA, following the guidelines established by the Spanish Group of Kinanthropometry (GREC) of the Spanish Federation of Sports Medicine (FEMEDE). We found sex-related differences in height, weight, body mass index, and body fat (%) by anthropometry and in body lean mass (%) by DSM-BIA, in 4 of the 6 skinfolds assessed (p < 0.05). We also observed position-related differences in all the variables assessed (p < 0.05) except for lean body mass, as measured by both methods of determining body composition, and front thigh skinfold. Body composition and å6skinfolds differs according to sex and playing position, backs (16.6 � 3.8% and 92.3 � 33.9 mm,) vs. forwards (20.0 � 6.7 and 115.3 � 37.6 mm), and the muscle-adipose (meso-endomorphic somatotype) development predominated in both sexes. Thus, forwards of both sexes are taller, heavier and fatter, possibly due to the specific demands of this position. In addition, body composition measurements vary according to the method used (DSM-BIA vs. anthropometry), indicating that anthropometry is probably the best body composition assessment method.
... Los jugadores que forman la unidad de delanteros tienen asignado los números del 1-8; por otro lado, los jugadores tres cuartos están designados con números del 9-15. Los delanteros están frecuentemente involucrados en tareas de lucha física con el oponente, asegurando la posesión del balón durante la melé, el lanzamiento de costado, el "ruck" (situación de contacto en el juego abierto en la cual el balón esta en el suelo y uno o más jugadores de cada equipo sobre sus pies se agrupan alrededor de este) y el "maul" (situación de contacto en el juego abierto que se produce cuando el portador de la pelota es agarrado por un oponente y al mismo tiempo uno o más compañeros del portador de la pelota se toman a él) [2][3][4] . Ellos deben ser capaces de trasladar el balón en zonas acotadas del campo durante los ataques. ...
... Ellos deben ser capaces de trasladar el balón en zonas acotadas del campo durante los ataques. La unidad de tres cuartos, en cambio, debe asegurar la posesión del balón en los placajes y el "ruck", sin embargo, su rol primario consiste en evadir a los defensores mientras son portadores del balón en amplios espacios del campo [2][3][4] . Basado en esta descripción general del juego, los delanteros serían más lentos y fuertes que los tres cuartos, siendo los tres cuartos más veloces y ágiles 5,6 . ...
... El presentar una estatura similar entre los jugadores Sub18 y Sub20, se puede explicar porque se esperan mínimos cambios en la estatura después de los 18 años y la mayoría de los jugadores se habrán acercado a la estatura de adulto a esta edad. Por el contrario, la masa corporal se espera que continúe aumentando a medida que se intensifican las exigencias competitivas y de entrenamiento (intensificación de los programas de entrenamiento de fuerza) 4 . Es llamativo el mayor porcentaje de tejido graso y sumatoria de pliegues en la selección Sub20. ...
Resumen Introducción: La evaluación antropométrica de los deportistas es necesaria para optimizar la identificación y el desarrollo de los jugadores. Nuestro objetivo es describir las características antropométricas por posición en los jugadores de las selecciones de rugby XV Sub18 y Sub20 durante dos temporadas. Material y método: A 152 jugadores de las selecciones de rugby XV Sub18 y Sub20 de España se les midió la estatura, masa corporal, pliegues cutáneos, porcentaje de tejido graso, masa muscular esquelética (MME), masa mineral ósea (MMO) y soma-totipo durante las temporadas 2015-2016 y 2016-2017. Se calculó el promedio y la desviación estándar para cada selección, grupo y posición. Se realizó el análisis de U de Mann-Whitney para comparar entre selecciones y por grupos. Para comparar entre posiciones se utilizó la prueba de Kruskal-Wallis. Resultados: Los jugadores agrupados como delanteros presentan mayor masa corporal, estatura, porcentaje de tejido graso, MME y MMO que los tres cuartos (p <0,05). Los jugadores que ocupan la posición de piliers presentan mayor porcentaje de tejido graso (p <0,05) y los que ocupan la posición de segunda línea son los de mayor estatura (p <0,05). Conclusiones: Los jugadores de élite en España Sub20 presentan mayor masa corporal, porcentaje de tejido graso y MME que los jugadores élite de España Sub18. Los jugadores agrupados como delanteros de nivel élite en España Sub18 y Sub20 presentan mayor masa corporal, estatura, porcentaje de tejido graso, MME y MMO que los jugadores agrupados como tres cuartos. La posición con mayor masa corporal y porcentaje de tejido graso es la de piliers en los jugadores de élite de España en las categorías Sub18 y Sub20. Los jugadores de nivel élite que ocupan la posición de segundas líneas son los de mayor estatura en España en las categorías Sub18 y Sub20. Palabras clave: Antropometría. Rugby. Composición corporal. Somatotipo. Summary Background: Anthropometric evaluation of athletes is necessary to optimize talent identification and player development. The aim was to describe the anthropometric characteristics of national under-18 and under-20 rugby team by field positions in two season. Material and method: 152 players of under-18 and under-20 rugby teams were to measured mass, stature, skinfolds, percentage body fat, skeletal muscle mass, bone mineral and somatype between 2015-2016 and 2016-2017 season. Mean and standard deviation were calculated for each national team, groups and positional. The Mann-Whitney U test were performed to investigate differences between national team and by groups. The Kruskal-Wallis test was performed to investigate differences between positional. Results: The foward units were heavier, taller and had a larger percentage body fat and skeletal muscle mass than back units (p <0.05). The props had a larger percentage body fat (p <0.05) and the seconds row were taller (p <0.05). Conclusions: The elite players of under-20 in Spain are heavier and have a larger percentage body fat and skeletal muscle mass than elite players of under-18. The foward units are heavier, taller and have a larger percentage body fat, skeletal muscle mass and bone mineral tan back units. The props are heavier positional and have larger percentage body fat. The seconds row are taller positional.
... In each group, the players perform tasks specific to their position during a match. The forwards wear the numbers [1][2][3][4][5][6][7][8] , and the backs wear the numbers [9][10][11][12][13][14][15] . The forwards are frequently involved in physical clashes with the members of the opposing team, securing possession of the ball in scrums, lineouts, rucks (contact situation in open play in which the ball is on the ground, and one or more players from each team close around it while remaining on their feet) and mauls (contact situation in open play that occurs when the ball carrier is held by an opponent and one or more of the ball carrier's team mates bind onto him/her) [2][3][4] . ...
... The forwards wear the numbers [1][2][3][4][5][6][7][8] , and the backs wear the numbers [9][10][11][12][13][14][15] . The forwards are frequently involved in physical clashes with the members of the opposing team, securing possession of the ball in scrums, lineouts, rucks (contact situation in open play in which the ball is on the ground, and one or more players from each team close around it while remaining on their feet) and mauls (contact situation in open play that occurs when the ball carrier is held by an opponent and one or more of the ball carrier's team mates bind onto him/her) [2][3][4] . They need to be able to pass the ball in limited areas of the field when attacking. ...
... They need to be able to pass the ball in limited areas of the field when attacking. While the backs need to secure possession of the ball in tackles and rucks, their main role is to evade defenders while carrying it in wide open spaces on the field [2][3][4] . Based on this overview of the game, the forwards are slower and stronger than the backs, and the backs are faster and more agile 5,6 . ...
Background: Anthropometric evaluation of athletes is necessary to optimize talent identification and player development. The aim was to describe the anthropometric characteristics of national under-18 and under-20 rugby team by field positions in two season. Material and method: 152 players of under-18 and under-20 rugby teams were to measured mass, stature, skinfolds, percentage body fat, skeletal muscle mass, bone mineral and somatype between 2015-2016 and 2016-2017 season. Mean and standard deviation were calculated for each national team, groups and positional. The Mann-Whitney U test were performed to investigate differences between national team and by groups. The Kruskal-Wallis test was performed to investigate differences between positional. Results: The foward units were heavier, taller and had a larger percentage body fat and skeletal muscle mass than back units (p <0.05). The props had a larger percentage body fat (p <0.05) and the seconds row were taller (p <0.05). Conclusions: The elite players of under-20 in Spain are heavier and have a larger percentage body fat and skeletal muscle mass than elite players of under-18. The foward units are heavier, taller and have a larger percentage body fat, skeletal muscle mass and bone mineral tan back units. The props are heavier positional and have larger percentage body fat. The seconds row are taller positional.
... Playing positions can be categorized into two positional groups: forwards (props and hookers [Front row], locks [Second row], and flankers and no. 8 [Back row]); and backs (scrum half and fly-half [Half backs], centers, and wings and fullbacks) [5]. Positional differences in physical [6,7] and anthropometric qualities [8,9] have been generally explored by comparing backs and forwards. The latter have been shown to be heavier and taller [6,10], and present significantly lower jump height [10,11] and sprint speed than backs over 5-and 30-m [11] (thus suggesting that anthropometric, jump, and speed measures are discriminating factors between playing positions) [7]. ...
... Positional differences in physical [6,7] and anthropometric qualities [8,9] have been generally explored by comparing backs and forwards. The latter have been shown to be heavier and taller [6,10], and present significantly lower jump height [10,11] and sprint speed than backs over 5-and 30-m [11] (thus suggesting that anthropometric, jump, and speed measures are discriminating factors between playing positions) [7]. Moreover, forwards have been shown to generate a greater sprint momentum [SM] (i.e., a product of body mass [BM] and sprint speed) [6,12], a key aspect in rugby union [12] due to the collisional characteristic of this sport. ...
... Upon review of the literature, it is noticeable that recent rugby research has focused mainly on professional players. However, these elite athletes, are usually superior in many aspects when compared to non-elite players [4,7,20] and represent a small proportion of the playing population, with a much larger percentage being amateur athletes. As such, research on this competitive level is warranted. ...
BACKGROUND
This study examined the differences in physical and anthropometric traits between specific playing positions (i.e., forwards: front row, second row, back row; backs: half backs, centers, wings/fullbacks) in amateur rugby players and analyzed the magnitude of correlations among jump, sprint, and strength measures in forwards and backs.
METHOD
Sixty-four male rugby players were assessed in anthropometrics, a variety of vertical jumps, 10- and 30-m sprint, and strength tests (i.e., squat and bench press).
RESULTS
Front row forwards (F[Formula: see text]) demonstrated significantly higher body mass (BM) than second row (F[Formula: see text]) and back row (F[Formula: see text]) (107.4 [Formula: see text] 12.8, 99.1 [Formula: see text] 9.9 and 91.6 [Formula: see text] 7.6 kg respectively; [Formula: see text] 0.001). F[Formula: see text] showed greater absolute strength in bench press and squat, although no differences were found in relative strength. Regarding the differences in jump performance, F[Formula: see text] and F[Formula: see text] showed significantly ([Formula: see text] 0.05) and significant to non-significant ([Formula: see text] 0.042–0.078, ES [Formula: see text] 0.90–1.55) higher jumps in all tasks compared to F[Formula: see text]. Moreover, F[Formula: see text] demonstrated lower sprint times and greater maximum sprinting speed (MSS) than F[Formula: see text] ([Formula: see text] 0.01). For the backs, centers (B[Formula: see text]) were significantly heavier ([Formula: see text] 0.05) and exhibited a non-significantly moderate larger sprint momentum ([Formula: see text] 0.068, ES [Formula: see text] 0.75) compared to half backs (B[Formula: see text]). MSS values were small to moderately greater in favor of wings/fullbacks [B[Formula: see text]] ([Formula: see text] 0.188–0.059, ES [Formula: see text] 0.50–0.71). Finally, statistically significant correlations were found between drop jump (flight time) and jump height across all jump tasks, sprint times and speed for both forwards ([Formula: see text] 0.541 to 0.996, [Formula: see text] 0.001) and backs ([Formula: see text] 0.422 to 0.995, [Formula: see text] 0.05).
CONCLUSIONS
In conclusion, F[Formula: see text] demonstrated significant, small to very large differences, when compared to their specific peers, whereas the backs were more similar. Additionally, our results indicated moderate to strong associations between explosive tasks such as sprinting and jumping in both playing positions.
... The professionalisation of rugby has resulted in alterations in the physical characteristics of players [37][38][39][40]. These alterations in physical characteristics such as body mass, strength, power and speed have increased the physical demands of modern rugby, such as more tackles and rucks per match [40][41][42][43][44]. ...
... The professionalisation of rugby has resulted in alterations in the physical characteristics of players [37][38][39][40]. These alterations in physical characteristics such as body mass, strength, power and speed have increased the physical demands of modern rugby, such as more tackles and rucks per match [40][41][42][43][44]. This increased physicality has contributed to increased incidence rates of concussion in rugby [45,46]. ...
... There are many similarities in anthropometric and physiological characteristics of players in RU and RL that reflect comparable physical demands including frequent, heavy physical contact in both rugby codes [40]. Elite rugby (RU and RL) has been reported to Sports 2021, 9,19 3 of 19 have a concussion incidence of~8-28 concussions per 1000 match hours [47,48], which is lower than sports such as horse racing and boxing (13) but higher than sports such as soccer (0.4) [49][50][51]. ...
Elite rugby league and union have some of the highest reported rates of concussion (mild traumatic brain injury) in professional sport due in part to their full-contact high-velocity collision-based nature. Currently, concussions are the most commonly reported match injury during the tackle for both the ball carrier and the tackler (8–28 concussions per 1000 player match hours) and reports exist of reduced cognitive function and long-term health consequences that can end a playing career and produce continued ill health. Concussion is a complex phenotype, influenced by environmental factors and an individual’s genetic predisposition. This article reviews concussion incidence within elite rugby and addresses the biomechanics and pathophysiology of concussion and how genetic predisposition may influence incidence, severity and outcome. Associations have been reported between a variety of genetic variants and traumatic brain injury. However, little effort has been devoted to the study of genetic associations with concussion within elite rugby players. Due to a growing understanding of the molecular characteristics underpinning the pathophysiology of concussion, investigating genetic variation within elite rugby is a viable and worthy proposition. Therefore, we propose from this review that several genetic variants within or near candidate genes of interest, namely APOE, MAPT, IL6R, COMT, SLC6A4, 5-HTTLPR, DRD2, DRD4, ANKK1, BDNF and GRIN2A, warrant further study within elite rugby and other sports involving high-velocity collisions.
... Bénéficier d'une masse corporelle plus grande permet aux avants d'augmenter la force produite en mêlée (L. Quarrie and Wilson, 2000) et de générer une plus grande quantité de mouvement lors des plaquages et collisions afin de prendre le dessus sur l'adversaire (Brazier et al., 2018;Cunningham et al., 2018b). De plus, la plus grande masse corporelle des avants jouerait un rôle protecteur dans la prévention des blessures liées aux impacts (Brazier et al., 2018). ...
... Quarrie and Wilson, 2000) et de générer une plus grande quantité de mouvement lors des plaquages et collisions afin de prendre le dessus sur l'adversaire (Brazier et al., 2018;Cunningham et al., 2018b). De plus, la plus grande masse corporelle des avants jouerait un rôle protecteur dans la prévention des blessures liées aux impacts (Brazier et al., 2018). Bien que la masse corporelle soit un facteur déterminant de la performance, le ratio masse-puissance des joueurs doit être augmenté en réduisant le pourcentage de masse grasse tout en augmentant la masse musculaire. ...
... Il est rapporté dans la littérature qu'au plus le pourcentage de masse grasse est faible au plus les athlètes sont compétitifs à haut-niveau de pratique . La masse grasse plus importante chez les avants jouerait le rôle d'un « tampon » protecteur contre les impacts qu'ils subissent en plus grand nombre comparativement aux arrières (Brazier et al., 2018). Cependant, ce pourcentage impacterait négativement leur activité avec et sans ballon au cours d'un match (r = -0,17), détériorerait leur capacité à battre un adversaire sur les qualités de vitesse et d'agilité ...
Rugby union is a team sport characterized by high-intensity collisions and running efforts during games which are position-dependent. Accounting for the five different positional groups, the first part of this thesis demonstrated greater high-intensity activity in European cup when compared to the TOP14 rugby union competition with position-dependent variations in the frequency of repeated high-intensity efforts and the relative
distance of high-speed movements in forwards. A decrease in high-intensity movement parameters was observed during the first and second halves of a competitive rugby union match. Indeed, the decrease in high-intensity movements was earlier in forwards and outside backs who peaked in high-intensity accelerations between the last two periods of the game, while backs were able to maintain their high-intensity activity throughout the match. Collectively, the capacity for a player to repeat high-intensity efforts during a rugby union game varied by the level of competition and was influenced by the onset of fatigue. In this context, the second part of this thesis was to conduct a repeated-sprint training in hypoxia. Hypoxia was induced by voluntary hypoventilation at low lung volume. This training protocol has largely improved the repeated-sprint ability performance in highly-trained rugby union players after seven training sessions of hypoventilation, whereas it was unaltered in the control normoxic group. Such training demands in rugby union (characterised by repeated high-intensity efforts in dynamic (running) and static (weightlifting, fighting)) have a specific impact on left ventricular remodelling. The
last part of this thesis, using 2D-speckle-tracking resting echocardiography, demonstrated that LV hypertrophy was greater in forwards when compared to backs and to control group. Systolic function remained unchanged, but diastolic function was altered, mainly in forwards, with an increase in filling pressures and a decrease in left ventricular relaxation. Finally, left ventricular twisting was similar while rugby union players exhibited lower
apical and higher basal rotations velocities compared to controls. Collectively, this CIFRE research program provided new data in activity analysis and training methods that are widely applicable to a range of rugby union programs and data on left ventricular morphology, function and mechanics for the clinician.
... Each rugby athlete has a designated position that requires specific physical and technical characteristics (Gabbett, 2005;Mellalieu et al., 2008;Brazier et al., 2018). RU forwards are involved in more scrums, lineouts, rucks, and mauls, which demands greater height, mass, power, and strength (Duthie et al., 2006), while the backs' main role in open play requires a combination of speed, acceleration, and agility (Duthie et al., 2003), thus power and strength relative to body mass. ...
... Given the relationships described above, it is not surprising that compared to lower competitive standards, elite athletes are the heaviest (RU forwards $111 kg, backs $93 kg; RL forwards $103 kg, and backs $90 kg), have lowest % body fat (RU forwards $15%, backs $12%; RL forwards $14%, and backs $11%), have most fat-free mass, are strongest (back squat: RU forwards $176 kg, backs $157 kg; RL forwards $188 kg, backs $ 168 kg; bench press: RU forwards $131 kg, backs $118 kg; RL forwards $122 kg, and backs $113 kg), and fastest (10 m: RU forwards $1.87 s, backs $1.77 s; 10 m RL forwards $1.9 s, and backs $1.83 s) (Gabbett, 2002;Duthie et al., 2003;Gabbett, 2006;Lundy et al., 2006;Till et al., 2011;Sedeaud et al., 2012;Fuller et al., 2013;Sedeaud et al., 2013;de Lacey et al., 2014;Morehen et al., 2015;Till et al., 2017;Brazier et al., 2018). Indeed, some of those data probably underestimate the physical qualities of contemporary athletes (Brazier et al., 2018). ...
... Given the relationships described above, it is not surprising that compared to lower competitive standards, elite athletes are the heaviest (RU forwards $111 kg, backs $93 kg; RL forwards $103 kg, and backs $90 kg), have lowest % body fat (RU forwards $15%, backs $12%; RL forwards $14%, and backs $11%), have most fat-free mass, are strongest (back squat: RU forwards $176 kg, backs $157 kg; RL forwards $188 kg, backs $ 168 kg; bench press: RU forwards $131 kg, backs $118 kg; RL forwards $122 kg, and backs $113 kg), and fastest (10 m: RU forwards $1.87 s, backs $1.77 s; 10 m RL forwards $1.9 s, and backs $1.83 s) (Gabbett, 2002;Duthie et al., 2003;Gabbett, 2006;Lundy et al., 2006;Till et al., 2011;Sedeaud et al., 2012;Fuller et al., 2013;Sedeaud et al., 2013;de Lacey et al., 2014;Morehen et al., 2015;Till et al., 2017;Brazier et al., 2018). Indeed, some of those data probably underestimate the physical qualities of contemporary athletes (Brazier et al., 2018). Thus, RU and RL elite athletes have high maximal aerobic and anaerobic power, speed, agility, and muscular strength and power, as well as the underlying anthropometric features to provide those functional abilities. ...
Compared to sprint/power and endurance sports, the genetic contribution to success in sports that require a mixture of anaerobic and aerobic qualities has received relatively limited attention. This chapter evaluates research findings on the potential genetic variants influencing the team sports athletic status and the key factors for team sports performance, with particular emphasis on football (soccer) and rugby. Despite the great potential of the genetic studies in team sports and some promising progress recently made, there is very much more yet to be discovered than is understood at present. So far, only 10 genetic markers associated with team sports athlete status have been identified, and replication studies are needed to confirm those associations. In view of the foregoing, large collaborative projects with sound experimental designs (e.g. clearly defined phenotypes, consideration and control of sources of variability, and necessary replications) are needed to improve understanding in this area.
... These anthropometric characteristics are key factors in winning or keeping the ball and making tackles [36]. In addition, they play a protective role against the many injuries that can be caused by shocks and intense contact during the game [38]. Forwards are involved in 68% of the total collisions. ...
... Of note, forwards compared with backs experience significantly more tackles and collisions during match play [38,45]. These high-intensity activities during the game are associated with changes in markers of muscle damage [7]. ...
This study proposes to monitor the physical, immune and cognitive responses and adaptations of elite rugby players throughout the season based on the loads performed. Anthropometric measurements, physical fitness tests (e.g., muscle strength and power, linear and change-of-direction speed, cardiorespiratory fitness) and analyses of serum concentrations of markers of muscle damage (creatine kinase [CK] and lactate dehydrogenase [LDH]) and brain-derived neurotrophic factor (BDNF) were carried out over a sporting season (24 weeks) for 17 elite rugby players (10 forwards and 7 backs) aged 18.91 ± 0.76 years. The physical fitness test results show improvements in the performance of both forwards and backs over the season (p < 0.05), with an advantage for backs compared with forwards in most tests (p < 0.05). Muscle damage markers decreased at the end of the season compared with the baseline levels for forwards (p < 0.05). CK levels were unchanged for the backs, but there were increased LDH concentrations at the end of the season compared with baseline (p < 0.05). Serum BDNF levels decreased for the total group between the second and third sampling (p < 0.05). The muscular and physical capacities of rugby players differ according to their playing position. Immune responses and adaptations, as well as BDNF levels, vary throughout the season and depend on the physical load performed.
... Notably, each football code's specific physical demands are considerably different, likely affecting the pre-season period's length and structure. Components of fitness required for all football codes, regardless of playing position, include aerobic and anaerobic fitness, speed, agility and power (20,31,42,45). However, each code also requires specific physical components to be well developed. ...
... Generally, elite soccer athletes require speed, agility, and anaerobic and aerobic fitness due to the dynamic locomotor demands of the game (45). Rugby league and rugby union athletes, due to the generally linear and collisional nature of their code, require a relatively greater level of functional body mass with low body fat percentage, relative and absolute strength and power, as well as aerobic and anaerobic fitness (20). There is a greater emphasis on resistance training to develop such capacities, typically prescribed three to four sessions per week during the pre-season period (39). ...
Organisations governing football codes worldwide continually seek to optimise the balance between their match calendar and commercial revenue. For many competitions, the result is more matches, and consequently, increased workload and travel demands for players. However, as competitions expand, the greater volume and/or intensity of workload challenges coaches’ best practices in balancing performance with recovery and injury risk. This current perspective article aims to overview the annual training and competition calendar of professional football codes and competitions internationally. There is a vast difference in the length and structure of each component of football macrocycles, which appears dependent on the physiological capabilities required to compete in each code successfully. However, there is little research to justify the season’s structure of any football code. The importance of athlete physical and mental health is highlighted, and discussed the limitations and restrictions governing bodies implement to protect players. In conclusion, future research to improve the structure of the annual training and match calendar should incorporate a framework of both physiological and psychological components to support elite football athletes better.
... Pass and fail of this test were determined based on the p value provided from the analysis (p ≤ 0.05) with any non-normal data removed from further statistical analysis. A multivariate analysis of variance (MANOVA) was used to compare differences in running performance variables among positional groups [29] and playing half [1,14]. The dependent variables across the range of analysis were all locomotor and physical variables such as: total distance (m); running distance (m; ≥ 4.4 m s −1 ); high-speed running (m; ≥ 5.5 m s −1 ); sprint distance (≥ 7 m s −1 ); accelerations (n; ≥ 2 m s −2 ); decelerations (n; ≥ − 2 m s −2 ); and collisions (n; ≥ 4 g −1 ). ...
... These data describe in detail the position specific composition of RHIE during match-play and provide normative data that allow coaches to create specific training drills that allow players to attain locomotor and physical performances that meet or exceed the within game RHIE demands. Previously literature within rugby union has provided clarity with respect to the general movement demands of rugby union players during match-play [20,[27][28][29][30][31][32]. However, the evolution of tactical roles and known importance of RHIE within collision sports means that there is a requirement to understand these RHIE demands to better inform the rugby union training process. ...
The current investigation aimed to understand the positional profile of repeated high-intensity-effort activity (RHIE) across halves during elite rugby union match-play. Forty elite rugby union players (n = 40) were monitored across match-play during a single season. Player’s locomotor profiles were recorded using wearable microtechnology (GPS; Catapult S5, Australia). Locomotor activity was classified across total distance (m); running distance (m; ≥ 4.4 m s⁻¹); high-speed running (≥ 5.5 m s⁻¹); sprint distance (≥ 7 m s⁻¹); accelerations (≥ 2 m s⁻²); decelerations (≤ − 2 m s⁻²); and collisions (≥ 4 g). Peak velocity (m s⁻¹); total efforts (n); high-intensity efforts (HIE), repeated high-intensity efforts (RHIE), total number of RHIE bouts (n), maximal number of efforts within a RHIE bout (n) and recovery times between RHIE (s) were also recorded across match-play. Players were shown to complete 164 ± 30 HIE per game. Overall players performed 11 ± 6 RHIE bouts. The mean efforts per RHIE bout was 4 ± 1 with a maximum of 6 ± 2. RHIE positional differences were reported with back-rows completing the most total efforts when compared to all positions within the forwards (ES: 1.33–5.29; moderate–very large). Significant reductions were reported between halves for all running and repeated effort variables. The data highlight the potential consideration that RHIE should be given by coaches when preparing players for rugby union match-play. An understanding of the positional differences in RHIE can assist coaches in designing training drills that can expose players to these match-play requirements.
... These demands differ in magnitude and specificity depending on the diverse positional units of backs and forwards, and diverge further considering the individual requirements of specific positional sub-groups (15-a-side game; Quarrie, Hopkins, Anthony, & Gill, 2013;Smart, Hopkins, & Gill, 2013). While these game demands are starting to be understood in the women's game, and appear to be relatively similar to the men's game (covering similar total distances throughout 80 mins; ∼ 6000 m match À1 ) (Sheppy et al., 2019), phenotypic differences are well documented in the men's game (Brazier et al., 2018;Cahill, Lamb, Worsfold, Headey, & Murray, 2013;Deutsch, Kearney, & Rehrer, 2007;Quarrie et al., 2013;Roberts et al., 2008;Smart, Hopkins, Quarrie, & Gill, 2014); however, little is known of elite women's RU (Hene, Bassett, & Andrews, 2011;Hene & Bassett, 2013;Sheppy et al., 2019). Thus limiting our understanding of the physiological requirements. ...
... The present data in international women's rugby show that, while forwards had greater body mass compared to backs (∼ 10 kg), it did not translate into differences in lower-body net peak power (∼ 40 W difference; Tab. 1). This differs from the positional differentiation of peak power in the men's game, where forwards are substantially more powerful (∼ 400 w difference; Brazier et al., 2018;Heffernan et al., 2017). However, after controlling for mass, international women's backs had a greater relative power output and these data mirrored the men's data (Tab. ...
Rugby union (RU) is an intermittent team sport, with diverse playing positions, played internationally by both men and women. Considerable scientific attention has been devoted to men’s RU, however despite the growth in the women’s professional game, there is a significant lack of available physiological and normative data. The purpose of the present study was to investigate positional variation in countermovement jump characteristics from elite women’s RU players. Qualitative data were collected from women’s Rugby World Cup (2017) competitors (n = 86; age: 27 ± 5 years; body mass: 77.8 ± 10.6 kg; height: 1.69 ± 0.07 cm) and jump data (countermovement jumps) were collected using a 1200 Hz force platform (n = 63). Athletes were divided into positional unit (backs: n = 39 and forwards: n = 47) and by positional subgroups. Backs had greater jump height (ES = 0.72, 95%CL ± 0.50), relative power output (ES = 0.84, 95%CL ± 0.50), relative force production (ES = 0.62, 95%CL ± 0.51) and reactive strength index (RSI; ES = 0.62, 95%CL ± 0.50), compared to forwards (for all, P < 0.02). Backrows, halves and back-three players had greater relative force, relative power and jump height, compared to the front and second rows ( P < 0.03; ES > 0.70). These data could aid in programming for long-term player development in women’s RU and could have implications for “readiness” to compete at international level.
... Sportswomen who compete at comparable levels to sportsmen may have less access to sports performance support (e.g., medical and sport science), this may be a result of lower financial investment (International Working Group on Women and Sport WSI, 2007;Fink, 2015). From a performance perspective, marked differences between the sexes can be seen in anthropometric (Quarrie et al., 1995;Brazier et al., 2018;Sella et al., 2019), movement demands (Ball et al., 2019), physical performance (Sella et al., 2019;Owen et al., 2020) and physiological characteristics (Sheel, 2016). Decreased levels of skeletal muscle mass (Abe et al., 2003), lower rates of muscular fatiguability (Hicks et al., 2001), lower maximum velocity, strength and power have all been previously reported (Quarrie et al., 1995;Brazier et al., 2018;Ball et al., 2019) in females. ...
... From a performance perspective, marked differences between the sexes can be seen in anthropometric (Quarrie et al., 1995;Brazier et al., 2018;Sella et al., 2019), movement demands (Ball et al., 2019), physical performance (Sella et al., 2019;Owen et al., 2020) and physiological characteristics (Sheel, 2016). Decreased levels of skeletal muscle mass (Abe et al., 2003), lower rates of muscular fatiguability (Hicks et al., 2001), lower maximum velocity, strength and power have all been previously reported (Quarrie et al., 1995;Brazier et al., 2018;Ball et al., 2019) in females. Additionally, female athletes must consider their menstrual and oral contraceptive pill cycles which may influence athletic performance McNulty et al., 2020). ...
Female sports have recently seen a dramatic rise in participation and professionalism worldwide. Despite progress, the infrastructure and general sport science provisions in many female sports are behind their male counterparts. From a performance perspective, marked differences in physical and physiological characteristics can be seen between the sexes. Although physical preparation practices for male athletes are known, there are currently no published literature pertaining exclusively to female athletes. This information would provide invaluable data for both the researcher and practitioner alike. This survey therefore aimed to examine current practices utilized in female rugby codes (union, league, and sevens). A questionnaire assessing seasonal physical preparation practices, recovery, monitoring and sport science technology, and unique aspects in female rugby was developed. Thirty-seven physical preparation practitioners (32 males, 5 females) responded to the questionnaire. Most participants (78%) worked with national or regional/state level female athletes. Performance testing was more frequently assessed in the pre-(97%) and in-season (86%), than off-season (23%). Resistance, cardiovascular, sprint and plyometric training, and recovery sessions were all believed to be important to enhancing performance and implemented by most participants (≥ 89%). Sport science technologies were commonly (54%) utilized to inform current practice. Menstrual cycle phase was monitored by 22% of practitioners. The most frequently reported unique considerations in female rugby codes included psycho-social aspects (41%), the menstrual cycle (22%), and physical differences (22%). Practitioners working with female rugby can use the presented data to inform and develop current practices.
... Body composition, which encompasses muscle (lean mass [LM]), fat mass [FM], and bone mineral content [BMC]) in the body, plays an important role in athletes' physical attributes such as strength, speed, and power (7,14,25). By quantifying changes in body composition, practitioners can gain deeper insight into how an athlete is responding to strength and conditioning, nutritional, and sport specific interventions. ...
Russell, JL, Baker, BS, Mercer, RA, and McLean, BD. Examining the influence of season phase, age, and anthropometrics on body composition trends in NBA athletes. J Strength Cond Res XX(X): 000-000, 2024-This study aimed to describe seasonal body composition changes in NBA athletes using Dual-energy X-ray Absorptiometry (DXA) and to explore the relationship between these changes and factors such as age and anthropometrics. A retrospective analysis was conducted using 402 DXA scans from 62 professional male basketball players, obtained from one NBA team between 2012 and 2023. Seasonal phases were defined as preseason, pre all-star, post all-star, and offseason. A custom region of interest (ROI) method was used to ensure consistent scan areas for taller athletes who exceeded the DXA bed length. Linear mixed models analyzed the influence of seasonal phases, age, and height on lean mass (LM), fat mass (FM), and bone mineral content (BMC). In-season phases (pre all-star and post all-star) showed small increases in LM and decreases in FM compared with the preseason, with no significant BMC changes. Chronological age was associated with increases in LM but not FM. Taller athletes exhibited increases in LM, FM, and BMC. Significant random variance across players and seasons indicated that additional unmeasured factors might influence body composition. NBA athletes generally gain LM and lose FM during the season, with older players showing increased LM gain. The study's novel ROI method provide reliable data for athletes exceeding standard DXA limits, highlighting the importance of tailored body composition assessments in professional basketball. These findings can inform strength and conditioning, nutrition, and player development strategies across different seasonal phases and ages.
... Additionally, pre-season TEE data are available for young male rugby league players (18.36 ± 3.05 MJ·day −1 (4388 ± 729 kcal·day −1 )) (Costello et al. 2019). However, the application of these findings is limited by the anthropometric and physiological differences between the sexes (e.g., with regard to reproductive endocrinology) (Hackney et al. 2019;Brazier et al. 2020;Wohlgemuth et al. 2021;Yao et al. 2021), along with differences in match demands (Woodhouse et al. 2021) and training schedules (Hackney et al. 2019;Wohlgemuth et al. 2021). Thus, specific research is required to accurately determine the energy requirements of female rugby players, including during match-play. ...
The purpose of this study was to quantify the total energy expenditure (TEE) of international female rugby union players. Fifteen players were assessed over 14 days throughout an international multi-game tournament, which represented two consecutive one-match microcycles. Resting metabolic rate (RMR) and TEE were assessed by indirect calorimetry and doubly labelled water, respectively. Physical activity level (PAL) was estimated (TEE:RMR). Mean RMR, TEE, and PAL were 6.60 ± 0.93 MJ·day⁻¹ (1578 ± 223 kcal·day⁻¹), 13.51 ± 2.28 MJ·day⁻¹ (3229 ± 545 kcal·day⁻¹), and 2.0 ± 0.3 AU, respectively. There was no difference in TEE (13.74 ± 2.31 (3284 ± 554 kcal·day⁻¹) vs. 13.92 ± 2.10 MJ·day⁻¹ (3327 ± 502 kcal·day⁻¹); p = 0.754), or PAL (2.06 ± 0.26 AU vs. 2.09 ± 0.23 AU; p = 0.735) across microcycles, despite substantial decreases in training load (total distance: −8088 m, collisions: −20 n, training duration: −252 min). After correcting for body composition, there was no difference in TEE (13.80 ± 1.74 (3298 ± 416 adj. kcal·day⁻¹⁾ vs. 13.16 ± 1.97 (3145 ± 471 adj. kcal·day⁻¹) adj. MJ·day⁻¹, p = 0.190), RMR (6.49 ± 0.81 (1551 ± 194 adj. kcal·day⁻¹) vs. 6.73 ± 0.83 (1609 ± 198 adj. kcal·day⁻¹) adj. MJ·day⁻¹, p = 0.633) or PAL (2.15 ± 0.14 vs. 1.87 ± 0.26 AU, p = 0.090) between forwards and backs. For an injured participant (n = 1), TEE reduced by 1.7 MJ·day⁻¹ (−401 kcal·day⁻¹) from pre-injury. For participants with illness (n = 3), TEE was similar to pre-illness (+0.49 MJ·day⁻¹ (+117 kcal·day⁻¹)). The energy requirements of international female rugby players were consistent across one-match microcycles. Forwards and backs had similar adjusted energy requirements. These findings are critical to inform the dietary guidance provided to female rugby players.
... The phosphagen pathways are the predominant source of energy for allout activities up to approximately six-seconds in duration (Chamari & Padulo, 2015). Rugby specific movements such as sprinting, jumping, tackling and scrummaging all require neuromuscular activation reliant on phosphagen pathways (Brazier et al., 2018). Existing research has shown that these efforts are relevant to overall match performance, with small yet significant relationships found between sprinting speed and line breaks in professional players (Smart et al., 2014). ...
The purpose of this study was to determine relationships between traditional tests of maximal and ballistic strength, with the results of a 6 s cycle sprint (6sCS) in international level Rugby Union (Rugby) players. Thirty-three international level male Rugby players participated in the study. Each player completed the 6sCS, sprint run, standing long jump, weighted and unweighted countermovement jumps, and a 1RM squat test. Pearson’s correlations were carried out to determine relationships between absolute (PPO) and relative peak power output (relPPO) from the 6sCS with the other tests of maximal and ballistic performance for the whole population and for positional groups. For the cohort, significant correlations (p≤0.05) between relPPO and various measures of speed (r=0.63-0.73) and jump performance (r=0.48 to 0.53) were observed. In the Backs, there were large, significant relationships with weighted countermovement jump, standing long jumps, and 10 m sprint time (r=0.58 to 0.74). Large significant correlations were found with sprint and standing long jump performance in the Forwards (r=0.54 to 0.82). These significant correlations are most likely due to similarity in duration, energy system requirements, contraction types, and similarities in muscle groups recruited. Differences between position groups may reflect the physical qualities players possess to meet game demands. The study suggests that 6sCS may be a valuable addition to existing testing to evaluate maximal and ballistic intensity performancebenchmark levels of these physical capacities in elite RU players.
... 8 O consenso de dados publicados anteriormente também sugeriu que o BF% corporal, a velocidade, a agilidade, a potência muscular dos membros inferiores e a aptidão aeróbica são fatores importantes que determinam o desempenho atlético dos jogadores durante a competição. 9,10 Consequentemente, o BF% demonstrou ter uma correlação negativa com o desempenho físico em estudos anteriores. 11,12 Essa relação pode ocorrer porque o aumento de 1 kg de gordura pode aumentar a demanda aeróbica por exercício em até 14%. ...
Objetivos: Investigar a relação entre composição corporal e as características de aptidão física dos jogadores de rúgbi universitário e explorar os seus perfis físicos baseados em suas posições de jogo. Métodos: Jogadores universitários de alto nível (n = 27, idade = 21,2 ± 1,1 anos) foram agrupados em duas posições de jogo, onde avaliou-se os avançados e os recuados. Foram recolhidos dados para peso corporal (BW), altura, composição corporal (percentagem de gordura corporal [BF%] e massa corporal magra [LBM]), teste de sprint de 3 segundos (3SST), mudança de direcção de Illinois (ICOD), salto vertical (VJT), e aptidão aeróbica (VO2 max). Resultados: Os jogadores avançados apresentaram um BW, BF%, e LBM significativamente mais elevados em comparação com os jogadores recuados. Os jogadores recuados foram significativamente mais rápidos e apresentaram um VO2 máximo melhor do que os jogadores avançados. Dependendo das posições de jogo, BF% e LBM mostraram uma relação moderada a forte com desempenhos de aptidão física. Conclusão: A antropometria como a altura, BW, LBM, e VO2 max pode ser um factor que contribui para determinar as posições dos jogadores e os seus padrões de jogo apropriados no rugby union. Nível de Evidência III; Estudo Retrospectivo Comparativo.
... Maximum effort sprinting commonly occurs over short distances (,30 m) and durations (2-3 seconds) in team sports; therefore, S&C training and subsequent longitudinal research has emphasized the development of speed and acceleration over similar distances (8,31,59). Previous intervention studies have reported reductions in sprint times of 0.03-0.41 seconds across a range of athletes and distances up to 40 m, with an average percentage difference of 3-4% (2,13,14,22,23,27,37,57,58,65). ...
Murphy, A, Burgess, K, Hall, AJ, Aspe, RR, and Swinton, PA. The effects of strength and conditioning interventions on sprinting performance in team sport athletes: a systematic review and meta-analysis. J Strength Cond Res 37(8): 1692–1702, 2023—Linear sprinting is a key determinant of athletic performance within team sports. The aims of the review were to quantify and compare the effectiveness of popular strength and conditioning (S&C) training modes to improve sprint performance in team sport athletes, with additional focus on potential moderators and the relationships between improvements in physical factors (e.g., strength, power, and jump performance) and improvements in sprint performance. Inclusion was restricted to resistance, plyometric, sprint, and combined training interventions comprising team sport athletes. Multilevel, Bayesian’s meta-analysis and meta-regression models conducted with standardized mean difference effect sizes were used to investigate training modes and potential moderators. Weighted regression models conducted on shrunken estimates from initial Bayesian’s meta-analyses were used to quantify relationships between improvements in physical factors and sprint performance. Certainty of evidence was assessed using the grading of recommendations assessment development and evaluation (GRADE) approach. Similar improvements in sprint performance were obtained across training modes, with some evidence of the largest effects with resistance training ( = 0.55 [95% credible interval [CrI]: 0.36–0.78; very low certainty]). A strong moderating effect of training intensity was identified across all training modes with evidence of greater improvements in sprint performance with high-intensity training ( = 0.17 [95% CrI: 0.01–0.33; very low certainty]). Strong positive relationships were identified between improvements in all physical factors and sprint performance ( = 0.56 [95% CrI: 0.36–0.77; low certainty], = 0.80 [95% CrI: 0.50–1.0; low certainty], = 0.78 [95% CrI: 0.57–0.97; low certainty]). The findings indicate that focus on developing speed in team sport athletes should be placed on S&C training with high intensities, including the use of resisted sprint training.
... Regarding positional roles, players are generally grouped into two distinct units (i.e., forwards or backs) with each position performing specific game tasks (Delahunt et al., 2013) and presenting different physical, physiological, and anthropometric characteristics (Darrall-Jones, Roe et al., 2016;Fontana et al., 2015;Kobal et al., 2016;La Monica et al., 2016;Zabaloy et al., 2021;Zabaloy, Pareja-Blanco et al., 2020). For example, forwards are involved in more scrums, lineouts, rucks, and mauls, which demands greater height, BM, and absolute strength (i.e., irrespective of BM) to be effective, whereas backs' role of advancing into opposing territory in open play requires a combination of speed, acceleration, and agility (Brazier et al., 2020;Duthie et al., 2003;Duthie, 2006b). In terms of physical performance, Darrall-Jones, demonstrated that in English academy rugby players (U-16, U-18, and U-20) clear between-and within-age categories differences exist for sprinting characteristics, among both playing positions. ...
This study aimed to compare body composition and physical performance between U-17 and U-19 rugby players (forwards and backs), and examine the correlations among body composition, relative strength, jump, and sprint performance in both playing positions. Fifty-two male adolescent rugby players (mean ± SD: age, U-17: 16.2 ± 0.6 and U-19: 18.09 ± 0.9 years) participated in the study. Players performed anthropometric, body-composition (∑3 skinfolds [SF], body fat [BF] and lean mass [LM]), vertical jump, 30-m sprint, and squat one-repetition maximum (1RM-SQ) tests. Significant differences were observed for body mass (BM) and body composition variables among playing positions for both categories (p: 0.05 to < 0.001; ES > 0.72). U-17 forwards showed significantly different performance across all variables when compared to U-19 backs (p: 0.05 to < 0.001; ES > 1.08). Likewise, U-17 forwards showed lower relative strength (p: 0.05-0.095; ES > 1.66) and higher 30-m sprint times (p < 0.024; ES > 0.57) when compared to U-19 forwards and U-17 backs. Overall, for the backs, BM and LM were significantly associated with all performance variables (r: -0.72 to 0.50; p < 0.05). Conversely, for the forwards, BF and SF were significantly correlated with vertical jump height and sprint times (r: -0.62 to 0.52; p < 0.05). Clear differences exist between backs and forwards irrespective of the age category, whilst no differences were observed between U-17 and U-19 backs. The present results suggest that practitioners should monitor different body-composition variables due to the magnitude of associations observed with sprinting and jumping abilities.
... The anthropometric characteristics are also similar to those reported by other authors 51,17,52,50,53 , with a body mass of between 115-98 kg for FR and between 95-84 kg for BR and a height of between 190-183 cm among FR and between 182-178 cm for BR. When comparing the percentage of fat, attention must be paid to the technique and formula applied. ...
Introduction: The relation of a biological variable to body mass is typically characterized by an allometric scaling law. The purpose of this study was to evaluate the relationship between oxygen consumption (VO2max), as a parameter of aerobic exercise performance, and body composition in rugby players. Material and method: The sample included one hundred and seven males of the Spanish rugby team. Age: 25.1 ± 3.4 years; body mass (BM): 89.8 ± 11.7 kg, height: 182.4 ± 6.5 cm; 52 backs (BR) and 55 forwards (FR). Maximum oxygen consumption (VO2max, l.min-1) was measured during treadmill exercise test with progressive workload. Anthropometrical measurements were performed to estimate the fat-free mass (FFM) and muscle mass (MM). The allometric exponent “b” was determined from equation y = a * xb; where “y” is VO2max and, “x” is the corresponding mass (BM, FFM or MM) and “a” is one constant. Results: The VO2max was 4.87 ± 0.56 l.min-1, BR vs FR, 4.67 ± 0.48 l.min-1 vs 5.06 ± 0.06 l.min-1; FFM: 77.5±7.7 kg, 73.5±7 kg vs 81.3±6.3 kg; and MM: 52.9±6.5 kg, 49.6±5.6 kg vs 56.1±5.8 kg. The allometric exponents (p <0.0001; R2 = 0.4) were: 0.58 for BM (95% CI: 0.45 - 0.72); 0.71 for FFM (95% CI: 0.53 - 0.90); and 0.58 for MM (95% CI: 0.43 - 0.73). Significant differences (p <0.0001) were found BR vs FR according to their anthropometric characteristics and VO2max with respect to BM and MM without allometric scaling. While the VO2max indexed by means of allometric scaling was similar between BR and FR. Conclusions: In comparative studies, the VO2max should be expressed proportional to the 0.58 power of body mass or related to FFM in order to take into account the variability in of body composition in rugby players.
... Rugby is a full-contact, intermittent invasion sport (1). As in many invasion sports, the aim is to move the ball into the opposition's territory and score a goal (2)(3)(4)(5). ...
Introduction: This exploratory study aimed to assess the relationship between athlete neuromuscular performance and rugby performance indicators. Specifically, the study looked at the force-velocity profiles (FVPs) derived from four common resistance exercises and their relationship with rugby performance indicators (RPIs).
Methods: The study recruited twenty-two semi-professional male rugby players (body mass 102.5 ± 12.6 kg, height 1.85 ± 0.74 m, age 24.4 ± 3.4 years) consisting of ten backs and twelve forwards. Prior to the first game of a Covid-impacted nine-match season, participants performed four common resistance exercises (barbell box squat, jammer push-press, sled pull, and sled push) at incremental loads to establish force-velocity profiles. During the season, rugby performance indicators (post-contact metres, tries, turnovers conceded, tackles, try assists, metres ran, defenders beaten, and tackle breaks) were collated from two trusted sources by a performance analyst. Correlational analyses were used to determine the relationship between the results of FVPs and RPIs.
Results: The study found a statistically significant, moderate, positive correlation between tackle-breaks and sled push V0 (r = .35, p = .048). Significant, large, positive correlations were also found between tackles and jammer push-press V0 (r = .53, p = .049) and tackle-breaks and sled pull F0 (r = .53, p = .03). There was a significant, negative relationship between sled pull V0 and tackle-breaks (r = −.49, p = .04). However, the largest, significant correlation reported was between metres ran and sled pull F0 (r = .66, p = .03).
Conclusion: The study suggests that a relationship may exist between FVPs of particular exercises and RPIs, but further research is required to confirm this. Specifically, the results suggest that horizontal resistance training may be best to enhance RPIs (tackle-breaks, tackles, and metres ran). The study also found that maximal power was not related to any rugby performance indicator, which suggests that a specified prescription of either force or velocity dominant exercises to enhance RPIs may be warranted.
... Basados en las características de la posición, estos hallazgos podrían explicarse por el hecho de que los backs deben alcanzan velocidades superiores que los forwards en los desplazamientos a máxima velocidad 10 . Asimismo, otra razón la cual podría explicar estos resultados, son las características antropométricas de los backs, los cuales tienen una menor masa corporal en relación a los forwards 38 . Por lo tanto, ambas condiciones les permitirían a los backs alcanzar velocidades más altas en la ejecución del CMJ y en los valores en índice de fuerza reactiva. ...
Objetivo: Describir y comparar distintas variables del salto en contramovimiento (CMJ) incluyendo las variables cinéticas relativas al peso entre dos posiciones de juego en el Rugby Union, y determinar las posibles asociaciones con las características antropométricas y las cualidades físicas de jugadores estudiantes universitarios chilenos de Rugby Amateurs. Métodos: Los participantes fueron 32 jugadores universitarios varones (23,3 ± 5,4 años). Los saltos CMJ se realizaron en una plataforma de fuerza. Además, se realizaron evaluaciones físicas (evaluación de fuerza máxima de sentadilla profunda y press de banca, velocidad en 30 metros, bronco test y flexibilidad de isquiotibiales), y se evaluó las variables antropométricas peso, talla, masa muscular y adiposa. Resultados: Existe una diferencia significativa en las producciones de fuerza pico concéntrica (FPC) como de fuerza pico excéntrica (FPE) entre las posiciones de juego forwards y backs (p=0,007), donde en la FPC los forwards estuvieron un 14,5% por sobre los backs (2233,8 ± 371,3 vs 1899,3 ± 216,7 Newton), y en FPE obtuvieron un 11% de rendimiento por sobre los backs (2112,2 ± 393,3 vs 1888,3 ± 223,3 Newton). Adicionalmente, en la fuerza neta, los forwards obtuvieron una diferencia significativa (p=0.018) por sobre los backs (1421,6 ± 306,7 vs 1179,6 ± 201,3 Newton). Conclusión: Según los hallazgos obtenidos en este estudio, se propone la utilidad práctica y contribución de la utilización de la evaluación del CMJ en jugadores de Rugby Union, como una estrategia que permita monitorear y controlar el desarrollo y la progresión física de los jugadores.
... Maximal sprinting speed (MSS) is an essential component of success in many sports [1][2][3][4][5][6]. Therefore, the best training methods to improve sprint performance are of interest to many strength and conditioning coaches and scientists [7][8][9][10][11]. ...
Background: Maximal sprinting speed (MSS) is an essential component of success in many sports. Currently, many systems are used to accurately evaluate athletes’ MSS, including laser or radar guns, single- or dual-beam photocells, high-speed cameras, and high-frequency global positioning systems. However, the cost of these devices may be an obstacle to their implementation into practice. The least expensive but most likely less accurate alternative method of MSS evaluation is the hand-held time measurement of a 30m flying-start sprint. Therefore, the aim of the study was to assess the concurrent validity and inter-rater reliability o the hand-held method of MSS measurement. Materials and Methods: The study involved 3 experienced raters and 18 amateur runners. Runners performed 2-3 trials of the 30m maximal flying-start sprint. In total, 40 observations were collected. Each sprint time was measured simultaneously by raters using a hand-held stopwatch and an electronic timing system. Criterion validity (hand-held vs. electronic timing) was assessed using linear regression analysis. Inter-rater reliability between hand-held timers was evaluated using interclass correlation coefficients (ICCs), standard error of measurement (SEM), and minimal detectable change (MDC). Results: Results showed that single and average hand-held methods are affected by -0.17 to -0.07m·s-1 (-2.5 to -1.6%) and -0.12m·s- 1 (-1.7%) errors, respectively. Linear regression analysis parameters (free parameter not statistically significant, directional coefficient 0.994-1.057, standard error of estimation 0.073-0.125, R2 0.981-0.994) indicated statistically excellent absolute agreement between a hand-held (single and average) and electronic timing. ICCs of 0.980-0.994, SEM of 0.12m·s-1 (1.87%), and MDC of 0.34m·s-1 (5.18%) indicated statistically excellent absolute agreement and consistency for single and average measurements between hand-held timers. Conclusion: The proposed manual method of MSS measurement underestimates athletes’ speed performance. Moreover, the hand-held 30m flying-start sprint time measurement is affected by a 2% error, and a minimum 5% time change in an individual athlete demonstrates that the change is not simply attributable to measurement error.
... However, during the initial steps of a sprint (approximately ≤ 5 m) these studies have typically focussed on participants from team sports outside of rugby union, or on rugby union players competing at an amateur level. Given that differences exist in the sprinting performances, anthropometrics and strength capabilities between athletes in different team sports, and between competitive standards within rugby union (Brazier et al., 2020), the relationships between these performer constraints may differ in full-time professional rugby union backs, which form the focus of this thesis, compared with those already observed in team sport players in the available literature. Accordingly, one of the aims of this chapter was to answer research question III -How are lower limb strength qualities related to the performance of professional rugby backs during initial acceleration? ...
Biomechanics and motor control of early acceleration: Enhancing the initial sprint performance of professional rugby union backs Sprint acceleration is an important performance feature in many sports. For professional rugby union backs, short distance sprints are frequently carried out in training and competition, but how technique and strength-based characteristics contribute to their acceleration performance during these initial steps is not currently well understood. A series of investigations were therefore undertaken to, firstly, advance the understanding of this area and, secondly, to apply this information by prescribing individual-specific interventions to enhance initial acceleration performance. Three initial investigations sought to determine how technical features and strength-based qualities of professional rugby union backs related to their sprint performance (quantified as normalised average horizontal external power) during the initial steps. Findings from these investigations highlighted that focussing on the contribution of discrete technical variables to acceleration performance in isolation is an overly reductionist approach which overlooks how complex systems achieve high sprint performance. Findings also highlighted how important information on individuals can be lost using group-based study designs, since different inter-athlete strategies were adopted to achieve similar performance outcomes. In the fourth investigation, four subgroups of participants were identified, using cluster analysis, based on their whole-body kinematic strategies. At the intra-individual level, the variables which portrayed their individual strategies remained stable (CV: 1.9% to 6.7%) across multiple separate occasions. This characterisation of whole-body strategies was used to develop a novel and rigorous approach to longitudinally assess the efficacy of technical-based acceleration interventions. Demonstrating the application of this approach in the final investigation, several individual-specific interventions were prescribed to professional rugby union backs based on within-individual relationships of their technique strategies and strength-based capabilities with acceleration performance. Changes in within-individual technique and acceleration performance were measured at multiple time points across an 18-week intervention period where meaningful enhancements in acceleration were observed. This demonstrated that individual-specific technical interventions were effective in manipulating aspects of acceleration technique and performance. The outcome of these investigations provides a novel approach for practitioners working to individualise sprint-based practices.
... The advent of wearable microsensor technology has assisted athletic performance staff in capturing a much greater number of matches, with some systems capable of automatically detecting RHIE bouts within match-play. Although single running, acceleration and collision efforts are well understood [5,15,16], there is a dearth of literature describing the positional and contextual factors that influence RHIE activity in elite rugby union match-play. ...
The current investigation aimed to understand the differing positional demands across two elite rugby union competitions, with special reference to high-intensity effort (HIE) and repeated high-intensity effort (RHIE) activity. Four hundred and forty-one (n = 441) individual game files from thirty-five competitive games from the European Rugby Champions Cup (tier 1; n = 8) and PRO12 League (tier 2; n = 24) were analysed. Players' locomotor profiles were recorded using wearable global positioning system microtechnology (10 Hz Catapult S5, Catapult Innovations, Australia). Locomotor activities were classified as running (≥4.4 m•s −1), high-speed running (≥5.5 m•s −1), accelerations (≥2 m•s −2) and decelerations (≤−2 m•s −2). Data was gathered on collisions (≥4 g −1), high-intensity efforts (HIE), repeated high-intensity efforts (RHIE), average number of efforts within a RHIE bout (n) and maximal number of efforts within a RHIE bout (n). Overall locomotor differences between competitions were trivial to small in nature, with tier 1 competition associated with a larger number of RHIE bouts (6.5 ± 1.4 vs. 5.7 ± 1.5, effect size, ES = 0.55) and efforts per bout (3.0 ± 1.1 vs. 2.4 ± 1.2, ES = 0.52). Collisions comprised a greater proportion of total HIE for forwards within tier 1 competition compared to tier 2 competition. The hooker (mean difference: 4 [−10 to 14]; ES = 0.30, small), lock (mean difference: 5 [−12 to 23]; ES = 0.36, small) and backrow (mean difference: 8 [−10 to 15]; ES = 0.54, small) positions engaged in more collisions during tier 1 competition compared to tier 2 competition. These findings can be used by athletic performance staff to design game-specific drills and recovery strategies during different competition weeks to ensure players are appropriately prepared for the differing demands of elite rugby competition.
... Elite rugby has one of the highest reported injury incidences of any professional sport Brooks and Kemp (2008). This is likely due to a combination of well-established injury surveillance systems and the characteristics of the game, whereby high-impact body collision frequently occurs, in addition to the high intensity, multispeed and multidirectional nature of play Brazier et al. (2020). Meta-analyses have reported the total incidence of injury (injuries per 1000 player h) as 81/1000 in matches (∼3 injuries per match) and 3/1000 in training for elite rugby union (RU) athletes, with the majority being tendon, ligament and muscle injuries of the lower limb Williams, Trewartha, Kemp, and Stokes (2013). ...
There is growing evidence of genetic contributions to tendon and ligament pathologies. Given the high incidence and severity of tendon and ligament injuries in elite rugby, we studied whether 13 gene polymorphisms previously associated with tendon/ligament injury were associated with elite athlete status. Participants from the RugbyGene project were 663 elite Caucasian male rugby athletes (RA) (mean (standard deviation) height 1.85 (0.07) m, mass 101 (12) kg, age 29 (7) yr), including 558 rugby union athletes (RU) and 105 rugby league athletes. Non-athletes (NA) were 909 Caucasian men and women (56% female; height 1.70 (0.10) m, mass 72 (13) kg, age 41 (23) yr). Genotypes were determined using TaqMan probes and groups compared using Χ² and odds ratio (OR). COLGALT1 rs8090 AA genotype was more frequent in RA (27%) than NA (23%; P = 0.006). COL3A1 rs1800255 A allele was more frequent in RA (26%) than NA (23%) due to a greater frequency of GA genotype (39% vs 33%). For MIR608 rs4919510, RA had 1.7 times the odds of carrying the CC genotype compared to NA. MMP3 rs591058 TT genotype was less common in RA (25.1%) than NA (31.2%; P < 0.04). For NID1 rs4660148, RA had 1.6 times the odds of carrying the TT genotype compared to NA. It appears that elite rugby athletes have an inherited advantage that contributes to their elite status, possibly via resistance to soft tissue injury. These data may, in future, assist personalised management of injury risk amongst athletes.
Highlights
• The elite rugby athletes we studied had differing genetic characteristics to non-athletes regarding genetic variants previously associated with soft-tissue injury risk.
• COLGALT1 rs8090, COL3A1 rs1800255, MIR608 rs4919510, MMP3 rs591058 and NID1 rs4660148 were all associated with elite status in rugby.
• We propose that elite rugby athletes might possess an inherited resistance to soft tissue injury, which has enabled them to achieve elite status despite exposure to the high-risk environment of elite rugby.
... However, to our knowledge, no study has sought to replicate these associations or investigate whether the distribution of those genotypes associated with V O2max training adaptation differs between the general population and groups where enhanced training adaptations may be advantageous, such as elite athletes. In addition, team sports such as rugby union include different playing positions with variable match demands 12,13 and differences in aerobic performance between these positions 14 . This suggests that some athletes may have an inherited benefit of an enhanced capacity for cardiorespiratory adaptation. ...
Purpose:
Genetic polymorphisms have been associated with the adaptation to training in maximal oxygen uptake (VO2max). However, the genotype distribution of selected polymorphisms in athletic cohorts is unknown, with their influence on performance characteristics also undetermined. This study investigated whether the genotype distributions of 3 polymorphisms previously associated with VO2max training adaptation are associated with elite athlete status and performance characteristics in runners and rugby athletes, competitors for whom aerobic metabolism is important.
Methods: Genomic DNA was collected from 732 men including 165 long-distance runners, 212 elite rugby union athletes, and 355 nonathletes. Genotype and allele frequencies of PRDM1 rs10499043 C/T, GRIN3A rs1535628 G/A, and KCNH8 rs4973706 T/C were compared between athletes and nonathletes. Personal-best marathon times in runners, as well as in-game performance variables and playing position, of rugby athletes were analyzed according to genotype.
Results: Runners with PRDM1 T alleles recorded marathon times ∼3 minutes faster than CC homozygotes (02:27:55 [00:07:32] h vs 02:31:03 [00:08:24] h, P = .023). Rugby athletes had 1.57 times greater odds of possessing the KCNH8 TT genotype than nonathletes (65.5% vs 54.7%, χ2 = 6.494, P = .013). No other associations were identified.
Conclusions: This study is the first to demonstrate that polymorphisms previously associated with VO2max training adaptations in nonathletes are also associated with marathon performance (PRDM1) and elite rugby union status (KCNH8). The genotypes and alleles previously associated with superior endurance-training adaptation appear to be advantageous in long-distance running and achieving elite status in rugby union.
... quarterbacks and wide receivers) tend to be smaller, faster, and more aerobically fit (Robbins, 2011). This physical specificity concerning the tactic is also observed in rugby (Brazier et al., 2020;Roberts et al., 2008). Differences in physical demands according to the players' position have been found in team sports such as football and handball (Manchado et al., 2020). ...
The use of technology within sport is well established, most professional sport teams engage with the use of Electronic Performance and Tracking Systems. This book is the first to offer a dep and structured examination of these technologies and how they are used in a team sport setting.
The Use of Applied Technology in Team Sport describes and assists researchers, academics and professionals with understanding the methodology around applied technology in sport examining; what systems track players performance, who are the manufacturers that provide these systems.
This new volume goes on to describe how to apply the systems and highlights the ways of reporting analysis information and helps the reader to know and understand the future avenues of research and development.
The Use of Applied Technology in Team Sport is considered an essential guide for researchers, academics and students as well as professionals working in the areas of Applied Sport Science, Coaching, and subjects relating to Physiology, Biomechanics, Sports Engineering, Sports Technology and Performance Analysis in Sport.
... The efficacy of training in youth and adolescent rugby players has been investigated [14], showing that substantial developments can be achieved with different approaches of effective rugby training programs to improve performance. However, the specific demands of competition differ markedly between forwards and backs [15], making it necessary to better understand these (potential) differences across the different playing positions. ...
The purpose of this study was to compare measures of anthropometry characteristics and physical fitness performance between rugby union players (17.9 ± 0.5 years old) recruited (n = 39) and non-recruited (n = 145) to the Portuguese under-19 (U19) national team, controlling for their playing position (forwards or backs). Standardized anthropometric, physical, and performance assessment tests included players’ body mass and height, push up and pull-up test, squat test, sit-and-reach test, 20 m shuttle run test, flexed arm hang test, Sargent test, handgrip strength test, Illinois agility test, and 20-m and 50-m sprint test. Results showed that recruited forwards players had better agility scores (p = 0.02, ES = −0.55) than the non-recruited forwards, whereas recruited backs players had higher right (p < 0.01, ES = 0.84) and left (p = 0.01, ES = 0.74) handgrip strength scores than their counterparts. Logistic regression showed that better agility (for the forwards) and right handgrip strength scores (for the backs) were the only variables significantly associated with an increased likelihood of being recruited to the national team. In sum, these findings suggest that certain well-developed physical qualities, namely, agility for the forwards players and upper-body strength for the back players, partially explain the selection of U19 rugby players to their national team.
... This study did not address the positional or unit specific requirements for players of rugby union. There are significant differences from a physiological point of view between rugby union forwards and rugby union backs [29]. This study examined, sagittal plane and frontal plane isometric neck strength alone, it is acknowledged that these two planes of motion are not the only contributing factors contributing to overall neck stability. ...
The objective of this systematic literature review was to evaluate the evidence regarding the development of neck strength in reducing concussion and cervical spine injuries in adult amateur and professional sport populations. PubMed, CINAHL, Science Direct, and Web of Science databases were searched systematically. The criteria for inclusion in the review were as follows: (1) a human adult (≥18 or above); (2) involved in amateur, semi-professional, or professional sports; (3) sports included involved collisions with other humans, apparatus or the environment; (4) interventions included pre- and post-neck muscle strength measures or neck stability measures; (5) outcomes included effects on increasing neck strength in participants and/or injury incidence. Database searches identified 2462 articles. Following title, abstract, and full paper screening, three papers were eligible for inclusion. All of the papers reported information from male participants, two were focused on rugby union, and one on American football. Two of the included studies found a significant improvement in isometric neck strength following intervention. None of the studies reported any impact of neck strengthening exercises on cervical spine injuries. This review has shown that there is currently a lack of evidence to support the use of neck strengthening interventions in reducing impact injury risk in adult populations who participate in sport.
... Specifically in rugby, an elite player must be proficient over the different phases of sprinting, including acceleration and maximum velocity (Cross et al., 2015). Maximum sprint speed (MSS) is crucial to achieve superior performance in rugby (Brazier et al., 2020), hence, frequent monitoring is needed to evaluate the effectiveness of speed training programmes and ensure the adequate evolution of this capability throughout the athletic development (or even over the season) (Roe et al., 2017). Likewise, the measurement of MSS allows practitioners to establish individual thresholds for match analysis and monitoring training loads (Buchheit et al., 2012;Takamori et al., 2020). ...
This study assessed the validity of 5-m (TG5) and 10-m (TG10) split times measured with timing gates to estimate maximum sprint speed (MSS) against a criterion measure radar gun (RG) during the maximum velocity phase of a 30-m sprint. Nineteen amateur rugby players performed two 30-m sprints. The timing gates were placed at the starting line and at 5-, 10-, 20-, 25- and 30-m. In addition, a RG was used to measure instantaneous velocity. Both trials per participant were used selected as references. MSS obtained from TG10, TG5 and RG showed high intraclass correlation coefficients (0.971-0.978), low coefficients of variation (1.14-1.70%) and smallest detectable changes (< 0.02 m/s). Pairwise comparison revealed differences (p = 0.002) in MSS when comparing TG10 to RG, but not TG5 and RG (p = 0.957). Almost perfect correlations were found between RG, TG5 and TG10 (r > 0.926, p < 0.001). In conclusion, MSS obtained from TG5, TG10 and RG presented good intra-session reliability. However, practitioners should be aware that substantial differences exist between TG10 and RG. For the assessment of MSS in team-sport athletes, it is recommended the use of TG5 for more accurate estimations when a gold standard criterion is not available.
... The sport of RU requires a range of fitness characteristics, such as strength, power, speed, and aerobic fitness, in order to perform well and meet the demands of the sport [5,6]. Players all possess varying levels of physical characteristics, such as anthropometric (height, body mass, skinfold) and body composition (lean mass, fat mass, bone mass) in order to achieve adequate levels of the desired aforementioned fitness qualities and to meet specific positional demands of the sport [7][8][9]. Numerous studies have shown that these fitness [5,7,10] and physical characteristics [11][12][13][14][15][16] vary greatly depending on the player's position within the team. In general, forwards have a greater body mass and strength emphasis in order to scrummage with more force, tolerate more collisions and gain and retain possession of the ball [11]. ...
This study explored the physical and fitness characteristics of elite professional rugby union players and examined the relationships between these characteristics within forwards and backs. Thirty-nine elite professional rugby union players from the New Zealand Super Rugby Championship participated in this study. Body composition was measured using dual-energy X-ray absorptiometry alongside anthropometrics. Fitness characteristics included various strength, power, speed, and aerobic fitness measures. Forwards were significantly (p = < 0.01) taller and heavier than backs, and possessed greater lean mass, fat mass, fat percentage, bone mass, and skinfolds. Forwards demonstrated greater strength and absolute power measures than backs (p = 0.02), but were slower and possessed less aerobic fitness (p = < 0.01). Skinfolds demonstrated very large correlations with relative power (r = −0.84) and speed (r = 0.75) measures within forwards, while backs demonstrated large correlations between skinfolds and aerobic fitness (r = −0.54). Fat mass and fat percentage demonstrated very large correlations with speed (r = 0.71) and aerobic fitness (r = −0.70) measures within forwards. Skinfolds, fat mass, and fat percentage relate strongly to key fitness characteristics required for elite professional rugby union performance. Individual and positional monitoring is important due to the clear differences between positions.
Sports coaching involves navigating ambiguity and uncertainty in stakeholders’ perspectives and managing a dynamic micro-political environment. This study explores the relationship between coaching efficacy and effectiveness in South African Women's Rugby. It examines how a coach's belief in their ability to influence athlete learning and performance (coaching efficacy) correlates with the actual impact on athletes (coaching effectiveness). By aligning coaches’ perceived competence with tangible athlete outcomes, the study provides insights into factors influencing coaching practices and athlete development. The study involved 28 women players (mean age: 24.8 ± 4.0 years) and 8 coaches (mean age: 41 ± 3.8 years) who participated in semi-structured online interviews. The interview script, derived from the Coaching Effectiveness Survey (CES) tool, was analysed using Braun and Clarke's 6-step process of thematic content analysis. Under the four efficacy dimensions, sub-themes emerged as follow: 1) motivation (climate created by the coach and a motivational climate experienced by the players), 2) technique (coaching physical, technical, and tactical aspects of rugby), 3) game strategy (guiding players to successful outcomes), and 4) character-building efficacy (cultivating a positive environment for sportswomanship and holistic development). The findings incorporate feedback from players and coaches, highlighting firsthand experiences of coaching effectiveness. This approach enables experts to identify effective coaching strategies and those needing refinement within Women's Rugby. The study's findings promise to inform future coach development frameworks and foster a comprehensive understanding of coaching effectiveness in the dynamic landscape of Women's Rugby worldwide.
Objective: To investigate the relationship between body composition and physical fitness characteristics of collegiate rugby union players and explore their physical profiles based on their playing positions. Method: High-level collegiate players (n = 27, age = 21.2 ± 1.1 years) that were grouped in two playing positions, as forwards and backs were assessed. Data were collected for body weight (BW), height, body composition (body fat percentage [BF%] and lean body mass [LBM]), 3-sec sprint test (3SST), Illinois change of direction (ICOD), vertical jump (VJT), and aerobic fitness (VO2 max). Results: Forwards players presented significantly higher BW, BF%, and LBM compared to backs players. Backs players were significantly faster and had better VO2 max than the forwards players. Depending on playing positions, BF% and LBM showed a moderate to strong relationship with physical fitness performances. Conclusion: Anthropometric such as height, BW, LBM, and VO2 max can be a contributing factor in determining players’ playing positions and their appropriate playing standards in rugby union. Level of Evidence III; Retrospective Comparative Study.
Background
Youth swimming performance is determined by several physiological, biomechanical and anthropometric characteristics. This review aimed to identify physical performance determinants of youth swimming performance, assessing strength, power, anaerobic, aerobic and body composition measures. ̇
Methods
Searches were conducted in electronic databases (PubMed and Web of Science) using keywords relating to swimming and physiological measures, supplemented by citation searching of similar reviews. A total of 843 studies were identified in the initial search. The following inclusion criteria were used: participants were competitive/trained swimmers; swimming time-trial or event was conducted; data was provided on one or more physiological parameters; study was published in English and peer-reviewed. A total of 43 studies met the inclusion criteria. Risk of bias was assessed using Joanna Briggs Institute (JBI) checklist.
Results
Cross-sectional studies scored between 4–8 and randomised-controlled trials scored 8–9 on their respective JBI checklists. Youth swimming performance was determined by muscle strength, muscle power, lean body mass, anaerobic and aerobic metabolism measures in most studies, where improved performance values of these variables were conducive to swimming performance. Body fat percentage did not have a clear relationship in youth swimming performance.
Conclusions
Findings of this review suggest that greater levels of muscle strength, muscle power and lean body mass are favourable in swimming performance, with muscle strength and muscle power particularly beneficial for start and turn performance. Anaerobic and aerobic metabolism measures were good determinants of swimming performance, with middle- and long-distance events more influenced by the latter. Body fat percentage has a nuanced relationship with swimming performance, where further investigation is required. Findings were inconsistent across studies, potentially due to unidentified confounding factors.
Key points
• Greater muscular strength and power qualities, anaerobic and aerobic capacities, and lean body mass are conducive to swimming performance.
• Body fat percentage has a nuanced relationship with swimming performance.
• Practitioners should consider general strength and power training as a useful tool to enhance performance in their youth competitors.
The objective was to analyse the associations between anthropometric characteristics and diet in male rugby players according to the playing position. A cross-sectional study was developed. The forwards had higher body weight (107 kg) and fat mass (FM; 12%) than the backs (87.8 kg and 8.47%, respectively) (p < 0.05). The quality of diet needs to improve (KIDMED value of 5.87 and 6.36 for forwards and backs, respectively). Nutritional imbalances, such as deficits in carbohydrates, fibre, calcium, magnesium and vitamin D, and excess of fats, saturated fatty acid, cholesterol and sugars were found. Carbohydrates and proteins intake were significant associated (p < 0.05) with a minor FM. Forwards with a KIDMED index of less than 8 had a significantly higher FM than those who maintained an optimal diet (p < 0.05). The diet of rugby players should be more in line with dietary recommendations and take into account the player position to optimise sports performance.
Ragbi müsabakasında oyuncular topu taşımaya çalışarak zorlu bir fiziksel mücadele verirken oyun içerisinde topa sahip olmak ve konum avantajını sağlamak için yürüme, sprint ve top taşıma gibi birçok aktiviteyi tekrarlamaktadır. Ragbi müsabakalarının fiziksel ve fizyolojik gereklilikleri, oyun içinde farklı pozisyonlarda oyuncular gerektirmektedir ve bu oyuncuların saha içindeki pozisyonlarının da yüksek müsabaka performansı için özel bir rolü vardır. Bu araştırmada Üniligde yer alan üniversite Yedili Ragbi takımında yer alan yedi faklı oyun içi pozisyonun üçü forvet (forward) dördü de bek (back) olarak değerlendirilmiştir. Bu bağlamda bu araştırmada ragbi müsabakalarında iki farklı mevkide mücadele eden sporcuların fiziksel ve fizyolojik özellikleri tespit edilerek, bu özelliklerin mevkilere göre farklılık gösterip göstermediği incelenmiştir. Araştırmaya, 2022 yılında Ünilig müsabakalarına katılmış olan Bartın Üniversitesi Ragbi takımında yer alan yaş ortalamaları 22,06±1,23yıl olan aktif 16 erkek Ragbi sporcusu dahil edilmiştir. Katılımcılara vücut kompozisyonu, çeviklik, esneklik, kuvvet ve anaerobik performans ölçümleri yapılmıştır. Analizler sonucu Forvet ve Bek oyuncu grupları arasında vücut ağırlığı, beden kitle indeksi, bacak kuvveti, sol el kavrama kuvveti skorları arasında istatistiksel anlamlı farklığın olduğu, fakat boy uzunluğu, vücut yağ oranı, sırt kuvveti, esneklik, sağ el kavrama kuvveti, çeviklik ve anaerobik performans değişkenlerinde istatistiksel olarak anlamlı farklığın olmadığı tespit edilmiştir (p
RESUMEN Introducción: El rugby es un deporte colectivo dónde se deben tener en cuenta las características físicas y fisiológicas de los deportistas de acuerdo a las posiciones de juago, pues los forwards tendrán más colisiones físicas que los backs, por lo cual deben presentar una masa muscular alta, y un somatotipo donde prevalezca la mesomorfia y la endomorfia sobre la ectomorfia, es decir que tengan robustez, articulaciones grandes y masa muscular preponderante. Objetivo: esta investigación pretendió Identificar el somatotipo de los deportistas de género masculino del equipo de Rugby Seven de la Fundación Universitaria Juan de Castellanos. Metodología: Es una investigación descriptiva, no experimental, de corte transversal y con un enfoque cuantitativo. Donde se evaluaron 14 deportistas con una edad promedio de 22,22 ± 1,67 años, un peso promedio de 71,36 ± 10,12 kg y una talla promedio de 1,72 ± 0,04 mts. Resultados: Los resultados permiten evidenciar la prevalencia del somatotipo mesomorfo-ectomorfo tanto en los backs como en los forwards con características como la prevalencia de la linealidad corporal y un bajo volumen muscular por unidad de altura. Conclusión: Con el fin de un mejor desempeño es necesario buscar un somatotipo meso-endomorfo, con ayuda de la nutrición y un plan de entrenamiento orientado hacia la hipertrofia muscular, cumpliendo las necesidades morfofuncionales del Rugby. ABSTRACT Introduction: Rugby is a collective sport where the physical and physiological characteristics of the athletes must be taken into account according to the playing positions, since the forwards will have more physical
Background
Youth swimming performance is determined by several physiological, biomechanical and anthropometric characteristics. This review aimed to identify physical performance determinants of youth swimming performance, assessing strength, power, anaerobic, aerobic and body composition measures.
Methods
Searches were conducted in electronic databases (PubMed and Web of Science) using keywords relating to swimming and physiological measures, supplemented by citation searching of similar reviews. A total of 795 studies were identified in the initial search. The following inclusion criteria were used: participants were competitive/trained swimmers; swimming time-trial or event was conducted; data was provided on one or more physiological parameters; study was published in English and peer-reviewed. A total of 43 studies met the inclusion criteria. Risk of bias was assessed using Joanna Briggs Institute (JBI) checklist.
Results
Cross-sectional studies scored between 4–8 and randomised-controlled trials scored 8–9 on their respective JBI checklists. Youth swimming performance was determined by muscle strength, muscle power, lean body mass, anaerobic and aerobic metabolism measures in most studies, where improved performance values of these variables were conducive to swimming performance. Bodyfat % did not have a clear relationship with SP in youth performers.
Conclusions
Findings of this review suggest that greater levels of muscle strength, muscle power and lean body mass are favourable in swimming performance, with muscle strength and muscle power particularly beneficial for start and turn performance. Anaerobic and aerobic metabolism measures were good determinants of swimming performance, with middle- and long-distance events more influenced by the latter. Bodyfat % has a nuanced relationship with swimming performance, where further investigation is required. Findings were inconsistent across studies, potentially due to unidentified confounding factors. The evidence suggests enhanced physiological factors of strength, power and lean body mass in youth swimmers improves overall swim performance.
The effectiveness of offensive ball-carrying has been identified as a key determinant in elite rugby union try-scoring success and subsequent match outcome. Despite this, there is limited research evaluating the physical qualities believed to underpin ball-carrying capability amongst elite rugby union players. The aim of this review was to critically appraise the scientific literature that has investigated the use of physical characteristics to explain ball-carrying capability in elite rugby union. Measures of sprint performance, specifically acceleration, maximum sprinting speed, and sprint momentum have presented weak-to-strong correlations with the number of tries scored, line breaks, tackle breaks, defenders beaten, and dominant collisions recorded amongst international rugby union players. In addition, unilateral and bilateral vertical countermovement jump height, peak power output, and drop jump reactive strength index have each demonstrated meaningful associations with the number of tries scored, line breaks, tackle breaks, and dominant collisions. However, various measures of maximal lower-body strength have presented only trivial correlations with the game statistics associated with ball-carrying capability. These trivial correlations are likely a result of the inconsistent and inaccurate methods used to assess maximal lower-body strength, with methods ranging from a box-squat predicted one-repetition maximum to a maximal isometric mid-thigh pull. Further investigation is required to assess the contribution of maximal lower-body strength, agility, repeated sprint ability, and aerobic capacity to ball-carrying capability in elite rugby union. Such robust, objective data could be used to inform the specificity of physical preparation and maximise the transfer of these physical qualities to on-field performance.
Purpose
The aims of the present study were two-fold: (i) to investigate the relationship between physical characteristics and the game statistics associated with ball-carrying capability amongst sub-elite rugby union players, and (ii) to predict the level of change in these physical characteristics required to improve the associated game statistic via regression analysis.
Methods
Thirty-eight senior professional players (forwards, n = 22; backs, n = 16) were assessed for body mass (BM), back squat (BS) single-repetition maximum (1RM) normalised to BM (1RM/BM), 10 m sprint velocity (S10), 10 m sprint momentum (SM10), and the game statistics from 22 games within the 2019/20 RFU Championship season. The relationship between these measures and the predicted level of change in a physical measure required to improve the total number of the associated game statistic by one were assessed by Pearson’s correlation coefficient and simple regression analyses.
Results
In forwards, an ~ 11.5% reduction in BM, an ~ 11.8% improvement in BS 1RM/BM, or an ~ 11.5% increase in S10 was required to improve the game statistics associated with ball-carrying capability. In backs, a ~ 19.3% increase in BM or a ~ 15.6% improvement in SM10 was required.
Conclusions
These findings demonstrate that improvements in lower-body relative strength, acceleration performance, and position-specific alterations in body mass are required to maximise the ball-carrying capability and therefore match outcome of sub-elite rugby union players.
Objectives
In part 1, the objective was to undertake a systematic scoping review of applied sports science and sports medicine in women’s rugby, and in part 2 to develop a consensus statement on future research priorities.
Design
In part 1, a systematic search of PubMed (MEDLINE), Scopus and SPORTDiscus (EBSCOhost) was undertaken from the earliest records to January 2021. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020, the PRISMA extension for Scoping Reviews, and the PRISMA extension protocols were followed. In part 2, 31 international experts in women’s rugby (ie, elite players, sports scientists, medical clinicians, sports administrators) participated in a three-round Delphi consensus method. These experts reviewed the findings from part 1 and subsequently provided a list of priority research topics in women’s rugby. Research topics were grouped into expert-based themes and expert-based subthemes via content analysis. Expert-based themes and expert-based subthemes were ranked from very low to very high research priority on a 1–5 Likert scale. Consensus was defined by ≥70% agreement. The median research priority agreement and IQR were calculated for each expert-based theme and subtheme.
Data sources
PubMed (MEDLINE), Scopus and SPORTDiscus (EBSCOhost).
Eligibility criteria for selecting studies
Studies were eligible for inclusion if they investigated applied sports science or sports medicine in women’s rugby.
Results
In part 1, the systematic scoping review identified 123 studies, which were categorised into six sports science and sports medicine evidence-based themes: injury (n=48), physical performance (n=32), match characteristics (n=26), fatigue and recovery (n=6), nutrition (n=6), and psychology (n=5). In part 2, the Delphi method resulted in three expert-based themes achieving consensus on future research priority in women’s rugby: injury (5.0 (1.0)), female health (4.0 (1.0)) and physical performance (4.0 (1.0)).
Summary/Conclusion
This two-part systematic scoping review and Delphi consensus is the first study to summarise the applied sports science and sports medicine evidence base in women’s rugby and establish future research priorities. The summary tables from part 1 provide valuable reference information for researchers and practitioners. The three expert-based themes that achieved consensus in part 2 (injury, female health and physical performance) provide clear direction and guidance on future research priorities in women’s rugby. The findings of this two-part study facilitate efficient and coordinated use of scientific resources towards high-priority research themes relevant to a wide range of stakeholders in women’s rugby.
Women’s rugby (rugby league, rugby union and rugby sevens) has recently grown in participation and professionalisation. There is under- representation of women- only cohorts within applied sport science and medicine research and within the women’s rugby evidence base. The aims of this article are: Part 1: to undertake a systematic- scoping review of the applied sport science and medicine of women’s rugby, and Part 2: to develop a consensus statement on future research priorities. This article will be designed in two parts: Part 1: a systematic- scoping review, and Part 2: a three- round Delphi consensus method. For Part 1, systematic searches of three electronic databases (PubMed (MEDLINE), Scopus, SPORTDiscus (EBSCOhost)) will be performed from the earliest record. These databases will be searched to identify any sport science and medicine themed studies within women’s rugby. The Preferred Reporting Items for Systematic Reviews and Meta- analyses extension for Scoping Reviews will be adhered to. Part 2 involves a three- round Delphi consensus method to identify future research priorities. Identified experts in women’s rugby will be provided with overall findings from Part 1 to inform decision- making. Participants will then be asked to provide a list of research priority areas. Over the three rounds, priority areas achieving consensus (≥70% agreement) will be identified. This study has received institutional ethical approval. When complete, the manuscript will be submitted for publication in a peer- reviewed journal. The findings of this article will have relevance for a wide range of stakeholders in women’s rugby, including policymakers and governing bodies.
Background:
Rugby is a globally played sport with statistically significant variance in the physical fitness levels of rugby players in different playing positions. The aim of the study was to evaluate the physical fitness levels in rugby academy players and to determine the relationship between non-field and field tests based on the forward and backline playing positions.
Methods:
The study made use of cross-sectional, secondary data and employed a quantitative and correlational research design. Forty-five rugby academy players from a rugby academy in the Western Province were conveniently recruited for the study and split into forward and backline playing positions. The non-field tests were stature, body mass, and body fat percentage, bench-press, pull-ups, and vertical jump, while the field tests were the10m, 30m, and 40m sprints, the Broncho test, and the repeat sprintability test. Data analysis comprised independent samples t-test, Pearson's correlation, and linear and logistic regression analysis. The level of statistical significance was set at p<0.05.
Results:
Forwards were significantly heavier, stronger and more powerful than backline players (p < 0.05). Backline players had a lower body fat percentage, were faster, and had a higher anaerobic endurance capacity, and higher muscular endurance (p < 0.05). Body mass, body fat percentage, aerobic capacity, absolute muscular power, and relative muscular strength were all significant predictors of speed (p < 0.01), and body mass was a significant predictor of anaerobic capacity (p < 0.05).
Conclusions:
Forwards had higher absolute muscular strength and peak power output, whereas backs were significantly lighter, faster, relatively stronger, and possessed higher muscular endurance and were significantly influenced, in particular, by body composition and aerobic capacity.
Objective
The objective of this study was to investigate which anthropometric and physical performance variables characterised players that advanced to professional teams (professionals) and how these variables changed over time, compared to those that did not secure professional contracts (i.e. remained amateurs).
Methods
Differences in anthropometry, strength, speed, power and intermittent running ability in 83 male rugby players collected between 2015 and 2019 were determined using repeated measures analysis.
Results
When arriving for the first year of the program, forwards that went on to become professional players were older (0.4 ± 0.3 yr, mean ± 95% CI, p = 0.004), heavier (4.6 ± 2.5 kg, p < 0.001) and stronger (range 6.2-16.4%,) than forwards that remained amateur. Professional forwards were also slower at sprinting (range -2.7-2.9%, p < 0.001) and had lower Yo-Yo IRT L1 (-10.8%, p = 0.03). When first arrived on the program, professional backs were taller (3.5 ± 1.8 cm, p < 0.001), heavier (4.6 ± 2.4 kg, p < 0.001) and faster over 20 m (-1.9 ± 1.7%, p = 0.03) and 30 m (-1.7 ± 1.6%, p = 0.04) compared to amateurs. Compared to amateurs, professionals had a smaller increase in body mass (-4.2 ± 2.0%, p < 0.001) and greater improvement in sprinting (3.7, 2.8, 2.8% over 10, 20 and 30-m, respectively) and Yo-Yo IRT L1 (14.7 ± 11.0%, p = 0.05) over 3 years training.
Conclusion
Characteristics that are likely to assist players in becoming professionals include being older, heavier, taller and stronger.
Background
Two common single nucleotide polymorphisms within the COL5A1 gene (SNPs; rs12722 C/T and rs3196378 C/A) have previously been associated with tendon and ligament pathologies. Given the high incidence of tendon and ligament injuries in elite rugby athletes, we hypothesised that both SNPs would be associated with career success.
Results
In 1105 participants (RugbyGene project), comprising 460 elite rugby union (RU), 88 elite rugby league athletes and 565 non-athlete controls, DNA was collected and genotyped for the COL5A1 rs12722 and rs3196378 variants using real-time PCR. For rs12722, the injury-protective CC genotype and C allele were more common in all athletes (21% and 47%, respectively) and RU athletes (22% and 48%) than in controls (16% and 41%, P ≤ 0.01). For rs3196378, the CC genotype and C allele were overrepresented in all athletes (23% and 48%) and RU athletes (24% and 49%) compared with controls (16% and 41%, P ≤ 0.02). The CC genotype in particular was overrepresented in the back and centres (24%) compared with controls, with more than twice the odds (OR = 2.25, P = 0.006) of possessing the injury-protective CC genotype. Furthermore, when considering both SNPs simultaneously, the CC–CC SNP-SNP combination and C–C inferred allele combination were higher in all the athlete groups (≥18% and ≥43%) compared with controls (13% and 40%; P = 0.01). However, no genotype differences were identified for either SNP when RU playing positions were compared directly with each other.
Conclusion
It appears that the C alleles, CC genotypes and resulting combinations of both rs12722 and rs3196378 are beneficial for rugby athletes to achieve elite status and carriage of these variants may impart an inherited resistance against soft tissue injury, despite exposure to the high-risk environment of elite rugby. These data have implications for the management of inter-individual differences in injury risk amongst elite athletes.
The purpose of this investigation was to assess changes in strength, power, and levels of testosterone and cortisol over a 13-week elite competitive rugby union season. Thirty-two professional rugby union athletes from a Super 14 rugby team (age, 24.4 +/- 2.7 years; height, 184.7 +/- 6.2 cm; mass, 104.0 +/- 11.2 kg; mean +/- SD) were assessed for upper-body and lower-body strength (bench press and box squat, respectively) and power (bench throw and jump squat, respectively) up to 5 times throughout the competitive season. Salivary testosterone and cortisol samples, along with ratings of perceived soreness and tiredness, were also obtained before each power assessment. An effect size of 0.2 was interpreted as the smallest worthwhile change. A small increase in lower-body strength was observed over the study period (8.5%; 90% confidence limits +/-7.2%), whereas upper-body strength was maintained (-1.2%; +/-2.7%). Decreases in lower-body power (-3.3%; +/-5.5%) and upper-body power (-3.4; +/-4.9%) were small and trivial. There were moderate increases in testosterone (54%; +/-27%) and cortisol (97%; +/-51%) over the competitive season, and the testosterone to cortisol ratio showed a small decline (22%; +/-25%), whereas changes in perceived soreness and tiredness were trivial. Individual differences over the competitive season for all measures were mostly trivial or inestimable. Some small to moderate relationships were observed between strength and power; however, relationships between hormonal concentrations and performance were mainly trivial but unclear. Positive adaptation in strength and power may be primarily affected by cumulative training volume and stimulus over a competitive season. Greater than 2 resistance sessions per week may be needed to improve strength and power in elite rugby union athletes during a competitive season.
A number of studies have used global positioning systems (GPS) to report on positional differences in the physical game demands of rugby union both on an average and singular bout basis. However, the ability of these studies to report quantitative data is limited by a lack of validation of certain aspects of measurement by GPS micro-technology. Furthermore no study has analyzed the positional physical demands of the longest bouts of ball-in-play time in rugby union. The aim of the present study is to compare the demands of the single longest period of ball-in-play, termed “worst case scenario” (WCS) between positional groups, which have previously been reported to have distinguishable game demands. The results of this study indicate that WCS periods follow a similar sporadic pattern as average demands but are played at a far higher pace than previously reported for average game demands with average meters per minute of 116.8 m. The positional differences in running and collision activity previously reported are perpetuated within WCS periods. Backs covered greater total distances than forwards (318 m vs 289 m), carried out more high-speed running (11.1 m·min⁻¹ vs 5.5 m·min⁻¹) and achieved higher maximum velocities (MaxVel). Outside Backs achieved the highest MaxVel values (6.84 m·sec⁻¹). Tight Five and Back Row forwards underwent significantly more collisions than Inside Back and Outside Backs (0.73 & 0.89 collisions·min⁻¹ vs 0.28 & 0.41 collisions·min⁻¹ respectively). The results of the present study provide information on the positional physical requirements of performance in prolonged periods involving multiple high intensity bursts of effort. Although the current state of GPS micro-technology as a measurement tool does not permit reporting of collision intensity or acceleration data, the combined use of video and GPS provides valuable information to the practitioner. This can be used to match and replicate game demands in training.
Background
FTO gene variants have been associated with obesity phenotypes in sedentary and obese populations, but rarely with skeletal muscle and elite athlete phenotypes.
Methods
In 1089 participants, comprising 530 elite rugby athletes and 559 non-athletes, DNA was collected and genotyped for the FTO rs9939609 variant using real-time PCR. In a subgroup of non-resistance trained individuals (NT; n = 120), we also assessed structural and functional skeletal muscle phenotypes using dual energy x-ray absorptiometry, ultrasound and isokinetic dynamometry. In a subgroup of rugby athletes (n = 77), we assessed muscle power during a countermovement jump.
Results
In NT, TT genotype and T allele carriers had greater total body (4.8% and 4.1%) and total appendicular lean mass (LM; 3.0% and 2.1%) compared to AA genotype, with greater arm LM (0.8%) in T allele carriers and leg LM (2.1%) for TT, compared to AA genotype. Furthermore, the T allele was more common (94%) in selected elite rugby union athletes (back three and centre players) who are most reliant on LM rather than total body mass for success, compared to other rugby athletes (82%; P = 0.01, OR = 3.34) and controls (84%; P = 0.03, OR = 2.88). Accordingly, these athletes had greater peak power relative to body mass than other rugby athletes (14%; P = 2 x 10-6).
Conclusion
Collectively, these results suggest that the T allele is associated with increased LM and elite athletic success. This has implications for athletic populations, as well as conditions characterised by low LM such as sarcopenia and cachexia.
The aim of our study was to determine if there is a role for manipulation of g force thresholds acquired via micro-technology for accurately detecting collisions in rugby union. In total, 36 players were recruited from an elite Guinness Pro12 rugby union team. Player movement profiles and collisions were acquired via individual global positioning system (GPS) micro-technology units. Players were assigned to a sub-category of positions in order to determine positional collision demands. The coding of collisions by micro-technology at g force thresholds between 2 and 5.5 g (0.5 g increments) was compared with collision coding by an expert video analyst using Bland-Altman assessments. The most appropriate g force threshold (smallest mean difference compared with video analyst coding) was lower for all forwards positions (2.5 g) than for all backs positions (3.5 g). The Bland-Altman 95% limits of agreement indicated that there may be a substantial over- or underestimation of collisions coded via GPS micro-technology when using expert video analyst coding as the reference comparator. The manipulation of the g force thresholds applied to data acquired by GPS micro-technology units based on incremental thresholds of 0.5 g does not provide a reliable tool for the accurate coding of collisions in rugby union. Future research should aim to investigate smaller g force threshold increments and determine the events that cause coding of false positives.
The evaluation of rate of force development during rapid contractions has recently become quite popular for characterising explosive strength of athletes, elderly individuals and patients. The main aims of this narrative review are to describe the neuromuscular determinants of rate of force development and to discuss various methodological considerations inherent to its evaluation for research and clinical purposes. Rate of force development (1) seems to be mainly determined by the capacity to produce maximal voluntary activation in the early phase of an explosive contraction (first 50–75 ms), particularly as a result of increased motor unit discharge rate; (2) can be improved by both explosive-type and heavy-resistance strength training in different subject populations, mainly through an improvement in rapid muscle activation; (3) is quite difficult to evaluate in a valid and reliable way. Therefore, we provide evidence-based practical recommendations for rational quantification of rate of force development in both laboratory and clinical settings.
We aimed to quantify the ACE I/D and ACTN3 R577X (rs1815739) genetic variants in elite rugby athletes (rugby union and league), compare genotype frequencies to controls and between playing positions. The rugby athlete cohort consisted of 507 Caucasian men, including 431 rugby union athletes that for some analyses were divided into backs and forwards and into specific positional groups: front five, back row, half backs, centers and back three. Controls were 710 Caucasian men and women. Real-time PCR of genomic DNA was used to determine genotypes using TaqMan probes and groups were compared using Chi-square and odds ratio (OR) statistics. Correction of p-values for multiple comparisons was according to Benjamini-Hochberg. There was no difference in ACE I/D genotype between groups. ACTN3 XX genotype tended to be underrepresented in rugby union backs (15.7%) compared to forwards (24.8%; P=0.06). Interestingly, the 69 back three players (wings and full backs) in rugby union included only six XX genotype individuals (8.7%), with the R allele more common in the back three (68.8%) than controls (58.0%; χ(2)=6.672, P=0.04; OR=1.60) and forwards (47.5%; χ(2)=11.768, P=0.01; OR=2.00). Association of ACTN3 R577X with playing position in elite rugby union athletes suggests inherited fatigue resistance is more prevalent in forwards while inherited sprint ability is more prevalent in backs, especially wings and full backs. These results also demonstrate the advantage of focusing genetic studies on a large cohort within a single sport, especially when intra-sport positional differences exist, instead of combining several sports with varied demands and athlete characteristics.
The main purpose of the present meta-analysis was to examine the criterion-related validity of the 20-m shuttle run test for estimating cardiorespiratory fitness. Relevant studies were searched from twelve electronic databases up to December 2014, as well as from several alternative modes of searching. The Hunter-Schmidt’s psychometric meta-analysis approach was conducted to estimate the population criterion-related valid-ity of the 20-m shuttle run test. From 57 studies that were in-cluded in the present meta-analysis, a total of 78 correlation values were analyzed. The overall results showed that the per-formance score of the 20-m shuttle run test had a moderate-to-high criterion-related validity for estimating maximum oxygen uptake (rp = 0.66-0.84), being higher when other variables (e.g. sex, age or body mass) were used (rp = 0.78-0.95). The present meta-analysis also showed that the criterion-related validity of Léger’s protocol was statistically higher for adults (rp = 0.94, 0.87-1.00) than for children (rp = 0.78, 0.72-0.85). However, sex and maximum oxygen uptake level do not seem to affect the criterion-related validity values. When an individual’s maximum oxygen uptake attained during a laboratory-based test is not feasible, the 20-m shuttle run test seems to be a useful alterna-tive for estimating cardiorespiratory fitness. In adults the per-formance score only seems to be a strong estimator of cardi-orespiratory fitness, in contrast among children the performance score should be combined with other variables. Nevertheless, as in the application of any physical fitness field test, evaluators must be aware that the performance score of the 20-m shuttle run test is simply an estimation and not a direct measure of cardiorespiratory fitness.
This article introduces some aspects of sports genomics in a rugby union context, considers the rugby-specific genetic data in the published literature and outlines the next research steps required if the potential applications of genetic technology in rugby union, also identified here, are to become possible. A substantial proportion of the inter-individual variation for many traits related to rugby performance, including strength, short-term muscle power, VO2 max, injury susceptibility and the likelihood of being an elite athlete is inherited and can be investigated using molecular genetic techniques. In sports genomics, significant efforts have been made in recent years to develop large DNA biobanks of elite athletes for detailed exploration of the heritable bases of those traits. However, little effort has been devoted to the study of rugby athletes, and most of the little research that has focused on rugby was conducted with small cohorts of non-elite players. With steadily growing knowledge of the molecular mechanisms underpinning complex performance traits and the aetiology of injury, investigating sports genomics in the context of rugby is now a viable proposition and a worthwhile endeavour. The RugbyGene project we describe briefly in this article is a multi-institutional research collaboration in rugby union that will perform molecular genetic analyses of varying complexity. Genetic tests could become useful tools for rugby practitioners in the future and provide complementary and additional information to that provided by the non-genetic tests currently used.
This study assessed the positional and temporal movement patterns of professional rugby union players during competition using global positioning system (GPS) units. GPS data were collected from 33 professional rugby players from 13 matches throughout the 2012-2013 season sampling at 10 Hz. Players wore GPS units from which information on distances, velocities, accelerations, exertion index, player load, contacts, sprinting and repeated high-intensity efforts (RHIE) were derived. Data files from players who played over 60 min (n = 112) were separated into five positional groups (tight and loose forwards; half, inside and outside backs) for match analysis. A further comparison of temporal changes in movement patterns was also performed using data files from those who played full games (n = 71). Significant positional differences were found for movement characteristics during performance (P < 0.05). Results demonstrate that inside and outside backs have greatest high-speed running demands; however, RHIE and contact demands are greatest in loose forwards during match play. Temporal analysis of all players displayed significant differences in player load, cruising and striding between halves, with measures of low- and high-intensity movement and acceleration/deceleration significantly declining throughout each half. Our data demonstrate significant positional differences for a number of key movement variables which provide a greater understanding of positional requirements of performance. This in turn may be used to develop progressive position-specific drills that elicit specific adaptations and provide objective measures of preparedness. Knowledge of performance changes may be used when developing drills and should be considered when monitoring and evaluating performance.
Abstract Rugby league is a collision sport which traditionally adopts a large emphasis on lean muscle mass. Currently there is limited research on the anthropometry of European Super League players. The aim of this study was to assess body composition using Dual Energy X-ray Absorptiometry (DXA) scans to identify the typical profile of elite rugby league players. One hundred and twelve players from five different clubs competing in the European Super League were recruited for the study. DXA scans were performed and the total mass, lean mass, fat mass and percentage body fat were reported for each positional group. For the Fullback and Wingers, Centres, Half Backs, Hookers, Props and Back Row Forwards the mean (SD) body fat percentage was 13 (2.1), 13 (2.4), 12 (3.4), 15 (3.9), 16 (4.3) and 15 (2.1)%, respectively, and total mass was 86 (8.2), 91 (6.6), 81 (8), 84 (9.5) 102 (8.5) and 93 (5.5) kg, respectively. Despite small to very large inter positional differences in all anthropometric variables (effect sizes = -0.08 to 2.56), particularly between the Prop and the other playing positions, there was large intra-position variation in body fat, lean mass and total mass making a standardised position specific profile difficult to establish. When used with other key performance indicators, these data provide the first multi-team anthropometric profile of elite Super League players that can be used to guide individualised training and nutrition practices for current and aspiring athletes.
Purpose:
To compare mechanical properties of overground sprint running in elite rugby union and rugby league athletes.
Methods:
Thirty elite rugby code (15 rugby union and 15 rugby league) athletes participated in this cross-sectional analysis. Radar was used to measure maximal overground sprint performance over 20 or 30 m (forwards and backs, respectively). In addition to time at 2, 5, 10, 20, and 30 m, velocity-time signals were analyzed to derive external horizontal force-velocity relationships with a recently validated method. From this relationship, the maximal theoretical velocity, external relative and absolute horizontal force, horizontal power, and optimal horizontal force for peak power production were determined.
Results:
While differences in maximal velocity were unclear between codes, rugby union backs produced moderately faster split times, with the most substantial differences occurring at 2 and 5 m (ES 0.95 and 0.86, respectively). In addition, rugby union backs produced moderately larger relative horizontal force, optimal force, and peak power capabilities than rugby league backs (ES 0.73-0.77). Rugby union forwards had a higher absolute force (ES 0.77) despite having ~12% more body weight than rugby league forwards.
Conclusions:
In this elite sample, rugby union athletes typically displayed greater short-distance sprint performance, which may be linked to an ability to generate high levels of horizontal force and power. The acceleration characteristics presented in this study could be a result of the individual movement and positional demands of each code.
Rugby league is a team sport in which players engage in repeated high-intensity exercise involving frequent collisions. Recent research, much of which has involved global positioning system (GPS) technology, has provided coaches and sport scientists with a deeper understanding of match demands, particularly at the elite level. This has allowed for the development of training programmes that prepare players for the most intense contact and running demands likely to be experienced in competition. At the elite level, rugby league players have well-developed aerobic and anaerobic endurance, muscular strength and power, reactive agility, and speed. Upper- and lower-body strength and aerobic power are associated with a broad range of technical and sport-specific skills, in addition to a lower risk of injury. Significant muscle damage (as estimated from creatine kinase concentrations) and fatigue occurs as a result of match-play; while muscle function and perceptual fatigue generally return to baseline 48 h following competition, increases in plasma concentrations of creatine kinase can last for up to 5 days post-match. Well-developed physical qualities may minimise post-match fatigue and facilitate recovery. Ultimately, the literature highlights that players require a broad range of physical and technical skills developed through specific training. This review evaluates the demands of the modern game, drawing on research that has used GPS technology. These findings highlight that preparing players based on the average demands of competition is likely to leave them underprepared for the most demanding passages of play. As such, coaches should incorporate drills that replicate the most intense repeated high-intensity demands of competition in order to prepare players for the worst-case scenarios expected during match-play.
The purpose of this article was to compare strength, speed and power characteristics between playing position (forwards and backs) in elite rugby league players. A total of 39 first team players (height 183.8 ± 5.95 cm; body mass = 100.3 ± 10.7 kg; age 24 ± 3 years) from a National Rugby League club participated in this study. Testing included 10, 40m sprint times, sprint mechanics on an instrumented non-motorized treadmill, and concentric isokinetic hip and knee extension and flexion. Backs were observed to have significantly (p<0.05) lighter body mass (ES=0.98), were significantly faster (10m ES=1.26; 40m ES=1.61) and produced significantly greater relative horizontal force and power (ES=0.87 and 1.04) compared to forwards. However, no significant differences were found between forwards and backs during relative isokinetic knee extension, knee flexion, relative isokinetic hip extension, flexion, prowler sprints, sprint velocity, contact time or flight time. The findings demonstrate that backs have similar relative strength in comparison with forwards, but run faster over-ground and produce significantly greater relative horizontal force and power when sprinting on a non-motorized instrumented treadmill. Developing force and power in the horizontal direction may be beneficial for improving sprint performance in professional rugby league players.
Objectives
This study examined the influence of physical qualities on markers of fatigue and muscle damage following rugby league match-play.
Design
Between subjects design.
Methods
Twenty-one male youth rugby league players (age 19.2 ± 0.7 years; height 180.7 ± 5.6 cm; body mass 89.9 ± 10.0 kg) participated in the study. Yo-Yo intermittent recovery test (level 1), 3 repetition maximum back squat and bench press were assessed prior to 2 competitive fixtures. Neuromuscular fatigue (countermovement jump [CMJ] and plyometric push-up [PP]), and blood creatine kinase (CK) were assessed before and after match-play. During match-play, movements were recorded using microtechnology. Players were divided into high- and low-groups based on physical qualities.
Results
High Yo-Yo and squat performance resulted in greater loads during match-play (p < 0.05). There were larger reductions in CMJ power in the low Yo-Yo group at both 24 (ES = -1.83), and 48 h post-match (ES = -1.33). Despite greater internal and external match loads, changes in CMJ power were similar between squat groups. There were larger increases in blood CK in the low Yo-Yo group at 24 (73% vs. 176%; ES = 1.50) and 48 h post-match (28% vs. 80%; ES = 1.22). Despite greater contact loads, the high squat group exhibited smaller changes in blood CK post-match (ES = 0.25 to 0.39).
Conclusions
Post-match fatigue is lower in players with well developed high-intensity running ability, and lower body strength, despite these players having greater internal and external match loads.
Abstract The physical preparation of team sport athletes should reflect the degree to which each component of fitness is relied upon in competition. The aim of the study was therefore to establish the relationship between fitness-test data and game behaviours known or thought to be important for successful play in rugby union matches. Fitness-test measures from 510 players were analysed with game statistics, from 296 games within the 2007 and 2008 calendar years. Sprint times over 10, 20 and 30 m had moderate to small negative correlations (r) with line breaks (~0.26), metres advanced (~0.22), tackle breaks (~0.16) and tries scored (~0.15). The average time of 12 repeated sprints and percentage body fat in the forwards, and repeated sprint fatigue in the backs had moderate to small correlations with a measure of activity rate on and around the ball (-0.38, -0.17 and -0.17, respectively). These low correlations are partly due to uniformly high physical fitness as a result of selection pressures at the elite level and leave room for the identification of other key predictors. Nonetheless, physical conditioning programmes should be adapted to reflect the importance of speed, repeated sprint ability and body composition in the performance of key game behaviours during competition.
α-Actinin-3 deficiency occurs in approximately 16% of the global population due to homozygosity for a common nonsense polymorphism in the ACTN3 gene. Loss of α-actinin-3 is associated with reduced power and enhanced endurance capacity in elite athletes and nonathletes due to "slowing" of the metabolic and physiological properties of fast fibers. Here, we have shown that α-actinin-3 deficiency results in increased calcineurin activity in mouse and human skeletal muscle and enhanced adaptive response to endurance training. α-Actinin-2, which is differentially expressed in α-actinin-3-deficient muscle, has higher binding affinity for calsarcin-2, a key inhibitor of calcineurin activation. We have further demonstrated that α-actinin-2 competes with calcineurin for binding to calsarcin-2, resulting in enhanced calcineurin signaling and reprogramming of the metabolic phenotype of fast muscle fibers. Our data provide a mechanistic explanation for the effects of the ACTN3 genotype on skeletal muscle performance in elite athletes and on adaptation to changing physical demands in the general population. In addition, we have demonstrated that the sarcomeric α-actinins play a role in the regulation of calcineurin signaling.
Abstract The objective of the study was to describe an original approach to assessing individual workload during international rugby union competitions. The difference between positional groups and between the two halves was explored. Sixty-seven files from 30 French international rugby union players were assessed on a computerised player-tracking system (Amisco Pro (®) , Sport Universal Process, Nice, France) during five international games. Each player's action was split up into exercise and recovery periods according to his individual velocity threshold. Exercise-to-recovery (E:R) period ratios and acceleration were calculated. Results indicated that about 65% of exercise periods lasted less than 4 s; half of the E:Rs were less than 1:4, and about one-third ranged between 1 and 1:4 and about 40% of exercise periods were classified as medium intensity. Most acceleration values were less than 3 m·s(-2) and started from standing or walking activity. Back row players showed the highest mean acceleration values over the game (P < 0.05). No significant decrease in physical performance was seen between the first and second halves of the games except for back rows, who showed a significant decrease in mean acceleration (P < 0.05). The analysis of results emphasised the specific activity of back rows and tended to suggest that the players' combinations of action and recovery times were optimal for preventing large decrease in the physical performance.
No study has investigated the influence of field position and phase of play on the physical demands of match-play in professional rugby league forwards. We investigated the physical demands placed on forwards in elite rugby league matches, with special reference to how these demands differed between attack and defence, and in different field positions.
Cohort study.
Twenty-two rugby league players (26±3 years) from the same professional club participated in this study. Global positioning system (GPS) analysis was completed during 23 matches. Video footage was synchronised with the GPS files and coded for the time spent in attack and defence, and in one of three different field positions (0-30m, 31-70m, 71-100m).
The physical demands of defence were consistently greater than attack. Moderate to large differences (ES=0.62-1.41) were found between defence and attack for distance covered (109±16m/min vs. 82±12m/min), low speed distance (104±15m/min vs. 78±11m/min), frequency of collisions (1.9±0.7/min vs. 0.8±0.3/min), and repeated high-intensity effort bouts (1 every 4.9±5.1min vs. 1 every 9.4±6.1min). The running demands and frequency of repeated high-intensity effort bouts were greater when defending in the opposition's 30m zone (i.e. 71-100m), with repeated high-intensity effort bouts also occurring more frequently when defending the team's own try-line and when attacking the opposition's try-line.
Specific training drills designed to replicate the attacking and defensive demands of different field positional zones are likely to be effective in preparing players for the most demanding activities that occur in professional rugby league match-play.
There is currently limited information on whether pacing occurs during rugby league match-play. In addition, to date no research has investigated whether pacing strategies differ between winning and losing teams. This study investigated the pacing strategies of whole game and interchanged rugby league players. Furthermore, we investigated the pacing strategies of winning and losing teams. Fifty-two rugby league players, from a sample of 11 teams competing in a semi-elite competition, underwent global positioning system analysis. Performances were divided into match quartiles for whole-game and interchanged players. Total distance, including low-and high-speed distances, and repeated high-intensity effort bouts were recorded. The total and low-speed distance covered across all quartiles of the match, but specifically quartile 1 and 8, were greater for interchanged players than whole-game players. The match outcome differentially affected the pacing strategies of whole-game and interchanged players. Whole-game players from winning teams set a higher pacing strategy than whole-game players from losing teams (ES = 1.03 ± 0.77, 96%, very likely), while interchanged players from losing teams demonstrated a greater 'end-spurt' than interchanged players from winning teams (ES = 0.60 ± 0.52, 96%, very likely). The pacing strategies of interchanged players were higher than whole-game players, irrespective of playing position. The results of this study suggest that pacing strategies differ between interchanged and whole-game rugby league players. Furthermore, our results demonstrate a different pacing strategy between winning and losing teams. These findings suggest that physical preparation for rugby league matches, and recovery from these matches, should be individualized for whole game and interchanged players. Finally, performing physically intense training on a regular basis is likely to develop the physical and mental qualities required to regularly compete at higher playing intensities.
Objectives: The purpose of the study was to quantify the positional movement patterns of professional Rugby Union players competing in the English Premiership. Design: A cross sectional design was used. Setting: Field based data collection of one professional rugby union club during six league matches. Participants: An incidental sample of 35 professional rugby players with an age range of 20-34 years. Method: Recordings of the positional demands, taken from ten image recognition sensors, were coded for the specified high (HI) and low intensity (LI) tasks. Work-to-rest ratios were also calculated. Statistical assessment used an independent groups one-way ANOVA with post-hoc Scheffe test. Results: For all HI and LI activities there were significant position-related differences (P<0.05). In HI activities there were a range of different post-hoc Scheffe outcomes. The Props sprinted 1±1 time during a game while the Outside Backs sprinted 14±5 times. There were fewer post-hoc differences for the LI activities. For example, the Props jogged 325±26 times and the Outside Backs jogged 339±45 times. There was no significant position-related difference in the work-to-rest ratios for the quantity of HI and LI activities (P>0.05). There was, however, a significant positional difference when comparing the work to rest ratio for time spent in HI and LI activities (P<0.05). The Loose Forwards had the least amount of recovery with a work to rest time ratio, in seconds, of 1:7.5 s. The Outside Backs had the most amount of recovery, 1:14.6 s. Conclusions: There were clear positional differences in the quantity and time spent in rugby specific demands. These differences are most obvious in the HI activities of the game and included position-specific differences within both the Forward and Backs units.
Abstract This study examined the influence of match-related fatigue on physical and technical skill performance in ball playing positions at two different levels of rugby league competition. Time-motion analyses were performed using global positioning systems from 6 elite National Rugby League (NRL) and 11 junior elite National Youth Competition (NYC) players from 45 matches. A standardised 5-point technical coding criteria was used to qualitatively assess skill involvements during match-play. The distance travelled in the 0-5 and 40-45 min period were significantly higher compared to the 30-35, 35-40, 70-75 and 75-80 min periods (P < 0.001). Skill rating and involvements were higher in the 0-5 and 40-45 min compared to 70-75 and 75-80 min periods (P < 0.001 and P < 0.001, respectively).There was no significant difference in the number of physical collisions between the 5-min periods (P = 0.051). Following the peak 5-min bout of exercise intensity there were reductions in distance (P < 0.001), quality of skill involvements (P < 0.001), number of involvements (P < 0.001) and collisions (P < 0.001). Elite NRL and NYC "ball players" exhibit reductions in physical performance towards the end of matches and following brief periods of intense exercise. There also appears to be a reduction in technical performance for NRL and NYC ball players, which may be attributable to match-related fatigue.
Aim:
The aim of this paper was to investigate the changes over time in anthropometric parameters of young and adult rugby players in France.
Methods:
Age, mass and height were collected for 2051 French elite rugby players participating in the championship during the 1988-1989 and the 2008-2009 seasons. The same variables were collected for the best 145 juniors (under 21 years) and 448 U15 (under 15 years) French players for these seasons. Changes in anthropometric parameters were compared according to age, category (back vs. forwards) and season.
Results:
Over 20 years, adult French rugby backs and forwards have become heavier by 12 kg and 12.3 kg, taller by 5.4 cm and 2.9 cm, respectively. Junior players also became taller and heavier, 6 cm and 9.9 kg for backs and 4.4 cm and 11.1 kg for forwards. U15 backs have gained 5.1 cm and 6.5 kg, and forwards earned 4.7 cm and 4.7 kg.
Conclusion:
Rugby players have become taller and heavier. Their current morphology is the product of a long process of competition and selection. This study demonstrates that this selection of the "large sizes" is already present at a young age.
This study investigated the physical qualities that discriminated state-based rugby league players competing for selection in a semi-professional rugby league team, and determined the relationship between tests of physical qualities and physical match performance in these players. Thirty-two rugby league players (mean ± SD age, 24 ± 3 yr) from a Queensland Cup rugby league squad participated in this study. Players performed tests of upper-body strength (3 repetition maximum [RM] bench press; 3 RM weighted chin-up), upper-body strength-endurance (body-mass maximum repetition bench press), lower-body strength (3 RM squat), lower-body power (vertical jump), and prolonged high-intensity intermittent running ability (Yo-Yo intermittent recovery test, level 1). Global positioning system data, sampling at 10 Hz, were collected during 5 Queensland Cup rugby league matches. Selected players had greater (p<0.05) 3RM squat, 3RM chin-up, body-mass bench press, vertical jump, and Yo-Yo intermittent recovery test performances than non-selected players. After controlling for playing position, players with better 3RM squat performances covered greater total distances (r = 0.98, p<0.05) including greater distances at low (r = 0.98, p<0.05) and high (r = 0.97, p<0.05) speeds. Significant associations (r = 0.96, p<0.05) were also found between 3RM squat performances and the number of repeated high-intensity effort bouts performed in competition. These findings highlight the importance of lower-body strength, upper-body strength and endurance, and prolonged high-intensity intermittent running ability to team selection in semi-professional rugby league. Furthermore, our findings suggest that well-developed lower-body strength contributes to effective physical match performance in semi-professional rugby league players.
Genetic polymorphism is suggested to be associated with human physical performance. The angiotensin I-converting enzyme insertion/deletion (ACE I/D) polymorphism and the α-actinin-3 gene (ACTN3) R577X polymorphism have been most widely studied for such association analysis. However, the findings are frequently heterogeneous. We aim to summarize the associations of ACE I/D and ACTN3 R577X with sport performance by means of meta-analysis.
We systematically reviewed and quantitatively summarized published studies, until October 31, 2012, on relationship between ACE/ACTN3 genetic polymorphisms and sports performance, respectively.
A total of 366 articles on ACE and 88 articles on ACTN3 were achieved by literature search. A significant association was found for ACE II genotype compared to D allele carriage (DD+ID) with increased possibility of physical performance (OR, 1.23; 95% CI, 1.05-1.45). With respect to sport discipline, the II genotype was found to be associated with performance in endurance athletes (OR, 1.35; 95% CI, 1.17-1.55). On the other hand, no significant association was observed for ACTN3 RR genotype as compared to X allele carriage (XX+RX) (OR, 1.03; 95% CI, 0.92-1.15). However, when restricted the analyses to power events, a significant association was observed (OR, 1.21; 95% CI, 1.03-1.42).
Our results provide more solid evidence for the associations between ACE II genotype and endurance events and between ACTN3 R allele and power events. The findings suggest that the genetic profiles might influence human physical performance.
This study investigated the influence of playing standard, and winning and losing on the physical demands of elite rugby league match-play. Twenty-two elite rugby league players participated in this study. Global positioning system data was collected during 16 rugby league matches. Players covered significantly greater (P≤0.05) absolute and relative distance at high speeds when playing against Bottom 4 teams than when competing against Top 4 teams. The total distance per minute of match-play, and relative distance at low speeds were greater when matches were won. In addition, a greater absolute and relative number of maximal accelerations, and repeated high-intensity effort bouts were performed when players were competing in winning teams than when competing in losing teams. The mean and maximum number of efforts in a repeated high-intensity effort bout was also higher in winning teams, although the recovery between efforts was shorter in losing teams. Moderate (7-17 points) and large (≥18 points) winning margins were associated with greater relative distances covered and distances covered at low speeds than small winning margins. No meaningful differences were found in the physical demands between small, moderate, and large losing margins. The results of this study demonstrate that the physical demands of rugby league are greater when winning than when losing, and when competing against lower-ranked teams. Furthermore, larger winning margins are associated with greater physical demands than small and moderate winning margins, with these physical demands in turn, greater than losing margins of any magnitude. These findings suggest that the competitive advantage of successful elite rugby league teams is closely linked to their ability to maintain a higher playing intensity than their less successful counterparts.
Previous investigators have reported significant relationships between tests of physical qualities and physical match performance in high-intensity intermittent team sport (e.g. soccer) players. While rugby league requires competitors to perform high-intensity running, unlike most other high-intensity intermittent team sports, the physical demands are significantly increased through the large amounts of tackling, wrestling, and grappling that players are required to perform during match-play. This study investigated the relationship between tests of physical qualities and match performance in professional rugby league players, and determined whether running capacities were associated with the collision and repeated high intensity effort demands of match-play. Thirty-eight elite rugby league players (mean ± SD age, 23.1 ± 2.7 yr) performed tests of repeated sprint ability (6 x 20 m sprints on a 20 s cycle), prolonged high-intensity intermittent running ability (8 x 12 s shuttle sprints on a 48 s cycle), and estimated maximal aerobic power (multi-stage fitness test). Global positioning system data were collected during 16 professional rugby league matches. Players with better prolonged high-intensity intermittent running ability covered greater total distance and greater distance in high-speed running during match-play. However, inconsistent relationships were found between tests of running abilities and other match performance variables, with prolonged high-intensity running ability (negative), maximal aerobic power (positive), and repeated-sprint ability (no relationship) differentially associated with the total number of collisions and repeated high-intensity effort bouts performed in competition. These findings demonstrate the importance of prolonged high-intensity running ability to the match running performance of elite rugby league players, but also highlight the need for game-specific conditioning to prepare players for the high-intensity collision, and repeated-effort demands of the game.
Abstract This study investigated the association between explosive force production during isometric squats and athletic performance (sprint time and countermovement jump height). Sprint time (5 and 20 m) and jump height were recorded in 18 male elite-standard varsity rugby union players. Participants also completed a series of maximal- and explosive-isometric squats to measure maximal force and explosive force at 50-ms intervals up to 250 ms from force onset. Sprint performance was related to early phase (≤100 ms) explosive force normalised to maximal force (5 m, r = -0.63, P = 0.005; and 20 m, r = -0.54, P = 0.020), but jump height was related to later phase (>100 ms) absolute explosive force (0.51 < r < 0.61; 0.006 < P < 0.035). When participants were separated for 5-m sprint time (< or ≥ 1s), the faster group had greater normalised explosive force in the first 150 ms of explosive-isometric squats (33-67%; 0.001 < P < 0.017). The results suggest that explosive force production during isometric squats was associated with athletic performance. Specifically, sprint performance was most strongly related to the proportion of maximal force achieved in the initial phase of explosive-isometric squats, whilst jump height was most strongly related to absolute force in the later phase of the explosive-isometric squats.
The purpose of the present study was to examine the reliability and sensitivity of three ecologically valid repeated high intensity exercise (RHIE) tests for professional rugby league and rugby union players. A further purpose was to investigate the relationship between RHIE performance and measures of speed (20m sprint) and high-intensity intermittent running ability (yo-yo intermittent recovery test). Thirty six rugby union and rugby league players were separated into three equal groups based on playing position: backs, rugby league (RL) forwards and rugby union (RU) forwards. Test-retest reliability was assessed by comparing total sprint time over nine sprints during two identical testing sessions. The intra-class correlation coefficients (ICC) for total sprint time were moderate to high (0.82, 0.97 and 0.94) and coefficient of variation (CV) low (4.2%, 1.4%, and 0.6%) for the backs, RL forwards and RU forwards tests, respectively. However, sprint performance decrement scores were poorer, with ICC and CV of 0.78, 0.86 and 0.88 and 49.5%, 48.2%, and 35.8% for the backs, RL forwards and RU forwards, respectively. Total sprint times for the backs, RL forwards, and RU forwards decreased over the three tests by 0.54 s, 0.53 s and 2.09 s respectively. Changes in RHIE total sprint time were moderately related to changes in 20 m sprint times (T1 to T2; r = 0.63, T2 to T3; r = 0.69 and T1 to T3; r = 0.63; all p < 0.05), but not yo-yo intermittent recovery test performances. The present study has shown that the designed rugby league and rugby union RHIE tests have moderate to high reliability and produce significant improvements over a training period when total sprint times are compared.
Success in rugby league football seems heavily reliant on players possessing an adequate degree of various physical fitness qualities, such as strength, power, speed, agility, and endurance, as well as the individual skills and team tactical abilities. The purpose of this study was to describe and compare the lower body strength, power, acceleration, maximal speed, agility, and sprint momentum of elite first-division national rugby league (NRL) players (n = 20) to second-division state league (SRL) players (n = 20) players from the same club. Strength and maximal power were the best discriminators of which players were in the NRL or SRL squads. None of the sprinting tests, such as acceleration (10-m sprint), maximal speed (40-m sprint), or a unique 40-m agility test, could distinguish between the NRL or SRL squads. However, sprint momentum, which was a product of 10-m velocity and body mass, was better for discriminating between NRL and SRL players as heavier, faster players would possess better drive forward and conversely be better able to repel their opponents'drive forward. Strength and conditioning specialists should therefore pay particular attention to increasing lower body strength and power and total body mass through appropriate resistance training while maintaining or improving 10-m sprint speed to provide their players with the underlying performance characteristics of play at the elite level in rugby leagues.
To investigate the evolution of anthropometric characteristics in World Cup rugby players and identify elements associated with performance.
Age, weight and height were collected for 2692 World Cup rugby players as well as rankings in each World Cup, and collective experience of winners, finalists, semifinalists and quarter finalists in comparison to the rest of the competitors. Anthropometric parameters were compared according to age and position (back and forwards).
From 1987 to 2007, forwards and backs have become heavier by 6.63 and 6.68 kg and taller by 0.61 and 1.09 cm, respectively. The collective experience of the forwards' pack is a value increasing with the final ranking attained, as well as the weight of forwards and the height of backs.
For all Rugby World Cups, the highest performing teams have the tallest backs and heaviest forwards with the highest percentage of collective experience.
The influence of contraction type on the human ability to use the torque capacity of skeletal muscle during explosive efforts has not been documented. Fourteen male participants completed explosive voluntary contractions of the knee extensors in four separate conditions: concentric (CON) and eccentric (ECC); and isometric at two knee angles (101°, ISO101 and 155°, ISO155). In each condition, torque was measured at 25 ms intervals up to 150 ms from torque onset, and then normalized to the maximum voluntary torque (MVT) specific to that joint angle and angular velocity. Explosive voluntary torque after 50 ms in each condition was also expressed as a percentage of torque generated after 50 ms during a supramaximal 300 Hz electrically evoked octet in the same condition. Explosive voluntary torque normalized to MVT was more than 60 per cent larger in CON than any other condition after the initial 25 ms. The percentage of evoked torque expressed after 50 ms of the explosive voluntary contractions was also greatest in CON (ANOVA; p < 0.001), suggesting higher concentric volitional activation. This was confirmed by greater agonist electromyography normalized to M(max) (recorded during the explosive voluntary contractions) in CON. These results provide novel evidence that the ability to use the muscle's torque capacity explosively is influenced by contraction type, with concentric contractions being more conducive to explosive performance due to a more effective neural strategy.
The purpose of this study was to investigate the sprinting demands of National Rugby League (NRL) competition and characterize the sprinting patterns of different rugby league playing positions. Thirty-seven elite rugby league players (mean ± SE age: 23.6 ± 0.5 years) underwent global positioning satellite analysis during 104 NRL appearances. The majority (67.5%) of sprint efforts were across distances of <20 m. The most common sprint distance for hit-up forwards was 6-10 m (46.3%). Outside backs had a greater proportion (33.7%) of sprint efforts over distances of ≥21 m. The proportion of sprint efforts over 40 m or greater for hit-up forwards, wide running forwards, adjustables, and outside backs was 5.0, 7.4, 5.0, and 9.7%, respectively. Of the sprints performed, approximately 48.0% involved contact, approximately 58.0% were preceded by forward locomotion (forward walking, jogging, or striding), whereas over 24.0% occurred from a standing start. Hit-up forwards more commonly sprinted from a standing start, or after lateral movement, whereas forward striding activities more commonly preceded sprint efforts for the adjustables and outside backs. The majority of sprint efforts were performed without the ball (78.7 vs. 21.3%). Most sprint efforts (67.5%) were followed by a long recovery (i.e., ≥5 minutes). Outside backs had the greatest proportion (76.1%) of long duration recovery periods and the smallest proportion (1.8%) of short duration recovery periods (i.e., <60 seconds) between sprints. The results of this study demonstrate differences among rugby league playing positions for the nature of sprint efforts and the typical distances covered during these efforts. Furthermore, the activities preceding and the recovery periods after sprint efforts were different among playing positions. These findings suggest that rugby league sprint training should be tailored to meet the individual demands of specific playing positions.
Argus, CK, Gill, ND, and Keogh, JWL. Characterization of the differences in strength and power between different levels of competition in rugby union athletes. J Strength Cond Res 26(10): 2698-2704, 2012-Levels of strength and power have been used to effectively discriminate between different levels of competition; however, there is limited literature in rugby union athletes. To assess the difference in strength and power between levels of competition, 112 rugby union players, including 43 professionals, 19 semiprofessionals, 32 academy level, and 18 high school level athletes, were assessed for bench press and box squat strength, and bench throw, and jump squat power. High school athletes were not assessed for jump squat power. Raw data along with data normalized to body mass with a derived power exponent were log transformed and analyzed. With the exception of box squat and bench press strength between professional and semiprofessional athletes, higher level athletes produced greater absolute and relative strength and power outputs than did lower level athletes (4-51%; small to very large effect sizes). Lower level athletes should strive to attain greater levels of strength and power in an attempt to reach or to be physically prepared for the next level of competition. Furthermore, the ability to produce high levels of power, rather than strength, may be a better determinate of playing ability between professional and semiprofessional athletes.
In this study, we investigated the relationship between physiological, anthropometric, and skill qualities and playing performance in professional rugby league players. Fifty-eight high-performance rugby league players underwent measurements for anthropometry (height, body mass, sum of seven skinfolds), physiological (speed, change of direction speed, lower body muscular power, repeated-sprint ability, prolonged high-intensity intermittent running ability, and estimated maximal aerobic power), technical skill (tackling proficiency, draw and pass proficiency), and perceptual skill (reactive agility, pattern recall, pattern prediction) qualities. National Rugby League matches were coded for attacking (e.g. line breaks, try assists, etc.) and defensive (e.g. missed tackles, tackling efficiency, etc.) statistics commonly used to assess rugby league playing performance. The number of line break assists was significantly associated (P < 0.05) with greater playing experience (r = 0.36), dual-task draw and pass proficiency (r = 0.54), reactive agility (r = 0.29), and pattern recall (r = 0.32) and prediction (r = 0.28) ability, while faster speed over 40 m (r = -0.42) was associated (P < 0.05) with a higher number of tries scored. Greater age and playing experience, better lower body muscular power, and faster 10 m and 40 m speed were significantly associated (P < 0.05) with the number of tackle attempts (positive), tackles completed (positive), and proportion of missed tackles (negative). These findings demonstrate that well-developed physical and skill qualities are associated with effective playing performance in National Rugby League players.
This study investigated the relative importance of physiological, anthropometric, and skill qualities to team selection in professional rugby league. Eighty-six high performance rugby league players underwent measurements of anthropometric (height, body mass, sum of seven skinfolds), physiological (speed, change of direction speed, lower body muscular power, repeated-sprint ability, prolonged high-intensity intermittent running ability, and maximal aerobic power), technical skill (tackling proficiency, draw and pass proficiency), and perceptual skill (reactive agility, pattern recall, pattern prediction) qualities. A linear discriminant analysis was also conducted comparing those players successful in gaining selection into the professional National Rugby League team with those not selected to determine which, if any, of these qualities could predict selection. Players selected to play in the first National Rugby League game of the season were older, more experienced, leaner, had faster 10 m and 40 m sprint times, and superior vertical jump performances, maximal aerobic power, tackling proficiency and dual-task draw and pass ability than non-selected players. Skinfold thickness and dual-task draw and pass proficiency were the only variables that contributed significantly (P < 0.05) to the discriminant analysis of selected and non-selected players. These findings suggest that selected physiological, anthropometric, and skill qualities may influence team selection in professional rugby league.
To investigate the physical demands of professional rugby league match-play using microtechnology, and to compare these demands with typical training activities used to prepare players for competition.
Prospective cohort study.
Thirty elite rugby league players participated in this study. Seven hundred and eighty-six. training data sets and 104 data sets from National Rugby League matches were collected over one playing season. Movement was recorded using a commercially available microtechnology unit (minimaxX, Catapult Innovations), which provided information on speeds, distances, accelerations, physical collisions and repeated high-intensity efforts.
Mean distances covered during match-play by the hit-up forwards, wide-running forwards, adjustables, and outside backs were 3,569 m, 5,561 m, 6,411 m, and 6,819 m, respectively. Hit-up forwards and wide-running forwards were engaged in a greater number of moderate and heavy collisions than the adjustables and outside backs, and more repeated high-intensity effort bouts per minute of play (1 bout every 4.8-6.3 min). The physical demands of traditional conditioning, repeated high-intensity effort exercise, and skill training activities were all lower than the physical demands of competition.
These results demonstrate that absolute distances covered during professional rugby league matches are greater for outside backs, while the collision and repeated high-intensity effort demands are higher for hit-up forwards and wide-running forwards. The specific physical demands of competitive play, especially those demands associated with collisions and repeated high-intensity efforts, were not well matched by those observed in traditional conditioning, repeated high-intensity effort exercise, and skills training activities. Further research is required to investigate whether modifications need to be made to these training activities to better prepare players for the demands of National Rugby League competition.
Objectives:
To retrospectively compare the longitudinal physical development of junior rugby league players between the Under 13 and 15 age categories in relation to their adult career attainment outcome.
Design:
Retrospective longitudinal design.
Methods:
Fifty-one former junior rugby league players were retrospectively grouped according to their career attainment outcome as adults (i.e., amateur, academy or professional). As juniors, players undertook a physical testing battery on three consecutive annual occasions (Under 13s, 14s, 15s) including height, body mass, sum of four skinfolds, maturation, vertical jump, medicine ball chest throw, 10-60m sprint, agility 505 and estimated V˙O2max .
Results:
Future professional players were younger than academy players with a greater estimated V˙O2max compared to amateur players. Between Under 13s and 15s, professional players (5.8±2.5cm) increased sitting height more than amateur (4.4±2.1cm) and academy (4.1±1.4cm) players. Logistic regression analyses demonstrated improvements in sitting height, 60m sprint, agility 505 and estimated V˙O2max between amateur and professional players with a high degree of accuracy (sensitivity=86.7%, specificity=91.7%).
Conclusions:
Findings demonstrate that the development of anthropometric, maturational and physical qualities in junior rugby league players aged between 13 and 15 years contributed to adulthood career attainment outcomes. Results suggest that age, maturity and size advantages, commonly observed in adolescent focused talent identification research and practice, may not be sensitive to changes in later stages of development in order to correctly identify career attainment. Practitioners should identify, monitor and develop physical qualities of adolescent rugby league players with long-term athlete development in mind.
Purpose:
The purpose of this investigation was to examine the relationships between isometric mid-thigh pull (IMTP) force and strength, sprint, and agility performance in collegiate rugby union players.
Methods:
Fifteen members of a champion-level university's club rugby union team (mean±SD: 20.67±1.23y, 1.78±0.06m, and 86.51±14.18kg) participated in this investigation. One repetition-maximal (1RM) squat, IMTP, speed (40m sprint), and agility (pro-agility test and T-test) were performed during three separate testing sessions. Rate of force development (RFD) and force output at 30ms, 50ms, 90ms, 100ms, 150ms, 200ms and 250ms of IMTP, as well as the peak value were determined. Pearson product-moment correlation analysis was used to examine the relationships between these measures.
Results:
Performance in the 1RM squat was significantly correlated to the RFD between 90ms - 250ms from the start of contraction (r's ranging from 0.595 - 0.748), and peak force (r = 0.866, p<0.05). 1RM squat was also correlated to force outputs between 90ms and 250ms (r's ranging from 0.757 - 0.816, p<0.05). Sprint time over the first 5m in the 40m sprint was significantly (p<0.05) correlated with peak RFD (r = -0.539) and RFD between 30ms and 50ms (r's = -0.570 and -0.527, respectively). Time for the pro-agility test was correlated with peak RFD (r = -0.523, p<0.05) and RFD between 30ms - 100ms (r's ranging from -0.518 and -0.528, p's<0.05).
Conclusions:
Results of this investigation indicate that IMTP variables are significantly associated with strength, agility and sprint performance. Future studies should examine IMTP as a potential tool to monitor athletic performance during the daily training of rugby union players.
To investigate the impact forces of collision events during both attack and defence within elite rugby league match-play, and to compare the collision profiles between playing positions.
Twenty-six elite rugby league players participated in this study. Player collisions were recorded using an integrated accelerometer within global positioning system units (SPI-Pro X, GPSports). Impact forces of collisions in attack (hit-ups) and defence (tackles) were analysed from 359 files from outside backs (n=78), adjustables (n=97), wide-running forwards (n=136) and hit-up forwards (n=48) over one National Rugby League season.
Hit-up forwards were involved in 0.8 collisions per minute, significantly greater than all other positional groups (wide-running forwards p=0.050, adjustables p=0.042 and outside backs p=0.000). Outside backs experienced 25% fewer collisions per minute than hit-up forwards. Hit-up forwards experienced a collision within the two highest classifications of force (≥10G) every 2.5 minutes of match-play compared to one every 5 and 9 minutes for adjustables and outside backs, respectively. Hit-up forwards performed 0.5 tackles per minute of match-play, five times that of outside backs (ES=1.90; 95% CI (0.26,3.16)) and 0.2 hit-ups per minute of match-play, twice as many as adjustables.
During a rugby league match, players are exposed to a significant number of collision events. Positional differences exist with hit-up and wide-running forwards experiencing greater collision events than adjustables and outside backs. Although these results may be unique to the individual team's defensive and attacking play strategies, they are indicative of the significant collision profiles in professional rugby league.
Numerous studies have highlighted differences between playing levels and positions in rugby union; however few studies have investigated longitudinal progressions of body composition and physical performance. Between-player differences and within-player changes in body composition, strength, power, speed, and repeated sprint ability, from 1161 New Zealand rugby union players from 2004-2007, were estimated using a mixed modelling procedure. Props had the highest mass, percent body fat, strength and slowest speed times compared to the other positions, while outside backs had the fastest speed time and lowest percent body fat. For most measures there were small to moderate differences (range 1.1% - 14%) between players selected and not selected for provincial teams, and small to large differences (range 1.8% - 15%) between provincial and Super Rugby (professional) players. The faster 20-m sprint times in international compared to Super Rugby players was small in magnitude for both the forwards (1.9%) and backs (2.2%). The average annual improvements were small to moderate for strength (range 2.1% - 15%) and small for repeated sprint ability within the lower playing levels (∼1.5%). Small increases occurred in lower body strength (∼7.0%) as players moved from Super Rugby to provincial competition. Small decreases in sprint time (∼1.6%) and small increases in strength (∼6.3%) occurred as players moved from Super Rugby to mid-year international competition. The differences between levels in performance provide level-specific characteristics from Super Rugby and below, but international players may be selected due to greater skill and experience. Changes in physical performance between competitions may be a result of reduced training loads due to regular high-intensity matches and greater travel involved in the Super Rugby competition.
The purpose of this study was to investigate the effect of different volumes of plyometric exercise (i.e., 100, 200, or 300 hurdle jumps) on acute strength and jump performance as well as on the acute hormonal and lactate responses in rugby players. Eleven young male elite rugby players (age, 23.5 ± 0.9 years; height, 173 ± 4.8 cm) volunteered for the study. Maximal isometric peak torque (PT), maximal rate of force development (RFD), and squat jump (SJ) and drop jump (DP) performance were assessed before and 5 minutes, 8 hours, and 24 hours after 100, 200, or 300 jumps. In addition, total testosterone, cortisol, and lactate were measure before and after the three different plyometric exercise volumes. There were significant decreases in the PT (P<0.02) and maximal RFD (P<0.001) 5 minutes, 8 hours, and 24 hours after 100, 200 and 300 jumps, with no differences between the exercise volumes. Additionally, there were significant decreases in the SJ (P<0.001) and DJ (P<0.01) performances 24 hours after 100, 200, and 300 jumps, with no differences between the exercise volumes. However, there were significant increases in the total testosterone (P<0.001), cortisol (P<0.05), and lactate (P<0.001) after 100, 200, and 300 jumps, with no differences between the exercise volumes. All plyometric exercise volumes (100, 200, and 300 jumps) resulted in similar neuromuscular, metabolic, and hormonal responses.
Alternative measures of muscle size, strength, and power to those used in previous studies could help resolve the controversy surrounding associations between polymorphisms of the angiotensin-I converting enzyme (ACE) and α-actinin-3 (ACTN3) genes and skeletal muscle phenotypes, and the responses to resistance training (RT). To this end, we measured quadriceps femoris muscle volume (V(m) ), physiological cross-sectional area (PCSA), maximum isometric force (F(t) ), specific force (F(t) per unit PCSA), maximum isoinertial strength (1-RM), and maximum power (W(max) ; n = 40) before and after 9-week knee extension RT in 51 previously untrained young men, who were genotyped for the ACE I/D and ACTN3 R577X polymorphisms. ACTN3 R-allele carriers had greater V(m) , 1-RM, and W(max) than XX homozygotes at baseline (all P < 0.05), but responses to RT were independent of ACTN3 genotype (all P > 0.05). Muscle phenotypes were independent of ACE genotype before (all P > 0.05) and after RT (all P > 0.01). However, people with the "optimal" ACE+ACTN3 genotype combination had greater baseline 1-RM and W(max) compared to those with the "suboptimal" profile (both P < 0.0125). We show for the first time that the ACTN3 R577X polymorphism is associated with human V(m) and (independently and in combination with the ACE I/D polymorphism) influences 1-RM and W(max) .
Abstract The aim of the study was to evaluate changes in the stature, body mass, age and number of players by playing position in the first team squads of English Premiership rugby union teams from 2002 to 2011. Medical personnel at each club reported the individual data for every first team squad player. The average annual number of players included in the study was 485.2 players per season (standard deviation: 58.0). The mean stature of players in all positions increased in the period 2002 to 2011 but statistically significant trends (P < 0.01) were only observed at fly half and prop. While the mean body mass of players increased in most positions only fly half and back row players showed statistically significant (P < 0.01) upward trends. Apart from second row forwards, the average age of players in all positions decreased but this trend was only significant (P < 0.01) at prop. The numbers of registered players in every position increased but these trends were only significant (P < 0.01) at prop. English Premiership professional rugby players are generally getting taller, heavier and younger but statistically significant changes were limited to fly halves (taller and heavier), props (taller and younger) and back row forwards (heavier).
Unlabelled:
In rugby union, published analyses of actions and movements of players during matches have been limited to small samples of games at regional or national level.
Objectives:
To analyse movements and activities of players in international rugby union matches with a sample size sufficient to clearly delineate positional roles.
Design:
Observational study.
Methods:
Actions of 763 players were coded from video recordings of 90 international matches played by the New Zealand national team (the All Blacks) from 2004 to 2010. Movements of players were coded for 27 of these matches via a semi-automated player-tracking system. Movements and activities of all players from both teams were coded.
Results:
Cluster analysis of activities and time-motion variables produced five subgroups of forwards (props, hookers, locks, flankers, Number 8 forwards) and five subgroups of backs (scrum-half, fly-half, midfield backs, wings and fullbacks). Forwards sustained much higher contact loads per match than backs, via scrums, rucks, tackles and mauls. Mean distance covered per match ranged from 5400 to 6300m, with backs generally running further than forwards. There were marked differences between positional groups in the amount of distance covered at various speeds. The amount of play per match varies by position due to differences in rates at which players are substituted.
Conclusions:
The distance covered by players at relatively fast running speeds (in excess of 5ms(-1)) appears to be higher during international matches than when competing at lower levels of the professional game. The specific match demands for positional groups need to be considered when managing player workloads.
In 2007, the first common genetic variants were identified, which undoubtedly affect our susceptibility to obesity. These variants are located in the fat mass and obesity-associated gene FTO. Since then, over 50 loci for common obesity have been identified. As the research on these loci is still at an early stage, there is a great need to review, for clarification purposes, the current research on FTO, as this is likely to influence future studies. Based on the current knowledge, FTO seems to be directly involved in the regulation of energy intake, but there is an urgent need for the identification of regulatory polymorphisms. Thus, herein, we discuss current knowledge and highlight putative functional regions in FTO based on published data and computer-based analysis.
A total of 31,655 tackles in 48 professional rugby league matches were coded from video for height and direction of tackle on the ball carrier. Injuries were recorded by team medical staff for injury date, time, site, type, mechanism, severity, and player position. Tackle-related injuries were most frequently the result of two tacklers being involved in tackling the ball carrier from the side at shoulder or midtorso body levels. The ball carrier had a higher injury rate when tackled from behind his visual field at shoulder height and in the fourth quarter of matches. Tacklers had a higher risk of injury when tackling from the side of the ball carrier, as the first tackler, and in the third quarter of matches. Coaches should focus on practicing correct technique during tackling with two or more tacklers and when tackling in the ball carrier's blind vision area.