Article

Activity and Recovery Profiles of State-of-Origin and National Rugby League Match-Play

Authors:
  • Gabbett Performance Solutions
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Abstract

State-of-Origin is the highest standard of rugby league competition played anywhere in the world. This study investigated the activity profiles of State-of-Origin and compared them against regular National Rugby League (NRL) fixture matches. Video footage from State-of-Origin and NRL matches were coded for activity and recovery cycles. Time when the ball was continuously in play was considered activity, while any stoppages during matches were considered recovery. Ball-in-play periods in matches of different playing standards were analyzed by comparing State-of-Origin matches, NRL matches (with representative players available), and NRL matches (with representative players unavailable). The mean, maximum, and total ball-in-play time of State-of-Origin matches were longer than NRL matches (ES=≥0.75), with and without the availability of representative players. State-of-Origin matches were associated with a greater proportion (ES=≥1.54) of long duration (46 to 300 s) ball-in-play periods, and a smaller proportion (ES=≥1.69) of short duration (<45 s) ball-in-play periods than NRL matches when representative players were both available and unavailable for selection. When representative players were available for club selection, NRL matches were associated with a smaller proportion of short duration ball-in-play periods (ES=1.14) and a larger proportion of long duration ball-in-play periods (ES=0.89), compared to NRL matches when representative players were unavailable. The results of this study provide empirical support for the higher playing intensity of State-of-Origin matches in comparison to regular NRL fixture matches. Furthermore, these findings demonstrate the lower quality of NRL matches during the State-of-Origin period, when representative players are unavailable for selection for their club team. From a practical perspective, these results quantify the difference in activity profiles between State-of-Origin and NRL competitions, and demonstrate the need to prepare rugby league players to perform prolonged passages of high-intensity exercise during match-play.

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... In addition, no data exist to quantify the "worst-case" time durations of play at U17, U21 and senior level. Research that quantifies the differences in BIP and BOP of each competition would provide a better understanding of a potential gap between levels and further aid the development of game-specific activities (Gabbett, 2015a). Furthermore, knowledge of the "worst-case scenario" passages of play would assist coaches to condition players to undertake these maximal durations that occur in competition. ...
... In addition, the match duration is a significant differentiator among team sports and even within the same sport. An investigation of the duration demands of competition has been used to provide further insight into the physical demands of competition (Gabbett, 2012a(Gabbett, , 2015b(Gabbett, , 2015aSiegle and Lames, 2012a;Pollard et al., 2018). Although the match duration is guided by the playing rules, previous research has shown that the total match duration is a poor indicator of the actual match playing time (Collins, Doran and Reilly, 2010;Pollard et al., 2018). ...
... In study I, video footage was taken from the primary camera of the stadium, placed about 30 m above the pitch level (Siegle and Lames, 2012a). Matches (U21 and seniors) were selected if they were broadcast on TV and freely available in the public domain (Gabbett, 2015a). However, only highlights of the U17 matches were broadcasted on TV, so a request was made to the TV Company (TG4) for access to the full duration of each match, which were provided on DVDs. ...
Thesis
Hurling is one of the national sports played in Ireland. With 15 players on each team, the objective of this stick and ball game is to outscore your opponents. The demands of this sport are not well known. Time-motion analysis of the activity cycles of elite hurling was carried out using SportsCode analysis software, where the ball-in-play (BIP) and ball-out-of-play (BOP) cycles, the number and type of stoppage were analysed. The running variables (total distance, relative distance, distance covered at each intensity, number and length of sprints, number of entries and maximal relative intensities) were collected using GPS. Heart rate (HR) (peak [HRpeak] and mean [HRmean]) were recorded. The ball is only in play for 40%, 43% and 44% of the playing time in senior, U21 and U17 matches’ respectively. Senior matches were 11 min longer in actual match duration but no difference in the total BIP time was observed across all levels. A Shot at Goal and Free Attempted are the most frequent and longest stoppage type respectively at all levels. Elite players covered greater relative distance and relative walking distance and experienced a higher HRmean than sub-elite players. There was no difference between levels in relative jogging, high-speed running (HSR) and sprint distance (SD) and the number of entries HSR and sprinting. Elite senior hurlers covered greater total distance (TD), HSR and SD compared to U21s, U17s and sub-elite seniors. However, the number of sprints, the mean length of sprint, the maximal speed, HRmean and HRpeak were similar at all levels. In elite senior, the majority of sprints are < 20 m and occur between 22 km·h-1 and 80% of the players’ peak speed. Players at elite senior level are exposed to higher relative maximal intensities in TD, HSR and SD compared to data expressed per half and full game. Positional differences occur in TD, relative distance, HSR, SD between metrics. In addition, there were no positional differences in HRmean and HRpeak at each level, except at elite senior, where half-backs had a lower HRpeak than full-backs. Second half temporal decrements in TD, relative distance, HSR, HRmean and HRpeak are observed at all levels. The findings from the seven studies showed that hurling matches consist of a large number of short (< 30 s) BIP and BOP cycles. The similarity in the total BIP, the number and duration of stoppages, highlight the commonality among hurling matches at all levels. However, when transitioning to elite senior level, players are required to cover greater TD, relative distance, HSR and SD. The number and mean length of sprint are similar in elite senior, U21 and U17 matches, which emphasises the importance of sprinting no matter what the level. Even though the relative maximal intensities (TD, HSR and SD) only occur once in a game, players need to undertake these in training to prepare for the worst-case scenario in matches. Half-backs, midfielders and half-forwards may need additional conditioning as they cover greater TD and relative distance compared to full-backs and full-forwards at senior, U21 and U17. All positions can perform similar sprint training, as there were only minimal differences between positions at each level. No matter what the level (elite senior, U21 and U17 and sub-elite), the majority of metrics decreased in the second half compared to the first. Nutritional, tactical positional changes and substitutions strategies could be implemented to help minimise this decrement. The results of this thesis provide essential information about the match-play demands of sub-elite senior, elite senior, U21 and U17 competitions. The knowledge can be used to highlight the gaps between sub-elite and elite senior matches and between elite U17, U21 and senior matches. The findings can be used by coaches to benchmark their own team’s performances against these norms and help in the design of appropriate training programmes to help maximise the players’ match-play performances.
... Although time-motion analysis has been used to quantify the physical demands in team sports [15][16][17][18], GPS has been the most popular method of choice in hurling [1-3, 12, 13, 19]. The game of hurling is physically demanding with highintensity running performances (e.g. ...
... Another method that has been used to provide an insight into the physical demands of team sports is the examination of the ball-in-play (BIP) periods [12,15,16,25,26]. The total game duration is a poor indicator of the actual matchplaying time, as the ball was only in-play for 41% of the overall match time in senior hurling [12], 63% in Rugby League [15], and 44% in International Rugby Union [27]. ...
... Furthermore, no BIP and BOP (number of cycles, duration, and type of BOP stoppage) data are available at U17 and U21 competitions, not even a direct comparison between levels has been performed. Research that quantifies the differences in BIP and BOP of each competition would provide a better understanding of a potential gap between levels and further aid the development of game-specific activities [16]. In addition, conditioning players to undertake the physical demands of competition should include the "worst-case scenario" passages of play [13]. ...
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Purpose The current study aimed to investigate the ball-in-play (BIP) and ball-out-of-play (BOP) differences between U17, U21 and senior hurling matches. Methods Video recordings of matches (n = 36) were coded and analysed for BIP and BOP. Time when the ball was continuously in-play was considered BIP, whereas any stoppages were considered BOP. Results The total and mean BIP cycle duration showed no difference between levels. The number of BIP cycles were higher in senior matches compared to U17 (ES = 1.80: large) and U21 (ES = 1.27: large). U17 matches had a lower frequency of BIP cycles between 16 and 30 s (ES = − 1.75: large) compared to senior. Total BOP duration was longer in senior (45:30 ± 4:13 min) matches compared to U17 (36:31 ± 2:30 min, ES = 2.59: very large) and U21 (36:48 ± 2:53 min, ES = 2.40: very large). Senior matches had a longer BOP duration and greater number of BOP cycles than U17 (ES = 0.17: trivial, ES = 2.20: very large, respectively) and U21 (ES = 0.17: trivial, ES = 0.99: moderate, respectively). U17 matches had a lower frequency of BOP cycles > 60 s (ES = − 1.33: large) compared to senior. Conclusion Although there was a difference in the total match duration, U17 and U21 matches have similar BIP time as seniors, suggesting that U17 and U21 players should be conditioned to withstand the elite senior BIP duration. In training practice, high-intensity short-duration games are suggested for repeating the duration demands of competition.
... The proportion of prescribed volume load completed during mid-competition was significantly less than the remainder of the season (Figure 2). This discrepancy between prescribed and actual load during mid-competition may have been the result of a number of factors, such as lack of motivation, players ability to complete prescribed load (strength testing conducted approximately 9-16 weeks prior), representative commitments (up to 3 representative camps and matches), and accumulative neuromuscular fatigue following extensive congested scheduling because of training and match play (18,39). Moreover, psychosocial factors, such as stress at home or stress at work because of success or difficulty winning matches, may affect players' adherence (14). ...
... These players may have experienced greater external loads in training or during matches and subsequently self-selected lower resistance loads. Furthermore, the mid-competition coincided with representative commitments, where matches have been reported to be played at a higher intensity, and training predominantly focuses on technical and tactical training in preparation for competition (18). Actual training loads were closer to prescribed during the late competition, possibly indicating an increased motivation as the season progressed toward the finals. ...
Article
Redman, KJ, Connick, MJ, Beckman, EM, and Kelly, VG. Monitoring prescribed and actual resistance training loads in professional rugby league. J Strength Cond Res XX(X): 000-000, 2021-Coaches devote a considerable amount of time and effort prescribing and selecting exercises to elicit training adaptations. Adherence to the prescribed resistance training load may vary for a number of reasons. The aim of this study was to quantify the difference between prescribed and actual resistance training loads in a team of professional rugby league players. Training loads were quantified using volume load and training intensity throughout a season. The competition was categorized into preseason, early competition, mid-competition, and late competition. Twenty-seven players participated in this study. Four exercises were monitored: back squat, bench press, bench pull, and clean pull. A Friedman's test was used to assess differences between prescribed and actual training loads throughout different phases of the season, for different exercises, and during different weeks in a training block. There were significantly greater differences in prescribed and actual volume loads during the mid-competition in comparison to all other phases of the season (p , 0.01). Although players adherence to prescribed training intensity was significantly greater during the preseason compared with the remainder of the season (p , 0.05), they completed significantly less prescribed training load during week 1 in comparison to week 4 within a training block (p , 0.05). The results of this study demonstrate that regular monitoring of completed resistance training loads may be of greater importance to strength and conditioning coaches to assist in examining potential progress and fatigue or allow for more accurate prescription of load to enhance adaptation throughout a season.
... These periods have been termed "activity" and "recovery" cycles and provide information about the normative time that the ball is in and out of play, allowing coaches to design training drills that reflect the intermittent profile of the competition (Gabbett, 2012;. Studies in professional rugby league have revealed the occurrence of continuous passages of play that exceed 6 min, which four times greater than the average time that the ball is continuously in play (Gabbett, 2015a). The longest continuous passage of play, often associated with the "worst-case" scenario, has important applications for Australian Football training, though this data is currently unavailable. ...
Article
The current study aimed to describe the distribution of physical and technical performance during the different phases of play in professional Australian Football. The phases of play (offence, defence, contested play, umpire stoppages, set shots and goal resets) were manually coded from video footage for a single team competing in 18 matches in the Australian Football League. Measures of physical performance including total distance (m), average speed (m · min⁻¹), low-speed running (LSR, <14.4 km h⁻¹), high-speed running (HSR, >14.4 km h⁻¹), accelerations (2.78 m · s⁻²) and decelerations (−2.78 m · s⁻²) were derived from each phase of play via global positioning system (GPS) devices. Technical skill data including tackles, handballs and kicks were obtained from a commercial statistics provider and derived from each phase of play. Linear mixed-effects models and effect sizes were used to assess and reflect the differences in physical and technical performance between the six phases of play. Activity and recovery cycles, defined as periods where the ball was in or out of play were also described using mean and 95% confidence intervals. The analysis showed that several similarities existed between offence and defence for physical performance metrics. Contested play involved the highest total distance, LSR, accelerations, decelerations and tackles compared to all other phases. Offence and defence involved the highest average speed and HSR running distances. Handballs and kicks were highest during offence, while tackles were highest during contested play, followed by defence. Activity and recovery cycles involved mean durations of ~110 and ~39 s and average speeds of ~160 and ~84 m · min⁻¹, respectively. The integration of video, GPS and technical skill data can be used to investigate specific phases of Australian Football match-play and subsequently guide match analysis and training design.
... The focus of papers has shifted from investigating variables such as total distance covered to identifying critical performance indicators, in particular the influence of repeated high intensity efforts (Gabbett et al., 2013). Papers have added context to these demands by identifying the differences between winning and losing teams (Gabbett, 2013a), duration of match recovery times (Murray et al., 2014), activity cycles recognising how long the ball is in play (Kempton et al., 2013;Gabbett, 2015) and the demands across different field positions when attacking or defending (Gabbett et al., 2013). The latest papers have looked at the intensity of games across small in game periods (Delaney et al., 2015) as well as the tactical and technical differences that impact on a team's success (Gabbett, 2014;Hulin et al., 2014). ...
Article
There is a paucity of information comparing competitive rugby league match play dynamics between northern and southern hemispheres. Notably, differences in the match demands of games played in an intensive period have not previously been reported. This study is the first to assess such demands, quantified using GPS/accelerometer technology, during a competitive three game period that comprised two games in England, interspersed with one game in Australia. The three games were completed over a period of 23 days. In-game data from fifteen elite level rugby league players were collected. The focus was to assess differences in activity profiles undertaken in each game. There were significant increases in the total number of high speed sprints, distance covered at high speed and acceleration/deceleration efforts undertaken in Australia when compared to England. No significant differences in other key performance indicators were observed. The current findings demonstrate minimal differences in the activity profiles of game play in elite professional rugby league, with the exception of high-speed activity and acceleration/deceleration efforts. The European team were defeated in their game in Australia, with clearly higher levels of total high speed sprints, acceleration and deceleration efforts being observed in that game when compared with games undertaken in England. Such findings emphasise the continuing use of GPS/accelerometer technologies in determining in-game performance characteristics associated with likely success, though the milieu of factors contributing to success must be considered in entirety.
... Furthermore, Top 4 NRL teams have a greater proportion of long activity cycles than Bottom 4 NRL teams [48]. Activity cycles of 'State-of-Origin' competition between the states of Queensland and New South Wales in Australia even exceed those of NRL matches, with a greater proportion of long-duration activity cycles [49]. Collectively, these data highlight the importance of performing prolonged high-intensity exercise ([10 min) and the ability to recover during short rest periods. ...
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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.
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The purpose of this paper is to provide a comprehensive review of the science of rugby league football at all levels of competition (i.e. junior, amateur, semi-professional, professional), with special reference to all discipline-specific scientific research performed in rugby league (i.e. physiological, psychological, injury epidemiology, strength and conditioning, performance analysis). Rugby league football is played at junior and senior levels in several countries worldwide. A rugby league team consists of 13 players (6 forwards and 7 backs). The game is played over two 30 - 40 min halves (depending on the standard of competition) separated by a 10 min rest interval. Several studies have documented the physiological capacities and injury rates of rugby league players. More recently, studies have investigated the physiological demands of competition. Interestingly, the physiological capacities of players, the incidence of injury and the physiological demands of competition all increase as the playing standard is increased. Mean blood lactate concentrations of 5.2, 7.2 and 9.1 mmol . l(-1) have been reported during competition for amateur, semi-professional and professional rugby league players respectively. Mean heart rates of 152 beats . min(-1) (78% of maximal heart rate), 166 beats . min(-1) (84% of maximal heart rate) and 172 beats . min(-1) (93% of maximal heart rate) have been recorded for amateur, semi-professional and junior elite rugby league players respectively. Skill-based conditioning games have been used to develop the skill and fitness of rugby league players, with mean heart rate and blood lactate responses during these activities almost identical to those obtained during competition. In addition, recent studies have shown that most training injuries are sustained in traditional conditioning activities that involve no skill component (i.e. running without the ball), whereas the incidence of injuries while participating in skill-based conditioning games is low. Collaborative research among the various sport science disciplines is required to identify strategies to reduce the incidence of injury and enhance the performance of rugby league players. An understanding of the movement patterns and physiological demands of different positions at all standards of competition would allow the development of strength and conditioning programmes to meet the precise requirements of these positions. Finally, studies investigating the impact of improvements in physiological capacities (including the effect of different strength and conditioning programmes) on rugby league playing performance are warranted.
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Rugby league football is played in several countries worldwide. A rugby league team consists of 13 players (6 forwards and 7 backs), with matches played over two 40-minute halves separated by a 10-minute rest interval. Several studies have documented the physiological capacities of rugby league players and the physiological demands of competition, with the physiological capacities of players and the physiological demands of competition increasing as the playing level is increased. However, there is also evidence to suggest that the physiological capacities of players may deteriorate as the season progresses, with reductions in muscular power and maximal aerobic power and increases in skinfold thickness occurring towards the end of the rugby league season, when training loads are lowest and match loads and injury rates are at their highest. Player fatigue and playing intensity have been suggested to contribute to injuries in rugby league, with a recent study reporting a significant correlation (r = 0.74) between match injury rates and playing intensity in semi-professional rugby league players. Studies have also reported a higher risk of injury in players with low 10-m and 40-m speed, while players with a low maximal aerobic power had a greater risk of sustaining a contact injury. Furthermore, players who completed <18 weeks of training prior to sustaining their initial injury were at greater risk of sustaining a subsequent injury. These findings provide some explanation for the high incidence of fatigue-related injuries in rugby league players and highlight the importance of speed and endurance training to reduce the incidence of injury in rugby league players. To date, most, but not all, studies have investigated the movement patterns and physiological demands of rugby league competition, with little emphasis on how training activities simulate the competition environment. An understanding of the movement patterns and physiological demands of specific individual positions during training and competition would allow the development of strength and conditioning programmes to meet the specific requirements of these positions. In addition, further research is required to provide information on the repeated effort demands of rugby league. A test that assesses repeated effort performance and employs distances, tackles and intensities specific to rugby league, while also simulating work-to-rest ratios similar to rugby league competition, is warranted.
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Statistical guidelines and expert statements are now available to assist in the analysis and reporting of studies in some biomedical disciplines. We present here a more progressive resource for sample-based studies, meta-analyses, and case studies in sports medicine and exercise science. We offer forthright advice on the following controversial or novel issues: using precision of estimation for inferences about population effects in preference to null-hypothesis testing, which is inadequate for assessing clinical or practical importance; justifying sample size via acceptable precision or confidence for clinical decisions rather than via adequate power for statistical significance; showing SD rather than SEM, to better communicate the magnitude of differences in means and nonuniformity of error; avoiding purely nonparametric analyses, which cannot provide inferences about magnitude and are unnecessary; using regression statistics in validity studies, in preference to the impractical and biased limits of agreement; making greater use of qualitative methods to enrich sample-based quantitative projects; and seeking ethics approval for public access to the depersonalized raw data of a study, to address the need for more scrutiny of research and better meta-analyses. Advice on less contentious issues includes the following: using covariates in linear models to adjust for confounders, to account for individual differences, and to identify potential mechanisms of an effect; using log transformation to deal with nonuniformity of effects and error; identifying and deleting outliers; presenting descriptive, effect, and inferential statistics in appropriate formats; and contending with bias arising from problems with sampling, assignment, blinding, measurement error, and researchers' prejudices. This article should advance the field by stimulating debate, promoting innovative approaches, and serving as a useful checklist for authors, reviewers, and editors.
Rugby league injuries at State of Origin level.
  • Orchard
Orchard, J and Hoskins, W. Rugby league injuries at State of Origin level. Sport Health 25: 19-24, 2007.