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Bio-banding in Sport: Applications to Competition, Talent Identification, and Strength and Conditioning of Youth Athletes
Abstract
Bio-banding is the process of grouping athletes on the basis of attributes associated with growth and maturation rather than chronological age. Children of the same age vary considerably in biological maturation with some individuals maturing in advance or delay of their peers. The timing of maturation has important implications for competition, talent identification, and training. Increased awareness and interest in the subject of maturation has sparked a renewed interest in the study and application of biobanding. This overview describes the purpose and process of bio-banding, potential benefits and limitations, and describes some recent advances in its application in youth sports.
... In youth and junior triathlon events, competitive categories are grouped according to chronological age: 8-9, 10-11, 12-13, 14-15, and 16-17 years (World Triathlon, 2020). Although age intervals are small to promote a fairer and more balanced competitive environment, it is important to bear in mind that children of the same chronological age may vary in biological maturity, with some individuals maturing earlier or later than others (Cumming et al., 2017). ...
... Bio-banding has been proposed as an alternative to the chronological grouping of young athletes (Rogol et al., 2018). This method consists of categorizing athletes based on physical and maturational characteristics rather than chronological age, with the aim of reducing competitive inequalities generated by differences in size and maturity (Abbott et al., 2019;Baxter-Jones et al., 2020;Cumming et al., 2017;Malina et al., 2015;Towlson et al., 2024). Application of bio-banding in soccer, for instance, has had positive effects on talent development (Arroyo-Moya, 2023; Barrett et al., 2022;Cumming et al., 2017b;Ludin et al., 2022;Massa et al., 2022), holistic development (Abbott et al., 2019;Bradley et al., 2019;Cumming et al., 2017;Malina et al., 2019), and performance and training load management (Cumming et al., 2017;Gundersen et al., 2022;Ludin et al., 2022;Malina et al., 2019;Meylan et al., 2010). ...
... This method consists of categorizing athletes based on physical and maturational characteristics rather than chronological age, with the aim of reducing competitive inequalities generated by differences in size and maturity (Abbott et al., 2019;Baxter-Jones et al., 2020;Cumming et al., 2017;Malina et al., 2015;Towlson et al., 2024). Application of bio-banding in soccer, for instance, has had positive effects on talent development (Arroyo-Moya, 2023; Barrett et al., 2022;Cumming et al., 2017b;Ludin et al., 2022;Massa et al., 2022), holistic development (Abbott et al., 2019;Bradley et al., 2019;Cumming et al., 2017;Malina et al., 2019), and performance and training load management (Cumming et al., 2017;Gundersen et al., 2022;Ludin et al., 2022;Malina et al., 2019;Meylan et al., 2010). Different methods can be used to categorize young individuals according to biological age or maturity status. ...
Introduction: The maturation process in young athletes has been widely studied due to its influence on sports performance and training responses. In endurance sports such as triathlon, understanding biological development is crucial for guiding athlete development and competition structuring. Objective: The aim of this study was to investigate the correlation between biological age and chronological age, assess variations in maturity status within age groups, and determine whether bio-banding should be recommended for youth and junior triathlon. Methodology: A cross-sectional study was conducted with 296 young triathletes of both sexes who participated in national, state, or regional multi-sport events in Brazil between 2022 and 2023. Biological maturity status was estimated using the percentage of predicted adult height (%PAH) and predicted age at peak height velocity (APHV). Results: A strong correlation was observed between chronological age and biological age, suggesting that most young triathletes developed within expected standards. Both indicators were considered good estimators of maturity, although the predicted age at peak height velocity appeared to better reflect intra-group variation. The results are consistent with previous studies that support the use of non-invasive maturity indicators in youth sports. The application of these indicators contributes to a more equitable interpretation of performance and training potential across maturity stages. Conclusions: It is concluded that age grouping remains an appropriate method for organizing youth triathlon competitions. However, bio-banding emerges as a strategic alternative for planning training and guiding talent identification, considering biological maturity and its influence on performance.
... Similarly, Santos et al. (2023) explored how altering the number of creative opponents influences youth players' creative and tactical performance. A promising niche in the literature introduced bio-banding, where players are grouped by maturity status rather than chronological age (Cumming et al., 2017;Towlson et al., 2022). These procedures have promoted more appropriate developmental environments and facilitated training periodization (Cumming et al., 2017;Lüdin et al., 2022;Praça et al., 2017;Santos et al., 2023). ...
... A promising niche in the literature introduced bio-banding, where players are grouped by maturity status rather than chronological age (Cumming et al., 2017;Towlson et al., 2022). These procedures have promoted more appropriate developmental environments and facilitated training periodization (Cumming et al., 2017;Lüdin et al., 2022;Praça et al., 2017;Santos et al., 2023). Additionally, these approaches have positively influenced participants' perceptions, with players reporting that such strategies presented unique challenges and learning experiences (Cumming et al., 2018). ...
... The lower success rates in passes, shots, and dribbles during condition I ACTvsACT affirm higher competitive balance, necessitating quicker decisions, faster play, and sustained high-intensity efforts . Conversely, the superior distance covered at walking and higher success rates in technical-tactical actions during condition II ACTvsSED suggest matches that are less physically and technically challenging (Cumming et al., 2017;Lüdin et al., 2022). For instance, increased successful dribbles may lead to additional shots and passes, as dribbling past opponents provides ACT players with more time and space to scan the environment and identify unmarked teammate or goal-scoring opportunities (Coutinho et al., 2020). ...
... Traditionally, talent identification programs have included morphological, physical and mostly performance parameters (11,34). However, most of these programs have aimed at young athletes during their pubertal years, not taking into consideration the potential development of these attributes based on biological maturity (35). In addition, only a few recent studies have examined athletes with similar chronological age that belong to different maturity groups (36,37). ...
... The talent identification process in individual sports have been traditionally focused on physical, morphological and performance characteristics of the athletes at a particular moment in time (34). Consequently, early maturers within the same age group have benefited from their more advanced capacities increasing their possibilities of sport success or team selection with respect to late maturers (34, 35). If maturity status is not taken into consideration for talent identification purposes at young ages, there is a risk of excluding potentially talented athletes with a delayed biological age (11,35). ...
... Consequently, early maturers within the same age group have benefited from their more advanced capacities increasing their possibilities of sport success or team selection with respect to late maturers (34, 35). If maturity status is not taken into consideration for talent identification purposes at young ages, there is a risk of excluding potentially talented athletes with a delayed biological age (11,35). The results of the current investigation provide a necessary first step towards understanding the influence of menarche as a maturational determinant in the timing of the development of morphological, physical and performance capacities in young competitive female swimmers. ...
Purpose
At the age of menarche, there is a significant increase in the secretion of sex hormones, affecting physical and morphological growth. This study aimed to investigate the impact of menarche on the development of body dimensions, fitness level, technical skills and performance in pubertal female swimmers over one year of training.
Methods
Nineteen young swimmers within the same age group (11–12 years) were assessed in two consecutive years. Participants were allocated into two groups (Menarche and Pre-menarche) based on the presence of menarche in the transition from the 1 st to the 2 nd year. Anthropometric measures, physical fitness (countermovement jump and handgrip), skill tests (glide and 10 m underwater from start and push) and specific performance tests (50, 100, and 200 m) were evaluated.
Results
Menarche-based differences were identified in handgrip strength, 10 m underwater from push, and sprint performance in the 2 nd year ( P < 0.05), with menarcheal girls showing greater improvement in these attributes throughout the year. In contrast, premenarcheal swimmers exhibited greater increases in body dimensions (stature, body mass, foot and hand lengths) up to 9.5% and improved performance in the 200 m, reducing the significant differences compared to menarcheal girls in the 2 nd year. Muscular strength, hand length, and 10 m underwater performance were significantly associated with short-distance performance, especially in menarcheal girls ( r > 0.59), while maturity and training were more related to 200 m performance ( P < 0.05).
Conclusions
These findings highlight the different timing of improvement in female swimmers’ attributes based on menarche. Along with the age at peak height velocity (APHV), the age of menarche might be a valuable tool for monitoring and adapting training and talent identification processes.
... This creates a challenge for coaches and practitioners working in youth sports, particularly when the aim is to identify and select talented individuals with the potential to become elite athletes. Earlier maturing athletes are afforded significant advantages in size, strength, speed, and power, allowing them to physically outperform their later maturing peers [13]. For the purpose of identifying and nurturing talented young athletes, having a clearer understanding of how sprinting speed and jump performance differ between maturity groups (pre-, circa-, post-PHV) will improve practitioners' ability to evaluate the performance of individual athletes in accordance with their maturity status at a given point in time, providing an alternative perspective to age-based evaluations where maturity is not considered. ...
... Study characteristics were manually extracted into a Microsoft Office Excel spreadsheet (version 2203) by all authors (JB [13], TJ [6], PGS [6], PR [5], MC [6]). The data set included information on the lead author, year of publication, sample size, population, sex, maturity assessment method used, equipment used and set-up. ...
... Coaches and practitioners involved in the identification, selection/deselection of male youth athletes are advised to consider the magnitude of differences in sprinting and jumping performance shown in this review and consider how this may influence performance in the context of their sport. Bio-banding [13] is a process that has been successfully utilized in team sports [69,70] that could be considered as an alternative learning environment and/or competition experience, if stakeholders wish to reduce any maturity status-related advantages or disadvantages based on the differences shown in sprinting speed and jumping performance in the current review. ...
Background
Large interindividual differences can exist in the timing and tempo of growth and maturation of youth athletes. This can provide significant physical performance advantages to young athletes who mature in advance of their peers.
Objective
The aim of this systematic review was to determine the magnitude of differences in sprinting and jumping performance in youth of different maturity status (classified as pre-, circa- or post-peak height velocity [PHV]) (aged < 18 years) to enhance the evaluation of performance.
Methods
Eligibility criteria for inclusion were as follows: (1) the study had cross-sectional data available; (2) participants were male and/or female ≤ 18 years of age; (3) a somatic measure of maturity was used to identify maturity status (e.g. Mirwald or Khamis-Roche methods) with at least two maturity status classifications present; (4) the study included a measurement of sprinting speed (e.g. 10–100-m sprint data) and/or jump tests commonly used to assess power (e.g. countermovement jump [CMJ]). Searches were conducted up to November 2024 in PubMed, Embase, SPORTDiscus and preprint servers SportRxiv and medRxiv to identify any unpublished trials. Risk of bias and study quality was assessed using the Appraisal tool for Cross‐Sectional Studies (AXIS). Meta-analysis was computed using a random-effects model.
Results
The search identified 1578 studies. From those, 40 studies were identified for qualitative assessment and quantitative synthesis. In the primary analysis, 21 studies provided data for measures of speed, and 19 studies provided data for measures of power using jump tests. Sprinting and jumping performance increased with advancing maturity status and overall effect sizes were predominantly moderate to large between maturity groups. Pre-PHV versus post-PHV comparisons found moderate to large overall effect sizes (ES) for sprinting performance (10-m ES 1.34 [95% CI 0.87–1.80]; 20-m ES 1.40 [95% CI 0.85–1.96]; and 30-m ES 0.93 [95% CI 0.15–1.76] sprint times) and large to very large ES for the jump tests (CMJ ES 1.53 [95% CI 1.14–1.92]; squat jump ES 1.32 [95% CI 0.70–1.94]; and standing long jump ES 2.18 [95% CI 1.32–3.04]). When comparing consecutive maturity groups (i.e. pre- to circa-PHV and circa- to post-PHV), ES were predominantly moderate across the sprinting and jumping measures, with only a trivial difference found in 30-m sprint time (ES 0.45 [95% CI 0.21–0.69]) for the circa- to post-PHV comparisons.
Conclusion
Large differences exist in sprinting and jumping performance between the least and most mature male athletes (pre- and post-PHV), with trivial to moderate ES indicated between consecutive groups (e.g. pre- and circa-PHV). Practitioners working with youth athletes should consider how these differences may impact performance in the athlete’s sport, and regularly assess individual maturity to accurately evaluate performance against age and maturity group benchmarks to account for large differences in maturity that exist within chronological age groups. It should be noted we observed inconsistencies in maturity thresholds and test methods; thus, standardization is required for future research.
... Such approaches have gained importance for its contribution to improved outcomes (Ramalho & Petrica, 2023). Implementation of EBP not only relies on the organization's financial resources but also on its commitment to sport science and a culture that supports EBP adoption (Cumming, 2018;Cumming, Lloyd, Oliver, Eisenmann, & Malina, 2017;Fullagar et al., 2019b;Houtmeyers et al., 2021). In the context of youth football development there is growing evidence of the benefits of incorporating and acknowledging biological maturation, offering potential advantages in terms of talent identification, injury prevention, and the long-term development of homegrown players (Hall et al., 2022;Hill, John, McGee, & Cumming, 2023;Lüdin, Donath, Cobley, & Romann, 2021;Monasterio et al., 2024;Monasterio et al., 2021a;Towlson, Cobley, Parkin, & Lovell, 2018) . ...
... In the context of youth football development there is growing evidence of the benefits of incorporating and acknowledging biological maturation, offering potential advantages in terms of talent identification, injury prevention, and the long-term development of homegrown players (Hall et al., 2022;Hill, John, McGee, & Cumming, 2023;Lüdin, Donath, Cobley, & Romann, 2021;Monasterio et al., 2024;Monasterio et al., 2021a;Towlson, Cobley, Parkin, & Lovell, 2018) . Biological maturation can be defined in terms of status, tempo, and timing (Cumming et al., 2017). Several approaches are available to evaluate these aspects, each presenting distinct strength and limitations. ...
... Alternatively, noninvasive assessments of maturity status and timing, derived from anthropometric data are becoming increasingly popular (Arenas, Frenger, Skorski, & Meyer, 2023;Salter, De Ste Croix, Hughes, Weston, & Towlson, 2021). These approaches can be integrated into standard growth monitoring practices, thus, enabling grouping and assessment of players based on their biological maturation status rather than their chronological age, a process currently known as "biobanding" (Cumming, 2018;Cumming et al., 2017). This strategic reorganization aims to minimize significant withingroup variances in athlete performance resulting from variations in maturation timing within age-groups (Towlson et al., 2018). ...
Purpose
This study examined the extent to which German male football academies adopt evidence-based practices (EBP) and their impact on the execution of biological maturation assessments. It also explored perceived barriers to implementing these assessments.
Methods
With a 71.4% completion rate, 40 support staff members from German male football academies completed an online survey. The survey included questions on clubs’ beliefs about EBP, maturation assessment and monitoring practices, and data utilization. Responses were structured as multiple-choice or unipolar Likert scale questions with four to five labeled points. A magnitude-based decision approach was used to interpret findings.
Results
Results indicate a strong integration of EBP within German football academies, reflected in an EBP index of 3.66 ± 0.89 on a 5-point Likert scale. Significant differences ( p = 0.035) were observed between participants conducting biological maturation assessments (3.91 ± 0.65) and those who do not (3.44 ± 0.71). Time constraints (68%) and staffing limitations were identified as primary barriers.
Conclusion
The findings emphasize the positive adoption of evidence-based practices in German football academies, with higher EBP index scores linked to conducting biological maturation assessments. The higher EBP index scores among those conducting biological maturation assessments highlight the crucial role of organizational culture in implementation. Structural barriers, contributing to the perceived “time constraints”, are key challenges, while staff competence is not a limiting factor. Promoting innovative, solution-oriented practices could help address these barriers, enhance decision-making, and better align processes with long-term player development goals.
... 24 Additionally, differences in tactical understanding, team playing styles/formations, and variations in coaching philosophies contribute to variability in performance metrics. 24,25 However, this complexity can be even more pronounced for younger age groups due to the influence of developmental stages and player maturity, 26,27 which may result in greater variability in performance during matches. Thus, investigating match performance variability between progressive age categories could provide some insights into the developmental needs of players and their preparation for progression to higher competitive levels. ...
... 37 This study found greater variability in HIR and SPR distances among the U17WC teams, suggesting that youth players may experience more fluctuation in their physical outputs, possibly due to differences in maturity status, tactical approaches, or coaching strategies. 25,26 Due to the higher variability in physical outputs, managing players becomes more complex, thus highlighting the need for tailored training programs that address the unique physical demands at each developmental stage. Previous research has highlighted the challenges national team staff face in this regard due to the limited time they have with players compared with club staff. ...
... These plans should address differences in physical maturity and tactical understanding, such as providing extra support in tactical positioning and game awareness for players who may be less physically developed. 26 For players transitioning from U20 to senior levels, more emphasis should be placed on replicating the technical/tactical complexity observed in senior match-play, including drills that simulate the advanced tactical patterns and fluid play seen in the MWC. Effective communication and collaboration between national and club team staff is vital to achieving these detail goals. ...
Purpose:
This study aimed to investigate differences in match physical and technical/tactical performance of teams across different competitive levels in international soccer: FIFA Men's World Cup Qatar 2022 (MWC), FIFA U20 World Cup Argentina 2023 (U20WC), and FIFA U17 World Cup Indonesia 2023 (U17WC).
Methods:
From a total of 168 games, 138 games were analyzed (N = 276 game observations) using an optical tracking system.
Results:
On average, the U17WC teams exhibited reduced total running (3% less), high-intensity running (14%-16% less), and sprinting (18%-26% less) distance than the MWC and U20WC teams (P ≤ .0023; effect size [ES]: 0.8-1.5). The MWC teams displayed 4% to 5% higher accuracy in passing and executing line breaks (P ≤ .0188; ES: 0.6-0.7), along with increased offers to receive the ball (53%-118% more) and movements to receive the ball (44%-101% more), and received the ball (61%-137%) more often than the U20WC and U17WC teams (P < .001; ES: 1.1-2.1). Moreover, notable decreases in defensive pressure (-18% to -32%) and forced turnovers (-26% to -32%) were observed in the U17WC than other competitions (P ≤ .0001; ES: 0.8-2.2). Greater variability was observed among the U17WC teams in several metrics, including high-intensity/sprinting distances, attempts at goal, and receptions in the final third.
Conclusions:
These findings demonstrate that as the competitive level increases, so do the physical demands, advanced technical skills, and tactical fluidity/adaptability. However, caution should be exercised when interpreting match performance of younger age groups, as higher variability was evident in both physical and technical/tactical performance in matches.
... This is an issue in talent identification as biases in selection affect which players gain access to the talent development pathway and obscure talented athletes behind physical advantages [26,38]. Taller athletes at ~ 12 years old are typically early maturing [39,40] and early maturing athletes exhibit greater physical fitness compared to later maturing athletes during early adolescence [39,40]. However, there are no differences in physical performance between these groups once they reach adulthood [41]. ...
... This is an issue in talent identification as biases in selection affect which players gain access to the talent development pathway and obscure talented athletes behind physical advantages [26,38]. Taller athletes at ~ 12 years old are typically early maturing [39,40] and early maturing athletes exhibit greater physical fitness compared to later maturing athletes during early adolescence [39,40]. However, there are no differences in physical performance between these groups once they reach adulthood [41]. ...
... However, there are no differences in physical performance between these groups once they reach adulthood [41]. Athletes excluded due to maturation selection bias have limited exposure to high quality coaching and can be systemically excluded from the talent pathway [39,40]. Another selection bias is the relative age effect [16,26,27], however there was no evidence of this bias in this study. ...
Talent identification focuses on the ability to identify and select young athletes who show potential for future sporting success. The aim of this study was to compare the anthropometry and physical performance of male youth Australian Football players selected and not selected into a high performance sports academy program. Its secondary aim was to determine whether selection into a talent development environment at 12 years old affects the odds of selection into subsequent junior national level representative and senior professional Australian Football programs. 168 youth males (11.7 ± 0.4 years) who nominated for the selection process to attend a specialised high school sports academy completed a series of physical and anthropometric assessments. The data collection period occurred over seven years (2013–2019), with a prognostic period between one to ten years. Results found selected 12 years olds were taller and had greater lower body power, speed and aerobic fitness than non-selected athletes. A combination of height, aerobic fitness, and lower body power best distinguished between selected and non-selected players. This discriminant analysis had high accuracy and greater sensitivity than specificity. Further, athletes selected into the talent development environment had a much greater likelihood of being selected into junior state/national (54-fold) and senior professional (5-fold) teams than non-selected athletes. Overall, the findings demonstrate some support for the prognostic ability of selection into a talent development program at 12 years old to predict later selection in the talent pathway. These findings support the role of talent development programs in the development of male Australian footballers.
... Owing to practical issues surrounding longitudinal anthropometric data collection (i.e., athletes transitioning between teams and sports), methods of estimating maturity status from cross-sectional anthropometric data are commonly used in talent development pathways. Estimates of eventual adult height and the percentage of predicted adult height (%PAH) are recognized as primary methods of estimating maturity status (15,56), providing a more accurate estimate of maturity status when compared with maturity offset predictions (63). The %PAH method by Khamis and Roche (41) has an average error of approximately 2 cm when predicting eventual adult height. ...
... This method uses the individual's current body mass and height, in addition to midparental height, to predict final adult height [Equation 1] (41). The % PAH provides a useful measure for estimating somatic maturity, whereby the current height of a child is expressed as a percentage of their predicted adult height, thereby indicating the athlete's maturity status at the time of observation (15). Figure 1 shows the steps required to determine an individual's %PAH. ...
... It has also been suggested that a bioband of ,85% PAH denotes the prepubertal period, 85-90% PAH reflects the early pubertal period, 90-95% represents the midpubertal period, and .95% PAH identifies the late pubertal period (15). To estimate the timing of maturation, %PAH can also be calibrated with age-specific and sexspecific reference standards (e.g., reference standards obtained from the UK 1990 growth reference data (23) functions used within the excel files) thereby allowing measurements for estimates of maturity status to be conducted regularly (i.e., approximately every 3 months) (55). ...
Growth and maturation have a significant influence on naturally occurring changes in performance, training-induced adaptations, injury risk, and psychosocial development and should, therefore, be important considerations within talent identification and development pathways for young weightlifters. Key stakeholders in youth weightlifting require an understanding of growth and maturation to support the long-term development of athletes and ensure that future potential is considered rather than making judgments based on enhanced physical qualities synonymous with advanced stages of maturation. This article considers methods of assessing biological maturation and growth rates and then explores how weightlifting performance can be influenced by growth and maturation. The article is accompanied by an Excel template to estimate maturity status and timing. Finally, recommendations are offered to help practitioners embed growth and maturation analysis within youth weightlifting pathways to enhance performance, reduce injury risk, and create optimal training and competition environments.
... Analyses were done with SPSS version 20.0 (SPSS Inc, IBM Company, N.Y., USA). The longitudinal height records for 58 of the 87 U13 players with four or five observations general [6] and specifically with soccer players [7] are interested in monitoring growth rates of individual players in an effort to prescribe developmentally appropriate training loads and content, to avoid or perhaps better assess risk for injury, and to evaluate athletic aptitude and potential relative to the adolescent growth spurt, specifically the initiation of the spurt (take-off) and the interval of maximum rate of growth in height (PHV). ...
... Given the increased interest in monitoring the estimated rates of growth in individual athletes [6,7], the purpose of this study is twofold. It initially considers estimated annual increments (rates of growth) in height and weight based on annual observations spanning the interval of adolescence in a mixed-longitudinal sample of male soccer players, and then compares the estimated increments with reference values for the general population and also with estimated increments in height and weight derived from a recent review of the growth status of youth soccer players. ...
... In contrast to body size per se (Figures 1 and 3 of registered academy players 9 years and older at three-to-four month intervals [7]. The growth status and estimated rates of individual players, in parallel with fitness measurements and injury audits, are monitored in an effort to better understand the impact of the transition into the adolescent growth spurt on fitness and performance and on the incidence and burden of injury. ...
Annual increments in height and weight were estimated in a mixed-longitudinal sample of Portuguese male soccer players 11–14 years at baseline. This study aims to compare estimated increments with reference values for the general population and also with estimates from youth soccer literature. The sample included 87 under-13 (U13) and 72 under-15 (U15) players. Allowing for drop-outs and/or transfers, participants were followed over five seasons. Annual measurements of height and weight were taken for the total mixedlongitudinal sample of 571 players, from which annual increments were calculated for 409 occasions. Mean heights and weights of the sample and median annual increments were compared with corresponding estimates for the general population in addition to soccer players based on studies spanning 2000–2015. Mean heights of the sample were slightly but consistently less than the reference, while mean weights were below the reference at 11–13 years and approximated the reference at 14–18 years. Median annual height and weight increments of the soccer players approximated the respective medians for the general population, but increments among individual players varied considerably with age. In contrast, the heights and weights of the Portuguese players were below the means for the composite sample of soccer players except at 18 years, but estimated increments were similar to the composite sample. In summary, increments in the heights and weights of the Portuguese players approximated the general population and means for other soccer players, while mean heights were consistently less than the reference except at 18 years.
... The heights of each player's biological parents were self-reported and adjusted for overestimation using the equations by Epstein et al. [17]. Therefore, athletes were classified according to maturity status using percentage of PAH: circa-PHV represents 88%-96% of PAH, pre-PHV represents <88% of PAH, and post-PHV represents >96% of PAH [18][19][20]. The use of the Khamis-Roche method [16], instead of other methods such as the Tanner-Whitehouse method, is justified by the fact that it does not require skeletal X-rays, making it safer, quicker, and easier to apply in field settings such as youth football academies. ...
... Maturation stages refer to the physical, hormonal, and biological development processes during puberty, occurring at different times in athletes, regardless of their chronological age. Most studies classify athletes as pre-PHV (up to 88% of estimated height), circa-PHV (between 88% and 96%), and post-PHV (above 96%) [1,18,24]. Mandorino et al. concluded that athletes in the circa-PHV and post-PHV stages experience higher injury rates and impacts compared to pre-PHV athletes, while also demonstrating a lower recovery capacity [4,6]. Pre-PHV athletes have an injury risk approximately three times lower than that of a circa-PHV athlete [23]. ...
Currently, many children and teenagers dream of becoming football players and dedicate a large part of their time to achieving this goal. The clubs’ medical and performance departments' primary mission is to reduce the risk of injury to these athletes, allowing them to have more playing and training time to develop their full capabilities. This study aimed to investigate whether participation in youth football tournaments with congested schedules increases the risk of injury in U15 footballers, particularly during critical stages of maturation. In this way, in a retrospective manner, an analysis was conducted of the injuries recorded after a period marked by the participation of a U15 elite team in a preseason youth football tournament. Additionally, the maturational stage of each athlete on this team was recorded and the external workload data through the Global Positioning System (GPS), which included total distance (TD), high-speed running (HSR), accelerations and decelerations greater than or less than 2 m·s⁻² (ACC-DEC2), and accelerations and decelerations greater than or less than 3 m·s⁻² (ACC-DEC3), from the weeks before the tournament were used, aiming to understand whether, in the injured athletes, the accumulation of these metrics during the tournament exceeded the accumulation of the same metrics before the tournament. According to the results obtained, eight athletes sustained injuries during the tournament and the two weeks following it. All injured athletes were in the circa or post-peak height velocity (PHV) maturation stage. In the analysis of the GPS data, it was found that 87.5%, 75%, and 50% of the athletes who suffered an injury exhibited higher rolling sum (RS) values during the tournament compared to their previously recorded maximum values regarding TD, HSR, and ACC-DEC2, respectively. In contrast, 75% of the athletes who did not suffer an injury recorded higher maximum RS values before the tournament compared to during the tournament regarding the parameter of ACC-DEC3. The participation of young footballers in the circa-PHV and post-PHV stages of maturation in several games on consecutive days seems to induce negative consequences for the athletes, namely a greater risk of overuse and acute injuries. The external load metrics presented appear to correlate with the risk of injury, specifically a higher risk of injury in athletes whose accumulated values of TD, HSR, and ACC-DEC2 during competition participation are higher than those previously recorded. Conversely, the presence of higher accumulated values of ACC-DEC3 prior to competition participation compared to those recorded during the competition may be a protective factor regarding injury risk. Careful management of microcycles and applied workloads is a key task to control or prevent injuries and, in this way, increase the young footballers’ participation in games and training.
... El Bio-Banding persigue la máxima equidad competitiva, además de intentar disipar las diferencias motivacionales que se ven en deportes, ya que a los niños/as con una maduración temprana es más probable que sean seleccionados para deportes en los que un mayor tamaño, una mayor fuerza y potencia se relacionen con el éxito, por ejemplo, hockey, fútbol americano, fútbol, rugby, baloncesto y natación (Abbott, et al., 2019;Cumming, et al., 2017). Malina, et al., (2019) señala que la aplicación del Bio-Banding presenta beneficios para: a) jugadores/as con maduración temprana, pueden desarrollar habilidades técnico-tácticas y aplicarlas con mayor velocidad debido a que se mantienen las altas exigencias físicas; y b) jugadores/as con una maduración tardía, que al no verse superados físicamente por los demás jugadores/as pueden demostrar sus habilidades, además de ejercer el rol de líder dentro del equipo. ...
... En muchas ocasiones su puesta en práctica es compleja organizativamente, por la propia estructura deportiva y competitiva de los diferentes órganos responsables de las competiciones. Por lo tanto, si no es posible realizar modificaciones en el diseño de las competiciones, se deberían plantear alternativas para lograr dicha equidad (Cumming et al., 2017;Malina, et al., 2019). En este sentido deberán ser los entrenadores y entrenadoras en primer lugar, así como los propios deportistas en segundo lugar, los que planteen y lleven a cabo propuestas y actuaciones concretas que se puedan llevar a cabo durante la propia práctica deportiva que fomente dicha equidad. ...
The aim of this study was to record the opinion of young basketball players about the importance of equity during the competition, as well as their opinion on the implementation of specifical pedagogical actions during the game to reach it. For this purpose, a questionnaire was administered to 161 basketball players under-12, who are federated in the “Federación de Baloncesto de la Región de Murcia (FBRM)”. This questionnaire is divided into four dimensions and deals with situations in games with large score differences and the feelings that are generated during these games. The most significant results of this study demonstrate that: a) Players prefers situations of equality for matches; b) Players have more fun during matches with the result being tied; c) players do not want to carry out specific pedagogical actions to promote equity when they are winning by a lot, however, when players are far inferior to the other team, they do prefer the other team to carry out specific pedagogical actions to promote equity; d) Players presents feelings related to boredom or apathy in games with a large difference in level between the two teams.
... These findings highlight the variability in precision across different US methods and suggest that the precision of conventional US in our study is lower than previous studies using a similar technology. Additionally, in the context of bio-banding, which groups athletes based on their BA rather than CA, this age range of 3.20 years would lead to inappropriate grouping and negate the purpose of creating an equal playing field (Towlson et al. 2018;Malina et al. 2019;Cumming et al. 2017). Similarly, player-labelling, which categorises athletes based on their BA (Lüdin et al. 2022a), could result in significant misjudgements if based on US-determined BA. ...
... Similarly, player-labelling, which categorises athletes based on their BA (Lüdin et al. 2022a), could result in significant misjudgements if based on US-determined BA. Overor underestimating their BA, and thus their potential, by up to 3.20 years, could lead to players being miscategorised, resulting in misguided trainings, missed opportunities and unfair comparison among peers (Cumming et al. 2017;Lüdin et al. 2022b). ...
The aim of the study was to evaluate conventional ultrasound (US) as a radiation‐free alternative to X‐ray for determining biological age (BA; indicated by skeletal age). BA, was determined in 24 healthy, male, elite youth soccer goalkeepers around peak height velocity (11–16 years of age) using both X‐ray and conventional US scans of the left hand. X‐ray scans were evaluated using the Tanner–Whitehouse 2 method. Conventional US scans served to determine BA via ossification ratios of 13 hand and wrist bones. The new conventional US method showed very strong correlation with X‐ray r = 0.90 (p < 0.05). However, the agreement for the difference in BA and CA, which accounts for age‐related variance, was classified poor (ICC = 0.48, p < 0.05). Additionally, linear regression analysis and the Bland–Altman plot suggested the presence of a systematic and proportional overestimation of BA in younger players and an underestimation of BA in older players. Furthermore, Cohen's kappa showed a moderate agreement between players' classification into maturity groups for the two assessment methods. In conclusion, our study has shown that using US‐derived ossification ratios did not deliver valid results compared to X‐ray when determining BA in youth soccer goalkeepers.
... In contrast, the BG group, where games were matched based on birthdate quartiles, likely provided more equitable competition and developmental opportunities within each quartile. This environment may have minimized the influence of maturity-related advantages, ensuring that aerobic capacity improvements were distributed more evenly across all quartiles (Cumming et al., 2017). Coaches may eventually use small-sided games that emphasize aerobic power, while grouping players by birthdate quartile and technical proficiency to adjust training stimuli. ...
Identifying strategies to mitigate the impact of the Relative Age Effect (RAE) on the development of youth basketball players is crucial. This study aimed to compare two methods of player grouping during competitive small-sided games and match scenarios in training sessions, focusing on their impact on physical performance and technical skill development: mixed birthdate quartiles (CON) versus structured grouping based on birthdate quartiles (BG) over a 6-month period. A randomized controlled trial was conducted with forty-one youth basketball players (age: 12.9 ± 0.7 years) at a trained/developmental level. Throughout the study, participants in the BG group (n = 20) were assigned to small-sided games or match competition scenarios based on their birthdate quartiles, while those in the CON group (n = 21) were grouped with players from mixed quartiles. Players were evaluated at baseline and after the 6-month period for physical performance using countermovement jump (CMJ), change-of-direction (COD), and aerobic capacity (YYIRT). Additionally, they were assessed for technical skills in shooting, passing, and dribbling tests. Comparisons were made based on both birthdate quartiles (quartiles q1-2 relatively older, and q3-4 relatively younger players) and group. After 6 months, the CONq3q4 covered a shorter YYIRT distance than the CONq1q2 group (p = 0.040), achieved a lower CMJ height than both the CONq1q2 (p = 0.024) and BGq1q2 groups (p = 0.019), and had a greater COD deficit than the CONq1q2 group (p = 0.046). Additionally, the CONq3q4 group had longer dribbling times than the CONq1q2 (p = 0.002), BGq1q2 (p = 0.004), and BGq3q4 (p = 0.009) groups. In skill assessments, the CONq3q4 group scored lower in passing than both the CONq1q2 (p = 0.015) and BGq1q2 groups (p = 0.025), and scored lower in shooting compared to the CONq1q2 (p = 0.019), BGq1q2 (p = 0.003), and BGq3q4 (p = 0.003) groups. Grouping youth basketball players based on birthdate quartiles during training can mitigate the relative age effect, promoting more equitable physical and technical development by reducing age-related biases. However, these conclusions are limited by the study's duration and require further research over the long term.
... However, acknowledging error is crucial for the Khamis-Roche method 22 . Median error is slightly over 2 cm in boys and under 2 cm in girls (4.0-7.5 years) 7,23 . Accurate data collection reduces error to ~ 2.0 cm at the 50th percentile but can increase to ~ 0.3 cm at the 90th percentile for 11-to 15-year-olds 1,24 . ...
This study focus is to develop a new model to estimate skeletal age (SA) as a function of the state of biological maturation in male soccer players, and to propose cut-off points to classify the state of biological maturation based on the percentage of adult height (PAH). SA was determined in 747 Portuguese male soccer players, using the Tanner-Whitehouse (TW) 3 method, and PAH was predicted by TW3 (P-TW3) and Khamis-Roche (P-KR) methods. Subsequently, the sensitivity and specificity of the P-TW3 were estimated to classify late, on-time and early maturers to obtain cut-off points, by age; and to develop specific equations for each maturation stage. Both the model using P-TW3 and the model using P-KR showed a SA predictive capacity of 93%. The average differences were similar to zero. P-TW3 cutoff points were established by ROC curve analysis to identify late and early maturers according to their SA. Following, predictive models were developed to estimate SA according to maturity status. The predictive capacity of the models was 87.3% in late maturers, 92.3% in on-time maturers and 93.5% in early maturers. The prediction models are a reliable and cost-effective method to estimate SA in male soccer players.
... This approach ensures a fairer environment for less mature players within the same chronological age group, who might otherwise be disadvantaged by their early-maturing peers' superior strength, power, and speed [18]. Fairer evaluation methods could allow late-maturing players greater opportunities to secure key roles or positions, reducing the likelihood of exclusion due to differences in physical development [32]. ...
Background: Maturation is a complex biological process affecting all tissues, organs, and systems, particularly during adolescence. The Peak Height Velocity (PHV) period, a hallmark of adolescent growth spurts, is associated with individual differentiations in the development of performance attributes amongst youth. Understanding the influence of sports participation on strength and power during the PHV period is essential for optimizing training outcomes and reducing injury risk. This scoping review synthesizes the literature on the strength and power development in athletes during the PHV period across various sports, highlighting the interaction between maturation, training, and performance outcomes. Methods: A systematic search of PubMed and Scopus, supplemented by manual searches, identified peer-reviewed studies from 2004 to 2025. The included longitudinal studies involved structured training and assessed strength-related performance during and around the PHV period. PRISMA-ScR guidelines were followed. Results: Twelve studies met the inclusion criteria. It is found that strength and power are significantly affected during the PHV period and participation in sports mitigates these effects. Training characteristics such as training frequency/volume and sport specificity were key factors. Early maturers often outperformed late maturers, though adolescent awkwardness temporarily reduced performance around PHV. Conclusions: Systematic participation in sports training can limit the phenomenon of adolescent awkwardness in the performance of strength and power. Hence, training programs should be tailored to maturity status, emphasizing skill development, strength training, and injury prevention. Future research should explore individualized training and the mechanisms underlying performance variability during the PHV period.
... Another fundamental aspect is somatic maturation which has demonstrated its association with aerobic performance in young athletes [9], in order to mitigate the impact of maturation on performance the degree of maturation should be monitored [10], since decreases or increases in performance may occur according to the degree of maturation, therefore, the intervention plan should be adjusted taking into account this aspect. Therefore, using VO2max assessment strategies according to bio-banding, considering interindividual differences in the state of maturity among young people of the same chronological age [11], the evaluation of physical fitness will be more objectively assessed. ...
Objectives: VO2max values can be obtained through direct measurement with the use of laboratory tests or can be estimated indirectly by applying field tests, evaluative cut-off points are also required, which are adjusted to the individual characteristics of the subjects, including the sport discipline practiced. The aim of the present work is to categorize aerobic power in male and female athletes according to specific chronological age ranges and Bio-Bands of somatic maturation in young athletes. Methods: A quantitative, cross-sectional, descriptive study was carried out. A total of 613 athletes between 11 and 20 years of age were evaluated. The maximum oxygen consumption was estimated through the 20 m shuttle run test, and the anthropometric variables through the ISAK protocol. The peak heigth velocity was used to establish the somatic maturation bio-bands. For the determination of the aerobic power profile, cut-off points were made with the mean and standard deviation, processed using SPSS 28.0. Results: it is observed that the male group presents higher values than the female group, while the athletics subjects of both sexes present higher values for VO2 max in all age groups and by degree of maturity, with an average of 60 ml.kg.min for males and 51 ml.kg.min for females, with the exception of boys in wrestling and Greco-Roman wrestling from 11 to 12.9 years of age with 57.4 ml.kg.min. Conclusions: the cut-off points constructed represent a reference to evaluate the aerobic power and qualify the aerobic physical fitness level of the athletes, according to the sport practiced and the individual characteristics of the subjects.
... Although instability core training (ICT) has demonstrated its effectiveness in improving balance ability across various sports, its speci c impact on paddling performance in kayakers, particularly young male Chinese kayakers, remains insu ciently explored. In addition, adolescence is a critical developmental period during which athletes experience signi cant increases in growth and sex hormone secretion, leading to notable improvements in the vestibular, visual, and proprioception systems for balance ability [57]. However, international competition statistics reveal signi cant gaps in both balance ability and paddling performance between young male Chinese kayakers and their world-class counterparts [58,59,60,61,62]. ...
Background: Instability core training (ICT) has been widely used in various sports as a training method to enhance athletes' balance ability and athletic performance. The study aimed to examine the impact of ICT performed on unstable surfaces (BOSU balls, Swiss balls, and Wobble boards) versus traditional core training (TCT) performed on stable surfaces (floor and bench) on balance ability and paddling performance among young male Chinese kayakers. Method: A randomized controlled trial (RCT) recruited 63 eligible kayakers aged 16-19 years from the Nanchang Yao Lake kayaking training base in Jiangxi province, China. Participants were randomly assigned to the ICT group and the TCT group. Both groups completed a 12-week core training program consisting of 1-hour sessions, 3 times/week. Static balance ability was assessed using the Flamingo Balance Test (FBT), while dynamic balance ability was measured using the Star Excursion Balance Test (SEBT). Paddling parameters were evaluated using the average stroke power and stroke rate for the men’s k-1 200m land dynamometer/ergometer sprint tests.Statistical analyses were conducted via multivariate analysis of variance (MANOVA), with the significance level set at P<0.05. Results: The analysis for within-group effects demonstrated statistically significant improvements in static balance ability, dynamic balance ability, average stroke power, and stroke rate variables between the pre-test and post-test in both the ICT and TCT groups (p<0.05). No statistically significant differences were observed in the pre-test (p>0.05) for between-group effects. In contrast, statistically significant differences were found between the ICT and TCT groups in the post-test for all balance ability and paddling parameter variables (p<0.05). Conclusion: The findings suggest that while TCT significantly improves balance ability and paddling performance, ICT is more effective than TCT over a 12-week intervention among young male Chinese kayakers. Therefore, it can replace TCT, as it promotes better improvement in balance ability and paddling parameters for young male Chinese kayakers. Trial registration: The full name of the registry: Effect of instability resistance training on balance, core muscle strength, and athletic performance. The trial registration number is NCT06432595. The date of registration is 07/01/2024. The trial registration platform is ClinicalTrials.gov PRS (https://clinicaltrials.gov/)
... Among these strategies, biobanding has proven effective by grouping players according to their biological maturation rather than chronological age, allowing for a fairer assessment of potential talent [11]. Complementing this approach with technical, tactical, and psychological evaluations could optimize the identification and development of talent in the long term [37]. ...
Background: Early-maturing players tend to have physical advantages during formative stages, but it remains unclear whether these advantages translate into long-term professional success. This study examines how biological maturation influences participation and career trajectories in youth football. Methods: Anthropometric and competitive data were collected from 47 players (13.53 ± 1.08 years) in a top-tier academy during the 2010–2011 season. The maturation status was assessed using the Tanner–Whitehouse II RUS method, and the career outcomes were tracked in 2024–2025. Results: Early-maturing players showed higher anthropometric values and greater participation. However, late maturers were more likely to reach professional football (p = 0.003), with all players competing in the top five European leagues belonging to the late-maturing group. Conclusions: Early maturation does not guarantee professional success. Strategies such as bio-banding and personalized training can reduce biases and support talent development, highlighting the need for a more holistic approach to player evaluation.
... Maturation can be defined in terms of status, timing, and tempo. Status indicates the stage of maturation at the time of observation (e.g., prepubertal, pubertal, postpubertal), timing refers to the age at which particular events, related to maturation occur (e.g., age at peak-height velocity), while the rate at which maturation progresses is referred to as tempo (22). These factors can vary significantly between individuals, and the rate of change of an individuals' own progression toward adulthood can vary greatly over time. ...
The purpose of this study was to examine (a) maturation status distribution across intercounty underage Gaelic games development squads and (b) differences in physical performance metrics relative to maturation status. The study is the first to assess physical performance metrics in intercounty development squad Gaelic Games players, with reference to maturation status. The Khamis & Roche method was used to establish maturation status in 254 male U15 and U16 Gaelic Games development squad players. Tests for lower body power (countermovement jump [CMJ] height), linear speed (10, 20 m), upper body strength (maximum chin-up test), and aerobic endurance (GAA modified Bronco) were conducted. One-way multivariate analysis of variance and analysis of variance were conducted, with an alpha level of p < 0.05 set to determine statistical significance. In both U15 and U16 groups, early developers (EDs) comprised 64.9 and 64.0%, respectively, while on-time (OT) developers comprised 31.5% (U15) and 33.7% (U16), and late developers (LDs) comprised 3.6% (U15) and 2.3% (U16). For U15, ED exhibited significantly faster 10 m speed than LD (p = 0.045) and faster 20 m speed than both OT (p = 0.007) and LD (p = 0.006). After post hoc tests for U16, CMJ scores showed no significant differences (p > 0.05), while U16 ED and OT displayed faster 20 m speed than LD (p = 0.023, p = 0.024, respectively). Coach education around growth and maturation and strategies such as biobanding should be used in talent development settings. Practitioners should interpret speed times relative to maturation status as opposed to chronological age.
... To mitigate the developmental disadvantages faced by relatively younger or late-maturing players within such systems, several alternative strategies have been proposed. One practical approach to addressing these challenges is bio-banding, which groups athletes based on their biological rather than chronological age (53,54). Bio-banding aims to create more equitable and developmentally appropriate opportunities for all players, regardless of their birth date or maturation rate (55,56). ...
Purpose
Publications from recent years suggest that the biological developmental stage of underage athletes has a significant impact on their athletic performance. This scientific study is the first quantitative attempt in Austria to investigate the impact of the relative age effect and biological maturity on the physical performance of young elite soccer players.
Methods
Birth data from a total of 98 male players in the U13 to U18 age groups of a first-division Austrian soccer club were collected. By measuring height, sitting height and body mass, the individual biological age was calculated using the Mirwald equation. The athletes underwent a standardized battery of tests, which included assessments of speed, strength and endurance.
Results
The results indicate a significant effect of the relative age effect on player selection in the U14 and U15 teams (p < .05), which diminishes with increasing player age. Compared to typical Austrian adolescents of similar age, U13, U14 and U15 players demonstrate a higher level of biological maturity (p < .05). Correlational analyses revealed that the maturity offset, reflecting the time before or after the greatest individual growth spurt, was positively related to eccentric hamstring strength (r = 0.82) and vertical jumping ability (r = 0.61) and positively related to sprint performance over 5, 10 and 20 m (0.62 < r < 0.69; all p ≤ .001).
Conclusion
Biological maturity and the associated anthropometric adaptations are decisive for athletic performance. The study supports the notion that biologically more mature players achieve better athletic performance than less mature players, especially before the onset of puberty.
... A traditional underlying principle for annual age grouping in youth soccer is that children of a similar age will be of similar sizes and abilities and, as such, it will provide developmentally appropriate settings for all learners. Over the last two decades, however, a growing pool of literature has showed maturation status does not necessarily correspond to the chronological age of players (65), and thus maturity-associated differences might contribute to RAEs. Indeed, research has showed that there can be up to five years difference in biological age between those in the same chronological age, which can lead to later maturing players being systematically left out of academies, particularly those who are relatively younger (66). ...
Introduction
Despite its widespread prevalence in youth soccer, there seems to be no widely implemented intervention to moderate or overcome Relative Age Effects (RAEs). The purpose of this study was a call to action for stakeholders to propose relative age solutions to the Royal Netherlands Football Association (KNVB).
Methods
The call to action consisted of a standardised, open-access questionnaire that contained questions focussed on: (a) the mechanisms of the proposal, (b) hypothesised effects, and (c) reference to empirical findings.
Results
Following the initial screening of 185 submissions, a total of 143 eligible proposals were included. Each proposal was categorised by two project members based on a taxonomy to classify different approaches designed to reduce RAEs by: (a) altering the behaviour of observers, (b) implementing rules when selecting teams, or (c) adjusting competition structures. From this, 13 lower-order independent solutions were categorised.
Discussion
Interestingly, whilst no new suggestions outside the existing literature were proposed in any of the submissions, only two have been empirically tested in soccer. Overall, the results present a useful first step in identifying possible relative age solutions. Due to the number of proposed solutions and their anecdotal nature, the next step for the KNVB was to utilise the knowledge of experts in the field via an adapted e-Delphi study to identify the most effective and feasible solutions to implement in practice (Part Two).
... This suggests that their success may be largely dependent on their physical attributes, despite coaches emphasizing a holistic evaluation that includes technical and tactical skills. Efforts to mitigate RAE and maturation disparities have included grouping players by stature, weight, biological age, or MS (bio-banding) [44][45][46][47] using talent identification strategies [48] like dressing the athlete in a colored vest depending on their state of maturity, changing the start dates of the sport season [49][50][51], rotating the cutoff dates [49,52], and constructing a narrower time sports categories or others [53]. Recently, Helsen, Thomis, Starkes, Vrijens, Ooms, MacMaster, and Towlson [30] proposed reallocating youth players based on Estimated Developmental (ED) age, calculated from mean stature growth curves. ...
This cross-sectional study aims to clarify the relationship between coaches' decisions and players' relative age, biological maturation, and experience when identifying Under-14 (U14) players for the District and National Teams. Methods: A total of 360 male soccer players participating in the U14 national inter-association tournament, Lopes da Silva, were assessed. Birth dates were recorded, and players were categorized by birth quarter. Anthropometric measurements, fitness level (handgrip strength), and success indicators (performance evaluated by the coach, minutes played, and selection for the National Team) were documented, Maturation status was determined using bone age. Results: The majority of the sample was born in the 1st and 2nd quartiles regardless of maturation status. Morphological and functional differences between players born in different quartiles were no longer significant after controlling the effect of bone age. Late-maturing athletes played significantly fewer minutes. Among the players selected for the National Team, 89.9% were early or on-time maturers, and 92.9% were born in the first or second quartile of the year. While previous studies have shown reduced variability between bone and decimal age in the third and fourth quartiles, our findings indicate greater variability across all birth quartiles. Conclusions: Maturation status and relative age effect are crucial factors influencing coaches' selection decisions. These findings highlight the need for a more equitable approach to talent identification, which should include track maturation bias avoiding the pursuit of short-term success and promoting long-term development programs for young soccer players. Undoubtedly, maturation status and relative age effect (RAE) play a significant role in a coach's decision-making process.
... Jovens da mesma faixa etária podem estar em diferentes estágios de maturidade, com alguns amadurecendo mais rapidamente que outros. Essa variação biológica afeta a performance, a identificação, a seleção de talentos e a prescrição de treinos (Lloy et al., 2014;Malina et al., 2015;Cumming et al., 2017;Malina et al., 2019). ...
A maturação é um processo biológico que leva o organismo ao estado maduro (adulto) e impacta diretamente na formação esportiva de jovens atletas. Este estudo descritivo avaliou a maturação biológica de 1118 jovens atletas de basquetebol (86% masculino; idade cronológica de 13,2 ± 2,0 anos (meninos) e de 12,4 ± 2,7 anos (meninas); 80,9% da região Sudeste). Os dados foram coletados por meio da plataforma digital BioFit®. As informações dos atletas (data de nascimento, estatura, massa corporal) e a estatura dos pais biológicos foram fornecidas pelos participantes. Foram calculados o percentual atingido da estatura adulta predita (%EAP) – Método Kamis-Roche e a idade prevista do pico de velocidade de crescimento (PVC) – Método Maturity offset. Quanto ao status maturacional, 42,8% dos meninos e 24,4% das meninas tinham maturação avançada. A estatura adulta predita foi de 186 ± 8,5m (1,58 a 2,13m) e de 169 ± 6,6m (1,54 a 1,90m) nos meninos e meninas, respectivamente. No grupo masculino, 42,6% estavam no percentil 90 da estatura atual e 48,5% da EAP. Quanto às meninas, 29,5% estavam no percentil 90 da estatura atual e 32,1% da EAP. A idade do PVC foi de 13,5 ± 0,5 anos nos meninos e 11,8 ± 0,6 anos nas meninas. Conclui-se que a plataforma BioFit®️ é uma ferramenta de fácil acesso e que fornece resultados importantes para a compreensão do estado de crescimento e maturação biológica de jovens basquetebolistas.
... Jovens da mesma faixa etária podem estar em diferentes estágios de maturidade, com alguns amadurecendo mais rapidamente que outros. Essa variação biológica afeta a performance, a identificação, a seleção de talentos e a prescrição de treinos (Lloy et al., 2014;Malina et al., 2015;Cumming et al., 2017;Malina et al., 2019). ...
... It can identify the athlete's current weaknesses and focuses, and guide the athlete which aspects need to be improved or strengthened, so as to develop targeted training methods, and allow the athlete to break through the training goals in a short period of time [7][8][9]. In addition, it can not only help coaches set goals and stage plans based on athletes' abilities and goals, but also adjust and optimize training plans based on real-time monitoring data, specific performance, etc., to achieve the improvement of athletes' technical abilities in track and field [10][11][12][13]. Although machine learning technology can provide accurate sports information for coaches' reference, it is also necessary to focus on manual intervention when applying this technology, still focusing on the guidance of professional coaches, supplemented by intelligent devices, and do not put the cart before the horse [14][15][16]. ...
Big data science is a complexity science produced in the new era, and machine learning models belong to its main branch, which has characteristic methodological features and provides new ideas to scientifically solve the personalized formulation of training programs in track and field training. In this paper, firstly, the athletes’ sports data are collected by installing sensors in the key sports parts of the athletes, then the real-time state estimation of the athletes’ sports data is given by Kalman filtering, and the estimation is optimized by microelectromechanical technology. The obtained solution results are inputted into the important movement joint model of the human body so as to realize the motion capture of track and field athletes. Based on this, a personalized training model for track and field has been constructed using an ant colony algorithm. The generation of a personalized training plan is varied into an optimization problem with constraints, containing discrete and continuous variables. Then, the method of adaptation evaluation with constraints and the method of updating related solutions were proposed, thus completing the construction of the machine learning model. The experimental group improved much more in track and field events than the control group, and the experimental group improved 24.96% more in girls’ shot put. It shows that the training program developed through the personalized training model based on machine learning is more in line with the different students’ own needs, and the training program generated based on the machine learning method can provide track and field athletes with more efficient and personalized guidance, which verifies the effectiveness of the model constructed in this paper through the practice of the method and the design of the experiment.
... 18 Based on PHV occurring between 88-95% of %PAH, percentages below 88% indicate pre-PHV and above 95% post-PHV. 20 Identifying the timing of PHV and maturity status of athletes allows strength and conditioning coaches to identify possible timeperiods of rapid growth, consider selection biases and modify training sessions and programs to enhance performance and reduce the risk of injury. Therefore, in the context of New Zealand nationallevel youth basketball players the aim of this study was to (i) quantify anthropometric and performance traits; (ii) describe relationships between maturation and performance characteristics; and (iii) outline the practical implications and programming considerations for strength and conditioning coaches. ...
The purpose of this study was to (i) describe the anthropometric and performance characteristics of New Zealand national level youth basketballers and (ii) examine the relationship between maturation and these characteristics. One hundred and eighty-nine Under 14 and U15 basketball players, boys (n=100; age=14.1±0.5 years; height=178.3±9.0 cm; body mass=70.0±16.0 kg) and girls (n=89; age=14.1±0.7 years; height=169.8±7.6 cm; body mass=65.2±12.3 kg) participated in the study. Anthropometric variables were measured to determine maturity timing and status. Horizonal and vertical jumps, change of direction agility and speed were assessed for physical performance. Differences in performance tests between the boys and girls were assessed via independent samples T-test and linear regression analyses were performed to assess if %PAH (predictor) was associated with each anthropometric or performance variable (outcome). There were significant differences between boys and girls for all anthropometric and performance tests favouring boys (ES = 0.33 to 1.47; p < 0.001). Girls were significantly more mature (greater %PAH) than boys (ES = 1.85; p <0.05). In boys, for every 1% increase in %PAH there was a moderate (ES = 0.63 to 0.71) increase in anthropometric measures and mostly small (ES = 0.24 to 0.33) increases in performance measures. In girls, the increase in anthropometric measures was moderate to large (ES = 0.59 to 0.82). These findings demonstrate that maturation was significantly associated with anthropometric and performance variables in boys but only anthropometric variables in girls. Strength and conditioning coaches should be aware of these differences and consider the practical implications that maturation can have in long-term athlete development planning of young basketball players.
... 18 Based on PHV occurring between 88-95% of %PAH, percentages below 88% indicate pre-PHV and above 95% post-PHV. 20 Identifying the timing of PHV and maturity status of athletes allows strength and conditioning coaches to identify possible timeperiods of rapid growth, consider selection biases and modify training sessions and programs to enhance performance and reduce the risk of injury. Therefore, in the context of New Zealand nationallevel youth basketball players the aim of this study was to (i) quantify anthropometric and performance traits; (ii) describe relationships between maturation and performance characteristics; and (iii) outline the practical implications and programming considerations for strength and conditioning coaches. ...
The purpose of this study was to (i) describe the anthropometric and performance characteristics of New Zealand national level youth basketballers and (ii) examine the relationship between maturation and these characteristics. One hundred and eighty-nine Under 14 and U15 basketball players, boys (n=100; age=14.1±0.5 years; height=178.3±9.0 cm; body mass=70.0±16.0 kg) and girls (n=89; age=14.1±0.7 years; height=169.8±7.6 cm; body mass=65.2±12.3 kg) participated in the study. Anthropometric variables were measured to determine maturity timing and status. Horizonal and vertical jumps, change of direction agility and speed were assessed for physical performance. Differences in performance tests between the boys and girls were assessed via independent samples T-test and linear regression analyses were performed to assess if %PAH (predictor) was associated with each anthropometric or performance variable (outcome). There were significant differences between boys and girls for all anthropometric and performance tests favouring boys (ES = 0.33 to 1.47; p < 0.001). Girls were significantly more mature (greater %PAH) than boys (ES = 1.85; p <0.05). In boys, for every 1% increase in %PAH there was a moderate (ES = 0.63 to 0.71) increase in anthropometric measures and mostly small (ES = 0.24 to 0.33) increases in performance measures. In girls, the increase in anthropometric measures was moderate to large (ES = 0.59 to 0.82). These findings demonstrate that maturation was significantly associated with anthropometric and performance variables in boys but only anthropometric variables in girls. Strength and conditioning coaches should be aware of these differences and consider the practical implications that maturation can have in long-term athlete development planning of young basketball players.
... The lack of significant differences might be explained by this small sample, as well as other contextual factors within the academy's selection processes which prioritize game understanding and technical-tactical skills over anthropometrics and physical performance. This is important to consider as growth and maturation have been shown to influence coaches' and decision makers' perceptions of ability/potential and performance (45), with early maturing players in elite academies being perceived as more capable (6) and with greater potential (46), which may also lead to them being promoted in the academy and called up by their state or national team (47). Finally, in the same vein, it seems that the level of maturity has not been very influential on the club's proposal to remain in the academy. ...
This brief research report aimed to analyze the prevalence of asymmetries in players' date of birth, the influence of relative age affects (RAEs) and maturation on players' participation, and the potential maturity biases in performance indicators in a Spanish professional male soccer academy. Maturity status was determined as the percentage of predicted adult height (%PAH). RAEs are strongly represented in the sample as 77% of players were born in the first semester of the year. Relatively older players do not appear to receive significantly more playing minutes, while more mature players showed a higher percentage of playing time in U13 and U14, with no differences in U15 and U16. In other performance indicators, more mature players do not have an advantage when it comes to being considered “promising players”, training and competing with higher chronological age groups and being selected by state teams. Finally, individual maturity level within the team does not appear to be relevant to the club's proposal to continue in the academy. Our results show a strong overrepresentation of players born in the first semester of the year, indicating the presence of RAEs. However, this bias does not translate into significant differences in competitive performance, such as playing time. Conversely, individual maturity status demonstrates a transient effect on playing time in younger age groups (U13 and U14). These findings underscore the importance of understanding the interplay between RAEs and maturity biases in talent identification and development in the highly competitive framework of a professional soccer academy.
... Regarding the player input, the current approach on the selection of incoming players relies on physical attributes, making it susceptible to the relative age effect trap. Alternative methods such as bio-banding (Cumming et al., 2017) for more fair observations at trial-games or longer-term observation based on data may be implemented in the selection process. The results also showed that personal attributes and soft skills were often disregarded in Turkish academies, leading to detrimental effects on the development process and outcomes in the later stages. ...
The management of football academies is a multifaceted process that involves different influential stakeholders. Coaches, as key stakeholders, contribute significantly to the overall success of a football academy. Recognizing coaches’ pivotal role in the developmental journey of young football players, the current study employed the systems approach to explore the management practices of football academies in Turkey, with a particular emphasis on the perspective of coaches. The primary objective was to comprehend the challenges and obstacles confronted by Turkish football academies in terms of management and their implications for the overall efficiency of the academies. Furthermore, the study aimed to delineate the fundamental requirements and necessary services encompassing the input, process, feedback, output, and environmental aspects of the football academy system. Fifteen head coaches of senior teams in the top two divisions in Turkey with previous coaching experience in football academies were interviewed using a semi-structured interview. The results were analysed using qualitative content analysis. The findings indicated that management should prioritise specialised coaching approaches tailored to football academies. Training young football players in academies requires coaches specifically trained for this purpose, as it is a distinct profession from those coaching senior teams. The study proposes a solid recommendation to improve coaching education programs, both in quantity and quality, addressing specific challenges in Turkish football academies. The article ultimately emphasises the importance of adopting a systems theory approach to achieve successful football academy management while accounting for environmental factors to achieve sustainable practices in Turkey's football academies.
... 43 On the other hand, it is recommended to adapt training programmes to individual differences with regard to the maturation, avoiding performance comparisons that may discourage or limit players' development. 44 Incorporating strategies such as bio-banding, which groups players according to the biological maturity status, could provide more equitable and stimulating competitive experiences for both early and late maturing players by setting specific goals. 45,46 Furthermore, regular assessments of maturation in relation to chronological age would be beneficial in talent identification and development programmes, allowing for a reduction in the bias towards more physically developed players. ...
Maturation is one of the determining factors in talent identification and development systems. The aim of the present study was to assess the impact of maturity status and anthropometric variables on the physical performance of young volleyball players. The sample included 278 volleyball players (217 girls, 13.63 ± 1.73 years; and 61 boys, 14.27 ± 1.46 years) who were selected to participate in the 2020–2025 National Programme organised by the Spanish Volleyball Federation. Maturity status was estimated using the Khamis-Roche equation based on the percentage of predicted adult height. The physical tests evaluated were vertical jump, spike jump reach, 3 × 9 and FRAC. The results showed that an advanced maturation is associated with increased physical performance in young volleyball players. Specifically, ‘maturity status’ was strongly and positively associated with the VJ (p < 0.001), SJR (p < 0.001) and 3 × 9 (p < 0.001) tests in both boys and girls, and ‘height’ was associated with the VJ (girls, p < 0.001; boys, p < 0.01), SJR (p < 0.001, both) and 3 × 9 (girls, p < 0.001; boys, p < 0.01). ‘Body mass’ correlated with vertical jump tests (VJ and SJR), especially in girls (p < 0.001). Moreover, the maturity status in relation to age served as a predictor of physical performance in the SJR test explaining up to 57.93% and 62.00% of the variance in boys and girls respectively. Coaches and technical staffs should rethink the tests used in talent identification in order to avoid confusing the player's current potential with the future sporting level through actions such as adapting the training process or implementing educational initiatives in relation to maturation.
... In terms of practical implications, addressing the RAEs require a multi-faceted approach, as recommended by Romann et al. (17). Strategies such as adjusting selection procedures, implementing birth-date banding or bio-banding, and delaying age-based competition until post-maturation could help balance developmental opportunities (49,50). Additionally, fostering the inclusion of teams composed solely of players born in the second half of the year or late-maturing players-as parallel teams to higher-level competitive teams within the academy-could provide appropriate training stimuli tailored to their characteristics, rather than leading to early dropout from the sport. ...
Introduction
The Relative Age Effects (RAEs) are complex, multifactorial phenomena influenced by individual (e.g., maturity status), task-related (e.g., field position or competitive level), and environmental (e.g., coaches' expectations) factors. This cross-sectional study aimed to investigate the relationship between RAEs and the maturity status, field position, competitive level and coaches' expectations within a sample of 1,120 young male Spanish football players [mean age: 13.72 ± 1.40 years; weight: 54.09 ± 11.85 kg; height: 162.11 ± 11.38 cm; years from peak height velocity (PHV): −0.22 ± 1.44], across tree age categories (U12, U14 and U16).
Methods
Data was collected over 10 years (2014–2024), considering the maturity status, estimated using the Mirwald et al. (2002) formula. Physical performance was assessed through tests for strength (1RM), power, speed (30-m sprint), agility (T-test), jumping (CMJ), and aerobic endurance (estimated VO2max). Players' field positions and coaches' efficacy expectations about their players were also collected.
Results
A Chi-square (χ²) analysis revealed a skewed distribution across birth quartiles within age categories (p < 0.05). Pearsons' correlation and linear regression analyses showed significant relationship between relative age and maturity status (r = 0.91; R² = 0.84). The RAEs were more pronounced at higher competitive levels, while the distribution bias in playing positions was comparable to the overall sample, with the exception of goalkeepers in the U12-14 categories. ANOVA results tend to a higher physical performance and coaches' efficacy expectations for players with higher RA in the U14 and U16 categories.
Conclusion
This study confirms the presence of strong RAEs over the past decade in youth football players from U12 to U16. Individual and environmental factors, such as advanced maturity status, the intensified selection processes at higher competitive levels, an increased physical performance and higher coaches' efficacy expectations, may contribute to RAEs in a complex and interdependent manner.
... In this sense, it addresses concerns about talent identification processes, which often (and wrongly) allocate more resources to early maturing athletes, to the detriment of late maturers who may have greater longterm potential (Cumming et al., 2017). This study also provides a deeper understanding of the different components of perceived competence in ice hockey. ...
Purpose : One of the most critical periods in a player’s development is adolescence when major competitions and hormonal changes occur. However, very few studies have investigated ice hockey-related performances during this period and whether players’ perceptions of competence also evolve. Therefore, this study aimed to measure the progression of players’ different anthropometric, physiological, and psychological attributes as a function of their pubertal status and team selection during a competitive ice hockey season. Methods : Forty male (M age ± SD = 13.81 ± 0.41 years) and 38 female (M age ± SD = 14.97 ± 0.92 years) players were monitored as part of a selection process for a national team between July 2021 and January 2023. Participants completed off-ice and on-ice fitness tests three and two times, respectively, and filled out the Self-Perceived Ice Hockey Competence Scale twice. Results : players further along in their pubertal development are stronger and more powerful, but perceptions of competence remain stable over the same period, regardless of selection or pubertal status. Conclusion : The study allows us to better understand the evolution of actual and perceived competence during a key period in high-level ice hockey development and to differentiate the progress of youngsters selected or not for a provincial team.
... The typical purpose of maturity matched bio-banded soccer formats are to create an equitable playing environment (Cumming et al., 2017;Malina et al., 2019;, which is devoid of recipient players possessing temporary, maturity-related (physical (Lovell et al., 2015;Towlson et al., 2017), anthropometric (Towlson et al., 2018), technical-tactical and psychological (Cumming et al., 2018;Towlson, Salter et al., 2021)) (dis)advantages which are considered important during talent identification (Larkin et al., 2017;Towlson et al., 2019), and can influence individual match-play responses during mixed maturity matchplay and training (Cumming et al., 2018;da Costa et al., 2023;Lovell et al., 2019). This is a particularly important phenomena to consider, given that academy soccer practitioners are likely to (de)select players based on greater emphasis on specialist physical/technical position-specific attributes as players navigate the development pathway towards professional status (Towlson et al., 2019). ...
The timing of the adolescent growth spurt (i.e. peak height velocity [PHV]) varies greatly, causing significant differences in maturity-related anthropometric and physical development among chronologically age-categorised youth soccer players. These differences can lead to a maturity-selection bias favouring early maturing players. Using fifty-three players from two professional Scottish soccer academies,
this study examined the effects of team size (4v4, 5v5, and 6v6) and bio-banding (i.e. grouping players by maturity status) on players technical (i.e. touches, releases, possessions), physical (i.e. distance covered, accelerations/decelerations), and psychological (i.e. confidence, competitiveness, positive attitude) performance during small-sided games, using foot-mounted inertial measurement units (F-IMU)
and coach observations. Data were analysed using multivariate ANOVA. During maturity-matched games, technical actions decreased as team size increased. More mature players displayed greater technical actions in 4v4 compared to 6v6. Maturity-mismatched games revealed significant technical action differences for less mature players, particularly in 4v4 formats. More mature players covered greater high-intensity distances in maturity-matched and mismatched 6v6 games. Psychological scores were higher for more mature players in smaller team sizes (4v4), whereas less mature players showed consistent psychological scores across all formats. Smaller team sizes and maturity-matched bio-banding formats enhanced technical actions and psychological characteristics, particularly for more mature players.
... Bio-banding, where players are grouped by biological maturity status rather than chronological age, aims to reduce inter-individual variation in maturity within groups, potentially creating a more balanced training environment for players with different maturity statuses. This approach can help mitigate disadvantages for late maturers by ensuring they compete with peers with similar levels of biological maturity status [19,20]. ...
... Another method is the one called bio-banding, which aims to separate earlymaturing or late-maturing athletes in different categories [114,115]. Bio-banding is the process of grouping athletes based on attributes associated with growth and maturation, rather than chronological age [116]. The procedure is similar to detection days organized by trimesters of birth. ...
The scientific literature on talent identification is extensive, with significant advancements made over the past 30 years. However, as with any field, the translation of research into practice and its impact on the field have been slower than anticipated. Indeed, recent findings highlight a pervasive relative age effect, the effects of maturation being often overlooked, disparate populations between young and senior performers, and a necessity to embrace a holistic approach. However, simple elements can be implemented to avoid some of these known biases. This review synthesizes recent advancements, critically examines key elements to consider in talent identification, and proposes promising avenues for enhancement. These include (1) understanding and illustrating early performance influences, (2) implementing individualized performance trajectory models, (3) applying corrective adjustments based on relative, biological, and training age, and (4) improving estimation of potentials through a holistic approach that integrates “life pathways”. In light of these necessary improvements, it seems opportune to propose a semantic shift to generate a change in both conceptual and operational paradigms. The proposed terminology of “estimation of potential” is based on a semantic and mathematical definition, which operationalizes its conceptualization. This study suggests that understanding the trajectories of transitions from youth to senior categories in each sport, coupled with a holistic approach centered on individual performance progressions across the three ages, would be a possible path toward estimating potential.
... Research has explored its prevalence in both team and individual sports [10][11][12], assessed its influence within specific competitions [13,14], and examined the extent to which factors such as gender, age, or competition categories in clubs and federations shape its impact [15,16]. Moreover, some studies have proposed interventions aimed at mitigating its potential consequences [17][18][19]. Recently, there has been a growing focus on understanding the relationship between RAE and competition performance, with the aim of gaining deeper insights into how this phenomenon influences athletic outcomes [20][21][22]. ...
This study investigated the relative age effect (RAE) in junior padel players participating in the 2024 European Junior Championships by Teams. The sample included 285 athletes (165 boys from 16 boys’ teams and 120 girls from 12 girls’ teams). Dates of birth were categorized into quartiles, and data analysis employed Chi-squared goodness-of-fit tests, Fisher’s exact goodness-of-fit tests, Chi-squared tests, Fisher’s exact tests with Monte Carlo correction (95% CI), and Spearman correlations. The results showed no consistent RAE overall. However, in boys, players born in Q1 (CSR = 2.2) and in the last year of eligibility (CSR = 2.0) were more prevalent in higher-ranked teams. Position directly correlated with quartile (boys: p = 0.015; girls: p = 0.001) and category year (boys: p = 0.032; girls: p = 0.038). These findings suggest that while RAE was not observed across all junior padel players, boys’ teams, particularly in higher ranks, exhibited trends favoring early birth quartiles and the final year of eligibility. Such patterns may influence competitive performance and talent identification. Further research is needed to understand the implications of RAE in youth sports, particularly regarding talent development and team selection processes.
... However, the simultaneous increase in both fat and muscle mass can elevate energy demands, potentially reducing endurance efficiency during prolonged activities [55]. Early-maturing athletes often exhibit increased confidence stemming from their physical advantages, which in turn, positively influences their performance outcomes [56]. In contrast, late-maturing athletes may face reduced self-esteem or frustration, potentially hindering their endurance and power performance [57,58]. ...
Objectives: There is a lack of studies that investigate the relationship between anthropometric profiles, biological maturity, and specific physical performances in young male basketball players. This study aimed to evaluate the development of anthropometric characteristics and physical performance across different age and maturity groups among male basketball players in Palestine, as well as to identify the anthropometric factors influencing physical performance within this population. Methods: A total of one-hundred-fifty male basketball players, aged 12 to 16, participated in this study. The players were categorized by age groups (U-12 to U-16) and divided into five maturational groups based on their maturity offset, ranging from −1.5 to 2.5 years relative to peak height velocity (PHV). The measurements included anthropometric variables and physical performance, such as sprinting performances, jumping ability, agility tests, and maximal aerobic capacity. Statistical analyses, including a full model and multiple regression analysis, were conducted to identify the anthropometric parameters that significantly influenced the performance variables. Results: Anthropometric development, particularly lower-limb length, significantly influenced vertical jump performance, while increases in body composition and fat mass negatively impacted sprinting and strength test outcomes. Our study confirms that maturity status plays a crucial role in determining physical performance among young Palestinian basketball players. Early-maturing players generally demonstrated greater strength and endurance, whereas late-maturing players excelled in agility and speed. The full model and the multiple equations were used to determine the determinants of physical performances according to anthropometric variables. Conclusions: The findings show that performance benchmarks based on age and maturational groups may contribute to a better understanding of training protocols and talent identification for young male basketball players in Palestine, as well as support the development of strategies for physical activity practice.
... In this respect, during the last decades, researchers have tried to determine the influence of biological maturation on these factors to improve the processes of talent identification (Albaladejo-Saura et al., 2021). This study on anthropometry-based indicators of morphology and maturity status could potentially enhance talent identification, sports specialization, and the early categorization of young athletes (Cumming et al., 2017;Malina et al., 2012). Indeed, recent studies have emphasized the importance of anthropometric evaluation in delineating the morphological and performance traits of adolescent combat athletes (Toselli et al., 2021). ...
In the last couple of years, unsupervised machine learning has emerged as a strong tool for the analysis of complex patterns and relationships in data. Its application in the assessment of anthropometric characteristics and biological maturity is of great value for gaining insight into athlete development and performance. The present study intended to characterize the body composition, morphology and maturity status of young athletes; classify them according to anthropometric measurements; and predict their adult stature. The sample included 138 male athletes of varying regional settings in Bangladesh, all of whom were aged between 12 and 14 years. The anthropometric measurements used are those prescribed by ISAK. Key variables involved were body mass, stature, girths, and skinfold thickness. PAM clustering was used to identify patterns; morphological variable associations with maturity status were determined using statistical methods. Results identified two clear clusters, where Cluster 1 was dominated by late-maturing athletes and Cluster 2 was comprised of averagely matured athletes. Cluster 2 athletes were more physically robust, higher in body mass, and more advanced in maturity, hence having greater athletic potential. These findings constitute an effective contribution to the identification of talented athletes and specific intervention strategies for supporting athletic development in Bangladesh.
Puberty is a critical period for young athletes, characterized by significant physical, psychological, and social changes. During puberty, young athletes experience the adolescent growth spurt at the same time as intensified training regimens, which can affect performance, injury risk, and overall health. Systematic training can improve physiological and performance outcomes, but the increased training volume and changes to the body during adolescence can also heighten the risk of injuries. This article discusses the injury risks associated with adolescent growth and provides comprehensive recommendations to mitigate these risks. Key recommendations include limiting training hours to the athlete's age, monitoring growth and maturation to adjust training loads and content, and incorporating and modifying consistent strength and conditioning prescriptions. In addition, optimal nutrition, sleep, and interdisciplinary planning among coaches, parents, and stakeholders should be emphasized to support young athletes' holistic development and well-being during the adolescent growth spurt.
Background Young soccer players, club professionals and soccer academies require to monitor and evaluate the state of maturity. This will allow decisions to be made in the process of selection and detection of sports talent. Objective a) To determine which of the two equations (Mirwald and Moore) is more adequate to analyze physical performance in young soccer playersnd b) to propose reference values to evaluate the physical condition of young Chilean soccer players according to maturity stage. Methods A descriptive cross-sectional study was carried out in 302 young Chilean soccer players between 11 and 16 years of age. Weight, standing height, sitting height and seven physical tests were evaluated: Hand grip strength (HGS) [(right and left], explosive strength [horizontal jump (HJ), squat jump (SJ), and countermovement jump (CMJ)], agility (Illinois and 5x10 repetitions) and aerobic fitness (distance in meters and VO2max). Maturity status (MS) was estimated using two equations: Mirwald and Moore for men. Percentiles were calculated using the LMS method (L = lambda for the skewness; M = mu for the median; S = sigma). Results MS was estimated by Mirwald at 13.8 ± 0.60 years and by Moore at 13.18 ± 0.47 years. HGS (right and left) were higher by Moore's method from 1 to 4%. With the explosive strength tests (HJ, CMJ and SJ), the values were higher from 1 to 3%. With the agility tests (Illinois and 5x10repetitions), the explanatory power was higher from 2 to 4%. With the aerobic fitness values (meters run and VO2max), the values were higher from 1 to 3% in relation to the Mirwald method. Percentiles (P3, P5, P10, P15, P25, P50, P75, P85, P90, P95 and P97) were developed for the physical tests according to Moore's MS (-2APHV, -1APHV, 0APHV, +1APHV and + 2APHV). Conclusion Moore's equation is more adequate than Mirwald's to analyze physical performance in young Chilean soccer players aged 11 to 16 years. Percentiles based on maturity status can be used to categorize, monitor and evaluate physical performance during the growth and development of young soccer players.
In most competitions, a (bi)annual age-grouping procedure is implemented for
logical organization and to reduce the physical development differences between
competitors (1). However, an athlete’s maturation does not necessarily correspond to their chronological age at the individual level (2). This phenomenon, known as the Relative Age Effect (RAE), refers to the advantages or disadvantages athletes may experience due to differences in physical and biological maturation within the same age category. Therefore, the RAE has been widely studied in sports performance in initiation categories (3). The aims of the present study were twofold: first, to analyze the presence and magnitude of the RAE in the Catalan regional athletics championships and, second, to determine the influence of the birth quarter on the likelihood of achieving better results. The analysis included a total of 2,241 athletes of both sexes. The 2023 season championships were evaluated across the U12 to U20 categories, covering sprints and hurdles, middle-distance, long-distance, and race walking, jumps, and throws. Data were obtained from the Catalan Athletics Federation webpage. Chi-square tests (x2) were used to analyze associations, and
the odds ratio (OR) was calculated to determine probabilities. Our results showed a
significant statistical association between the position obtained and the birth quarter for both women (p = 0.028) and men (p = 0.007). In their first year in the category, those born in Q5 were 12.38 times more likely to win a medal in jumping events than those born in Q8 (p = 0.022). Similarly, those born in Q5 were 3.11 times more likely to win a medal in throwing events than those born in Q8 (p = 0.045). In the second year of the category, it was observed that those born in Q1 were 2.72 times more likely to win a medal in jumping events than those born in Q4 (p = 0.017). These results suggest that the RAE can have a significant impact on athletic performance, possibly due to the physical and cognitive advantages associated with relative maturity. It is important to consider these differences when designing training programs and talent selection processes, as well as the possibility
of organizing categories according to other criteria, such as bio-banding (2).
On behalf of the Strength and Conditioning Society (SCS), we are pleased to present the abstracts submitted for the SCS 7th Annual Meeting. The event was held at the Universidad Católica de Murcia (UCAM) headquarters in Murcia, Spain, on 9–11 October 2024, and comprised several invited sessions by international and national speakers on a variety of topics related to biochemistry and exercise physiology, strength and conditioning practices and their application to health, injury prevention, and sports performance. These included strength training in high-performance sports, sport science and training–competition load management in elite environments, biochemistry and exercise physiology and prescription, nutrition and biomechanics, among others. The conference also included practical workshops by renowned academics and practitioners on eccentric training, change of direction ability, and strength and power training in professional team sports, combat sports, and ergospirometry and exercise prescription in specific populations. Finally, the event disseminated up-to-date strength and conditioning research by providing practitioners and researchers with the opportunity to present their most recent findings. All abstracts presented at the SCS 7th Annual Meeting can be found in this Conference Report.
Background: The lack of a structured futsal curriculum for children aged 6-8 years in futsal clubs, especially in Super Junior Club Malang, causes limitations in developing techniques, skills, and long-term athlete development. Objective: This is for developing a futsal curriculum model at the Super Junior Club of Malang City, which is presented as a curriculum for learning. Methods: The research and development model used in the study is to develop a curriculum model. Development research This uses the ADDIE method with steps study as follows: 1) analysis, 2) design, 3) development, 4) implementation, and 5) evaluation. This is done using a questionnaire and sheet valuation. Results of interviews that have been done do Not yet exist. Possible guidelines and curricula can be used to create training programs. Excess from study This includes: 1) becoming guidelines beginning in making training programs, 2) making things easier for trainers to determine goals in the training program. The weaknesses of the study include: 1) limitations in election group age certain, 2) not too many training models, and 3) the curriculum must keep updating along with the development of futsal sport. Result: Based on the results, an analysis by the validator is obtained. The average percentage was 88.07% from material validators, 97% from media validators, and 94.7% from group tests conducted on Malang City Super Junior Club students. Conclusion: Curriculum Model Development Sport Futsal Age 6-8 Years at the Malang City Super Junior Club is considered worthy of use. Future research could explore the effectiveness of implementing this futsal curriculum in improving players' technical and tactical skills and examine its impact on the long-term development of early athletes in various clubs and regions.
Surveys can efficiently generate big datasets, but they can misrepresent participants' understandings. Our article discusses the potential for surveys to produce 'methodological artifacts' when measuring complex phenomena, via a project exploring parents' understandings of biobanding in youth sport. Although 99.5% of survey respondents (n = 389) indicated that they understood biobanding, follow-up interviews with 11 participants revealed this to be spurious data. This contrast between survey and interview responses highlights the limitations of surveys in capturing nuanced understandings. We argue that this misalignment between the object of study and the chosen method results in findings are 'methodological artifacts' rather than reasonable representations of social life. As such, the study demonstrates how seemingly simple survey questions about biobanding were actually attempting to tap into the complex processes of human knowledge production. Around this finding, we build an accessible and practical discussion of research philosophy that leads us to caution against developing knowledge claims based on 'wonky' epistemological foundations. And we encourage colleagues to carefully consider how their chosen methods might usually frame but also misrepresent, or unduly distort phenomena under investigation. We conclude by calling for deeper reflection on methodological choices, particularly when research is guided by the constraints of academic structures rather than scientific principles.
Orienteering is a sport where participants must choose the best route between control points marked on the map, combining it with their displacement capacity. It combines endurance running with mental capacity. As in other sports, age can be a determinant in defining differences among youth runners. In this research, the hypothesis is that older orienteers will show better performance than younger orienteers within the same competitive group, for both girls and boys. Overall, official results of the FEDO (Spanish Federation of Orienteering) in long and middle-distance events, from 2005 to 2023, have been analyzed (sprint format events were excluded). Different categories from ten to twenty years of age for both sexes were included, and each category was divided into two years (1Y, 2Y) and two semesters (1S, 2S) within each year, creating four independent variables from the combination of year and semester (1Y1S, 1Y2S, 2Y1S, and 2Y2S). A total of 7,731 entries were examined, 4,318 were boys and 3,109 were girls. Descriptive statistics were analyzed for each variable, showing the mean and standard deviation. Normal distribution was confirmed for all variables (p > 0.05). Results showed a significant performance difference in favor of older orienteers in the youngest categories (U-10, M/F-12, M/F-14, and M-16), with these differences disappearing as age and performance increased (M/F-18 and M/F-20). These findings support the research hypothesis and align with other studies where age-related differences have also been found in other sports.
Bio-banding, sprawność motoryczna, cechy somatyczne, trenujący i nietrenujący, prognozowanie dorosłej wysokości ciała metodami Khamisa-Rocha oraz Żarowa, przewidywanie skoku PHV metodą Mirwalda, analiza rozwoju wg wysokości ciała 2,5 letnie badania siatki centylowe
This study aimed to investigate academy football coaches’ perceptions and experiences of managing adolescent growth and maturation within the constraints of an English Premier League academy. Using a longitudinal mixed method design, 98 under 12–16 players were assessed for maturity status, growth velocities and match performance grade. Interviews were conducted in parallel, with their nine respective coaches. The quantitative and qualitative data were then combined to generate a rich, contextualised understanding. One case study is also presented as an archetypal example. Findings are presented in three themes. Coaches described the conflict between the value of winning and player development, difficulties in judging potential and performance, and the challenges of developing players in an elite competitive environment. Findings emphasise the intricacies of managing and developing adolescent athletes in academy football. Coaches in this study were challenged by the individual differences in growth and maturation and the elite, competitive and selective nature of football academies and the constraints of this environment exacerbate these challenges.
Introducción: Durante el periodo de la adolescencia se producen cambios en el cuerpo, siendo importante identificar las diferencias individuales de madurez entre los adolescentes. En el caso de los futbolistas, esto puede generar diferencias en su rendimiento deportivo. Objetivo: Comparar el desempeño físico de jóvenes futbolistas vs escolares (no futbolistas) según edad cronológica y estado de madurez. Metodología: Se efectuó un estudio de tipo descriptivo-comparativo en 139 jóvenes (62 futbolistas con 16,38±1,30 años y 77 escolares con 16,35±1,45años). La selección de la muestra fue de tipo no probabilística por conveniencia. El rango de edad fue entre 14 a 18 años de edad. Se evaluó el peso, la estatura, velocidad 20 metros, salto horizontal (SH), y la prueba de aptitud aeróbica de Leger. Se calculó el índice de masa corporal (IMC), los años de pico de velocidad de crecimiento (APVC), y el VO2max absoluto y relativo. Resultados: Los jóvenes futbolistas presentaron mayor VO2max absoluto y relativo en comparación con sus similares escolares, tanto por edad cronológica y estado de madurez. Hubo correlación positiva significativa (p<0.05) entre la edad y los APVC con el VO2max absoluto y salto horizontal, y negativa con la velocidad de 20 metros. No hubo correlación entre la edad y APVC con el VO2máx relativo (edad y VO2máx, r= 0.10, p=0.023 y APVC y VO2máx, r= 0.07, p= 0.036). Conclusión: Los jóvenes futbolistas presentaron un mejor VO2max absoluto y relativo, SH y velocidad 20m en relación a los no-futbolistas, tanto por edad cronológica y estado de madurez, aunque, el desempeño físico se observa mejor por estado de madurez, especialmente en el VO2max y en el SH. Estos resultados sugieren que los profesionales del futbol deben considerar el control del estado de madurez como una alternativa para categorizar a los futbolistas cuando se evalúa y trabaja el desempeño físico
This study evaluates the accuracy and validity of the Maturo software, an automated tool for estimating biological age and related maturation metrics, in a sample of 103 actively training teenage athletes aged 9 to 17 years. The sample included 76 males (mean age = 11.74 years, SD = 1.55) and 27 females (mean age = 13.95 years, SD = 1.40), all without medical conditions that might impact growth or development. The results were compared to traditional expert evaluations. The Intraclass correlation coefficients (ICCs) and Pearson correlation coefficients demonstrated reliable positive correlations and significant agreement between the Maturo software and expert methods across multiple metrics, such as biological age (ICC = 0.965, R = 0.97), corrected biological age (ICC = 0.973, R = 0.99), predicted adult height (ICC = 0.991, R = 0.99), and percentage of adult height achieved (ICC = 0.955, R = 0.97). The Bland-Altman plots provided additional evidence of the validity of the Maturo software estimations, showing low systematic error in most measures. The linear regression analysis produced excellent adjusted R-squared values, 0.95 for biological age and 0.99 for anticipated adult height. The Maturo approach demonstrated a high level of dependability in classifying teenagers into groups based on their maturity status and timing. The Kappa coefficients of 0.93 for maturity status and 0.82 for maturity timing indicate a nearly perfect agreement with the expert technique. While the Maturo software’s non-invasive nature, cost-effectiveness, and ease of use could make it a potential tool for regular monitoring of growth and maturation in young athletes, its promising results in assessing maturation should be interpreted with caution due to limitations such as sample size and demographic constraints. Further longitude research with larger and more diverse populations is needed to validate these preliminary findings and strengthen the evidence for its broader applicability.
This book presents an integrated, research-driven, collection of 54 evidence-based chapters. Chapters are founded on the research and practical experience of 104 internationally renowned scientists and clinicians, from 25 countries. Each extensively referenced chapter concludes with a bulleted summary and where appropriate is cross-referenced to complementary chapters. The Exercise Science section initially focuses on growth and maturation and the development of motor control, coordination, and muscle strength. Subsequently, molecular exercise physiology, physiological variability, and the perception of exercise are explored and the cerebrovascular, metabolic, endocrine, cardiopulmonary, and neuromuscular responses to exercise are analysed. The Exercise Medicine section opens with a discussion of the role of molecular mechanisms in transducing physical activity and exercise into health benefits. The following chapters analyse physical activity, exercise, and sedentary behaviour and their relationship with cardiovascular health, metabolic syndrome, eating disorders, bone health, diabetes, asthma, cystic fibrosis, cerebral palsy, mental health, and intellectual disability. The Sport Science section reviews bio-banding in youth sport before examining the morphology of youth athletes and analysing the development and trainability of aerobic fitness, anaerobic fitness, speed, and agility. The evidence underpinning resistance, high-intensity, and neuromuscular training is evaluated and overtraining, sleep, temperature regulation, and appropriate assessment, monitoring, and long-term development of youth athletes are discussed. The Sport Medicine section reviews the epidemiology and prevention of injuries before focusing on injuries in physical education classes, and youth sports, and evaluating the role of stretching in injury prevention. The diagnosis and management of injuries to the upper extremity and trunk, the lower limbs, and the head and cervical spine are reviewed. The book concludes with discussions of disability and youth sport, nutrition and eating disorders, dietary supplementation, doping and anti-doping, and safeguarding youth athletes.
It has recently been proposed that the tackle, an integral part of Rugby Union, be banned in school rugby, as a means to reduce the risk of injury. This proposal held that harmful contact should be removed in response to what was termed an unacceptably high-injury risk. Such a ban would represent a significant intervention that could change the nature of Rugby Union. As such, the basis and rationale for such a ban is worthy of critical evaluation. This review aims to describe the research on which such a ban is proposed. It does so through an assessment (identification), estimation (understanding of the magnitude and occurrence) and evaluation (determining acceptability) of the risk before decisions can be made about implementing any risk mitigation strategies. The body of literature describing injury risk, particularly among youths, is indeed thin and fraught with methodological differences that makes definitive conclusions impossible. We describe these, and their implications, arguing that the complete ban on the tackle may be unnecessary in young children, in whom injury risk may not be as high as is often argued, but also that it may have detrimental consequences. Finally, we propose alternative strategies and research questions which must be pursued to effectively reduce risk without creating unintended consequences or changing the nature of the sport.
When placed into age groups for junior sporting competition, the relative differences in age between children leads to a bias in who is evaluated as being talented. While the impact of this relative age effect (RAE) is clear, until now there has been no evidence to show how to reduce it. The aim of this study was to determine whether the selection bias associated with the RAE could be reduced. Talent scouts from an elite football club watched junior games and ranked players on the basis of their potential. Scouts were allocated to one of three groups provided with contrasting information about the age of the players: (1) no age information, (2) players' birthdates or (3) knowledge that the numbers on the playing shirts corresponded to the relative age of the players. Results revealed a significant selection bias for the scouts in the no-age information group, and that bias remained when scouts knew the players' dates-of-birth. Strikingly though, the selection bias was eliminated when scouts watched the games knowing the shirt numbers corresponded to the relative ages of the players. The selection bias associated with the RAE can be reduced if information about age is presented appropriately.
The relative age effect (RAE) has been thoroughly examined and shown in many sporting contexts, and the grouping of athletes into weight categories may provide a partial solution to this problem. Thus, the aim of this meta-analysis was to verify if weight categories used in combat sports prevent athletes from the RAE, including an analysis separating the athletes by sex. After initially identifying 141 studies, 135 were excluded. The birth dates of combat sports participants in six studies were used to perform a meta-analysis. Odds ratios and 95 % confidence intervals were calculated. The main result of this investigation was the presence of RAE male and female groups and the male-only group of senior (professional/Olympic) athletes, but not the female-only group of senior and cadet or junior athletes. Thus, the RAE in combat sports is more prominent at the senior level and in male compared to female combat sports athletes.
Background
Basic understanding of motor control and its processes is a topic of well-known high relevance. During adolescence walking is theoretically a well-achieved fundamental skill, having reached a mature manifestation; on the other hand, adolescence is marked by a period of accelerated increases in both height and weight, referred as growth spurt. Thus, this period was chosen as a controlled and natural environment for partially isolating one of the factors influencing motor development (segment growth). The aim of the study was to compare gait performance of growing and not growing male adolescents during walking in single task (ST) and dual task (DT), in order to study which are the modifications that motor control handles when encountering a sudden change in segment length.
Methods
19 adolescents were selected as growing adolescents (they showed a height increase greater than 3 cm in 3 months). A group of BMI-matched peers were selected as not growing adolescents (they showed a height increase lower than 1 cm in 3 months). Measures of acceleration of the trunk (L5 level) were collected using one tri-axial wireless inertial sensor. The participants were asked to walk at self-selected speed back and forth four times in a 10 m long corridor in ST and DT conditions. The following characteristics of gait performance were evaluated using different indices: variability, smoothness, regularity, complexity and local dynamic stability. An unpaired t-test was performed on the two groups for each method.
Results
Different indices followed the hypothesized trend in the two groups, even if differences were not always statistically significant: not growing adolescents showed a lower variability and complexity of gait and a higher smoothness/rhythm. Stability results showed a similarly stable gait pattern (or even higher in DT) in the growing adolescents when compared to their not growing peers.
Conclusions
The findings of the present work suggest that growth spurt affects gait variability, smoothness and regularity but not gait stability. It could be argued that sudden peripheral changes of the body affect the manifestation and the performance of gait, but, on the other hand, gait control is able to handle these modifications, maintaining the stability of the system.
This resource is the leading reference work designed to support and challenge those involved in developmental exercise science and medicine. This paediatric sub-specialty has become firmly established as a major component of sport and exercise medicine, which is reflected by a marked increase in research activity and publication. Experimental methods pioneered with adults have been successfully adapted for use with children and new non-invasive techniques have been developed and applied to paediatric research to provide new insights into understanding the exercising child.
There has recently been a growing interest in long-term athletic development for youth. Due to their unique physical, psychological and social differences, children and adolescents should engage in appropriately prescribed exercise programs that promote physical development to prevent injury and enhance fitness behaviours that can be retained later in life. Irrespective of whether a child is involved in organized sport or engages in recreational physical activity, there remains a need to adopt a structured, logical and evidence-based approach to the long-term development of athleticism. This is of particular importance considering the alarmingly high number of youth who fail to meet global physical activity recommendations and consequently present with negative health profiles. However, appropriate exercise prescription is also crucial for those young athletes that are physically underprepared and at risk of overuse injury due to high volumes of competition and an absence of preparatory conditioning. Whether the child accumulates insufficient or excessive amounts of exercise, or falls somewhere between these opposing ends of the spectrum, it is generally accepted that the young bodies of modern day youth are often ill-prepared to tolerate the rigors of sports or physical activity. All youth should engage in regular physical activity and thus should be viewed as 'athletes' and afforded the opportunity to enhance athleticism in an individualized, holistic and child-centred manner. Due to the emerging interest in long-term athletic development, an authorship team was tasked on behalf of the National Strength and Conditioning Association (NSCA) to critically synthesize existing literature and current practices within the field and to compose a relevant position statement. This document was subsequently reviewed and formally ratified by the NSCA Board of Directors. Figure 1 provides a list of the 10 pillars of successful long-term athletic development, which summarize the key recommendations detailed within the consensus statement. With these pillars in place, it is believed that the NSCA can (i) help foster a more unified and holistic approach to youth physical development, (ii) promote the benefits of a lifetime of healthy physical activity, and (iii) prevent and/or minimize injuries from sports participation for all boys and girls. Copyright (C) 2016 by the National Strength & Conditioning Association.
Physical changes associated with puberty may conflict with functional and aesthetic ideals for a career in ballet. The dance teacher is in a position to guide young dancers through the pubertal transition, although dancers rather than teachers are often the focus of research. This study explores the social stimulus value of the female body in ballet as perceived by the dance teacher and how value may change during puberty. Ten UK dance teachers were interviewed; interpretative phenomenological analysis was used. Four main themes perceived by dance teachers emerged as central to the social stimulus value of the body among adolescent dancers: the ideal body; teacher approaches to managing puberty in the dance environment; puberty as a ‘make or break’ stage in ballet; and teacher awareness of pubertal onset and the implications of timing. Dance teachers can play an important role in moderating external and individual expectations during the pubertal transition.
This study assessed the relative age effect (RAE) in judo athletes who participated in the Olympic Games from 1964 to 2012. The names and birth-dates of the Olympic judo athletes were collected from open-access websites. Data from male (n = 1,762) and female (n = 665) competitors were analyzed separately. Chi-squared tests were performed to investigate REA in medalists, and by weight categories and sexes. When the analyses used semesters to divide the period when the athletes were born, a RAE was found in male heavyweight athletes and male medallists. Thus, in a selected group of judo athletes who had participated at the highest competitive level, RAEs were present in both athletes who won Olympic medals and heavyweight athletes in the male group.
The aim of the study was to investigate whether an increased risk of injury occurrence can be determined through frequent anthropometric measurements in elite-standard youth soccer players. Over the course of one season, we followed 101 male elite-standard youth soccer players between 11 and 19 years of age. Height and body mass were monitored at monthly measurement intervals and fat percentage was assessed every 3 months by use of the sum of skinfold method. Growth in height (cm), alternations in body mass index (kg/m(2)), fat percentage and fat-free mass index (kg/m(2)) were calculated. Injuries were recorded in accordance with the recommendations of the FIFA Consensus Model for Injury Registration. Odds ratio scores and 95% confidence intervals were calculated using binary logistic regression analyses. The following anthropometric injury risk factors were identified: ≥ 0.6 centimeter growth per month (p=0.03; OR=1.63; 95% CI: 1.06-2.52), ≥ 0.3 kg/m(2) increase of body mass index value per month (p=0.03; OR=1.61; 95% CI: 1.04-2.49) and low fat percentage; i. e., < 7% for players aged 11-16 and < 5% for players over 16 years (p=0.01; OR=1.81; 95% CI: 1.18-2.76). Individual monitoring of anthropometrics provides useful information to determine increased risk of injury occurrence in elite-standard youth soccer.
© Georg Thieme Verlag KG Stuttgart · New York.
The search for talent is pervasive in youth sports. Selection/exclusion in many sports follows a maturity-related gradient largely during the interval of puberty and growth spurt. As such, there is emphasis on methods for assessing maturation. Commonly used methods for assessing status (skeletal age, secondary sex characteristics) and estimating timing (ages at peak height velocity (PHV) and menarche) in youth athletes and two relatively recent anthropometric (non-invasive) methods (status-percentage of predicted near adult height attained at observation, timing-predicted maturity offset/age at PHV) are described and evaluated. The latter methods need further validation with athletes. Currently available data on the maturity status and timing of youth athletes are subsequently summarised. Selection for sport and potential maturity-related correlates are then discussed in the context of talent development and associated models. Talent development from novice to elite is superimposed on a constantly changing base-the processes of physical growth, biological maturation and behavioural development, which occur simultaneously and interact with each other. The processes which are highly individualised also interact with the demands of a sport per se and with involved adults (coaches, trainers, administrators, parents/guardians).
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The purpose of this study was to identify differences in traumatic and overuse injury incidence between talented soccer players who differ in the timing of their adolescent growth spurt. 26 soccer players (mean age 11.9 ± 0.84 years) were followed longitudinally for 3 years around Peak Height Velocity, calculated according to the Maturity Offset Protocol. The group was divided into an earlier and later maturing group by median split. Injuries were registered following the FIFA consensus statement. Mann-Whitney tests showed that later maturing players had a significantly higher overuse injury incidence than their earlier maturing counterparts both in the year before Peak Height Velocity (3.53 vs.0.49 overuse injuries/1 000 h of exposure,U = 49.50, z = − 2.049, p < 0.05) and the year of Peak Height Velocity (3.97 vs. 1.56 overuse injuries/1 000 h of exposure, U = 50.5, z = − 1.796,p < 0.05). Trainers and coaches should be careful with the training and match load they put on talented soccer players, especially those physically not (yet) able to handle that load. Players appear to be especially susceptible to injury between 13.5 and 14.5 years of age. Training and match load should be structured relative to maturity such that athletic development is maximized and the risk of injury is minimized.
Assessing biological maturity in studies of children is challenging. Sex-specific regression equations developed using anthropometric measures are widely used to predict somatic maturity. However, prediction accuracy was not established in external samples. Thus, we aimed to evaluate the fit of these equations, assess for over-fitting (adjusting as necessary), and calibrate using external samples.
We evaluated potential over-fitting using the original Pediatric Bone Mineral Accrual Study (PBMAS; 79 boys, 72 girls; 7.5-17.5 years). We assessed change in R and standard error of the estimate (SEE) with the addition of predictor variables. We determined the effect of within-subject correlation using cluster-robust variance and 5-fold random-splitting followed by forward-stepwise regression. We used dominant predictors from these splits to assess predictive abilities of various models. We calibrated using participants from the Healthy Bones Study-III (HBS-III; 42 boys, 39 girls; 8.9-18.9 years) and Harpenden Growth Study (HGS; 38 boys, 32 girls; 6.5-19.1years).
Change in R and SEE was negligible when later predictors were added during step-by-step refitting of the original equations, suggesting over-fitting. After redevelopment, new models included age*sitting height for boys (R=0.91; SEE=0.51) and age*height for girls (R=0.90; SEE=0.52). These models calibrated well in external samples; HBS boys: b0=0.04(0.05); b1=0.98(0.03); RMSE=0.89, HBS girls: b0=0.35(0.04); b1=1.01(0.02); RMSE=0.65, HGS boys: b0=-0.20(0.02); b1=1.02(0.01); RMSE=0.85, HGS girls: b0=-0.02(0.03); b1=0.97(0.02); RMSE=0.70; where b0=calibration intercept (standard error; SE) and b1=calibration slope (SE), and RMSE=root mean squared error (of prediction). We subsequently developed an age*height alternate for boys; allowing for predictions without sitting height.
Our equations provided good fits in external samples and provide an alternative to commonly used models. Original prediction equations were simplified with no meaningful increase in estimation error.
The process of maturation is continuous throughout childhood and adoles-cence. In a biological context, the effects of a child's maturation might mask or be greater than the effects associated with exposure to exercise. Pediatric exercise scientists must therefore include an assessment of biological age in study designs so that the confounding effects of maturation can be controlled for. In order to understand how maturation can be assessed, it is important to appreciate that 1 year of chronological time is not equivalent to 1 year of biological time. Sex-and age-associated variations in the timing and tempo of biological maturation have long been recognized. This paper reviews some of the possible biological maturity indicators that the pediatric exercise scientist can use. As a result, we recommend that any of the methods discussed could be used for gender-specific comparisons. Gender-comparison studies should either use skeletal age or some form of somatic index.
Adolescence refers to the period of physical and psychological development between childhood and adulthood. The beginning of adolescence is loosely anchored to the onset of puberty, which brings dramatic alterations in hormone levels and a number of consequent physical changes. Puberty onset is also associated with profound changes in drives, motivations, psychology, and social life; these changes continue throughout adolescence. There is an increasing number of neuroimaging studies looking at the development of the brain, both structurally and functionally, during adolescence. Almost all of these studies have defined development by chronological age, which shows a strong—but not unitary—correlation with pubertal stage. Very few neuroimaging studies have associated brain development with pubertal stage, and yet there is tentative evidence to suggest that puberty might play an important role in some aspects of brain and cognitive development. In this paper we describe this research, and we suggest that, in the future, developmental neuroimaging studies of adolescence should consider the role of puberty. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Objectives
With adolescent sport increasingly challenged by mismatches in size, new strategies are important to maximize participation. The objectives were to (1) improve the understanding of mismatches in physical size, speed and power in adolescent rugby union players, (2) explore associations between size and performance with demographic, playing-history, and injury profiles, and (3) explore the applicability of existing criteria for age/body mass-based dispensation (playing-down) strategies.
Methods
Using cross-sectional design, 485 male community rugby union players were recruited from three Australian states selected to represent community-based U12, U13, U14 and U15 players. Body mass, stature, speed (10, 30, and 40 metre sprints) and lower-leg power (relative peak power and relative peak force) were measured. Independent student t-tests, linear regressions and Chi square analyses were undertaken.
Results
Mean values in age groups for size, speed and power masked considerable overlap in the ranges within specific age groups of adolescent rugby players. Only a small proportion of players (approximately 5%) shared the highest and lowest tertiles for speed, relative peak power and body mass. Physical size was not related to injury. The mean body mass of current community rugby union players was above the 75th percentile on normative growth-charts.
Conclusion
The notion that bigger, faster, and more powerful characteristics occur simultaneously in adolescent rugby players was not supported in the present study. Current practices in body mass-based criteria for playing down an age group lack a sufficient evidence for decision-making. Dispensation solely based on body mass may not address mismatch in junior rugby union.
Biological maturation is associated with significant change to a number of physiological and structural processes throughout childhood and, in particular, adolescence. Mismatched rapid growth in the long bones relative to muscular lengthening may disrupt structure, neuromuscular function, and physical performance. Practitioners who work with school-age youth should be aware of the age-related changes that typically take place during a child's development to ensure that their strength and conditioning programming is as safe and effective as possible for enhancing performance and reducing injury risk. While there are several methods available to assess biological maturation, practitioners who work with youth can benefit from assessment methods that are available and feasible, and that provide utility in the quantification of the degree and stages of biological maturation that affect motor performance in children and adolescents. This manuscript synthesizes the relevant assessment methods, and provides a rationale for understanding usable biological maturation assessment tools that can aid in the development of training program design for youth.
Youth sport participation offers many benefits including the development of self-esteem, peer socialisation and general fitness. However, an emphasis on competitive success, often driven by goals of elite-level travel team selection, collegiate scholarships, Olympic and National team membership and even professional contracts, has seemingly become widespread. This has resulted in an increased pressure to begin high-intensity training at young ages. Such an excessive focus on early intensive training and competition at young ages rather than skill development can lead to overuse injury and burnout.
The relative age effect associated with cut-off dates for hockey eligibility has been an ongoing debate in certain academic circles and in the popular media. The effect is primarily found in Canadian Major Junior Hockey, where a disproportionate share of birthdays fall in the first three months of the year. But when the National Hockey League rosters of Canadian-born players are examined, the pattern is less pronounced. Using publically available data of hockey players from 2000–2009, we find that the relative age effect, as described by Nolan and Howell (2010) and Gladwell (2008), is moderate for the average Canadian National Hockey League player and reverses when examining the most elite professional players (i.e. All-Star and Olympic Team rosters). We also find that the average career duration is longer for players born later in the year. In sum, there is a surprising ‘relative age effect reversal’ that occurs from the junior leagues to the most elite level of hockey play. This supports an ‘underdog’ hypothesis, where the relatively younger players are thought to benefit by more competitive play with their older counterparts.
Abstract This study attempted to validate an anthropometric equation for predicting age at peak height velocity (APHV) in 193 Polish boys followed longitudinally 8-18 years (1961-1972). Actual APHV was derived with Preece-Baines Model 1. Predicted APHV was estimated at each observation using chronological age (CA), stature, mass, sitting height and estimated leg length. Mean predicted APHV increased from 8 to 18 years. Actual APHV was underestimated at younger ages and overestimated at older ages. Mean differences between predicted and actual APHV were reasonably stable between 13 and 15 years. Predicted APHV underestimated actual APHV 3 years before, was almost identical with actual age 2 years before, and then overestimated actual age through 3 years after PHV. Predicted APHV did not differ among boys of contrasting maturity status 8-11 years, but diverged among groups 12-15 years. In conclusion, predicted APHV is influenced by CA and by early and late timing of actual PHV. Predicted APHV has applicability among average maturing boys 12-16 years in contrast to late and early maturing boys. Dependence upon age and individual differences in actual APHV limits utility of predicted APHV in research with male youth athletes and in talent programmes.
The paper addresses the extraction and empirical testing of the hard core of assumptions underlying the construction principles of the German supportive system in youth elite sport. The support system turns out to be based on a mainly input-oriented concept. Invested sport-related time is regarded as a critical input variable and extensive and intensive time economy is systematically aimed at. Among 1,558 national squad athletes in all Olympic sports those with international and with national success at each junior age and elite age are compared regarding their former juvenile success and volume of training and participation in support programs. Effects of juvenile training- and support-related variables vary over time and in some cases turn into the opposite on the long hand. Juvenile success, the training volume in the individual’s current main sport, and the inclusion in support programs have no significant or negative effects on long-term success in elite sport. In contrast, international elite athletes are characterized by a higher juvenile training volume only in other disciplines beyond the individual’s current main sport and correspondingly by a decelerated juvenile training-, competition-, and support-related development in their main sport. Results are discussed by integrating social-science, training-science, economic, and educational perspectives.
Keywords: evaluation – elite sport – sport organisations – training
At any given age, there is wide variation among children in size, physique and body composition, rate of growth, and timing and tempo of biologic maturation.
There is corresponding variation among young female athletes. Successful young female athletes are a highly selected group in terms of skill, size and physique, and often socioeconomic status. Comparisons of young female athletes with reference data for the general population indicate that, in general, these young females grow and mature in a similar manner as non-athletes with variation among sports. The short stature and decreased body mass observed in some élite young female athletes likely reflects the selection practice of specific sports. In some of these élite sports there may be a focus on desirable physical and maturational characteristics. It is difficult to attribute the observed variation in the growth and maturation of young athletes to the effects of systematic training. The data presently available do not meet the criteria for causality, and many factors known to influence growth and maturation are usually not considered in studies of young athletes.
A model for adolescent involvement in physical activity (PA) that incorporates individual differences in biological maturation is presented. The biocultural model of maturity-associated variance in physical activity recognizes PA as a complex and multifaceted behaviour that exists in multiple contexts (e.g., transport, vocation, sport, exercise) and can be viewed from multiple perspectives (e.g., energy expenditure, movement counts, performance outcomes, fitness). The model holds that biological maturation can exert both direct and indirect effects on PA during adolescence. Direct effects imply a direct and unmediated effect of individual differences in maturation on PA. Indirect effects imply influences of individual differences in maturation on PA that are mediated by psychological constructs (e.g., self-perceptions, beliefs) and/or are moderated by exogenous factors (e.g., social interaction, culture) associated with pubertal maturation.
This study tested a mediated effects model of psychological and behavioral adaptation to puberty within the context of physical activity (PA).
Biological maturity status, physical self-concept, PA, and health-related quality of life (HRQoL) were assessed in 222 female British year 7 to 9 pupils (mean age = 12.7 years, SD = .8).
Structural equation modeling using maximum likelihood estimation and bootstrapping procedures supported the hypothesized model. Maturation status was inversely related to perceptions of sport competence, body attractiveness, and physical condition; and indirectly and inversely related to physical self-worth, PA, and HRQoL. Examination of the bootstrap-generated bias-corrected confidence intervals representing the direct and indirect paths between suggested that physical self-concept partially mediated the relations between maturity status and PA, and maturity status and HRQoL.
Evidence supports the contention that perceptions of the physical self partially mediate relations maturity, PA, and HRQoL in adolescent females.
Sex-specific equations for predicting maturity offset, time before or after peak height velocity (PHV), were evaluated in 63 girls and 74 boys from the Fels Longitudinal Study. Serially measured heights (0.1 cm), sitting heights (0.1 cm), weights (0.1 kg), and estimated leg lengths (0.1 cm) from 8 to 18 years were used. Predicted age at PHV (years) was calculated as the difference between chronological age (CA) and maturity offset. Actual age at PHV for each child was derived with a triple logistic model (Bock-Thissen-du Toit). Mean predicted maturity offset was negative and lowest at 8 years and increased linearly with increasing CA. Predicted ages at PHV increased linearly with CA from 8-18 years in girls and from 8-13 years in boys; predictions varied within relatively narrow limits from 12-15 years and then increased to 18 years in boys. Differences between predicted and actual ages at PHV among youth of contrasting maturity status were significant across the age range in both sexes. Dependence of predicted age at PHV upon CA at prediction and on actual age at PHV limits its utility as an indicator of maturity timing and in sport talent programs.
YOUNG ATHLETES PARTICIPATING IN HIGH-INTENSITY SPORT DISPLAY AN INHERENT RISK OF SPORTS-RELATED INJURY, AND THIS IS HEIGHTENED AT VARIOUS STAGES OF GROWTH AND MATURATION. RECENT TRENDS HAVE HIGHLIGHTED A RANGE OF INJURY RISK FACTORS AND THE IMPORTANCE OF INJURY PREVENTION STRATEGIES WITHIN FEMALE SOCCER PLAYERS. HOWEVER, THERE IS A PAUCITY OF INFORMATION PERTAINING TO MALE YOUTH PLAYERS. THIS ARTICLE PROVIDES AN OVERVIEW OF THE AVAILABLE LITERATURE AND OUTLINES A RANGE OF RISK FACTORS THAT MAY INCREASE RELATIVE RISK OF INJURY IN MALE YOUTH SOCCER PLAYERS, INCLUDING GROWTH AND MATURATION, MOVEMENT SKILL, FATIGUE, AND PREVIOUS INJURY.
The objective of this study was to review the evidence for selected risk factors of lower extremity overuse injuries in young elite female ballet dancers. An electronic search of key databases from 1969 to July 2013 was conducted using the keywords dancers, ballet dancers, athletes, adolescent, adolescence, young, injury, injuries, risk, overuse, lower limb, lower extremity, lower extremities, growth, maturation, menarche, alignment, and biomechanics. Thirteen published studies were retained for review. Results indicated that there is a high incidence of lower extremity overuse injuries in the target population. Primary risk factors identified included maturation, growth, and poor lower extremity alignment. Strong evidence from well-designed studies indicates that young elite female ballet dancers suffer from delayed onset of growth, maturation, menarche, and menstrual irregularities. However, there is little evidence that this deficit increases the risk of overuse injury, with the exception of stress fractures. Similarly, there is minimal evidence linking poor lower extremity alignment to increased risk of overuse injury. It is concluded that further prospective, longitudinal studies are required to clarify the relationship between growth, maturation, menarche, and lower extremity alignment, and the risk of lower extremity overuse injury in young elite female ballet dancers.
The purpose of this chapter is to review the growth and development of the normal healthy child and discuss whether training can be attributed to potential effects on growth and maturation. Short stature and late maturation of youth artistic gymnasts are often attributed to the effects of intensive training from a young age. However, it is important to remember that at any given age, there is wide variation among children in size, physique and body composition, rate of growth, and timing and tempo of biological maturation. Successful young athletes are a highly selected group in terms of skill, size, and physique, and often socioeconomic status. Comparisons of young athletes with reference data for the general population indicate that, in general, these young athletes grow and mature in a similar manner as nonathletes, with variation among sports. The short stature and decreased body mass observed in some elite gymnasts likely reflects the selection practice of the sport. Especially in female gymnastics, where there is a focus on desirable physical and maturational characteristics. Although training in the most part starts at an early age, it is difficult to attribute the observed variation in the growth and maturation of young athletes to the effects of systematic training. This is because much of the currently available data does not meet the criteria for causality, and many factors known to influence growth and maturation are usually not considered in studies of young athletes.
Adolescence is a period of formative biological and social transition. Social cognitive processes involved in navigating an increasingly complex social world continue to develop throughout adolescence. Research in the past 15 years has demonstrated significant functional and structural changes in the brain during adolescence. Areas of the social brain undergo both structural changes and functional reorganization during the second decade of life, possibly reflecting a sensitive period for adapting to one's social environment. The changes in social environment that occur during adolescence might interact with increasing executive functions and heightened social sensitivity to influence a number of adolescent behaviours. I will discuss the importance of considering the social environment and social rewards in research on adolescent cognition and behaviour.
Serial data for 268 normal children (144 boys, 124 girls) have been used to calculate predicted adult statures without using skeletal age. Present statures at an age have been used with these predicted values to obtain ratios that are significantly correlated (p <.05 or < .01) with accepted measures of physical maturity from 5 to 15 years in boys, and from 3 to 13 years in girls. Reference values for this ratio are provided. It is recommended that this non-invasive method of measuring maturity be used when irradiation cannot be justified or when the invasion of personal privacy is inappropriate.
The X-ray films of the hands of 55 boys in the Little League World Series, 1957, were assessed for maturation (skeletal) age according to Todd's 1937 standards. There were four boys of chronological age 11:0–11:9, 42 of age 12:0–12:11, 9 of age 13:0–13:11. It was found that 16 boys (29%) were retarded, or maturation age less than chronological age; 39 boys (71%) were advanced, or maturation age more than chronological age. With correction of maturation age within ± one year of chronological age, the significant figures are five retarded, 25 advanced, for a total of 30. Of these 17 percent are retarded, 83 percent advanced. It is concluded that Little League ball players of championship caliber are, in general, biologically advanced. Such an advancement is deemed a positive factor in young boys indulging in competitive sports.
Objective
To identify growth, maturation and biomechanical risk factors for overuse injury in elite adolescent ballet dancers.
Methods
Maturation (Tanner scale), growth (foot length change) and age at onset of menarche were recorded in elite adolescent ballet dancers. A modified knee valgus angle and lateral tilt of the pelvis were measured using 2D video during two dance movements (fondu, temps levé) to quantify lower extremity alignment. Overuse dance injuries were recorded by a physiotherapist. The injury rate ratio (RR) associated with each variable was estimated using over-dispersed Poisson regression modelling.
Results
Changes in right foot length (RR = 1.41, CI = 0.93-2.13), right knee angles during the fondu (RR = 0.68, CI = 0.45-1.03) and temps levé (RR = 0.72, CI = 0.53-0.98), and pelvic angles during the temps levé on the left (RR = 0.52, CI = 0.30-0.90) and fondu on the right (RR = 1.28, CI = 0.91-1.80) were associated with substantial changes in injury risk.
Conclusions
Rate of growth in elite adolescent ballet dancers is likely associated with an increase in risk of lower extremity overuse injury and better right lower extremity alignment is likely associated with a reduction in risk of right lower extremity overuse injury.
Abstract This study examined the disturbing effects of relative age on the talent identification process in the talent development programme of the German Football Association. The bias in the selection rate was examined via the extent of relative age effects. The bias in motor performance diagnostics was analysed by comparing the motor performance of selected players with normal motor development. The mechanisms underlying the relative age biases in motor performance were examined by modelling the direct and indirect effects of relative age on single motor performance tests for sprint, running agility, dribbling and ball passing and control. Data from 10,130 selected football players from the U12 to U15 age groups were collected in autumn 2010. The birth distribution differed significantly from the reference population with approximately 61% of the players born in the first half of the year. The selection probability was approximately two times higher for players born in the first quarter of the year than for players born in the last quarter. Revised motor performance diagnostics showed better results on average for relatively younger players. Path analysis revealed significant direct and indirect relative age effects for physiologically demanding tests and almost no effects for technically demanding tests. Large sample sizes allowed high resolution in relative age with additional informational content and multivariate modelling of the complex relationships among relative age, physical development and motor performance. The results are discussed on how relative age affects the effectiveness and fairness of talent identification and development processes.
Abstract The aim of this study was to investigate whether weight categories prevent young athletes from being exposed to a relative age effect. The dates of birth of all French female (n = 727) and male (n = 5440) amateur boxers who participated in the 2010-2011 season were collected from the federation database. The dates of birth of all French male professional boxers (n = 354) were also collected. The results show an absence of a relative age effect among French female and male amateur boxers. The results also show an absence of this phenomenon among French male professional boxers. The male 18-18+ age category reveal an inverse relative age effect. This inverse relative age effect might be interpreted as the result of a strategic adaptation from relatively younger children who shift from one sport to another where there are weight categories in order to ensure fair competition. The results of this study suggest that the weight category system is a possible solution within the relative age effect phenomenon.
The relationship of fractures to physical activity and growth velocity in stature and metacarpal II bone dimensions was investigated in adolescent Belgian boys, Peak fracture incidence occurred between 12 and 14 yr of age and preceded the age at peak height velocity. The peak fracture rate occurred during mid adolescence (\pm 2 SD of the age at peak height velocity) and was twice as high as the rates before and after this period, The majority of fractures occurred during active participation in sports and general physical activities. The age at peak growth velocity for metacarpal cortical thickness, an indirect measure of bone mineral content, was about 6 months later than the ages at peak height velocity and peak growth velocity for metacarpal length. Peak fracture incidence occurred during a period when the amount of time spent in sports physical activity was low compared with later years. A lag in cortical bone thickness and mineralization, relative to linear skeletal growth, and unknown factors associated with active participation in sports, rather than an increase in the amount of physical activity, appear to be the predominant factors associated with the increased fracture incidence in Belgian boys during the growth spurt.
(C)1993The American College of Sports Medicine
Introduction Sport has high social valence and is a primary context for physical activity for the majority of youth. More-over, the number of youth competing in sports at na-tional and international levels continues to increase. As a consequence of emphasis on sport, many children and adolescents are encouraged to begin specialized, systematic training in a sport at relatively young ages with the goal of attaining elite status. Of course, it is not clear if it is the youngster's goal or that of his/her parents, coaches and/or sports system. Focus on elite young athletes, or young athletes as-piring for elite status, often detracts from the potential importance of organized sport in the lives of all chil-dren and adolescents. The highly talented are a very visible minority whereas the overwhelming majority of youth who participate and never attain elite levels pass under the radar. Unfortunately, attention and often resources, as well as commentaries in the print and electronic media, focus on the exceptional minority! The purpose of this review is twofold. First, it con-siders organized youth sport in the lives of children and adolescents who fill the rosters of programs through-out the world, i.e. the majority. It specifically addresses the following question: Do organized sport programs for youth meet their stated objectives? Second, it con-siders sport programs for elite, the select, highly visible minority, in terms of the rush to early specialization and potential consequences of being labeled talented at a young age.
ObjectivesTo investigate relations among body size, perceptions of coaching behaviors, and attitudes toward the coach and sport in adolescent female athletes in three sports.DesignField correlational design.MethodFemale athletes, 14–18 years, participating in high school basketball, gymnastics, and soccer (N=227) completed questionnaires dealing with the perceived frequency of coaching behaviors, evaluative reactions to the coach, and liking for the sport. Coaches rated the ability and performance of each athlete during the season.ResultsPartial correlations between indicators of body size and athlete perceptions of coaching behaviors, controlling for age and ratings of ability and performance, varied by sport. Among gymnasts, measures of body size were associated with less positive and supportive interactions with coaches and less liking for the coach. Contrary to expectations, the stature of the basketball players was unrelated to their perceptions of coaching behaviors or their liking for the coach and sport. Body size was unrelated to athlete perceptions of coaching behaviors and evaluative responses in soccer.ConclusionsIn support of [Petersen, A. C., & Taylor, B. (1980). The biological approach to adolescence: Biological change and psychological adaptation. In J. Adelson (Ed.), Handbook of adolescent psychology (pp. 117–155). New York: Wiley–Interscience.] Mediated Effects Model of Psychological Adaptation to Puberty, the results suggest that body size, even with age, ability and performance held constant, may engage sport specific stereotypes that influence coaches' positive and negative behaviors, particularly in sports where body size is related to athletic potential.
The brain has evolved to understand and interact with other people. We are increasingly learning more about the neurophysiological basis of social cognition and what is known as the social brain, that is the network of brain regions involved in understanding others. This paper focuses on how the social brain develops during adolescence. Adolescence is a time characterized by change - hormonally, physically, psychologically and socially. Yet until recently this period of life was neglected by cognitive neuroscience. In the past decade, research has shown that the brain develops both structurally and functionally during adolescence. Large-scale structural MRI studies have demonstrated development during adolescence in white matter and grey matter volumes in regions within the social brain. Activity in some of these regions, as measured using fMRI, also shows changes between adolescence and adulthood during social cognition tasks. I will also present evidence that theory of mind usage is still developing late in adolescence. Finally, I will speculate on potential implications of this research for society.