Movement demands of elite rugby league players during Australian National Rugby League and European Super League matches

This is the authors' PDF version as accepted for publication of an article published in International Journal of Sports Physiology and Performance© 2014. The definitive version is available at http://journals.humankinetics.com/ijsppThis study compared the movement demands of players competing in matches from the elite Australian and European rugby league competitions

High chronic training loads and exposure to bouts of maximal velocity running reduce injury risk in elite Gaelic football.

OBJECTIVES: To examine the relationship between chronic training loads, number of exposures to maximal velocity, the distance covered at maximal velocity, percentage of maximal velocity in training and match-play and subsequent injury risk in elite Gaelic footballers. DESIGN: Prospective cohort design. METHODS: Thirty-seven elite Gaelic footballers from one elite squad were involved in a one-season study. Training and game loads (session-RPE multiplied by duration in min) were recorded in conjunction with external match and training loads (using global positioning system technology) to measure the distance covered at maximal velocity, relative maximal velocity and the number of player exposures to maximal velocity across weekly periods during the season. Lower limb injuries were also recorded. Training load and GPS data were modelled against injury data using logistic regression. Odds ratios (OR) were calculated based on chronic training load status, relative maximal velocity and number of exposures to maximal velocity with these reported against the lowest reference group for these variables. RESULTS: Players who produced over 95% maximal velocity on at least one occasion within training environments had lower risk of injury compared to the reference group of 85% maximal velocity on at least one occasion (OR: 0.12, p=0.001). Higher chronic training loads (≥4750AU) allowed players to tolerate increased distances (between 90 to 120m) and exposures to maximal velocity (between 10 to 15 exposures), with these exposures having a protective effect compared to lower exposures (OR: 0.22 p=0.026) and distance (OR=0.23, p=0.055). CONCLUSIONS: Players who had higher chronic training loads (≥4750AU) tolerated increased distances and exposures to maximal velocity when compared to players exposed to low chronic training loads (≤4750AU). Under- and over-exposure of players to maximal velocity events (represented by a U-shaped curve) increased the risk of injury

Anthropometric and Physical Qualities of Elite Male Youth Rugby League Players

Rugby league is a collision team sport played at junior and senior levels worldwide, whereby players require highly developed anthropometric and physical qualities (i.e., speed, change of direction speed, aerobic capacity, muscular strength and power). Within junior levels, professional clubs and national governing bodies implement talent identification and development programmes to support the development of youth (i.e., 13-20 years) rugby league players into professional athletes. This review presents and critically appraises the anthropometric and physical qualities of elite male youth rugby league players aged between 13 and 20 years by age category, playing standard and playing position. Height, body mass, body composition, linear speed, change of direction speed, aerobic capacity, muscular strength and power characteristics are presented and demonstrate that qualities develop with age and differentiate between playing standard and playing position. This highlights the importance of anthropometric and physical qualities for the identification and development of youth rugby league players. However, factors such as maturity status, variability in development, longitudinal monitoring and career attainment should be considered to help understand, identify and develop the physical qualities of youth players. Further extensive research is required into the anthropometric and physical qualities of youth rugby league players, specifically considering national standardized testing batteries, links between physical qualities and match performance, together with intervention studies, to inform the physical development of youth rugby league players for talent identification and development purposes

Aerobic Fitness and Playing Experience Protect Against Spikes in Workload: The Role of the Acute:Chronic Workload Ratio on Injury Risk in Elite Gaelic Football.

PURPOSE: To examine the association between combined session-RPE workload measures and injury risk in elite Gaelic footballers. METHODS: Thirty-seven elite Gaelic footballers (mean ± SD age of 24.2 ± 2.9 yr) from one elite squad were involved in a single season study. Weekly workload (session-RPE multiplied by duration) and all time-loss injuries (including subsequent week injuries) were recorded during the period. Rolling weekly sums and week-to-week changes in workload were measured, allowing for the calculation of the 'acute:chronic workload ratio' that was calculated by dividing acute workload (i.e. 1-week workload) by chronic workload (i.e. rolling average 4-weekly workload). Workload measures were then modelled against all injury data sustained using a logistic regression model. Odds ratios (OR) were reported against a reference group. RESULTS: High 1-weekly workloads (≥2770 AU, OR = 1.63 - 6.75) were associated with significantly higher risk of injury compared to a low training load reference group (1.5), players with 1 year experience had a higher risk of injury (OR = 2.22) and players with 2-3 (OR = 0.20) and 4-6 years (OR = 0.24) of experience had a lower risk of injury. Players with poorer aerobic fitness (estimated from a 1 km time trial) had a higher injury risk compared to players with higher aerobic fitness (OR = 1.50-2.50). An acute:chronic workload ratio of (≥2.0) demonstrated the greatest risk of injury. CONCLUSIONS: These findings highlight an increased risk of injury for elite Gaelic football players with high (>2.0) acute:chronic workload ratios and high weekly workloads. A high aerobic capacity and playing experience appears to offer injury protection against rapid changes in workload and high acute:chronic workload ratios. Moderate workloads, coupled with moderate-high changes in the acute:chronic workload ratio appear to be protective for Gaelic football players

Can the workload–injury relationship be moderated by improved strength, speed and repeated-sprint qualities?

Objectives The aim of this study was to investigate potential moderators (i.e. lower body strength, repeated-sprint ability [RSA] and maximal velocity) of injury risk within a team-sport cohort. Design Observational Cohort Study. Methods Forty male amateur hurling players (age: 26.2 ± 4.4 yr, height: 184.2 ± 7.1 cm, mass: 82.6 ± 4.7 kg) were recruited. During a two-year period, workload (session RPE x duration), injury and physical qualities were assessed. Specific physical qualities assessed were a three-repetition maximum Trapbar deadlift, 6 × 35-m repeated-sprint (RSA) and 5-, 10- and 20-m sprint time. All derived workload and physical quality measures were modelled against injury data using regression analysis. Odds ratios (OR) were reported against a reference group. Results Moderate weekly loads between ≥ 1400 AU and ≤ 1900 AU were protective against injury during both the pre-season (OR: 0.44, 95%CI: 0.18–0.66) and in-season periods (OR: 0.59, 95% CI: 0.37–0.82) compared to a low load reference group (≤ 1200 AU). When strength was considered as a moderator of injury risk, stronger athletes were better able to tolerate the given workload at a reduced risk. Stronger athletes were also better able to tolerate larger week-to-week changes ( > 550 AU to 1000 AU) in workload than weaker athletes (OR = 2.54–4.52). Athletes who were slower over 5-m (OR: 3.11, 95% CI: 2.33–3.87), 10-m (OR: 3.45, 95% CI: 2.11–4.13) and 20-m (OR: 3.12, 95% CI: 2.11–4.13) were at increased risk of injury compared to faster athletes. When repeated-sprint total time (RSAt) was considered as a moderator of injury risk at a given workload (≥ 1750 AU), athletes with better RSAt were at reduced risk compared to those with poor RSAt (OR: 5.55, 95%: 3.98–7.94). Conclusions These findings demonstrate that well-developed lower-body strength, RSA and speed are associated with better tolerance to higher workloads and reduced risk of injury in team-sport athletes

Positional group significantly influences the offensive and defensive skill involvements of junior representative rugby league players during match play

© 2015 Taylor & Francis. This study examined the skill involvements of three positional groups across a junior representative rugby league season. Data were collected from 45 rugby league players (mean ± SD; age = 16.5 ± 1.0 years) currently participating in the Harold Matthews and SG Ball Cup. Players were subdivided into hit-up forwards, adjustables and outside backs. The frequency (n · min−1) of offensive, defensive and overall involvements was coded for each group using a notation system and a practical coach skill analysis tool. Multivariate analysis of variance (MANOVA) revealed a significant effect of playing position on skill involvements (F = 9.06; P < 0.001; ES = 0.41). Hit-up forwards performed a significantly greater frequency of offensive (0.31 ± 0.10), defensive (0.42 ± 0.15) and overall involvements (0.74 ± 0.19) when compared to adjustables (0.20 ± 0.08, 0.28 ± 0.08 and 0.52 ± 0.15, respectively) and outside backs (0.20 ± 0.12, 0.11 ± 0.07 and ± 0.31 ± 0.17, respectively). Further, adjustables performed a significantly greater number of defensive (0.28 ± 0.08) and overall involvements (0.52 ± 0.15) when compared to outside backs (0.11 ± 0.07 and 0.31 ± 0.17, respectively). The findings of this study suggest that it is important to consider a junior player’s positional group when analysing their skill involvements. Information gained from this study could assist in the design of specific training methodologies for junior rugby league players in high-level talent development programmes

Training Practices of Academy Rugby League and their alignment to Physical Qualities deemed important for Current and Future Performance

This study aimed to investigate rugby league coaches’ perceptions of physical qualities for current and future performance, while also establishing the training practices of Under-16 and Under-19 players. Twenty-four practitioners (rugby coach, strength and conditioning coach) working within nine Super League clubs completed a questionnaire. The questionnaire required practitioners to rank eleven physical qualities (i.e., strength, power, acceleration, maximum speed, aerobic endurance, change of direction, agility, height, body mass, lean mass and fat mass) by importance for current performance, future performance and career longevity according to playing position (forwards, backs, hookers & halves). Practitioners were asked to provide detail on the frequency and duration of each type of training session completed during a typical week throughout each phase of the season; pre-season, in-season (early), in-season (mid), and in-season (late). Typically, practitioners ranked strength, power and acceleration qualities highest, and endurance and anthropometric qualities lowest. The importance of physical qualities varied according to each playing level and position. Training practices of U16 and U19 players differed during each phase of the season, with U19 players undertaking greater training volumes than U16s players. Overall, the physical qualities coaches perceived as most important were not reflected within their training practices. Rugby league practitioners can use this information as a reference source to design long term athletic development plans, prescribe training and during player development procedures. Moreover, these data can inform and improve training practices while influencing the design of pre-season preparatory phases and in-season periods

Top secret training data? External training loads of a cup winning English Super League rugby league team

This study quantified the field-based external training loads of professional rugby league players using global positioning systems technology across a playing season. Eleven professional rugby league players were monitored during all field-based training activities during the 2014 Super League season. Training sessions undertaken in preseason (n = 211 observations), early (n = 194 observations), middle (n = 171 observations) and late (n = 206 observations) phases of the in-season were averaged for each player and used in the analyses. Large reductions in external training loads between preseason and in-season periods were observed. Within season, a decrease in intensity (relative distance, absolute and relative total-HSR) with a limited change in training duration was observed. These data provide a useful reference for coaches working with similar cohorts, while future research should quantify the adequacy of the training loads reported, considering impact on performance and injury