Sullivan, C, Kempton, T, Ward, P & Coutts, AJ 2020, 'The efficacy of talent selection criteria in the Australian Football League.', Journal of sports sciences, vol. 38, no. 7, pp. 773-779.View/Download from: Publisher's site
This study investigated the association between talent selection criteria, draft order and match performance in professional Australian Football players. Physical performance results from the Australian Football League (AFL) National Draft combine and non-performance based talent selection criteria were collated for all players drafted in the National Draft with selections 1-80 between 2003 and 2008 (n = 318). Match performance was assessed via the AFL Player Ranking metric that was provided by a commercial statistical provider (Champion Data Pty Ltd). A combination of stepwise multiple regression and linear mixed model analyses examined the influence of National Draft combine physical performance assessments and non-performance based talent selection criteria on draft order and future match performance. Earlier draft selection was associated with Under-18 all Australian team selection, height, Under-18 National Championship participation and indigenous status. The 20 m sprint and state of origin were associated with later draft selection. Under-18 all Australian team selection increased both Player Ranking/game and total Player Ranking. Under-18 all Australian team selection displays efficacy for selecting players with the potential for success.
Ryan, S, Kempton, T, Impellizzeri, FM & Coutts, AJ 2020, 'Training monitoring in professional Australian football: theoretical basis and recommendations for coaches and scientists', Science and Medicine in Football, vol. 4, no. 1, pp. 52-58.View/Download from: Publisher's site
© 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group. Australian football (AF) is a high-intensity field-based sport with regular collisions and intense physical demands such as jumping, tackling and jostling, resulting in neuromuscular fatigue and soreness, combined with external stressors (i.e., sponsorship, education, family). These can influence an athlete's fatigue and recovery status, requiring an individualised approach to monitoring to optimise training readiness. Optimal readiness would reflect a condition where an athlete has no impairment of physical performance, no mental fatigue or excessive psychological distress. A theoretical framework exists for athlete monitoring that includes the quantification of training load and understanding individual ability to tolerate the training demands imposed by coaches. However, while this approach is thought to ultimately determine the readiness of a player for training and competition, it has not been tested empirically. The purpose of this review is to describe the theoretical basis that underpins athlete monitoring systems, and to provide an overview of their contribution to decision-making processes in planning and delivery of training in professional AF players. This review can assist coaches and scientists to gain a better understanding of commonly used monitoring measures and how the information derived from these sources is applied in a professional AF environment.
Ward, P, Windt, J & Kempton, T 2019, 'Business Intelligence: How Sport Scientists Can Support Organization Decision Making in Professional Sport.', International journal of sports physiology and performance, vol. 14, no. 4, pp. 544-546.View/Download from: Publisher's site
The application of scientific principles to inform practice has become increasingly common in professional sports, with increasing numbers of sport scientists operating in this area. The authors believe that in addition to domain-specific expertise, effective sport scientists working in professional sport should be able to develop systematic analysis frameworks to enhance performance in their organization. Although statistical analysis is critical to this process, it depends on proper data collection, integration, and storage. The purpose of this commentary is to discuss the opportunity for sport-science professionals to contribute beyond their domain-specific expertise and apply these principles in a business-intelligence function to support decision makers across the organization. The decision-support model aims to improve both the efficiency and the effectiveness of decisions and comprises 3 areas: data collection and organization, analytic models to drive insight, and interface and communication of information. In addition to developing frameworks for managing data systems, the authors suggest that sport scientists' grounding in scientific thinking and statistics positions them to assist in the development of robust decision-making processes across the organization. Furthermore, sport scientists can audit the outcomes of decisions made by the organization. By tracking outcomes, a feedback loop can be established to identify the types of decisions that are being made well and the situations where poor decisions persist. The authors have proposed that sport scientists can contribute to the broader success of professional sporting organizations by promoting decision-support services that incorporate data collection, analysis, and communication.
Ryan, S, Kempton, T, Pacecca, E & Coutts, AJ 2019, 'Measurement Properties of an Adductor Strength Assessment System in Professional Australian Footballers.', International Journal of Sports Physiology and Performance, vol. 14, no. 2, pp. 256-259.View/Download from: Publisher's site
To examine the measurement properties of an adductor strength assessment system in professional Australian footballers.Observational, longitudinal design. Test-retest reliability data were collected from 18 professional Australian footballers from one club on the same day during the 2017 AFL competition. Week-to-week variation data were collected on 45 professional Australian footballers from one club during the same season at 48, 72 and 120 h post-match (rounds 1-23). Players lay beneath a GroinBar Hip Strength Testing System in supine position with their knee joint at an angle of 60 degrees. Force (N) was extracted for left and right limbs of each player and a pain score from 0-10 (0=no pain, 10=maximum pain) was provided. Coefficient of variation (CV) and smallest worthwhile change (SWC) were calculated on test-retest data. Signal-to-noise ratio (SNR) was calculated for each major time point. Mean difference between force scores in a subgroup of players with and without groin pain (n=18) were collected as evidence of construct validity for the system.Test CV was 6.3% [4.9, 9.0]. CV exceeded the SWC on both limbs. Intraclass coefficient (ICC) was 0.94. SNR ranged from 1.6 and 2.6 on average for 48, 72 and 120 h post-match. Groin pain had a very likely moderate negative effect on adductor strength (ES: 0.41).The system possesses greater measurement precision to dynamometry and sphygmomanometer adductor strength assessment methods in professional Australian footballers. Increased groin pain reduced groin squeeze force production. Practitioners may interpret changes exceeding 6.3% in adductor strength as real.
Ryan, S, Pacecca, E, Tebble, J, Hocking, J, Kempton, T & Coutts, AJ 2019, 'Measurement Characteristics of Athlete Monitoring Tools in Professional Australian Football.', International journal of sports physiology and performance, vol. 15, no. 4, pp. 457-463.View/Download from: Publisher's site
PURPOSE:To examine the measurement reliability and sensitivity of common athlete monitoring tools in professional Australian Football players. METHODS:Test-retest reliability (noise) and weekly variation (signal) data were collected from 42 professional Australian footballers from 1 club during a competition season. Perceptual wellness was measured via questionnaires completed before main training sessions (48, 72, and 96 h postmatch), with players providing a rating (1-5 Likert scale) regarding their muscle soreness, sleep quality, fatigue level, stress, and motivation. Eccentric hamstring force and countermovement jumps were assessed via proprietary systems once per week. Heart rate recovery was assessed via a standard submaximal run test on a grass-covered field with players wearing a heart rate monitor. The heart rate recovery was calculated by subtracting average heart rate during final 10 seconds of rest from average heart rate during final 30 seconds of exercise. Typical test error was reported as coefficient of variation percentage (CV%) and intraclass coefficients. Sensitivity was calculated by dividing weekly CV% by test CV% to produce a signal to noise ratio. RESULTS:All measures displayed acceptable sensitivity. Signal to noise ratio ranged from 1.3 to 11.1. Intraclass coefficients ranged from .30 to .97 for all measures. CONCLUSIONS:The heart rate recovery test, countermovement jump test, eccentric hamstring force test, and perceptual wellness all possess acceptable measurement sensitivity. Signal to noise ratio analysis is a novel method of assessing measurement characteristics of monitoring tools. These data can be used by coaches and scientists to identify meaningful changes in common measures of fitness and fatigue in professional Australian football.
Clarke, AC, Ryan, S, Couvalias, G, Dascombe, BJ, Coutts, AJ & Kempton, T 2018, 'Physical demands and technical performance in Australian Football League Women's (AFLW) competition match-play.', Journal of Science and Medicine in Sport, vol. 21, no. 7, pp. 748-752.View/Download from: Publisher's site
To compare positional differences in the physical and technical demands of Australian Football League Women's (AFLW) match-play. A secondary aim was to examine the time course changes in activity profiles during AFLW match-play.Longitudinal observational study.Global positioning system data were collected from 26 players (6 positional groups) from the same club during seven AFLW matches. Absolute and relative physical performance data were categorised into total distance, high-speed running (>14.4kmh-1, HSR), very high-speed running (>18.0kmh-1, VHSR), and sprinting distance (>20.0kmh-1, Sprint). Technical performance data was obtained from a commercial statistics provider. A mixed model analysis was used to examine differences between positional groups and playing quarters.Absolute measures of running performance did not differ between position groups. Relative total distance was moderately greater (ES=∼0.80, p<0.05) for midfielders, small backs and small forwards (125-128mmin-1) than tall backs and tall forwards (102-107mmin-1). Relative HSR distance was greater (ES=∼0.73) for midfielders and small backs (∼28mmin-1) than tall backs (17mmin-1). Analysis of technical performance indicators showed: midfielders and small forwards had the most inside 50s; tall backs had the highest number of rebound 50s; tall forwards scored more goals; while midfielders made more tackles (p<0.05). All relative running performance measures were reduced in the fourth quarter when compared to the first and second quarters (ES=0.32-0.77).These data can be used as benchmarks for temporal analysis of AFLW match demands and assist in developing specific training strategies.
Dillon, PA, Kempton, T, Ryan, S, Hocking, J & Coutts, AJ 2018, 'Interchange rotation factors and player characteristics influence physical and technical performance in professional Australian Rules football.', Journal of Science and Medicine in Sport, vol. 21, no. 3, pp. 317-321.View/Download from: Publisher's site
OBJECTIVES: To examine the effects of match-related and individual player characteristics on activity profile and technical performance during rotations in professional Australian football. DESIGN: Longitudinal observational study. METHODS: Global positioning system data and player rating scores were collected from 33 professional Australian football players during 15 Australian football League matches. Player rating scores were time aligned with their relative total and high-speed running (HSR) distance (>20kmh(-1)) for each on ground rotation. Individual players' maximal aerobic running speed (MAS) was determined from a two-kilometre trial. A multilevel linear mixed model was used to examine the influence of rotations on physical activity profiles and skill execution during match play. RESULTS: Rotation duration and accumulated distance resulted in a trivial-to-moderate reduction in relative total and HSR distances as well as relative rating points. The number of disposals in a rotation had a small positive effect on relative total and HSR distances and a large positive effect on relative rating points. MAS was associated with a moderate-to-large increase in relative total distance, but had a large negative effect on relative rating points. Previous rotation time, stoppages and the number of rotations in the quarter had a trivial-to-small negative effect on relative total and HSR distances. A greater speed (mmin(-1)) was associated with a trivial increase in rating points during a rotation, while there was a trivial decrease in relative total distance as rating points increased. CONCLUSION: The complex relationship between factors that influence activity profile and technical performance during rotations in Australian football needs to be considered when interpreting match performance.
Jenner, SL, Trakman, G, Coutts, A, Kempton, T, Ryan, S, Forsyth, A & Belski, R 2018, 'Dietary intake of professional Australian football athletes surrounding body composition assessment.', Journal of the International Society of Sports Nutrition, vol. 15, no. 1, pp. 43-43.View/Download from: Publisher's site
Sports Dietitians aim to assist in improving performance by developing nutrition knowledge (NK), enhancing dietary intake and optimising body composition of athletes. In a high-pressure environment, it is important to identify factors that may compromise an athlete's nutrition status. Body composition assessments are regularly undertaken in sport to provide feedback on training adaptions; however, no research has explored the impact of these assessments on the dietary intake of professional athletes.This cross-sectional study assessed dietary intake (7-day food diary), nutrition knowledge (Nutrition for Sport Knowledge Questionnaire) and body composition (Dual-energy X-ray absorptiometry) of 46 professional male Australian football (AFL) athletes during a 2017 pre-season training week (7 days) where body composition assessments were undertaken. Dietary intake was assessed against International Olympic Committee recommendations for professional athletes.Overall, no athlete met dietary their recommended energy intake (15 ± 1.1 vs. 9.1 ± 1.8 MJ, respectively) or carbohydrate recommendations (6-10 vs. 2.4 ± 0.9 g·kg-1·day-1). Only 54% met protein recommendations. Secondary analyses demonstrated significant associations between education status and energy intake (P < 0.04) and vegetable intake (P < 0.03), with higher levels of education being associated with higher intakes. A moderately positive association was observed between NK scores and meeting estimated energy requirements (r = 0.33, P = 0.03). NK scores were also positively associated with protein (r = 0.35, P = 0.02), fibre (r = 0.51, P = 0.001) and calcium intakes (r = 0.43, P = 0.004).This research identified that the dietary intake of professional AFL athletes during a pre-season training week where body composition assessments were undertaken did not meet current recommendations. Several factors may influence the dietary intake of AFL athletes, including lower education levels, poor NK and dietary intake r...
Ryan, S, Coutts, AJ, Hocking, J, Dillon, PA, Whitty, A & Kempton, T 2018, 'Physical Preparation Factors That Influence Technical and Physical Match Performance in Professional Australian Football.', International journal of sports physiology and performance, vol. 13, no. 8, pp. 1021-1027.View/Download from: Publisher's site
OBJECTIVES:To examine the collective influence of a range of physical preparation elements on selected performance measures during Australian football match play. DESIGN:Prospective and longitudinal. METHODS:Data were collected from 34 professional Australian football players from the same club during the 2016 Australian Football League competition season. Match activity profiles and acute (7-d) and chronic (3-wk) training loads were collected using global positioning system devices. Training response was measured by well-being questionnaires completed prior to the main training session each week. Maximal aerobic running speed (MAS) was estimated by a 2-km time trial conducted during preseason. Coach ratings were collected from the senior coach and 4 assistants after each match on a 5-point Likert scale. Player ratings were obtained from a commercial statistics provider. Fifteen matches were analyzed. Linear mixed models were constructed to examine the collective influence of training-related factors on 4 performance measures. RESULTS:Muscle soreness had a small positive effect (ES: 0.12) on Champion Data rating points. Three-week average high-speed running distance had a small negative effect (ES: 0.14) on coach ratings. MAS had large to moderate positive effects (ES: 0.55 to 0.47) on relative total and high-speed running distances. Acute total and chronic average total running distance had small positive (ES: 0.13) and negative (ES: 0.14) effects on relative total and high-speed running distance performed during matches, respectively. CONCLUSIONS:MAS should be developed to enhance players' running performance during competition. Monitoring of physical preparation data may assist in reducing injury and illness and increasing player availability but not enhance football performance.
Sullivan, C, Kempton, T, Ward, P & Coutts, AJ 2018, 'Factors associated with early career progression in professional Australian Football players.', Journal of sports sciences, vol. 36, no. 19, pp. 2196-2201.View/Download from: Publisher's site
This study examined the association between individual and team characteristics and the probability of being offered a second contract in professional Australian Football. Contract status was obtained from the AFL for players who were drafted in the AFL National Draft between 1999 and 2013 (n = 999). Individual player characteristics were retrieved from the AFL while variables relating to performance were accessed online via Champion Data®. A binary logistic regression examined the influence of each characteristic on the probability of a professional Australian Football player receiving a second contract. Receiver operating characteristic (ROC) curves and the associated AUC were used to assess the discriminant ability of both a training (n = 938) and test data set (n = 61). The characteristics that influenced the probability of receiving a second contract included first year debut (pr 0.606), draft order (pr - 0.126), draft year (pr 0.059), games played (pr 1.848), team state (pr 0.458), rising star nomination (pr 1.553) and team ladder position (pr -0.043) (χ2 (8) = 198.28, p < 0.001). The ROC curve demonstrated an AUC of 82.4% (training) and 76.0% (test). A combination of individual and team based characteristics are associated with early career progression in professional Australian Football.
Lovell, TWJ, Bocking, CJ, Fransen, J, Kempton, T & Coutts, AJ 2018, 'Factors affecting physical match activity and skill involvement in youth soccer', Science and Medicine in Football, vol. 2, no. 1, pp. 58-65.View/Download from: Publisher's site
Bilsborough, JC, Kempton, T, Greenway, K, Cordy, J & Coutts, AJ 2017, 'Longitudinal Changes and Seasonal Variation in Body Composition in Professional Australian Football Players.', International Journal of Sports Physiology and Performance, vol. 12, no. 1, pp. 10-17.View/Download from: Publisher's site
To compare development and variations in body composition of early, mid and late career professional Australian Football (AF) players over three successive seasons.Regional and total body composition body (body mass (BM), fat mass (FM), fat-free soft tissue mass (FFSTM), and bone mineral content (BMC)) was assessed four times, at the same time of each season: 1) start pre-season (SP); 2) end pre-season (EP); mid-season (MS); and end-season (ES) from 22 professional AF players using pencil beam dual energy x-ray absorptiometry. Nutritional intake for each player was evaluated concomitantly using 3-day food diaries. Players were classified according to their age at the beginning of the observational period as either early (<21 y; N = 8), mid (21-25 y; N = 9) or late (>25 y; N = 5) career athletes.Early career players had lower FFSTM, BMC and BM compared to mid and late throughout. FM and %FM had greatest variability, particularly in the early career players. FM reduced and FFSTM increased from SP to EP, whilst FM and FFSTM decreased from EP to MS. FM increased and FFSTM decreased from MS to ES, whilst FM and FFSTM increased during the off-season.Early career players may benefit from greater emphasis upon specific nutrition and resistance training strategies aimed at increasing FFSTM, whilst all players should balance training and diet towards the end of season to minimise increases in FM.
Kempton, T, Sirotic, AC & Coutts, AJ 2017, 'A Comparison of Physical and Technical Performance Profiles Between Successful and Less-Successful Professional Rugby League Teams.', International Journal of Sports Physiology and Performance, vol. 12, no. 4, pp. 520-526.View/Download from: Publisher's site
This was the first study to examine differences in physical and technical performance profiles using a large sample of match observations drawn from successful and less-successful professional rugby league teams.Match activity profiles were collected using global positioning satellite (GPS) technology from 29 rugby league players from a successful team during 24 games and 25 players from a less-successful team during 18 games throughout two separate competition seasons. Technical performance data were obtained from a commercial statistics provider. A progressive magnitude based statistical approach was used to compare differences in physical and technical performance variables between the reference teams.There were no clear differences in playing time, nor absolute and relative total distances or LSR distances between successful and less-successful teams. The successful team had possibly to very likely lower higher-speed running demands and likely fewer physical collisions than the less-successful team, although they likely to most likely demonstrated more accelerations and decelerations and likely higher average metabolic power. The successful team very likely gained more territory in attack, very likely had more possession and likely committed fewer errors. In contrast, the less-successful team was likely required to attempt more tackles, most likely missed more tackles and very likely had a lower effective tackle percentage.In the present study, successful match performance was not contingent on higher match running outputs or more physical collisions, rather proficiency in technical performance components better differentiated between successful and less-successful teams.
Ryan, S, Coutts, AJ, Hocking, J & Kempton, T 2017, 'Factors Affecting Match Running Performance in Professional Australian Football.', International Journal of Sports Physiology and Performance, vol. 12, no. 9, pp. 1199-1204.View/Download from: Publisher's site
PURPOSE: To examine the influence of a range of individual player characteristics and match-related factors on activity profiles during professional Australian football matches. METHODS: Global positioning system (GPS) profiles were collected from 34 professional Australian football players from the same club over 15 competition matches. GPS data were classified into relative total and high-speed running (HSR; >20 km·h(-1)) distances. Individual player aerobic fitness was determined from a two-kilometre time trial conducted during the pre-season. Each match was classified according to match location, season phase, recovery length, opposition strength and match outcome. The total number of stoppages during the match was obtained from a commercial statistics provider. A linear mixed model was constructed to examine the influence of player characteristics and match related factors on both relative total and high-speed running outputs. RESULTS: Player aerobic fitness had a large effect on relative total and HSR distances. Away matches and matches lost produced only small reductions to relative HSR distances, while the number of rotations also had a small positive effect. Matches won, an increased number of player rotations and playing against strong opposition all resulted in small to moderate increases in relative total distance, while early season phase, increased number of stoppages and away matches resulted in small to moderate reductions in relative total distance Conclusions: There is a likely interplay of factors that influence running performance during Australian football matches. Our results highlight the need to consider a variety of contextual factors when interpreting physical output from matches.
Kempton, T & Coutts, AJ 2016, 'Factors affecting exercise intensity in professional rugby league match-play.', Journal of Science and Medicine in Sport, vol. 19, no. 6, pp. 504-508.View/Download from: Publisher's site
To examine the effects of match-related and individual player characteristics on running performance in professional rugby league matches.Longitudinal observational study.Global positioning system (GPS) and technical performance measures (attacking involvements and tackles made) were collected from 23 players competing in the National Rugby League (NRL) over 24 matches during a season. The GPS data were categorised into relative total distance (mmin(-1)) and relative high-speed running distance (HSR mmin(-1), >14.4kmh(-1)). Each match was classified according to season phase, location, recovery length, opposition strength and result. Individual player fitness status was obtained from a 1.2-km shuttle run test conducted prior to the start of the season. Two separate linear mixed models were constructed to examine the influence of match-related and individual player characteristics on relative total and HSR distances.Matches played away from home, early in the season and following short recovery cycles were associated with reduced relative total and HSR distances. Matches won contained less relative total and HSR distance; whereas only HSR distance was higher against weaker opposition. The total time the ball was out of play reduced relative total but not HSR distances. The number of defensive but not attacking involvements influenced both physical performance measures. Finally, player fitness was positively related to both relative total and HSR distances.There appears to be a complex interplay of factors affecting match-running performance in rugby league. The results underline the importance of considering contextual factors when analysing rugby league match-activity profiles.
Kempton, T, Kennedy, N & Coutts, AJ 2016, 'The expected value of possession in professional rugby league match-play', JOURNAL OF SPORTS SCIENCES, vol. 34, no. 7, pp. 645-650.View/Download from: Publisher's site
Coutts, AJ, Kempton, T, Sullivan, C, Bilsborough, J, Cordy, J & Rampinini, E 2015, 'Metabolic power and energetic costs of professional Australian Football match-play', JOURNAL OF SCIENCE AND MEDICINE IN SPORT, vol. 18, no. 2, pp. 219-224.View/Download from: Publisher's site
Kempton, T & Coutts, AJ 2015, 'Physical and Technical Demands of Rugby League 9s Tournament Match Play: A Preliminary Study', INTERNATIONAL JOURNAL OF SPORTS PHYSIOLOGY AND PERFORMANCE, vol. 10, no. 6, pp. 774-779.View/Download from: Publisher's site
Kempton, T, Sirotic, AC & Coutts, AJ 2015, 'An integrated analysis of match-related fatigue in professional rugby league', Journal of Sports Sciences, vol. 33, no. 1, pp. 39-47.View/Download from: Publisher's site
This study examined the changes in external outputs, including metabolic power variables, and internal response whilst considering contextual factors on physical performance variables during rugby league match play. Physical performance (total distance, high-speed running and high-power distances, average metabolic power), heart-rate (percentage heart-rate peak and training impulse), collisions (attacking and defensive) and contextual (time in attack, time in defence, time out of play) data were collected from 18 rugby league players during 38 games throughout two National Rugby League seasons. Physical variables were highest in the first 10-min period of each half (P < 0.001). Heart-rate indices peaked in the second 10-min period and were lower during second half periods (P < 0.001). Few differences existed in collisions and contextual factors across 10-min periods. Physical variables were highest during the first 5-min period compared to the final (P < 0.001). There was no difference in heart-rate response, attacking collisions or contextual factors between these periods. Following the peak 5-min period in the match, there were reductions in physical, heart-rate, defensive collisions and contextual factors (P < 0.001). The data show temporal changes in physical performance, heart-rate response and collisions during rugby league match play, although these are affected by contextual factors.
Kempton, T, Sirotic, AC, Rampinini, E & Coutts, AJ 2015, 'Metabolic power demands of rugby league match-play', International Journal of Sports Physiology and Performance, vol. 10, no. 1, pp. 23-28.View/Download from: Publisher's site
Kempton, T, Sullivan, C, Bilsborough, JC, Cordy, J & Coutts, AJ 2015, 'Match-to-match variation in physical activity and technical skill measures in professional Australian Football', Journal Of Science And Medicine In Sport, vol. 18, no. 1, pp. 109-113.View/Download from: Publisher's site
Objectives To determine the match-to-match variability in physical activity and technical performance measures in Australian Football, and examine the influence of playing position, time of season, and different seasons on these measures of variability Design Longitudinal observational study. Methods Global positioning system (GPS), accelerometer and technical performance measures (total kicks, handballs, possessions and Champion Data rank) were collected from 33 players competing in the Australian Football League over 31 matches during 2011-2012 (N = 511 observations). The GPS data were categorised into total distance, mean speed (m·min-1), high-speed running (HSR, >14.4 km·h-1), very high-speed running (VHSR, >19.9 km·h-1), and sprint (>23.0 km·h-1) distance whilst player load was collected from the accelerometer. The data was log transformed to provide coefficient of variation (CV) and the between subject standard deviation (expressed as percentages). Results Match-to-match variability was increased for higher speed activities (HSR, VHSR, sprint distance, CV%: 13.3 - 28.6%) compared to global measures (speed, total distance, player load, CV%: 5.3 - 9.2%). The between-match variability was relativity stable for all measures between and within AFL seasons, with only few differences between positions. Higher speed activities (HSR, VHSR, sprint distance), but not mean speed, total distance nor player load, were all higher in the final third phase of the season compared to the start of the season.
Moreira, A, Kempton, T, Aoki, MS, Sirotic, AC & Coutts, AJ 2015, 'The Impact of 3 Different-Length Between-Matches Microcycles on Training Loads in Professional Rugby League Players', INTERNATIONAL JOURNAL OF SPORTS PHYSIOLOGY AND PERFORMANCE, vol. 10, no. 6, pp. 767-773.View/Download from: Publisher's site
This study examined the birth distribution for adolescent (i.e. <20 years) and mature age players (i.e. =20 years) selected in the Australian Football League (AFL) National Draft between 2001 and 2012. Birth-date information was accessed for all first time AFL national draftees and players were then classified as either adolescent (N = 736) or mature age (N = 70) draftees. Chi-squared analysis showed a clear bias in the birth distribution of adolescent draftees towards players born in the first part of the classification period for both quartile (P < 0.001) and half-year (P < 0.001) compared to the Australian national population. There was a reverse relative age effect (RAE) for mature age draftees, with a significant bias towards players born in the latter part of the selection period for both quartile (P = 0.047) and half-year (P = 0.028) compared to the Australian national population. The selection bias towards relatively older players in adolescent AFL draftees may be related to advanced physical and psychological maturity, and exposure to higher-level coaching compared to their younger counterparts. The reverse RAE in mature age draftees is a novel finding and supports the need for strategies to encourage continued participation pathways for talented Australian football players born later in the selection year
Kempton, T, Sirotic, AC & Coutts, AJ 2014, 'Between match variation in professional rugby league competition', Journal Of Science And Medicine In Sport, vol. 17, no. 4, pp. 404-407.View/Download from: Publisher's site
Objectives To assess between match variability of physical performance measures over both the total and sub sections of the match in professional rugby league competition. Design Longitudinal observational study. Methods Global positioning system (GPS) data were collected from 24 players from the same team competing in the National Rugby League (NRL) competition over 23 matches during 2011 season. The GPS data were categorised into total distance, high-speed running (>15 km h-1) and very high-speed running (>21 km h-1) distance for discrete reference periods (10 min, 20 min, 40 min and 80 min). The data was then log transformed to provide the coefficient of variation (CV) and the between subject standard deviation (both expressed as percentages). Results The data show that the between match variability is greater for high-speed (CV 14.6%) and very-high speed (CV 37.0%) running compared to total distance (CV 3.6%). Within each speed category, the variability of performance tended to increase as the duration of the reference period decreased.
Kempton, T, Sirotic, AC, Cameron, M & Coutts, AJ 2013, 'Match-related fatigue reduces physical and technical performance during elite rugby league match-play: a case study.', Journal of Sports Sciences, vol. 31, no. 16, pp. 1770-1780.View/Download from: Publisher's site
Abstract This study examined the influence of match-related fatigue on physical and technical skill performance in ball playing positions at two different levels of rugby league competition. Time-motion analyses were performed using global positioning systems from 6 elite National Rugby League (NRL) and 11 junior elite National Youth Competition (NYC) players from 45 matches. A standardised 5-point technical coding criteria was used to qualitatively assess skill involvements during match-play. The distance travelled in the 0-5 and 40-45 min period were significantly higher compared to the 30-35, 35-40, 70-75 and 75-80 min periods (P < 0.001). Skill rating and involvements were higher in the 0-5 and 40-45 min compared to 70-75 and 75-80 min periods (P < 0.001 and P < 0.001, respectively).There was no significant difference in the number of physical collisions between the 5-min periods (P = 0.051). Following the peak 5-min bout of exercise intensity there were reductions in distance (P < 0.001), quality of skill involvements (P < 0.001), number of involvements (P < 0.001) and collisions (P < 0.001). Elite NRL and NYC "ball players" exhibit reductions in physical performance towards the end of matches and following brief periods of intense exercise. There also appears to be a reduction in technical performance for NRL and NYC ball players, which may be attributable to match-related fatigue.
Moreira, A, Costa, E, De Moura, N, Kempton, T, Coutts, AJ & Aoki, MS 2013, 'Monitoring internal training load and mucosal immune responses in futsal athletes', Journal of Strength and Conditioning Research, vol. 27, no. 5, pp. 1253-1259.View/Download from: Publisher's site
The purpose of this study was to examine the changes in salivary immunoglobulin A (SIgA), cortisol, and upper respiratory tract infection (URTI) and their relationships with training loads (TLs) during a 4-week period of intensive training during the competitive season in elite Brazilian futsal players.
Kennett, DC, Kempton, T & Coutts, AJ 2012, 'Factors affecting exercise intensity in rugby-specific small-sided games', Journal of Strength and Conditioning Research, vol. 26, no. 8, pp. 2037-2042.View/Download from: Publisher's site
Factors affecting exercise intensity in rugby-specific small-sided games. J Strength Cond Res 26(8): 2037-2042, 2012-Small-sided games (SSGs) have been suggested as a method for concurrently training physical, technical and tactical capabilities of rugby union players.
Coutts, AJ, Crowcroft, S & Kempton, T 2017, 'Developing athlete monitoring systems: Theoretical basis and practical applications1' in Sport, Recovery, and Performance: Interdisciplinary Insights, Routledge, UK, pp. 19-32.View/Download from: Publisher's site
Athlete monitoring is now common practise in high-performance sport. Fundamentally, athlete monitoring involves quantifying the athletes training load and their responses to that training. The main reasons for monitoring athletes are that it can provide information to refine the training process, increase athlete performance readiness and reduce risk of injury and illness. Through a systematic approach to athlete monitoring an improved understanding of the complex relationships between training, performance, and injury can be obtained. The purpose of this chapter is to examine the training theory that underpins athlete monitoring and discuss the key components of an athlete monitoring system. Additionally, a discussion of methods used to analyse and interpret these data will also be provided.
Kempton, T & Coutts, AJ 2013, 'Prior high-intensity intermittent running reduces exercise intensity and skill performance in small-sided rugby games' in Nunome, H, Drust, B & Dawson, B (eds), Science and Football VII: The Proceedings of the Seventh World Congress on Science and Football, Routledge, USA, pp. 261-266.View/Download from: Publisher's site
To date only one study has examined whether skill-related performance is affected by match-related fatigue in a similar manner as physical performance during professional soccer match play (Carling and Dupont, 2011). Carling and colleagues reported that while HIR distance declined between halves and during the final third of matches, it was not associated with a reduction in technical skill performance. However, the assessment of the influence of fatigue on technical performance during competition is problematic due to the possible impact of psychological, tactical and situational factors. To overcome this, recent studies have examined the influence of physical fatigue on skill tests in controlled matchsimulations (Lyons et al., 2006; Rampinini et al., 2008; Royal et al., 2006; Sunderland, 2005; Young et al., 2010). Most (Lyons et al., 2006; Rampinini et al., 2008; Sunderland, 2005) of these studies have reported that skilled performance is impaired by match-related fatigue. At present it is not known if acute physical fatigue influences skill performance in SSGs.