Differences in external game loads are inconsistent and predominantly small between seasons in semi-professional, male rugby league players: a three-year team-based observational study

Background: Although external game loads have been readily examined across acute timeframes within male rugby league seasons, longitudinal analysis between seasons remain limited. Consequently, this study compared game demands during separate seasons in male, rugby league players. Methods: One semi-professional team competing in a men’s state-level Australian rugby league competition was monitored during all games for three seasons (2022–2024). External load variables were measured with global positioning system devices. Linear mixed-model and Hedge’s gav effect sizes were used to compare variables between seasons within the same players (participated in all seasons, n = 6) and within the entire team (participated in any season, n = 33). Results: Within-player and team-level analyses revealed playing duration (p < 0.01, gav (range) = 0.44–0.63), total distance (p < 0.05, gav = 0.33–0.51) and peak speed (p < 0.01, gav = 0.35–0.52) were significantly lower, while relative (per min) distance (p < 0.05, gav = 0.35–0.52), accelerations (p < 0.01, gav = 0.57–0.69) and decelerations (p < 0.01, gav = 0.47–0.60) were significantly higher in 2022 compared to other seasons. Non-significant differences were evident between 2023 and 2024 for all variables (p > 0.05, gav = 0.03–0.23), except relative high-speed running distance, which was higher in 2024 in team-level analyses (p = 0.01, gav = 0.31). Conclusions: The increased playing duration, total distance and peak speed, and decreased relative external load variables in 2023–2024 compared to 2022 were mostly small in magnitude, indicating seasonal fluctuations were relatively subtle at player and team levels. These findings suggest practitioners working with semi-professional, male rugby league players could develop long-term plans for upcoming seasons based on typical game data from previous seasons, but plans should be adaptable given the inconsistent and tenuous way loads may vary longitudinally.

Training load; Monitoring; Football; Team sport; GPS; Performance; Longitudinal

[1] International Rugby League. Member nations. 2024. Available at: https://www.intrl.sport/member-nations (Accessed: 01 December 2024).

[2] Glassbrook DJ, Doyle TLA, Alderson JA, Fuller JT. The demands of professional rugby league match-play: a meta-analysis. Sports Medicine—Open. 2019; 5: 24.

[3] Hudson S, Fish M, Haines M, Harper L. Monitoring the physical demands of training in rugby league: the practices and perceptions of practitioners. Science and Medicine in Football. 2024; 8: 293–300.

[4] Hausler J, Halaki M, Orr R. Application of global positioning system and microsensor technology in competitive rugby league match-play: a systematic review and meta-analysis. Sports Medicine. 2016; 46: 559–588.

[5] Jeffries A, Marcora S, Coutts A, Wallace L, McCall A, Impellizzeri F. Development of a revised conceptual framework of physical training for use in research and practice. Sports Medicine. 2022; 52: 709–724.

[6] Torres-Ronda L, Beanland E, Whitehead S, Sweeting A, Clubb J. Tracking systems in team sports: a narrative review of applications of the data and sport specific analysis. Sports Medicine—Open. 2022; 8: 15.

[7] West S, Clubb J, Torres-Ronda L, Howells D, Leng E, Vescovi J, et al. More than a metric: how training load is used in elite sport for athlete management. International Journal of Sports Medicine. 2021; 42: 300–306.

[8] Doering T, Elsworthy N, Callaghan D, Jones B, Teramoto M, Scanlan A. A comparison of activity demands between trial matches and in-season matches across multiple teams and seasons in semi-professional, male rugby league players. Biology of Sport. 2023; 40: 1239–1247.

[9] Johnstone R, Devlin P, Wade J, Duthie G. There is little difference in the peak movement demands of professional and semi-professional rugby league competition. Frontiers in Physiology. 2019; 10: 1285.

[10] Floersch S, Vidden C, Askow A, Jones A, Fields J, Jagim A. Seasonal changes in match demands and workload distribution in collegiate soccer across two seasons. The Journal of Strength and Conditioning Research. 2024; 38: 1440–1446.

[11] Barnes C, Archer D, Hogg B, Bush M, Bradley P. The evolution of physical and technical performance parameters in the English Premier League. International Journal of Sports Medicine. 2014; 35: 1095–1100.

[12] Zhou C, Gómez M, Lorenzo A. The evolution of physical and technical performance parameters in the Chinese Soccer Super League. Biology of Sport. 2020; 37: 139–145.

[13] Allen T, Taberner M, Zhilkin M, Rhodes D. Running more than before? The evolution of running load demands in the English Premier League. International Journal of Sports Science & Coaching. 2024; 19: 779–787.

[14] Akyildiz Z, Nobari H, González-Fernández F, Praça C, Sarmento H, Guler A, et al. Variations in the physical demands and technical performance of professional soccer teams over three consecutive seasons. Scientific Reports. 2022; 12: 2412.

[15] Rennie G, Hart B, Dalton-Barron N, Weaving D, Williams S, Jones B. Longitudinal changes in Super League match locomotor and event characteristics: a league-wide investigation over three seasons in rugby league. PLOS ONE. 2021; 16: e0260711.

[16] Evans SD, Brewer C, Haigh JD, McDonough A, Lake M, Morton JP, et al. The change in external match loads and characteristics for a newly promoted European super league rugby league team over a three season period. Science and Medicine in Football. 2018; 2: 309–314.

[17] Delves R, Thornton H, Hodges J, Cupples B, Ball K, Aughey R, et al. The introduction of the six-again rule has increased acceleration intensity across all positions in the National Rugby League competition. Science and Medicine in Football. 2023; 7: 47–56.

[18] McKay A, Stellingwerff T, Smith E, Martin D, Mujika I, Goosey-Tolfrey V, et al. Defining training and performance caliber: a participant classification framework. International Journal of Sports Physiology and Performance. 2022; 17: 317–331.

[19] Dalton-Barron N, Whitehead S, Roe G, Cummins C, Beggs C, Jones B. Time to embrace the complexity when analysing GPS data? A systematic review of contextual factors on match running in rugby league. Journal of Sports Sciences. 2020; 38: 1161–1180.

[20] Mooney T, Malone S, Izri E, Dowling S, Darragh I. The running performance of elite U20 Gaelic football match-play. Sport Sciences for Health. 2021; 17: 771–779.

[21] Dawson L, McErlain-Naylor S, Devereux G, Beato M. Practitioner usage, applications, and understanding of wearable GPS and accelerometer technology in team sports. The Journal of Strength and Conditioning Research. 2024; 38: e373–e382.

[22] Kuznetsova A, Brockhoff P, Christensen R. lmerTest package: tests in linear mixed effects models. Journal of Statistical Software. 2017; 82: 1–26.

[23] Newans T, Bellinger P, Drovandi C, Buxton S, Minahan C. The utility of mixed models in sport science: a call for further adoption in longitudinal data sets. International Journal of Sports Physiology and Performance. 2022; 17: 1289–1295.

[24] Lüdecke D, Patil I, Ben-Shachar M, Wiernik B, Waggoner P, Makowski D. see: an R package for visualizing statistical models. The Journal of Open Source Software. 2021; 6: 3393.

[25] Lüdecke D, Ben-Shachar M, Patil I, Waggoner P, Makowski D. performance: An R package for assessment, comparison and testing of statistical models. The Journal of Open Source Software. 2021; 6: 3139.

[26] Lakens D. Calculating and reporting effect sizes to facilitate cumulative science: a practical primer for t-tests and ANOVAs. Frontiers in Pyschology. 2013; 4: 863.

[27] Newans T, Bellinger P, Drovandi C, Buxton S, Minahan C. The utility of mixed models in sport science: a call for further adoption in longitudinal data sets. International Journal of Sports Physiology and Performance. 2022; 17: 1289–1295.

[28] Cumming G. Understanding the new statistics: effect sizes, confidence intervals, and meta-analysis. 1st edn. Routledge: New York. 2013.

[29] Hopkins W, Marshall S, Batterham A, Hanin J. Progressive statistics for studies in sports medicine and exercise science. Medicine and Science in Sports and Exercise. 2009; 41: 3–13.

[30] Brown D, Arnold R. Sports performers’ perspectives on facilitating thriving in professional rugby contexts. Psychology of Sport and Exercise. 2019; 40: 71–81.

[31] Duthie G, Thornton H, Delaney J, McMahon J, Benton D. Relationship between physical performance testing results and peak running intensity during professional rugby league match play. The Journal of Strength and Conditioning Research. 2020; 34: 3506–3513.

[32] Harper D, McBurnie A, Santos T, Eriksrud O, Evans M, Cohen D, et al. Biomechanical and neuromuscular performance requirements of horizontal deceleration: a review with implications for random intermittent multi-directional sports. Sports Medicine. 2022; 52: 2321–2354.

[33] Janetzki S, Bourdon P, Norton K, Lane J, Bellenger C. Evolution of physical demands of Australian Football League matches from 2005 to 2017: a systematic review and meta-regression. Sports Medicine—Open. 2021; 7: 28.

[34] Gabbett T. Sprinting patterns of National Rugby League competition. The Journal of Strength and Conditioning Research. 2012; 26: 121–130.

[35] Delaney J, Thornton H, Duthie G, Dascombe B. Factors that influence running intensity in interchange players in professional rugby league. International Journal of Sports Physiology and Performance. 2016; 11: 1047–1052.

[36] Delaney J, Duthie G, Thornton H, Scott T, Gay D, Dascombe B. Acceleration-based running intensities of professional rugby league match play. International Journal of Sports Physiology and Performance. 2016; 11: 802–809.

[37] Waldron M, Highton J, Daniels M, Twist C. Preliminary evidence of transient fatigue and pacing during interchanges in rugby league. International Journal of Sports Physiology and Performance. 2013; 8: 157–164.

[38] Hands D, Janse de Jonge X, Livingston G, Borges N. The effect of match location and travel modality on physical performance in A-League association football matches. Journal of Sports Sciences. 2023; 41: 565–572.

[39] Ryan S, Coutts A, Hocking J, Kempton T. Factors affecting match running performance in professional Australian football. International Journal of Sports Physiology and Performance. 2017; 12: 1199–1204.

[40] McGuckin T, Sinclair W, Sealey R, Bowman P. Players’ perceptions of home advantage in the Australian rugby league competition. Perceptual and Motor Skills. 2015; 121: 666–674.

[41] Dalton-Barron N, Palczewska A, McLaren S, Rennie G, Beggs C, Roe G, et al. A league-wide investigation into variability of rugby league match running from 322 Super League games. Science and Medicine in Football. 2021; 5: 225–233.

[42] Sirotic A, Coutts A, Knowles H, Catterick C. A comparison of match demands between elite and semi-elite rugby league competition. Journal of Sports Sciences. 2009; 27: 203–211.

[43] Russell J, McLean B, Impellizzeri F, Strack D, Coutts A. Measuring physical demands in basketball: an explorative systematic review of practices. Sports Medicine. 2021; 51: 81–112.