Rule modification in junior sport: Does it create differences in player movement?

OBJECTIVES To determine the effects of rule modification on player movement during matchplay in junior Australian football (AF). DESIGN Quasi-experimental study design. METHODS Time-motion analysis was used to record variables pertaining to player movement including total distance covered, high-speed running (HSR) distance (>14.4km/h) and HSR efforts. GPS data obtained from 145 players (7-12 years) were analysed across four junior AF leagues and three age group combinations (U8/U9, U9/U10 and U11/U12). The four leagues were collapsed into two separate conditions (compliant and non-compliant) based on their adherence to a modified junior sport policy. To control for the influence of age and physical maturity, a secondary analysis was performed on an adequately matched U8 subset of data (n=48). RESULTS Significant differences (p<0.05) were found between compliant and non-compliant leagues for age and all player movement variables, with participants in the compliant leagues achieving less player movement. Significant differences were also evident between conditions in the U8 subset in total and relative distance and HSR efforts, with moderate to very large differences (29-60%) observed for all player movement variables. CONCLUSIONS Rule modifications limits the extent and intensity of player movement in junior AF compared to standard playing conditions. The unintended effect of reduced physical activity with rule modifications should be compensated for with additional activities wherever possible. League administrators and policy makers should consider the objectives of rule modifications and weigh up both positive and negative outcomes.

[1]  J. Cook,et al.  Biological maturity influences running performance in junior Australian football. , 2013, Journal of science and medicine in sport.

[2]  J. Duda,et al.  Optimising physical activity engagement during youth sport: a self-determination theory approach , 2016, Journal of sports sciences.

[3]  Francisco M Argudo,et al.  Review of rule modification in sport. , 2011, Journal of sports science & medicine.

[4]  J. Cook,et al.  Influence of age and fitness on match and training activity profiles in junior Australian football , 2013 .

[5]  Aaron J. Coutts,et al.  Validity and reliability of GPS devices for measuring movement demands of team sports. , 2010, Journal of science and medicine in sport.

[6]  Andrew Dawson,et al.  Examining the AFL junior match policy for recruitment and retention , 2013 .

[7]  C. Finch,et al.  A prospective cohort study of the incidence of injuries among junior Australian football players: evidence for an effect of playing-age level , 2007, British Journal of Sports Medicine.

[8]  Jacob Cohen Statistical Power Analysis for the Behavioral Sciences , 1969, The SAGE Encyclopedia of Research Design.

[9]  Adrian J. Gray,et al.  Match Analysis and the Physiological Demands of Australian Football , 2010, Sports medicine.

[10]  Stuart J. Cormack,et al.  The validity and reliability of GPS units for measuring distance in team sport specific running patterns. , 2010, International journal of sports physiology and performance.

[11]  Chelsey R. Schlechter,et al.  Physical activity levels during youth sport practice: does coach training or experience have an influence? , 2017, Journal of sports sciences.

[12]  I. Janssen,et al.  Systematic review of the health benefits of physical activity and fitness in school-aged children and youth , 2010, The international journal of behavioral nutrition and physical activity.

[13]  Bruce Abernethy,et al.  Game-Based Training for Improving Skill and Physical Fitness in Team Sport Athletes , 2009 .

[14]  S. Marshall,et al.  Progressive statistics for studies in sports medicine and exercise science. , 2009, Medicine and science in sports and exercise.

[15]  J. Harvey,et al.  Participation in modified sports programs: a longitudinal study of children’s transition to club sport competition , 2015, BMC Public Health.

[16]  Franco M. Impellizzeri,et al.  Physiology of Small-Sided Games Training in Football , 2011, Sports medicine.

[17]  Mark R. Wilson,et al.  Playing by the Rules: A Developmentally Appropriate Introduction to Rugby Union , 2015 .

[18]  J. Jakicic,et al.  The influence of exercise and BMI on injuries and illnesses in overweight and obese individuals: a randomized control trial , 2010, The international journal of behavioral nutrition and physical activity.

[19]  J. L. Arias,et al.  Effect of the 3-Point Line Change on the Game Dynamics in Girls' Minibasketball , 2009, Research quarterly for exercise and sport.

[20]  B. Christine Green,et al.  Establishing and maintaining a modified youth sport program: lessons from Hotelling's location game. , 1998 .

[21]  Mary Duggan,et al.  New Canadian physical activity guidelines. , 2011, Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme.

[22]  Julen Castellano,et al.  Time–motion, heart rate, perceptual and motor behaviour demands in small-sides soccer games: Effects of pitch size , 2010, Journal of sports sciences.

[23]  Brian Dawson,et al.  Physiological responses and time–motion characteristics of various small-sided soccer games in youth players , 2009 .

[24]  F. Kew Game-Rules and Social Theory , 1992 .

[25]  C. Twist,et al.  Heart Rate Responses to Small-Sided Games Among Elite Junior Rugby League Players , 2010, Journal of strength and conditioning research.

[26]  Keith Davids,et al.  Effects of different practice task constraints on fluctuations of player heart rate in small-sided football games , 2014 .

[27]  P. Gastin,et al.  Late maturers at a performance disadvantage to their more mature peers in junior Australian football , 2014, Journal of sports sciences.

[28]  W. Strean Youth sport contexts: Coaches perceptions and implications for intervention , 1995 .