Ashley Cripps1, Luke Hopper1,2, Christopher Joyce1 Anthropometric, fitness and coaches’ perceptions of technical skill favour early maturing adolescent Australian Footballers. Ashley Cripps1, Luke Hopper1,2, Christopher Joyce1 1School of Health Sciences, University of Notre Dame Australia, Fremantle, WA 2 Western Australian Academy of Performing Arts, Edith Cowan University, Mount Lawley, WA Anthropometric, physiological and skills outcomes for late, average and early maturational groups (mean ± standard deviation). Introduction Adolescent sports are typically age stratified by one or two years in an attempt to ensure competition equity and player safety. However, despite age stratification large differences in biological maturity still exist. Adolescent athletes of advance maturity are at a significant performance advantage with clear links evident between maturity, physical testing and match performance. However, football is a multi-factorial sport where technical skill efficiency is also critical to individual and team success. The impact that maturational variation has on technical and perceived skill efficiency in adolescent Footballers is yet to be explored.   Maturational Status Late Average Early Cohen’s d Anthropometric Height (m) 1.70 ± 0.05 1.76 ± 5.25 a 1.84 ± .05a,b 2.67 Weight (kg) 60.03 ± 6.29 67.56 ± 6.26 a 76.16 ± 6.69 a,b 2.49 Physical SVJ (m) 0.48 ± 0.07 0.52 ± 0.06 a 0.54 ± 0.11 a 0.76 RVJ Left (m) 0.58 ± 0.08 0.61 ± 0.10 a 0.65 ± 0.08 a,b 0.94 RVJ Right (m) 0.54 ± 0.09 0.58 ± 0.09 a 0.62 ± 0.08 a,b 0.99 20m Sprint (sec) 3.24 ± 0.18 3.16 ± 0.11 3.11 ± 0.13 a,b 0.83 Shuttle Distance (m) 2177.22 ± 282.52 2100.81 ± 307.91 2080.00 ± 289.26 0.07 Technical Skill Kicking Test 16.48 ± 4.23 15.81 ± 4.43 17.56 ± 4.21 0.26 Handball Test 19.54 ± 6.84 20.17 ± 5.06 19.92 ± 5.45 0.06 Aims To determine how maturational in Australian Footballers impacts on: Anthropometric and physical testing Technical skill efficiency Coaches’ perceptions of skill efficiency Methods Participants recruited from Western Australian Football league (n=225, age 15.64 ± 0.29 years). Participants completed anthropometric, physical, and technical skill tests. Physical testing included; standing and running vertical jumps, 20m sprints and the Multi-Stage Fitness Test. The technical skills assessed were kicking and handball efficiency, using the Australian Football Leagues kicking and handball tests. Senior coaches for each team (n=7) were recruited to provide subjective ratings of athletes technical skills. Maturation groups were derived from estimations of years from peak height velocity, with participants classified as either late, average or early maturing. Between group analysis of variance was used to test differences between the maturational groups and independent variables measured. a significantly different (p<0.05) from Late; b significantly different (p<0.05) from Average. Coaches' perceptions of skill for late, average and early maturational groups (mean ± standard deviation).   Maturational Status Late Average Early Cohen’s d Kicking 2.54 ± 0.51 2.73 ± 0.90 2.67 ± 0.84 0.19 Marking 2.33 ± 0.48 2.60 ± 0.75 a 3.10 ± 0.71a,b 1.27 Handball 2.54 ± 0.48 2.71 ± 0.80 2.93 ± 0.78 0.60 Clean Hands 2.63 ± 0.49 2.78 ± 0.81 3.13 ± 0.86 0.71 Ball Winning 2.63 ± 0.71 2.92 ± 0.89 3.17 ± 1.02 0.61 Overall Technical Rating 12.66 ± 2.12 13.75 ± 3.55 15.00 ± 3.49 a 0.81 Australian Football Leagues kicking and handball tests. a significantly different (p<0.05) from Late; b significantly different (p<0.05) from Average. Summary Early maturing footballers significantly taller, heavier and physically developed No concurrent advantage associated with technical skill efficiency Coaches’ perceived early maturing footballers to have significantly better overall technical skill and marking abilities Handball Test Kicking Test Results Biological maturity varying by up to 3.41 years between the most and least mature athletes, despite chronological age only differing by 0.43 years. Acknowledgments The University of Western Australia and the Western Australian Football Commission for their support with this project.