Optimising physical activity engagement during youth sport

1 Research suggests participation in youth sport does not guarantee physical activity (PA) 2 guidelines are met. Studies indicate few children achieve recommended levels of moderate3 to-vigorous physical activity (MVPA) during their youth sport involvement, and habitual 4 levels of MVPA are below the recommended 60 minutes per day. Informed by self5 determination theory, this study examined whether the coach created social environment and 6 related player motivation predict variability in objectively measured MVPA within the youth 7 sport setting. Seventy three male youth sport footballers (Mage = 11.66 ± 1.62) completed a 8 multi-section questionnaire assessing their perceptions of the social environment created in 9 youth sport (autonomy supportive and controlling), and motivation towards their football 10 participation (autonomous and controlled). Intensity of PA during youth sport was measured 11 using accelerometers (GT3X, Actigraph). Results supported a model in which perceptions of 12 autonomy support significantly and positively predicted autonomous motivation towards 13 football, which in turn significantly and positively predicted youth sport MVPA (% time). A 14 significant indirect effect was observed for perceptions of autonomy support on youth sport 15 %MVPA via autonomous motivation. Conclusion: Results have implications for optimising 16 PA engagement during youth sport and increasing daily MVPA towards recommended and 17 health enhancing levels on youth sport days. 18