The longitudinal relationship between generalized self-efficacy and physical activity in school-aged children.

Our understanding of the longitudinal relationship between generalized self-efficacy (GSE) and physical activity in children and youth is limited. The purpose of this study was to investigate the effect of GSE towards physical activity on sedentary behaviours and physical activity in school-aged children over time. A total of 2278 nine-year-old children (1120 girls and 1158 boys) were recruited at baseline and followed for seven waves of data collection from 2005 to 2008. All children completed questionnaires at each wave assessing their GSE (adequacy, predilection, and enjoyment), sedentary behaviours, free play, and organized activity. Mixed-effects models were used to estimate changes in physical activity and GSE within individuals over time, controlling for gender and motor ability. The results showed that participation in free play significantly increased over time, whereas organized activity significantly decreased over the same period. Children with high perceived adequacy and predilection had higher free play and organized activity participation relative to other children over time. However, the effect of perceived adequacy diminished over time, while the gaps between groups with different levels of predilection widened over time. While sedentary behaviours were lower over time in children with high predilection, these behaviours were consistently higher in children with high enjoyment. The differences in sedentary behaviours between groups increased over time for both predilection and enjoyment. This study highlights the importance of different components of GSE on physical activity participation. In addition, interventions targeting the enhancement of predilection may facilitate physical activity and reduce sedentary behaviours.