From motivation to movement: autonomous motivation and physical activity levels among students in the Global Health...

Little is known about how motivation relates to physical activity within large-scale school-based programs and whether this association varies according to contextual factors such as perceived school leader support, peer affiliation, or duration of program participation. This study examined the association between motivation for physical activity and physical activity levels among students participating in the Global Health Program (GHP) and tested whether this association was moderated by these contextual factors. Cross-sectional data were drawn from the Autumn 2024 baseline evaluation of the GHP, a school-based program implemented across 48 public schools in Québec, Canada. A total of 664 students completed an online questionnaire, with participants represented across 22 schools. Among students with valid age data, the mean age was 14.05 years (SD = 1.80), and 58% were boys. Motivation was assessed using the Behavioural Regulation in Exercise Questionnaire-2, and physical activity was assessed using the PAQ-C or PAQ-A according to school level. Linear mixed-effects models with a random intercept for school were used to examine associations between motivation and physical activity, adjusting for age, sex, and mother's education. Moderation analyses tested interactions between the Relative Autonomy Index (RAI) and perceived school leader support, peer affiliation, and years of participation. A higher RAI was associated with a higher physical activity score in the adjusted model ( $\hat{\beta }$ = 0.02, 95% CI [0.01, 0.03], p < 0.001). Identified regulation ( $\hat{\beta }$ = 0.30, 95% CI [0.24, 0.36], p < 0.001) and intrinsic regulation ( $\hat{\beta }$ = 0.28, 95% CI [0.22, 0.35], p < 0.001) showed the strongest positive associations with physical activity. Introjected regulation was also positively associated with physical activity ( $\hat{\beta }$ = 0.12, 95% CI [0.08, 0.17], p < 0.001), whereas amotivation and external regulation were not statistically significant. Perceived school leader support and peer affiliation did not significantly moderate the association between the RAI and physical activity. However, years of participation significantly moderated this association (interaction $\hat{\beta }$ = 0.004, 95% CI [0.001, 0.008], p = 0.022), with a stronger positive association among students reporting longer participation in the GHP. Autonomous motivation was positively associated with physical activity among students participating in the GHP, particularly identified and intrinsic regulation. These findings support the relevance of Self-Determination Theory for understanding physical activity in school-based programs, while longitudinal research is needed to clarify the direction of the observed associations and the role of continued program participation.