The association of social and school environments with moderate-to-vigorous intensity physical activity among school-aged children in south-central China: a mediation analysis

This study examined the associations between moderate-to-vigorous intensity physical activity (MVPA) and social support (SS), autonomous motivation (AM), community environment (CE), school environment (SE), and caregiver role modeling for physical activity (CRMPA) among school-aged children in south-central China. A multi-center survey was conducted with the recruitment of 706 children and their caregivers from six schools. MVPA was assessed using accelerometers over a one-week period, while the SS, AM, CE, SE, and CRMPA were assessed by validated questionnaires. Mediation analyses were used to evaluate the relationships between the aforementioned factors and MVPA. For girls, SS (standardized estimate β = 0.25, 95% CI [0.08, 0.50]) and CRMPA (β = 0.08, 95% CI [0.03, 0.15]) indirectly influenced MVPA through AM, with SS having a greater effect than CRMPA. However, the direct effect of SS on MVPA was not significant (β = 0.07, 95% CI [-0.22, 0.30]). In boys, SS had a direct effect on both MVPA (β = 0.27, 95% CI [0.03, 0.51]) and AM (β = 0.79, 95% CI [0.65, 0.89]). For both genders, no statistically significant effects of SE and CE on MVPA were observed. The findings identify SS as a prominent factor associated with MVPA, particularly for boys. For girls, MVPA was influenced through AM, which appeared to be supported by both SS and CRMPA.