School contextual correlates of physical activity among a national adolescent sample

Schools are an important context to promote adolescent physical activity (PA). However, following ecologic frameworks, little is known about the influence of multiple school contextual levels - environment and policy - on adolescent PA. This study aimed to examine associations of school neighborhood environment factors and state laws with PA, and the moderating effects of school neighborhood socioeconomic status (SES) on these associations. Analyses used cross-sectional data from a national sample of middle (n = 387) and high (n = 591) school adolescents from the Family Life, Activity, Sun, Health, and Eating study conducted in 2014. Outcomes included self-report school-time PA and active transport to/from school (ATS), and estimated minutes/week of school-related moderate-to-vigorous PA (MVPA) and total MVPA. Separate regression models for middle and high school respondents examined state laws (school PA or physical education (PE) time requirements) and school neighborhood factors (density, age, and commute times), and their interactions with school neighborhood SES, in relation to each PA outcome, adjusting for socio-demographic and psychosocial factors. The high school models showed strong PE laws (B[SE]: 0.3[0.1], p = 0.02) and any PA law (B[SE]: 0.3[0.1], p = 0.0003) were related to higher school-time PA, and shorter school neighborhood commute times were related to lower ATS (OR [95% CI]: 0.4 [0.2-0.7]). We found similar associations with estimated school-related MVPA. The middle school models showed no significant state law or school neighborhood main effects. Interactions with school neighborhood SES were not significant. Our findings provide further support for state laws to promote PA in school regardless of school neighborhood SES.