Association Between the Built Environment in School Neighborhoods With Physical Activity Among New York City Children, 2012.

INTRODUCTION
The benefits of physical activity for health and well-being are well established, yet built environment characteristics in the school neighborhood may constrain students' ability to engage in physical activity and contribute to the considerable variation in physical activity among students at different schools.

METHODS
Baseline data from the Food, Health and Choices obesity prevention trial were used to create multilevel linear models of the relationship between fifth-grade students' (n = 952) physical activity and related psychosocial factors and characteristics of the built environment of the school's neighborhood (park access, public transportation density, total crime, and walkability), controlling for age and body mass index z scores.

RESULTS
Total crime was inversely associated with boys' light physical activity duration (β = -0.189; P = .02) and behavioral intention for physical activity (β = -0.178; P = .03). Boys' habit strength for physical activity was positively associated with public transportation density (β = 0.375; P = .02) and negatively associated with total crime (β = -0.216; P = .01), explaining 67% of between-school variation. Girls' frequency of light physical activity was positively associated with park access (β = 0.188; P = .04). Built environment characteristics explained 97% of the between-school variation in girls' self-efficacy in walking for exercise.

CONCLUSIONS
Characteristics of the built environment surrounding schools were associated with and explain between-school variation in students' physical activity and several theory-based psychosocial factors. Partnerships between public health practitioners, policy makers, and school administrators may be warranted to shape the school neighborhood, specifically to decrease crime rates and increase park access, to encourage physical activity in youth.