Location: Children's Nutrition Research CenterTitle: Active commuting to elementary school and adiposity: An observational study Author
Submitted to: Childhood Obesity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/15/2013
Publication Date: 2/1/2014
Citation: Mendoza, J.A., Liu, Y. 2014. Active commuting to elementary school and adiposity: An observational study. Childhood Obesity. 10(1):34-41. Interpretive Summary: Previous generations of US children walked or biked to school regularly, but few of today's children walk or bike to school. This decrease in walking or biking to school may be a missed opportunity for obesity prevention, but few long-term studies have examined this relationship. We studied the long-term relationship between walking or biking to school in kindergarten and obesity among US children. Kindergarteners who walked or biked to school developed lower 5th grade BMI z-scores compared to their peers who rode by car or bus to school. Also, children from less safe neighborhoods who walked or biked to school in kindergarten developed lower 5th grade BMI z-scores than their peers from more safe neighborhoods. Programs and policies to prevent childhood obesity should include promotion of walking and biking to school in kindergarten, and should also focus on increasing children's safety.
Technical Abstract: Active commuting to school (ACS; walking or cycling to school) appears promising for decreasing children's obesity risk, although long-term studies are sparse. The aim was to examine whether kindergarten ACS was associated with fifth grade adiposity. This study was a secondary analysis of the Early Childhood Longitudinal Study, Kindergarten (n = 7938). Enrollment in kindergarten (1998–1999) was nationally representative of the United States and follow-up occurred in 2004. Kindergarten ACS was the main exposure variable and fifth-grade BMI z-score was the main outcome measure. Covariates included (1) neighborhood safety and BMI z-score in kindergarten and (2) demographics (i.e., age, gender, race/ethnicity, socioeconomic status, single- vs. two-parent households, region of country, and urbanicity in fifth grade). Three interactions were included: school travel*neighborhood safety; school travel*BMI z-score (kindergarten); and school travel*socioeconomic status. Analysis of covariance accounted for the complex sampling design. Kindergarten ACS was associated with lower BMI z-score in fifth grade. The interaction of school travel*neighborhood safety indicated that children from less-safe neighborhoods who did ACS in kindergarten had a lower fifth-grade BMI z-score (p < 0.05) than their peers who did not do ACS in kindergarten (i.e., in terms of BMI, this difference was - 0.49 kg/m2 for children of average height in less-safe neighborhoods). Among children from less-safe neighborhoods, kindergarten ACS independently predicted lower BMI z-score in fifth grade among a national US cohort. Interventions and policies to increase ACS among young children, especially from unsafe neighborhoods, are warranted and should address parents' safety concerns.