|Mendoza, Jason -|
|Watson, Kathy -|
|Nguyen, Nga -|
|Cerin, Ester -|
|Baranowski, Thomas -|
|Nicklas, Theresa -|
Submitted to: Journal of Physical Activity and Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 1, 2010
Publication Date: May 1, 2011
Citation: Mendoza, J.A., Watson, K., Nguyen, N., Cerin, E., Baranowski, T., Nicklas, T.A. 2011. Active commuting to school and association with physical activity and adiposity among US youth. Journal of Physical Activity and Health. 8(4):488-495. Interpretive Summary: Childhood obesity is a major public health problem in the US. Walking and bicycling to school (active commuting) has shown promise for increasing children’s physical activity and decreasing their risk for obesity. We investigated whether children’s active commuting was related to more physical activity and lower measures of obesity among a large national sample of US youth. With more active commuting, youth attained higher amounts of daily physical activity and had lower measures of obesity. Active commuting appears promising to help address the nation’s obesity epidemic.
Technical Abstract: Walking or bicycling to school, i.e. active commuting, has shown promise for improving physical activity and preventing obesity in youth. Our objectives were to examine, among US youth, whether active commuting was inversely associated with adiposity and positively associated with moderate-to vigorous physical activity (MVPA). We also examined whether MVPA mediated the relationships between active commuting and adiposity. Using data of participants aged 12-19 years from the US National Health and Nutrition Examination Survey 2003-2004 (n=789 unweighted), we constructed multiple linear regression models that controlled for dietary energy intake and socio-demographics. The main exposure variable was active commuting. The outcomes were BMI z-score, waist circumference, skinfolds and objectively measured MVPA. The product-of-coefficients method was used to test for mediation. Active commuting was inversely associated with BMI z-score (beta=-0.07, p=0.046) and skinfolds (beta=-0.06, p=0.029), and positively associated with overall daily (beta=0.12, p=0.024) and before- and after-school (beta=0.20, p<0.001) MVPA. Greater before- and after-school MVPA explained part of the relationship between active commuting and waist circumference (Sobel z=-1.98, p=0.048). Active commuting was associated with greater MVPA and lower measures of adiposity among US youth. Before- and after-school MVPA mediated the relationships between active commuting and waist circumference.