Associations between Walkability and Youth Obesity: Differences by Urbanicity

Abstract

Background: Attributes of the built environment, such as neighborhood walkability, have been linked to increased physical activity and reduced obesity risk. This relationship, however, has primarily been documented in adults; less is known about neighborhood walkability and youth obesity, as limited prior research has produced mixed findings. The purpose of this study was to examine the association between neighborhood walkability and youth obesity, including differences by urbanicity. Methods: Data were collected in 2013 from youth aged 7-14 years (n = 13,469) in a Southeastern county school district. Height and weight were objectively measured and utilized to calculate body mass index (BMI) z-scores. Youth demographic characteristics and addresses were obtained, and a Walk Score® was gathered for each youth's home address. Multilevel linear regression analysis, accounting for nesting within census block groups, was conducted to examine the association between Walk Score and BMI z-score and to test for the moderating effect of urbanicity. Separate multilevel analyses examined Walk Score and BMI z-score among urban, urban-rural mixed, and rural youth subsamples. Results: Overall, as Walk Score increased, youth BMI z-score decreased. Walk Score was positively associated with BMI z-score among urban youth and negatively associated with BMI z-score among rural youth; no relationship was observed between Walk Score and youth in urban-rural mixed areas. Conclusions: Neighborhood walkability may impact youth differently across geographic areas. Further study is warranted about how youth utilize a walkable environment and mechanisms through which walkability influences youth physical activity and obesity risk.