Objectives: Few social ecological studies have considered the joint effects of intrapersonal and environmental influences on physical activity. This study investigated the interaction of self-efficacy and perceived neighborhood walkability in predicting neighborhood-based physical activity and how this relationship varied by gender and body mass index. Methods: Data were derived from a cross-sectional investigation of environmental and psychosocial correlates of physical activity among adults (n = 585). Participants completed a detailed 7-day physical activity log booklet, along with a questionnaire that included measures of neighborhood walkability, self-efficacy, and several sociodemographic items. Factorial analysis of variance tests were used to examine the main effects of and interaction between walkability and self-efficacy. Results: In predicting neighborhood-based physical activity, significant interactions were observed between self-efficacy and neighborhood walkability for females (but not for males) and for overweight/obese participants (but not for healthy weight individuals). Women and overweight/obese individuals with low self-efficacy demonstrated substantially greater physical activity when living in a high walkable neighborhood. Conclusions: Physical activity research and promotion efforts should take into account both environmental and personal factors and the interrelationships between them that influence active living.
Keywords: built environment, active living, social ecological models