Social Context of Physical Activity and Weight Status in Working-Class Populations

BACKGROUND: Persistent disparities suggest that multiple aspects of social context may influence leisure-time physical activity levels and weight status in multiethnic, working-class populations. METHODS: Among participants in two randomized, controlled intervention trials (n = 1,969 in 10 health centers; n = 1545 in 26 manufacturing businesses) the authors used general linear mixed models to examine the relationship of variables posited by a social-contextual framework for behavior change with h/wk of self-reported leisure-time physical activity and with body mass index (BMI; weight [kg]/[height (m)2]) at baseline, adjusting for clustering within study site. RESULTS: Age, sex, race/ethnicity, and socioeconomic position were independently associated with leisure-time physical activity in both settings; multivariable models explained 15% of the variance in health centers and 11% in small businesses. Leisure-time physical activity and motivation to change lifestyle behaviors were inversely associated with BMI, adjusting for individual, interpersonal, and neighborhood factors. Models explained 12% of the variance in BMI in health centers and 10% in small businesses. CONCLUSIONS: A social-contextual framework highlights the contribution of social class and race/ethnicity in the variance in leisure-time physical activity and weight status but suggests other behavioral influences vary in multiethnic, working-class populations.