Psychosocial constructs and postintervention changes in physical activity and dietary outcomes in a lifestyle intervention, HUB City Steps, 2010.

INTRODUCTION: Although modifications to dietary and physical activity (PA) behavior can reduce blood pressure, racial disparities in prevalence and control of hypertension persist. Psychosocial constructs (PSCs) of self-regulation, processes of change, and social support are associated with initiation and maintenance of PA in African Americans; which PSCs best predict lifestyle behavior changes is unclear. This study's objective was to examine relationships among PSC changes and postintervention changes in PA and dietary outcomes in a community-based, multicomponent lifestyle intervention.

METHODS: This study was a noncontrolled, pre/post experimental intervention conducted in a midsized, Southern US city in 2010. Primarily African American adults (n = 269) participated in a 6-month intervention consisting of motivational enhancement, social support, pedometer diary self-monitoring, and 5 education sessions. Outcome measures included pedometer-determined steps per day, fitness, dietary intake, and PSC measures. Generalized linear mixed models were used to test for postintervention changes in behavioral outcomes, identify predictors of PSC changes, and determine if PSC changes predicted changes in PA and diet.

RESULTS: Postintervention changes were apparent for 10 of 24 PSCs (P < .05). Processes of change components, including helping relationships, reinforcement management, and consciousness raising, were significant predictors of fitness change (P < .05).

CONCLUSION: This article is among the first to address how measures of several theoretical frameworks of behavior change influence changes in PA and dietary outcomes in a multicomponent, community-based, lifestyle intervention conducted with African American adults. Findings reported identify PSC factors on which health behavior interventions can focus.