Does Perceived Safety Modify the Effectiveness of a Walking-Group Intervention Designed to Promote Physical Activity?

PURPOSE: To examine whether perceived safety modified the effectiveness of the Walk Your Heart to Health (WYHH) intervention in promoting physical activity and reducing central adiposity in predominantly non-Latino black (henceforth black) and Latino communities.
DESIGN: Generalized estimation equations were used to assess modifying effects of perceived safety on the route and perceived neighborhood safety on (1) WYHH participation at 8 weeks and 32 weeks, (2) associations between participation and physical activity, and (3) associations between physical activity and central adiposity.
SETTING: Community-based and faith-based organizations in black and Latino communities. PARTICIPANTS: There were 603 adults, aged 18 years and older, who were predominantly black, Latino, and female. MEASURES: Participation and physical activity (piezoelectric pedometer) were measured at each walking session. Perceived safety on the route (questionnaire), perceived neighborhood safety (questionnaire), and waist circumference were measured at baseline, 8 weeks, and 32 weeks. ANALYSIS: Secondary analysis of repeated measures using generalized estimation equations.
RESULTS: Retention was 90% at 8 weeks and 64% at 32 weeks. Perceived safety on the route, but not perceived neighborhood safety, dampened participation at 8 weeks but not 32 weeks. Consistent participation in the intervention increased physical activity and reduced central adiposity irrespective of perceived safety on the walking route or perceived neighborhood safety.
CONCLUSION: Efforts to improve safety in conjunction with interventions focused on increasing physical activity can work toward improving physical activity for blacks and Latinos, leading to a myriad of improved health outcomes including reduced central adiposity.