Mediating effects of group cohesion on physical activity and diet in women of color: health is power.

Purpose: To determine the effects and mediating factors of a physical activity (PA) or vegetable and fruit (VF) group cohesion intervention.

Design: Longitudinal design.

Setting: Harris County and Travis County, Texas.

Participants: Community-dwelling African-American and Hispanic or Latina women.

Intervention: Three hundred ten women were randomized to a PA (n  =  204) or VF (n  =  106) intervention group. Women met in groups six times over the course of 6 months and were exposed to a group cohesion intervention to promote walking or to increase VF consumption.

Measures: Women completed the International PA Questionnaire, National Cancer Institute VF and fat screeners, PA Group Environment Questionnaire, and 7-day accelerometer protocol at baseline and post-intervention.

Analyses: The direct and mediated effects of the intervention on outcomes were evaluated using a mediational chain model, controlling for baseline values and covariates using path analysis.

Results: Women were middle aged (mean  =  44.4 years) and overweight or obese (mean body mass index  =  34.0 kg/m(2)). PA increased and fat consumption decreased for both groups, whereas VF consumption increased for women in VF group only (all p < .05). Increased task cohesion led to hypothesized increases in psychosocial factors in the PA group but not to behavioral changes.

Conclusions: Group cohesion interventions may have psychological and physical health benefits for African-American and Hispanic or Latina women, but refinement of measures and intervention delivery is needed to determine whether hypothesized mediational pathways are valid.