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

Abstract

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.

Figures

Figure 1. Mediational Chain Model

(a) Direct effect of time 1 variables on time 2 variables. (b) Direct effects plus indirect effects of Time 1 and Time 2 variables on Time 2 mediators. (c) Direct and indirect effects from (b) plus indirect effects of Time 1 and Time 2 variables on Time 2 outcomes. (d) Confirmed mediational relationships of Time 1 and Time 2 variables on Time 2 outcomes.