|Zoellner, Jamie -|
|Tussing-Humphreys, Lisa -|
Submitted to: American Journal of Health Promotion
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 5, 2013
Publication Date: January 1, 2014
Citation: Thomson, J.L., Zoellner, J.M., Tussing-Humphreys, L.M. 2014. Psychosocial predictors of diet and physical activity in African- Amercians: results from the Delta Body and Soul effectiveness trial, 2010-2011. American Journal of Health Promotion. 28(3):e81-e91. Interpretive Summary: Consumption levels are below recommendations for fruit, vegetables, and whole grains, and above recommended levels for sugar-sweetened beverages in the US, particularly in African Americans. Physical activity (PA) levels are also below recommendations in the US with African Americans less likely to meet guidelines as compared to whites. Eating nutritious foods and getting regular exercise are necessary for optimal health, hence determining how to change such behaviors is important. Three of the more common theoretical concepts that may help to explain how individuals change their health behaviors include self-efficacy, or the confidence in one’s abilities and skills to engage in certain behaviors; social support, or the physical and emotional comfort given by family, friends, and others; and decisional balance, or the examination and weighing of both negative and positive aspects of a behavior. Data used in these analyses were collected during a 6-month, church-based, diet and physical activity intervention conducted in southern, African American adults. Relationships between changes in these behavioral determinants and changes in diet and physical activity were explored using statistical models. While the intervention was effective in improving diet quality and increasing physical activity of the participants, only the dietary changes could be explained by improvements in the behavioral determinants. Further research is needed to determine which behavioral determinants are most important in affecting health behavior change, particularly in faith-based interventions.
Technical Abstract: The purpose of this study was to examine associations among psychosocial constructs of behavior change and post-intervention changes in diet and physical activity (PA). The study design was quasi-experimental with cluster (church) treatment assignment. The study setting was churches (n=8) in a rural, southern region of the United States. Subjects included 403 African American adults participating in the Delta Body and Soul study. The study was a 6-month diet and PA intervention consisting of monthly didactic educational sessions with specific emphasis on increasing consumption of fruits, vegetables, and whole grains, and decreasing consumption of added sugars. Self-directed PA was promoted throughout the intervention. Data were collected using validated surveys for all dietary, PA, and psychosocial measures. Secondary analysis using generalized linear mixed models to test for significant intervention effects on psychosocial constructs and for significant associations between changes in psychosocial constructs and changes in diet and PA outcomes after controlling for covariates was used to address the research questions. Results indicated intervention effects were apparent for several dietary psychosocial constructs (improvements ranging from 0.5 to 2.0 points), but only one PA construct (decisional balance for exercise). Changes in psychosocial constructs, including self-efficacy, social support, and decisional balance, were significant predictors of dietary outcome changes (model coefficients ranging from 0.03 to 0.42), but not PA changes. Understanding which psychosocial constructs predict improvements in dietary and PA behaviors helps inform theoretical mechanisms of action and identify social and behavioral processes to target in faith-based interventions.