Ethnicity and the theory of planned behavior in an exercise context: A mediation and moderation perspective

Objectives: Most college students fail to meet recommended exercise levels and ethnic disparities in participation are apparent. The present study examined the moderating and mediating relationships among ethnicity, the theory of planned behavior (TPB), and exercise, and identified common and ethnic-specific beliefs related to exercise. Method: College students completed a baseline TPB questionnaire and an exercise assessment at either two-week (n=237 blacks; n=176 whites) or two-month (n=280 blacks; n=273 whites) follow-ups. Design: One week and two month longitudinal designs. Results: Structural equation modeling showed that the TPB was invariant by ethnicity in both samples with affective attitudes and perceived behavioral control being significant predictors of intention, which in turn, significantly predicted exercise. Furthermore, analyses showed that the TPB had a small mediating effect on the ethnicity/exercise relationship in both samples. Finally, common and ethnic-specific beliefs were identified that varied by sample. Conclusion: The TPB is a useful framework to explain exercise behavior in black and white students; however, its ability to explain the ethnic disparity in exercise may be limited.