Effect of Planning and Barrier Self-efficacy on Intention-Behavior Relationships

Regular physical exercise has been advocated as a key factor of a healthy lifestyle. Despite the various health benefits of engaging in exercise, many people continue to have a sedentary lifestyle. It is imperative, therefore, to identify a good model of predicting exercise behavior in order to introduce effective interventions. Theory of Planned Behavior (TPB. Ajzen, 1988) is the most effective model to predict intention-behavior process. However, it shows limitations in prediction and intervention of exercise behavior. The purpose of this study was to introduce new predictors based on TPB to improve the prediction of behavior. Study 1 and Study 2 were designed to test new models. Totally 350 collegiate students (168 males and 182 females) from two colleges in Anhui province were invited to participate in questionnaire investigations. Behavior planning and barrier self-efficacy was added to TPB as predictive variables and several alternative models were proposed based on available theories. Structural equation modeling was used to get goodness of fit for proposed models and to select the best model in term of goodness of fit. The result indicated that planning worked as mediator between exercise intention and exercise behavior, and improved prediction of exercise intention and exercise behavior. Barrier self-efficacy, working as a moderator, made contribution in better explanation and prediction of exercise behavior when it was added to the TPB model. After theoretical construct was verified by Study 1 and Study 2, Study 3 further investigated the effect of planning and barrier self-efficacy on improving exercise behavior. One hundred and sixteen university students (54 males and 62 females) were invited to participate in a quasi-experiment. Testing time was taken as a within-group variable and intervention method (planning group vs. barrier self-efficacy group) was taken as a between-group variable. The result of GLM-Repeated Measure in SPSS indicated that both planning and barrier self-efficacy improved the exercise behavior. However, there was no significant difference between the effect of planning and the effect of barrier self-efficacy. It was concluded that an individual's transforming process from exercise intension to exercise behavior was mediated by his/her exercise planning, and moderated by his/her barrier self-efficacy of exercise. Meanwhile the intervention on an individual's exercise planning and barrier self-efficacy might facilitate his/her exercise behavior.