Does protection motivation theory explain exercise intentions and behavior during home-based cardiac rehabilitation?

Objective: Home-based cardiac rehabilitation (CR) programs have been shown to be effective in increasing exercise capacity, which is a significant predictor of longevity for patients with heart disease. However, adherence to these programs has been problematic. Therefore, it is important to identify key theoretical correlates of exercise for these patients that can be used to inform the development of behavioral interventions to help tackle the adherence problem. The purpose of this study was to determine whether protection motivation theory (PMT) explained significant variation in exercise intentions and behavior in patients receiving home-based CR.

Methods: Patients (N = 76) completed a questionnaire that included PMT constructs at the beginning and midpoint (ie, 3 months) of the program and an exercise scale at 3 and 6 months (ie, at the end of the CR program).

Results: Path analyses showed that response efficacy was the sole predictor of 3-month (beta = .53) and 6-month (beta = .32) intentions. However, the indirect effect of baseline response efficacy on 3-month exercise behavior through intention was nonsignificant (beta = -.01), whereas it was significant (beta = .11) for 3-month response efficacy on 6-month exercise behavior. Self-efficacy significantly predicted 3-month (beta = .36) and 6-month (beta = .32) exercise behaviors, whereas 3-month intention significantly predicted 6-month exercise behavior (beta = .23).

Conclusions: Coping appraisal variables (ie, response efficacy and self-efficacy) are potentially useful in explaining exercise behavior during home-based CR.