Using Self-Efficacy and Intention to Predict Exercise Compliance among Patients with Ischemic Heart Disease

There were three aims to the present study: (a) to test a social cognitive model based on self-efficacy and intention in predicting compliance to exercise in a Phase 2 cardiac rehabilitation (CR) program; (b) to examine temporal patterns of self-efficacy in an 18-week exercise CR program; and (c) to ascertain whether the social-cognitive variables act more as determinant or consequence of exercise behavior during the program. Forty-one participants (29 M, 12 F; mean age 63 ± 9 .81 yrs) with documented ischemic heart disease enrolled in an 18-week supervised walking-based Phase 2 CR exercise program. They completed scales assessing self-efficacy and intention at the beginning of the program (Time 1) and again at Weeks 7 (Time 2) and 13 (Time 3). Compliance behavior was assessed through daily attendance and exercise energy expenditure measures, via metabolic equivalents (ACSM Guidelines, 1995). Data provide general support for the social cognitive model. That is, positive and meaningful relationships were found among self-efficacy, intention, and objectively measured exercise behavior, explaining 16 to 59% of the variance. Results also showed that both task and barrier efficacy significantly improved during the early part of the exercise program and then leveled off during program termination. Finally, results suggest that social-cognitive variables act more as a determinant than a consequence of exercise behavior. The findings underscore the need for scale congruence between the measures of self-efficacy, intention, and objective measures of exercise behavior.