Models of Behaviour Change in a Cardiac Rehabilitation Sample

Abstract

Background: The aim of this study was to examine exercise and relaxation in cardiac rehabilitation patients with the Theory of Planned Behaviour (Ajzen, 1991) and Temporal Self-Regulation Theory (Hall and Fong, 2007). Methods: Design: longitudinal; 6 months follow-up. Participants: cardiac rehabilitation inpatients with acute ischemic heart disease aged 65 or below. N=302, 278 (75%) males, mean age 55.61 (SD=7.31). Measures: self-report questionnaire about the variables of the theories. Three versions of TPB and two versions of TST were tested using path analyses. Findings: TPB explained 4–9% of variance in exercise and 14–15% in relaxation. TST explained 9–10% and 19–21% respectively. Model fits (exercise/relaxation): TPB complete model CFI .62/.82, RMSEA .18/.13; basic model: CFI .97/1.00, RMSEA .11/.00, third model CFI .99/.99, RMSEA .09/.05. TST original version CFI .94/.97, RMSEA .12/.09, TST modified model CFI .98/.99, RMSEA .09/.04. Discussion: The predictive powers of the models were low. TST had higher predictive power than TPB; relaxation was better predicted than exercise. The modified TST showed the best model fits. TST is a promising recent model.