This study examined the structure of the transtheoretical model (TM) in exercise behavior change among adults age 50–65 years (n = 583). The purpose was to examine the relationship between stage of change and the constructs of processes of change, self-efficacy, and decisional balance. The results showed that 5 of the 10 processes of change, self-efficacy, and both pros and cons make significant and unique contributions to discrimination between the stages. Specifically, the use of the processes of change was shown to fluctuate across the stages, self-efficacy was shown to increase from precontemplation to maintenance, and the balance between pros and cons was shown to change from precontemplation to maintenance. The similarity of these results to previous literature suggests that the process of behavior change hypothesized within the TM holds across different age groups and cultures. Several implications for intervention design and suggestions for further research are discussed.
Trish Gorely and Sandy Gordon are with the Department of Human Movement at the University of Western Australia, Nedlands, WA 6009, Australia.