Stages of Change, Self-Efficacy, and the Adoption of Vigorous Exercise: A Prospective Analysis

Abstract
Components of the transtheoretical model of change were examined in a prospective study of the adoption of vigorous exercise in adults. Respondents to a random mail survey were resurveyed 2 years later. Those who reported no vigorous exercise at baseline were classified as either contemplators (n = 213) or precontemplators (n = 188). Contemplators had higher baseline self-efficacy scores than precontemplators (p < .001). In multivariate analyses, baseline stage of change was a significant predictor (p < .0005) of later adoption of vigorous exercise, even after controlling for differences in age, gender, and self-efficacy. During the first 6 months postbaseline, contemplators were nearly twice as likely as precontemplators to progress to the stage of action (46% vs. 24%), and four times more likely to progress to the stage of maintenance (25% vs. 6%). Use of the transtheoretical model in the study of exercise was supported in this prospective examination of exercise in a community sample.