Objective: To apply the constructs of the transtheoretical model (TTM) of change to understand physical activity among individuals with severe mental illness.
Method: Predictions of stages of change of physical activity and self-reported physical activity were investigated among 92 adults with severe mental illness, using cognitive and behavioral processes of change, self-efficacy, and perceived pros and cons of exercise as predictors.
Results: Separate logistic regression analyses for adjacent pairs of stages indicated that 33% of the variance was accounted for when predicting preparation versus action/maintenance stages, with behavioral processes making a significant unique contribution to prediction. A multiple-regression analysis was conducted to examine prediction of self-reported physical activity on the basis of all of the TTM measures, and the full model accounted for nearly 27% of the variance.
Conclusion: Results suggest that TTM constructs hold promise in understanding physical activity of people with severe mental illness with significant implications for clinical practice and future research.