Stages of Change in Physical Exercise: A Test of Stage Discrimination and Nonlinearity.

Objectives: To investigate the utility of the protection motivation theory (PMT), social-cognitive theory (SCT) and transtheoretical model's (TTM) processes of change (POC) by (1) discriminating between TTM's stages with planned comparisons and (2) examining higher-ordered trends across stages. Methods: 1582 individuals were included in the analyses that tested severity, vulnerability, response-efficacy, self-efficacy, POC, pros and cons, social and environmental support. Results: The findings provide evidence for the utility of the PMT and TTM's POC for stage discrimination; stage discontinuity patterns are supported. Conclusions: Promotion of health behavior should target stage-specific variables, such as threat appraisals for early stage movements. [ABSTRACT FROM AUTHOR]