Testing the requirements of stages of physical activity among adults: The comparative effectiveness of stage-matched, mismatched, standard care, and control interventions

We tested the comparative efficacy of 4 interventions to increase the physical activity behavior of college personnel randomly assigned to one condition (N = 196, 74% female, M age = 43.4 years) for 16 weeks. Stage-matched and mismatched interventions were developed based on the stages of change from the Transtheoretical Model and were contrasted with standard care (action-oriented) and control interventions to test the requirements of a true stage behavior Repeated measures of multivariate analyses of covariance indicated that the stage-matched and standard care interventions resulted in greater levels of both total and lifestyle physical activity compared with the mismatched and control interventions. The results supported the requirements of a stage behavior as defined by Weinstein, Rothman, and Sutton (1) and the superiority of the stage-matched intervention versus the mismatched intervention. However, the standard care intervention performed as well as the matched intervention, suggesting the need for further investigation. The results are discussed with respect to the high proportion of individuals in the action-oriented stages and previous research findings in the smoking literature.