Abstract: | The present study investigated the role of social support provisions and efficacy cognitions in adherence to a prescribed exercise regimen. A generalized estimating equations approach was employed to estimate regression coefficients via an iterative weighted least squares algorithm. Findings indicated that when employed as time-varying covariates, the social provisions of reassurance of worth, attachment, and, to a lesser extent, guidance were significantly associated with intraindividual fluctuations in program adherence. Specifically, individuals with a greater sense of self-worth were more likely to adhere throughout the program, whereas the effects of subject's perceptions of greater attachment, although generally related to sustained adherence, fluctuated over time. Findings also suggest that individuals perceiving higher levels of guidance were less likely to adhere during the early and concluding stages of the exercise program. Although synchronous covariation existed between efficacy cognitions and attendance, self-efficacy was not predictive of intraindividual change in attendance over time. Results are discussed in regard to the importance of self-referent processes and social provisions in exercise adherence, and the utility of the proposed generalized estimating equations approach to the analysis of longitudinal data. |