Background: Few studies have examined the long-term adherence to a yearlong exercise intervention among postmenopausal women. We examined the patterns of adherence to a yearlong exercise intervention and the influence of demographic, physiologic, and psychosocial variables on patterns of adherence among 173 sedentary, overweight, postmenopausal women.
Methods: We collected demographic, physical activity (PA), physiologic, psychosocial, and medical history information at baseline and 12 months. The exercise prescription consisted of at least 45 min of moderate-intensity exercise 5 days/week for 12 months. We calculated several adherence variables. Associations between baseline variables and adherence levels were assessed in bivariate analyses and in multiple regression models.
Results: Women randomized to the exercise group (N = 87) participated in moderate-intensity sports or recreational PA on 3.7 +/- 1.4 days/week (79% of the prescribed 5 days/week) for 171 +/- 88 min/week (87% of the prescribed 225 min/week) over the yearlong trial period. Sixty-eight percent of the exercisers had a yearlong average PA level exceeding the national recommendation of 150 min/week. Being in the preparation stage vs. the contemplation stage of the transtheoretical model and a history of participating in any sports or recreational PA were significant predictors of adherence.
Conclusions: Our findings provide important information for the design of future PA interventions and health promotion programs.