Background: We previously reported no postintervention differences in quality of life and other psychosocial outcomes when comparing 12-month high versus moderate volume of aerobic exercise in postmenopausal women. Here, we report the 24-month follow-up for these outcomes. Methods: At 24-month follow-up, 333 out of 400 postmenopausal women were randomized to a year-long intervention of 150 (moderate) or 300 (high) minutes per week of aerobic exercise returned a battery of self-reported measures assessing quality of life, psychosocial outcomes, and sleep quality, also assessed at baseline and postintervention. Intention-to-treat analyses using linear models were conducted to determine the changes between baseline and 24-month follow-up. Results: No significant effects between moderate- and high-volume aerobic exercise groups were observed among any outcomes. There was some evidence of effect moderation by baseline body mass index in relation to quality of life, psychosocial outcomes, and sleep quality, where obese women benefitted from the moderate-volume exercise and nonobese women benefitted from the high-volume exercise prescription. Conclusion: Although high-volume aerobic exercise did not improve psychosocial outcomes when compared with moderate volume at the 24-month follow-up, we did observe potential effect of moderation between obese and nonobese women. Confirmation of these interactions is warranted in this population.
Farris, O’Reilly, and Friedenreich are with the Dept of Cancer Epidemiology and Prevention Research, CancerControl Alberta, Alberta Health Services, Calgary, Alberta, Canada. Courneya is with the Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada. Friedenreich is also with the Depts of Oncology and Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.