Effects of a combined aerobic and resistance exercise program in breast cancer survivors: a randomized controlled trial

Abstract

Few randomized controlled trials have examined the effects of combined aerobic and resistance training in breast cancer survivors soon after completing adjuvant therapy. Breast cancer survivors (N=58) within 2 years of completing adjuvant therapy were randomly assigned to an immediate exercise group (IEG; n=29) or a delayed exercise group (DEG; n=29). The IEG completed 12 weeks of supervised aerobic and resistance exercise, three times per week. The DEG completed the program during the next 12 weeks. Participants completed patient-rated outcomes at baseline, 6, 12, 18 and 24 weeks. The primary endpoint was overall quality of life (QoL) measured by the Functional Assessment of Cancer Therapy-Breast scale. Secondary endpoints were fatigue, social physique anxiety, and physical fitness. Follow-up data was obtained on 97% of participants and exercise adherence was 61.3%. Repeated measures analyses of variance revealed a significant group by time interaction for overall QoL (P<0.001). Specifically, QoL increased in the IEG from baseline to 12 weeks by 20.8 points compared to a decrease in the DEG of 5.3 points (mean group difference=26.1; 95% CI=18.3-32.7; P<0.001). From 12 to 24 weeks, QoL increased in the DEG by 29.5 points compared to an increase of 6.5 points in the IEG (mean group difference=23.0; 95% CI=16.3-29.1; P<0.001). Similar results were obtained for the secondary endpoints. Combined aerobic and resistance exercise soon after the completion of breast cancer therapy produces large and rapid improvements in health-related outcomes.