Exercise manages fatigue during breast cancer treatment: a randomized controlled trial.

Fatigue is the most prevalent and debilitating symptom experienced by breast cancer patients receiving adjuvant chemotherapy or radiation therapy and few evidence-based treatments are available to manage this distressing side-effect. The purpose of this multi-institutional randomized controlled trial was to determine the effects of exercise on fatigue levels during treatment for breast cancer. Sedentary women (N=119) with Stage 0-III breast cancer receiving outpatient adjuvant chemotherapy or radiation therapy were randomized to a home-based moderate-intensity walking exercise program or to usual care for the duration of their cancer treatment. Of participants randomized to exercise, 72% adhered to the exercise prescription; 61% of the usual care group adhered. The intention-to-treat analysis revealed no group differences in part because of a dilution of treatment effect as 39% of the usual care group exercised and 28% of the exercise group did not. When exercise participation was considered using the data analysis method of instrumental variables with principal stratification, a clinically important and statistically significant (p=0.03) effect of exercise on pretest-to-posttest change in fatigue levels was demonstrated. Adherence to a home-based moderate-intensity walking exercise program may effectively mitigate the high levels of fatigue prevalent during cancer treatment.

Adherence to moderate-intensity exercise during breast cancer therapy.

PURPOSE: The aims of this pilot study were the following: 1) to examine patterns of adherence to a brisk walking program in women receiving adjuvant chemotherapy or radiation therapy for newly diagnosed breast cancer using a prospective, randomized, controlled experimental design; 2) to examine the influence of disease symptoms and treatment side effects on exercise levels; and 3) to suggest methods that may improve future clinical trials of moderate-intensity exercise in similar populations. DESCRIPTION OF STUDY: Fifty-two patients with newly diagnosed breast cancer were randomly assigned to one of two treatment arms: usual care or usual care plus exercise. Those assigned to the exercise group received a standardized, self-administered, home-based brisk walking intervention in addition to usual care. Each day subjects completed self-report diary forms that elicited information about activity levels, and the occurrence of symptoms and side effects during cancer treatment. RESULTS: Analyses of self-reported daily activity levels revealed a diffusion of treatment effect. Fifty percent of the usual-care group reported maintaining or increasing their physical activity to a moderate-intensity level, while 33% of the exercise group did not exercise at the prescribed levels. Analyses of self-reported disease symptoms and treatment side effects did not reveal clinically meaningful differences between the two groups. CLINICAL IMPLICATIONS: The results of this study suggest that women who exercised regularly before receiving a breast cancer diagnosis attempted to maintain their exercise programs. Women who lead sedentary lifestyles may benefit from a structured exercise program that includes information and support related to exercise adherence strategies.