Purpose: Cancer treatment-related fatigue is the most prevalent and distressing symptom of cancer therapy. Interventions to minimize fatigue are needed. The purpose of this study was to examine the relationship between exercise and fatigue over the first three cycles of chemotherapy in women receiving either cyclophosphamide, methotrexate, and fluorouracil (CMF) or doxorubicin and cyclophosphamide (AC) for breast cancer.
Methods: Seventy-two newly diagnosed women with breast cancer were instructed in a home-based moderate-intensity exercise intervention. Measures of functional ability, energy expenditure, and fatigue were obtained at baseline and posttest. Subjects maintained daily records of four types of fatigue, and exercise duration, intensity, and type.
Results: Exercise significantly reduced all four levels of fatigue (P < 0.01). As the duration of exercise increased, the intensity of fatigue declined (P < 0.01). There was a significant carry-over effect of exercise on fatigue, but the effect lasted only 1 d. The level of fatigue at study entry was not associated with number of days of exercise or amount of exercise a woman engaged in.
Conclusions: The impact of exercise on fatigue was significant and suggests the effectiveness of a low- to moderate-intensity regular exercise program in maintaining functional ability and reducing fatigue in women with breast cancer receiving chemotherapy.