Exercise programs for cancer patients during chemo- and radiotherapy

Rehabilitation Oncology, 2000 by Dimeo, Fernando

Fatigue is a frequent and severe problem of cancer patients undergoing treatment. Several studies have reported that more than 60% of cancer patients experience substantial fatigue during chemotherapy; moreover, about 30% of patients are not able to carry out usual daily activities after concluding therapy due to this symptom.

Fatigue is often considered to be an inevitable result of disease and therapy. Side-effects of oncological treatment such as anaemia, corticoid-induced myophathy, and cardiotoxicity can severely affect the patient's functional ability. To reduce the intensity of fatigue, patients are frequently advised to downregulate their daily activities and to avoid exertion. However, the result of this recommendation can be paradoxical. Patients reduce their activity to a minimum; therefore, due to the lack of exercise, they lose muscle mass and cardiorespiratory fitness. Hence, activities requiring physical effort become increasingly strenuous. A vicious circle is created in which patients avoid exertion due to rapid exhaustion and physical performance is reduced by lack of exercise. This mechanism has been postulated as an etiologic factor for the long-lasting fatigue frequently observed in cancer patients.

A new approach is therefore required in order to implement successful treatment of fatigue. Patients do not need rest but physical exercise, in order to restore their normal physical performance. Exercise results in a substantial increase of muscle mass and stamina. Therefore, daily activities are less strenuous and patients find it easier to cope with them. Based on this, interest has developed on the effects of exercise as therapy for cancer-related loss of physical performance and fatigue.

A growing body of evidence suggest that endurance training is an effective method to reduce chemotherapy and disease-induced fatigue.2,3,5,6 In pilot studies with patients after allogenous bonemarrow transplantation,4 or high-dosed chemotherapy and autologous peripheral stem-cell transplantation,4 a 6-week aerobic exercise program consisting of walking for 30 minutes daily on a treadmill following an interval-training program, yielded a significant improvement of physical performance and a reduction of fatigue. Further studies with patients after highdosed chemotherapy and autologous stem-cell transplantation have shown that endurance training can reduce the chemotherapy-related loss of physical performance in 30%.2 Furthermore, physical activity can also improve mood and reduce mental stress of cancer patients undergoing chemotherapy. Self-esteem and independence of patients increase as their functional ability improves. Finally, several reports have shown that an endurance training program does not result in a higher incidence of chemotherapy-related complications.

This evidence shows that aerobic exercise and physical activity can be effective therapies for cancer fatigue. Current studies evaluate the effects of endurance training in cancer patients undergoing conventional chemotherapy or after surgery.

REFERENCES

1. Dimeo F, Bertz H, Finke J, Fetscher S, Mertelsmann R, Keul J. An aerobic exercise program for patients with haematological malignancies after bone marrow transplantation. Bone Marrow Transplant. 1996;18:11571160.

2. Dimeo F, Fetscher S, Lange W, Merfelsmann R, Keul J. Effects of aerobic exercise on the physical performance and incidence of treatment-related complications after high-dose chemotherapy. Blood. 1997;90:3390-3394.

3. Dimeo F, Rumberger BG, Keul J. Aerobic exercise as therapy for cancer fatigue. Med Sci Sports Exerc. 1998;30:475-478.

4. Dimeo FC, Tilmann MH, Bertz H, Kanz L, Mertelsmann R,

Keul J. Aerobic exercise in the rehabilitation of cancer patients after high dose chemotherapy and autologous peripheral stem cell transplantation. Cancer. 1997;79:1717-1722.

5. MacVicar MG, Winningham ML, Nickel JL. Effects of aerobic interval training on cancer patients' functional capacity. Nurs Res. 1989;38:348-351.

6. Winningham ML. The role of exercise in cancer therapy. In: Watson R, Eisinger M, eds. Exercise and Disease. Boca Raton: CRC Press; 1992:63-70.

Fernando Dimeo, MD

Dept. of Sports Medicine

Freie Universitaet Berlin, Germany