Young-McCaughan, S., & Arzola, S.M. (2007). Exercise intervention research for patients with cancer on treatment. Seminars in Oncology Nursing, 23, 264–274.

To review research and guidelines regarding the use and potential benefits of exercise for patients with cancer undergoing treatment

Databases searched were Ovid, MEDLINE, and CINAHL (1980–2007).

• Studies involved male and female patients with cancer undergoing treatments. The majority of studies involved women with breast cancer. Other cancers included prostate, colon, lung, stomach, endometrial, head and neck, lymphoma, multiple myeloma, and melanoma. Patients undergoing bone marrow or stem cell transplant also were represented.
• Most studies involved patients with stage I or II disease, and some studies involved patients with metastatic disease. In patients with metastatic disease, as high as two-thirds were able to complete a 12-week program.
• Most exercise intervention studies with patients with cancer followed the American College of Sports Medicine recommendations.  

Stage of Disease:

• Evidence suggests that, although most studies recruited from patient populations with early stage I or II disease, even patients with metastatic disease have been able to exercise successfully.
• Stage of disease may influence exercise program completion rates.  In one study, however, almost two-thirds of the participants with stage III or IV disease were able to complete the 12-week intervention study. Patients appear to be able to safely and successfully exercise.

Types of exercise programs:

Most studies involved aerobic exercise, 11 studies included strength training, and 8 studies examined a combination of aerobic with strength training. None evaluated flexibility exclusively. 

Outcomes:

Compared to controls, the exercise groups improved cardiovascular and muscular fitness, experienced less fatigue, and slept longer. Exercise has been shown to improve almost all aspects of physiologic and psychologic functioning, including immune status. Of all the measures affected, cancer fatigue was the most improved. Although cancer fatigue has been thought to prevent patients with cancer from exercising, evidence has demonstrated that those who exercise experience less fatigue.

Frequency, intensity and adherence to exercise programs:

Participants exercised anywhere from 3–7 days a week for 2–52 weeks, for 10–45 minutes per session at 50%–85% of heart rate reserve. Adherence to the exercise prescription of frequency, intensity, time, and type ranged from 66%–78%. Typically, subjects in control groups started their own exercise programs (39%), such that diffusion of treatment effects can be an issue.

Interest:

In 2005, 63% of 187 participants agreed to join an exercise study, whereas in 2003, only 19% agreed to participate. Many hospital, clinics, and health clubs now offer programs specifically for cancer survivors. 

Concerns:

Concerns about exercise when undergoing cancer treatment have included bone metastasis, cardiac toxicities of therapies, and lymphedema. However, studies have shown that

• Patients with bone metastasis in nonweight-bearing bones safely can exercise.
• Exercise programs have been successfully tested to increase exercise tolerance in childhood cancer survivors who have received therapies with cardiac toxicities (e.g., anthracyclines, high-dose chemotherapy). In view of the paucity of information, one recommendation might be no exercise. However, based on the benefits of exercises in other patients with congestive heart failure symptoms, another recommendation would be to exercise as tolerated, reducing exercise intensity for symptoms, such as unusual fatigue, muscular weakness, shortness of breath, dizziness, faintness, or other unusual symptoms. 
• Exercise has been blamed for exacerbating or triggering lymphedema, theoretically because of increased blood flow and increased metabolic waste that could trigger an increase lymphatic flow and load on an already compromised system.  However, at least three clinical trials of women with breast cancer have shown no increased risk for or exacerbation of LE from either aerobic or resistance exercise.  The recommendation is to start lymphedema patients with exercise slowly, gradually increasing the time and intensity of the exercise sessions.

Because of lack of research, the best mode of exercise for patients with cancer has not been determined. At the same time, no mode in any of the studies reviewed here have been determined to be harmful. Of all the nonpharmacologic interventions for cancer-related fatigue recommended by the National Comprehensive Cancer Network (NCCN), exercise has the strongest evidence.  Any exercise prescription should include the components of frequency, intensity, time, type, and progression.  Issues regarding exercise prescription in patients with cancer relate more to the treatment side effects than to the cancer itself.  Since recovery from cancer treatment is unpredictable and side effects are individual in nature, collaboration between experts in cancer care and experts in exercise physiology is essential. In general, however, frequency and duration goals should be met before intensity goals and progression should be slower and more gradual for the deconditioned patient or those who are experiencing severe side effects of treatment.

Nurses can encourage exercise as part of a patient’s therapy and guide the patient to a safe program.