Appropriate exercise can reduce the side effects of breast cancer therapy while improving long-term survival.
Current medical opinion unanimously supports the use of exercise in breast cancer prevention (see post: “Exercise for breast cancer prevention“) and in breast cancer rehabilitation (see post: “Exercise for breast cancer rehabilitation“). Indeed, the available clinical research suggests that the potential benefits of exercise for prevention and rehabilitation are enormous, including a reduction in the risk of breast cancer death following diagnosis by 50-53% (compared to sedentary women; ref 1).
While exercise for breast cancer prevention can be relatively straightforward, exercise for breast cancer rehabilitation is more nuanced. Exercise programs for cancer patients need to take into consideration the patient-specific side effects of anticancer treatment.
Unintended and adverse side effects are common for most medical interventions (so common there is actually a name for it: “iatrogenic artifacts”), and this is particularly true for cancer treatment where tissue removal and destruction is the objective. Surgery, chemotherapy and radiation therapy often leave patients with a variety of side effects including: pain, fatigue, anemia, decreased range of motion, neuropathy (nerve irritation), scarring, lymphedema (chronic swelling), axillary web syndrome, nausea, depression, and a corresponding decrease in patient-reported quality of life. Exercise therapy has been shown to help alleviate most of these side effects, while also dramatically improving long term survival.
For breast cancer patients exercise should be prescribed with caution to reduce the possibility of exacerbating some of these side effects. In particular, women with lymphedema should wear a compression garment when doing upper body exercise, exercise should be modified for patients with excessive fatigue or physical deconditioning, and exercise may also need to be modified to suit patient-specific restrictions in range of motion. Exercise need not only be designed to avoid exacerbating these conditions, but should also be utilized to encourage improvement in these areas.
Keeping in mind the above caveats, here is some general advice for women with breast cancer:
- Select a suitable exercise program. Walking and cycling are commonly used for rehabilitation and can be effective for treating fatigue, muscle deconditioning and depression. However, an optimal program would incorporate resistance training and stretching to improve upper body strength and range of motion.
- Exercise at an appropriate intensity. Intensity depends on your level of fitness and health status, but should be kept between 60% and 80% of your max heart rate (50% and 75% of your VO2peak). The Borg scale can be helpful for selecting a suitable intensity level (Table 1). You should try to achieve a level of exertion within the range of 11-14.
- Exercise for an appropriate duration. Your goal should be to achieve 30-45 minutes of continuous exercise. This is not always possible, in particular for patients at the start of their rehabilitation, patients with significant deconditioning, and older patients. If this applies to you, a more realistic goal may be 20-30 minutes of continuous exercise. An effective alternate strategy is to employ a circuit training or intermittent approach where you either cycle between activities, or take small breaks. For example, for running, walking or cycling activities this could take the form of a 10:1 split: 10 minutes activity followed by 1 minute of rest before resuming activity again.
- Exercise at an appropriate frequency. Your goal should be to exercise 3-5 times per week, for a total of about 150 minutes of activity per week.
For exercise advice that is patient-specific, it is necessary to speak with a cancer rehabilitation specialist. Often a single learning session is sufficient to set you on the optimal path of recovery, perhaps with intermittent follow-up sessions to help progress your exercise regimen.
- Volaklis K.A., Halle M., Tokmakidis S.P. Exercise in the prevention and rehabilitation of breast cancer. Wien Klin Wochenschr. 2013 May 8.