Fitness and cancer: Can you do too much exercise?

Exercise is not something many oncologists discuss with their patients, and many cancer patients are reluctant to exercise, particularly if they didn't engage in regular exercise before they developed their condition. It used to be thought that exercising during cancer treatment would leave you feeling exhausted, and without the energy that you needed to continue fighting your cancer battle. Exhaustion is not something many people are prepared to risk when their treatment has already left them feeling fatigued or experiencing nausea and lethargy, a common side effect of chemotherapy.

However the American Cancer Association now recommends that all cancer patients enjoy regular exercise; the concern about any damage caused by exercise during treatment has been proven to be unfounded. According to the Mayo Clinic, it has even been found that exercising during your chemotherapy treatment can help to minimize its negative side effects.

The benefits of exercise

If you feel reluctant to exercise while you are dealing with cancer then you may find it helpful to focus on some of the benefits of regular exercise to cancer patients. Exercising regularly during treatment can significantly reduce your risk of cancer recurrence, and can also provide you with a boost of energy that will help to minimize the side effects of conventional cancer treatment.

For these reasons, many experts now believe exercise should be prescribed as a standard part of cancer care, with Ciaran Devane, chief executive of Macmillan Cancer Support, stating “Cancer patients would be shocked if they knew just how much of a benefit physical activity could have on their recovery and long-term health.”

That doesn't mean you need to exercise every day if you don't feel physically able. Whether you are in the middle of your cancer treatment or not, it is possible to do too much exercise and some cancer patients risk developing an unhealthy relationship with the exercise by focusing too much on it, and not listening to their body when it is telling them to stop.

Over-exercising will leave you at increased risk of suffering from muscle strain, broken bone and other forms of overuse injury, and these ailments are likely to heal much slower than they might usually during your cancer treatment because your immune system will already be weakened, so it is important to listen to your body, exercise as often as you are able but avoid doing too much, and stop as soon as you feel you've had enough.

Be risk aware

Of course the type of exercise you are able to enjoy, and the amount of regular exercise you can undertake is likely to depend on the type of cancer you have and its severity. For this reason, we recommend that you consult your physician before you embark on any new exercise program.

Lifting weights might be a great form of exercise for you if you have a melanoma on your leg, for example, whilst someone who has recently had surgery for their breast cancer will be advised to avoid weight lifting or other forms of resistance training involving their upper body. This is because individuals who have recently undergone breast cancer surgery, may be at increased risk of developing lymphedema: this is the swelling of the soft tissues in the arm, hand, trunk, or breast that may be accompanied by numbness, discomfort, and sometimes infection, and is something that should be avoided wherever possible in breast cancer patients.

Some doctors and the breast cancer patients themselves are worried that strength training during the course of treatment could trigger the onset of lymphedema, and it is understandable why this leaves many women feeling reluctant to exercise.It is important that you are aware of the risks certain exercise types could pose to your body during your treatment, that you discuss these with your physician, and that you change your exercise routine accordingly. However there is no form of cancer that should leave you unable to exercise altogether, so whatever you find you are able to do, you should get up, move your body, and do it.

It is important that you are aware of the risks certain exercise types could pose to your body during your treatment, that you discuss these with your physician, and that you change your exercise routine accordingly. However there is no form of cancer that should leave you unable to exercise altogether, so whatever you find you are able to do, you should get up, move your body, and do it.

— Helen Bennett