EXERCISE AND THE MANAGEMENT OF CANCER

Exercise in the treatment of cancer

Exercise is attracting increasing attention as a treatment for cancers. Regular exercise can reduce the recurrence of some cancers after treatment with drugs, radiation, and/or surgery – and also prolong life. In one study of breast cancer, exercise treatment was associated with double the chance of survival over eight years and two-thirds the chance of recurrence.

The mechanisms through which exercise exerts its antitumor activity are still poorly understood but may be related to a direct effect on tumor cells or to an enhancement of immune function. It is believed that exercise stimulates the production of the immune system’s cytotoxic T cells, which are white blood cells specialized in killing cancer cells.

Exercise in the rehabilitation of cancer 

Cancer treatment causes reduced physical function and impaired quality of life. These negative effects result from most anti-cancer treatments such as surgery, radiation, hormonal treatment, and other targeted therapies. Exercise can be an extremely effective antidote to these ill effects. Some of the benefits include improved quality of life, increased cardiorespiratory fitness, better physical functioning, and less fatigue.

A meta-analysis of trials of exercise treatment in a wide variety of cancer types concluded that such treatment led to improvements in quality of life and fitness both during and after treatment. It has been proposed that physical training should be a part of cancer rehabilitation to facilitate activities and participation in daily life.  The intensity, frequency, and duration of exercise should be similar to the usual Department of Health recommendations. Some of the positive effects of exercise interventions are more pronounced with moderate or vigorous-intensity than with mild-intensity exercise programs.

There is no certainty that one form of exercise is better than any other in cancer patients. Running, brisk walking, cycling, weight lifting, bodyweight or elastic band exercises have all been tried with similar benefits.

Community-based activities may have greater long-term effects. Although most people with cancer identify physical, mental, and social benefits from exercising, cancer survivors have difficulty maintaining exercise after a supervised hospital-based program. Making exercise a part of daily life should help them to continue to perform it.

Prehabilitation

Prehabilitation involves interventions aimed at improving patients’ health before an anticipated upcoming physiologic stressor so that they are better able to withstand that stress. Prehabilitation emerged as a way to prepare soldiers for battle in the second world war. A study published in 1946 in the British Medical Journal, entitled Prehabilitation, Rehabilitation, and Revocation in the Army, described an experiment in which “good food, lodging, hygiene, and recreation combined with controlled physical training and education” for a period of around two months was found to improve the health ratings of 85% of the 12 000 men who participated.

Nowadays prehabilitation is used to prepare patients for major surgery. The idea is that the fitter the individual the better he or she is to cope with the ill effects of such operations. This may be particularly important for those who are most vulnerable. “Identifying high-risk patients at the earliest possible stage and increasing their physiological reserve prior to surgery is a promising approach that seems to result in remarkable improvements for older patients.” Exercise pre-surgery seems substantially to improve physical and pulmonary function, which are both factors associated with improved ability to undergo surgery while reducing post-surgery complications.

This particularly applies to cancer patients. Physical training increases physical training and resilience in preparation for cancer treatments all of which can be weakening and debilitating.  As an example, lung cancer patients undergoing surgery are usually left physically deconditioned and with functional deficits. Pre-operative exercise interventions improve pulmonary and physical function before and after lung resection and also reduce the complications of surgery.

Importantly, small changes in cardiopulmonary fitness may have a large impact on patients who are frail, including elderly patients with multiple comorbidities.

PS
Should you wear a mask while exercising?

A study reported in the  International Journal of Environmental Research and Public Health looked at the exercise tolerance of a group of physically active and healthy men and women¹. They were exercised maximally on a bicycle ergometer. The team assessed the participants, who did the test three times each, once wearing a surgical face mask, once wearing a three-layer cloth face mask, and once with no face mask. The team recorded the participants’ blood oxygen levels and muscle oxygen levels throughout the test using non-invasive measurement tools. There was no difference between the three tests for exercise performance nor for blood and muscle oxygenation.

So the answer is a qualified yes. Wearing a mask will reduce the possibility of transmitting the virus – but it can be quite uncomfortable when exercising and it doesn’t half steam up your specs.

1. DOI: 10.3390/ijerph17218110