Several studies suggest exercise may give an immune system boost to cancer survivors, but more research is needed to see if this translates into a lower risk of cancer recurrence.

Of the six studies reviewed, four showed that patients who followed a supervised exercise plan during or after cancer treatment had certain improvements in immune system function.

The majority of physicians are probably unaware of the benefits of exercise in cancer survivors. This is likely due to the fact that researchers have only recently begun to examine the utility of exercise.

The researchers found that in four studies, exercising patients showed some improvement in immune system function, including greater activity or better function in certain important immune cells. In addition, some exercisers showed better endurance, less decline in physical performance and greater muscle strength than patients who did not exercise.

Cancer 2002;94:539-551