Exercise may beat fatigue in prostate cancer

Staying active through moderate walking may help prevent fatigue in men undergoing radiation therapy for prostate cancer, a UK study shows.

Cancer patients commonly develop fatigue as the stress of the illness and the physical effects of treatment take their toll. It's common for patients undergoing treatment to be told to take it easy, and some may self-impose limits on their daily activities, according to the study's lead author Dr. Phyllis M. Windsor.

But in her team's study of 66 men with cancer confined to the prostate gland, those who were physically active during their month of radiation treatment showed no substantial increase in fatigue. The same was not true of patients in the non-exercising "control" group, according to findings published in the August issue of the journal Cancer.

The findings are in line with research with women undergoing radiation and chemotherapy for breast cancer, noted Windsor, a cancer specialist at Ninewells Hospital in Dundee, Scotland. It's thought, she told Reuters Health, that such results "potentially apply to all groups of patients with cancer."

While rest may be the intuitive response to fatigue, too much inactivity can make the problem worse. Long periods of rest, Windsor said, may de-condition muscles and roll back a person's capacity for exercise, making even routine daily tasks tough to tackle.

Exercise, on the other hand, keeps muscles conditioned, so that everyday activities require less effort and are less taxing on the body. In addition, Windsor pointed out, research suggests that exercise combats depression, which can alter patients' perceptions of fatigue.

For the current study, the researchers randomly assigned 66 men with localized prostate cancer to either an exercise group or a control group. The exercisers walked at a moderate pace for 30 minutes, three days per week; patients in the control group were not discouraged from performing their usual activities, but were told to rest if they became tired.

After four weeks of radiation therapy, men in the control group were had greater fatigue than they did before treatment; and one month later, these patients were still showing signs of weariness.

In contrast, exercisers showed no significant increase in fatigue at any point during the study, according to the researchers.

Windsor said she and her colleagues are planning a larger study to see if walking or, for patients who cannot walk, chair-based exercises can counter fatigue in patients with a range of cancers, including prostate, cervical, uterine, bladder and kidney cancers.

SOURCE: Cancer, August 2004.