Men who took part in a regular exercise program had fewer precancerous changes to the colon lining than non-exercisers, a study shows -- and the more vigorous the exercise, the better the results.

While there is no surefire way to prevent colon cancer or a recurrence, lifestyle choices may lower your risk of colon cancer. Much of the new information echoes time-honored common sense: Eat a healthy diet high in fruits and vegetables, maintain an appropriate weight, and exercise regularly.

Studies reported in the journal Cancer Epidemiology, Biomarkers and Prevention (Volume 15, page 1588 ) associate exercise with a lowered risk of colorectal cancer. Researchers in this study thought exercise might help prevent cellular changes associated with development of polyps in the colon lining. They recruited 102 men and 100 women ages 40–75 and randomly assigned them to a control group or to a group that did 60 minutes per day of moderate to vigorous exercise six days a week for a year. All had a colonoscopy within three years of the study and after the study.

All men who exercised 250 minutes a week had a reduction in potentially cancerous cell growth, and men who exercised longer (300 minutes a week) had twice the reduction in cell proliferation of the control group. Those who increased cardiovascular fitness by at least 5% had more than double the reduction of those who exercised but did not have the same cardiovascular improvements.

However, women in the same study who also exercised or increased cardiovascular fitness did not have notable changes in the markers of cell proliferation.