MONDAY, Feb. 11 (HealthDay News) -- Among white men, exercise may cut the risk of developing prostate cancer, and it may also lower the odds of aggressive disease in those who already have the cancer, a new study indicates.

However, those benefits were not seen in black men, Dr. Lionel Banez, of the Durham Veterans Affairs Medical Center in North Carolina, and colleagues reported in the Feb. 11 online edition of the journal Cancer.

For the study, the researchers asked 164 white men and 143 black men undergoing a prostate biopsy about their exercise habits. White men who were moderately or highly active were 53 percent less likely to be diagnosed with prostate cancer than those who were mildly active or inactive.

But the investigators found no association between exercise levels and prostate cancer risk in black men, they noted in a journal news release.

And of the men who were diagnosed with prostate cancer, those who exercised were 13 percent less likely to have an aggressive form of disease that was likely to grow quickly and spread. However, when the researchers looked at this finding based on race, it remained significant in whites but not in blacks.

Previous research has shown that black men are more likely than white men to develop prostate cancer and to die from the disease, the study authors noted.

These new findings that black men may not benefit from exercise the way white men do could help explain why blacks are at greater risk for prostate cancer and aggressive prostate cancer, Banez suggested.

Further research is needed to learn why exercise might help protect white men but not black men, he pointed out in the news release. And although the study found an association between prostate cancer and exercise in white men, it did not prove a cause-and-effect relationship.

More information

The American Cancer Society has more about prostate cancer.