Physical activity essential to cutting risk of chronic disease in older women.

2003 FEB 13 - (NewsRx.com & NewsRx.net) -- Getting regular, moderate-intensity exercise may be critically important for postmenopausal women who want to reduce their risk of cancer, heart disease, and other chronic diseases, according to a study led by researchers at Fred Hutchinson Cancer Research Center in Seattle.

The reason: Exercise effectively reduces intra-abdominal fat, a hidden risk factor for many chronic illnesses.

Lead investigator Anne McTiernan, MD, PhD, a member of Fred Hutchinson's public health sciences division, and colleagues report the results of the largest randomized clinical trial to assess the effect of exercise on overall and intra-abdominal obesity in postmenopausal women in the January 15 issue of the Journal of the American Medical Association. Researchers from Fred Hutchinson, the University of Washington, Yale University, and the University of Colorado collaborated on the study.

"Even if a woman who exercises regularly doesn't see the benefits of dramatic weight loss on her scale, our results indicate that she can feel confident that she is improving her health, because regardless of the amount of weight lost, we now know that exercise reduces hidden intra-abdominal fat, the most dangerous type of fat," said McTiernan, director of Fred Hutchinson's Prevention Center and an international expert on the impact of physical activity on cancer prevention. "This study gives us direct evidence that exercise can affect biology related to cancer and other chronic diseases in older women."

Reducing intra-abdominal, or visceral, fat is important because in addition to increasing the risk of cardiovascular disease and diabetes, among other conditions, such fat can raise insulin levels, which promotes the growth of cancer cells.

People with high levels of intra-abdominal fat may not even know it, McTiernan said, because it is hidden, deposited around the internal organs within the abdomen. "Most women don't know about intra-abdominal fat, but they should, since it is the most clinically significant type of fat and it's where women tend to store fat after menopause."

This yearlong study involved more than 170 previously sedentary, overweight, postmenopausal Seattle-area women. None took hormone-replacement therapy. Half were randomly assigned to a moderate-intensity, aerobic-exercise group and half, who served as a comparison group, attended a weekly hour-long stretching class.