If you need a reason to get started on an exercise program, especially if fighting a sedentary lifestyle and a bulging waistline, here's a good one: You may be accumulating deep abdominal fat that elevates your risk of diabetes and heart disease.

A study compared four groups of sedentary, overweight adults divided among those who did varying amounts of exercise (riding a stationary bike and walking on a treadmill) to those who didn't.

No big surprise here, the no exercise/sedentary group gained a substantial amount of visceral fat (8.6 percent) in six months. Conversely, those participating in the high dose/vigorous intensity group (equaling about 20 miles of jogging a week) lost about 7 percent of both subcutaneous and visceral fat. And the low dose exercise groups held their own as far as fat, meaning they just didn't lose any.

Visceral fat is particularly troublesome because it's the kind that accumulates around organs inside the belly (and is deeper inside the body than subcutaneous fat, which lies just under the skin). Increased levels have been associated with insulin resistance, cardiovascular disease and other metabolic syndromes.

What I liked about the study: They referred to exercise in terms of dosage, a concept very few patients or clinicians really appreciate or understand.

In fact, I believe exercise is one of the most powerful drugs that we have to treat type 2 diabetes. Unlike typical commercial drugs, exercise can actually cause one to go into permanent remission for diabetes.

Duke Medical News September 14, 2005

Journal of Applied Physiology, Vol. 99, No. 4, October 2005:1613-1618

MSNBC October 12, 2005