For insulin sensitive overweight patients, 1 session of exercise improves metabo...( HILTON HEAD SCOne out of every three...)

HILTON HEAD, SCOne out of every three Americans is obese. These individuals are at greater risk for additional diseases, since obesity leads to other health problems, such as diabetes.

Obesity-related complications are associated with an abnormal fat metabolism in the muscle. As a result, accumulated fat by-products inside the muscle affect insulin resistance. To avoid the build up of fat by-products, fat must either be oxidized (burned, as in exercise) or stored (as benign fat) in muscle.

A team of researchers has examined the effect of exercise on fat accumulation in a new study involving five obese women. In one session the women overate and did not exercise; in a follow-on session they overate and did exercise. The researchers found that:

• the body's fat-burning oxidation rate was reduced after one day of overeating;

• conversely, just one session of exercise increased the rate of fat-burning oxidation; and

• exercise increased the amount of fat that would eventually be stored in the muscle.

The findings indicate that even one bout of exercise helps to reduce the fat by-products inside the muscle, which affects the insulin sensitivity. The findings also suggest that a single session of exercise "steers" muscle fat towards oxidation, thereby avoiding the accumulation of fat by-products.

The study was conducted by Andrea Cornford, Minghua Li, Simon Schenk, Matthew Harber and Jeffrey Horowitz, Division of Kinesiology, University of Michigan, Ann Arbor. Their research is entitled "Alteration in Lipid Metabolism After One Day of Overeating Are Reversed by a Single Session of Exercise." They will present their findings at a meeting sponsored by the American Physiological Society (APS; www.The-APS.org). The conference, The Integrative Biology of Exercise V, will be held September 24-27, 2008 in Hilton Head, SC. '/>"/>