Insulin Resistance Countered By Exercise

Using imaging technology, U.S. researchers found insulin resistance in skeletal muscle leads to alterations in energy storage linked to metabolic syndrome.

The alterations in energy storage — molecular events — lead to metabolic syndrome, a cluster of conditions that includes the most dangerous heart attack risk factors: pre-diabetes, diabetes, high blood pressure and changes in cholesterol previously linked primarily to abdominal fat.

The study, published in the Proceedings of the National Academy of Sciences, demonstrates that insulin resistance in skeletal muscle — caused by decreased ability of muscle to make glycogen, the stored form of carbohydrate from food energy — can promote an elevated pattern of lipids or fats in the bloodstream that underpins the metabolic syndrome.

Gerald I. Shulman and Kitt Falk Petersen of the Yale University School of Medicine looked at how nutrients are channeled in the body in both insulin resistant and insulin sensitive human subjects who had none of the other confounding factors typically associated with obesity and type 2 diabetes.

What we found is that (insulin) sensitive individuals took the energy from carbohydrate in the meals and stored it away as glycogen in both liver and muscle, Shulman said in a statement.

The good news, according to Shulman, is that insulin resistance in skeletal muscle can be countered through a simple intervention — exercise.