Study results show that eight weeks of physical activity can restore brain insulin sensitivity in severely overweight adults. This is an important breakthrough for patients suffering from obesity or type 2 diabetes. Insulin resistance affects a person’s metabolism and eating behavior and is one of the main risk factors for both conditions. Insulin nasal spray, administered through the nose, increases cerebral blood flow in the striatum and right tegmentum. However, the treatment had no effect on other insulin-sensitive brain regions. This study showed that insulin nasal spray increased CBF in the right lobe and striatum, but not in other regions. A program of moderate to vigorous aerobic exercise can improve insulin sensitivity. In particular, the combination of aerobic exercise and resistance exercise is beneficial. This type of exercise involves engaging the heart and lower body muscles and raising the heart rate for long periods of time. Muscle is a metabolically high tissue and requires a large amount of energy to repair itself. Exercise-induced changes in brain insulin action may be associated with changes in peripheral metabolism and perceived hunger. The associations between these changes are reflected in the mediation analyses. To test the mechanism behind the observed relationships, the researchers looked at measures of peripheral metabolism, such as the amount of VAT in skeletal muscle fibers.
