The main hormone responsible for directing energy into muscles is insulin produced by the pancreatic cells. When the muscle cells are refilled, insulin directs the excess energy into fat stores. Insulin blood level can be manipulated by diet, activity and sometime it is the result of medical conditions, such as diabetes. Therefore insulin sensitivity is the key to losing fat while building muscle mass.
Insulin is released into the blood, when there is too much sugar. Low carbohydrate intake keeps the sugar low and insulin is not triggered, therefore it won’t store the excess energy in fat tissue. Insulin sensitivity can also by improved by exercise. According to a study published in the Journal of Sport Medicine, a single bout of exercise can increase insulin sensitivity for up to 16 hours post workout.