Glycogen is essential for high intensity exercise performance. A review concluded that elevated glycogen concentration can improve performance by 2-3% and endurance capacity by 15-25%. Muscle glycogen concentrations can be increased by eating a diet that is rich in carbohydrate. However, studies in the 70s suggested that extreme glycogen loading protocols resulted in very high muscle glycogen concentrations. These protocols employed combinations of high carbohydrate days, low carbohydrate days a
