Energysource 41 is a 39state of the art39 sports fuel for use during exercise and to help muscles recover after exercise energysource 41 combines a special mix of 4 parts complex carbohydrate to 1 part whey protein research shows that this ratio drives more energy into working muscles providing athletes with a 24 29 increase in endurance over carbohydrate only drinks and a 57 increase in endurance over water