Weight Gain Powders are made up of large amounts if calories - carbohydrates and protein. Carbs are needed to store muscle glycogen and to release insulin which causes protein to be deposited into recovering muscles. Protein is the building block for muscles. Muscles are made of protein. In order for muscle to grow, you need extra calories, carbs, and protein (combined with hard workouts). Weight Gain Powders are very helpful to hard gainers who have a fast metabolism
and require higher caloric intake in their daily diet. Beware, weight gain powders can also stimulate fat storage. Look for weight gain powders that are low in sugar and high in complex carbohydrates like Up Your Mass, Monster Mass and True-Mass.