Optimum Nutrition's Serious Mass is the ultimate weight gain formula designed to help individuals who find it difficult to gain weight develop the physique they desire. This supplement provides 1250 calories per serving to boost daily calorie intake, 50g of high-quality protein to support muscle growth and repair, and over 250g of carbohydrates to aid muscle recovery. It also contains 3g of added Creatine to support performance per serving. Serious Mass is an ideal formula for supporting weight gains and can be enjoyed post-workout and between meals. It is available in a range of sizes and flavors and comes as a ready-to-mix powder with protein, carbohydrates, vitamins, and minerals. Sweetener is included.