Get the caloric boost you need to gain nutrient-rich weight with the Optimum Nutrition Serious Mass Supplement. Made with whey, casein and egg, the supplement mixes in a blender with the liquid of your choice and provides 1,250 calories, 50 grams of protein, 250-plus grams of carbohydrates and 25 vitamins and minerals per serving. Optimum Nutrition Serious Mass Supplement - Health Supplements at Academy Sports