Serious weight gain requires serious calories. Optimum Nutrition Serious Mass is the ultimate weight gain formula. For muscle building and weight gain More than 1260 kcal per serving to help boost your calorie intake 50g protein per serving 25 vitamins & supplements Those who need the extra calories most often have the toughest time consuming enough of them. For many aspiring to be bigger, Serious Mass is the ultimate in weight gain formulas. With over 1,250 calories per serving to boost daily calorie intake, 50g high protein to support muscle growth and repair, over 250g carbohydrates, and now with 3g of added creatine per serving to support performance, you’ve got nothing to lose and lots to gain. It is time to stop thinking small and get serious – SERIOUS MASS. Use anytime, it is quick, convenient and easy to prepare. Serious Mass is ideal between meals, after weight training as part of your recovery routine and before bed. Just mix two scoops of Serious Mass (334g) with 710ml of water to create a tasty, calorie-packed shake.