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Optimum Nutrition Serious Mass

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Free with the purchase of any 5.45kg Optimum Nutrition Serious Mass.
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Supports muscle building and weight gaining. More than 1260 kcal per serving to help boost your calorie intake. 50 g protein per serving to help build and maintain muscle. More than 250 g carbohydrates per serving to help support muscle Recovery.

OPTI Serious Mass

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2720 g (2.72 kg)
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5450 g (5.45 kg)
or 4 interest-free payments of $27.49
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or 4 interest-free payments of $15.74
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or 4 interest-free payments of $15.74
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or 4 interest-free payments of $15.74
Learn more
or 4 interest-free payments of $27.49
Learn more
or 4 interest-free payments of $27.49
Learn more
or 4 interest-free payments of $27.49
Learn more
or 4 interest-free payments of $27.49
Learn more


To gain weight, you need to consume more calories than you expend. For many aspiring to hit their calorie goals and put on size, a highly active metabolism, weak appetite or on-the-go lifestyle can make it a real challenge to get enough calories from food alone.
SERIOUS MASS is the ultimate muscle building and weight gain formula. With 1,250 calories per 2-scoop serving and 50 grams of protein to support muscle recovery, this powder makes the ideal post-workout and between meals shake for sizing up your goals. SERIOUS MASS provides you with the tools you need to support your weight gains goals.


  • Training longer and harder to gain more muscle
  • Finding it difficult to consume enough calories through food alone
  • Finding it challenging to gain weight regardless of your dietary intake
  • Serious Mass provides you with all the tools you’ll need to pack on the pounds


  • 1,250 Calories per Serving to Help Support a Calorie Surplus for Weight Gain and Muscle Building
  • 50 Grams of Blended Protein per Serving to Help Build and Maintain Muscle
  • 252-254 Grams of Carbohydrates (with no added sugar) to Help Fuel Workouts and Aid in Replenishment of Glycogen Stores
  • 1g Creatine Monohydrate To Support Muscle Strength, Power And Size When Combined With High-Intensity Activities
  • 20 Additional Vitamins and Minerals (including L- Glutamine)
  • Ideal Formula to Support Weight Gains
  • Available in a Range of Sizes and Great Tasting Flavours
  • Enjoy Post Work-out and Between Meals


Mix 2 scoops of the powder into 700-720ml of cold water or milk using an electric blender. This allows to you add in fruits, peanut butter and other calorie-contributing foods. TIP: New users should start with a 1-scoop half serving. Use post-workout and/or between meals to add calories, carbs and protein to your healthy, balanced diet.

Serving Size: About 2 Heaping Scoops (336 G) Average Quantity Per Serving
Protein50 g
Fat, total4.5 g
  - saturated2.5 g
Cholesterol110 mg
Carbohydrate252 g
  - sugars20 g
    - includes added sugars9 g
Dietary Fibre4 g
Vitamin A (as beta-carotene)750 mcg
Vitamin C (as ascorbic acid)60 mg
Vitamin D (as cholecalciferol)5 mcg
Vitamin E (as d-alpha tocopheryl succinate)20 mg
Thiamin (as thiamin mononitrate)4.8 mg
Riboflavin4 mg
Niacin (as niacinamide)50 mg
Vitamin B6 (as pyridoxine hydrochloride)5 mg
Folate (as folic acid)680 mcg DFE (400 mcg folic acid)
Vitamin B12 (as cyanocobalamin)10 mcg
Biotin (as d-biotin)300 mcg
Pantothenic Acid (as d-calcium panthothenate)25 mg
Choline (as choline bitartrate)250 mg
Calcium (as calcium citrate, dicalcium phosphate)600 mg
Iron (as ferrous fumarate)8 mg
Phosphorus (as dicalcium phosphate, dipotassium phosphate590 mg
Iodine (as potassium iodide)53 mcg
Magnesium (as magnesium aspartate)140 mg
Zinc (as zinc citrate)15 mg
Selenium (as selenomethionine)70 mcg
Copper (as copper gluconate)1 mg
Manganese (as magnesium amino acid chelate)2 mg
Chromium (as chromium polynicotinate)120 mcg
Molybdenum (as molybdenum amino acid chelate)75 mcg
Sodium570 mg
Potassium (as dipotassium phosphate)1430 mg
Creatine Monohydrate3 g
L-Glutamine500 mg
Inositol250 mg
PABA (para-aminobenzoic acid)5 mg