Optimum Nutrition Serious Mass 12lb

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Save $15.74
$5.58 per serving
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Optimum Nutrition Serious Mass is the ultimate weight gain protein formula that supplies hard gainers and ectomorphs, with the calories needed to pack on pounds of quality muscle and develop a strong, solid and muscular physique. 

This mass gainer delivers nutritional support in the form of 1250 calories, 50 grams of quality blended protein and over 250 grams of carbohydrates in each serve. Add in Creatine Monohydrate and Glutamine into the mix and you have the perfect partner to your intense strength training workouts.

What's in Optimum Nutrition Serious Mass Protein?

  • 50 grams of protein from a combination of faster and slower digesting sources
  • 250-plus grams of carbohydrates to support fueling of intense workouts which aid in the replenishment of glycogen stores - with no added sugar
  • Enhanced with creatine, glutamine for muscle growth and recovery
  • 25 vitamins and essential minerals including B-vitamins and antioxidants

As it is difficult to consume enough calories through regular eating and food, Serious Mass brings quality calories in the form of a tasty shake which can be used in between meals and immediately after your workout. 

Between Meals: Drink 1/2-1 serving of Serious Mass between meals to maintain positive nitrogen balance and support a high-calorie diet. Post-Workout: Begin drinking 1/2-1 serving of Serious Mass 30-45 minutes following exercise to support maximum recovery. Before Bed: Drink 1/2-1 serving of Serious Mass about 45-60 minutes before bed to provide nutrients to recovering muscle throughout the night.


Note: For best results use Serious Mass combined with intense weight training (3-5 times per week) and a sensible whole foods diet. Also, keep in mind that sufficient recovery between workouts impacts your ability to gain lean mass. Allowing at least 48 hours between workouts involving the same body parts is recommended.


Supplement Facts
Serving Size: 2 Scoops (334g)
Servings Per Container: 16
Amount Per Serving
Calories 1250
- Calories From Fat 40
Total Fat 4.5g
- Saturated Fat 1.5g
Cholesterol 80mg
Total Carbohydrate 252g
- Dietary Fiber 4g
- Sugars 20g
Protein 50g

Vitamin A 5000IU
Vitamin C 60mg
Vitamin D 200IU
Vitamin E 30IU
Thiamin 4.8mg
Riboflavin 4mg
Niacin 50mg
Vitamin B6 5mg
Folic Acid 400mcg
Vitamin B12 10mcg
Biotin 300mcg
Pantothenic Acid 25mg
Calcium 590mg
Iron 8mg
Phosphorus 430mg
Iodine 150mcg
Magnesium 140mg
Zinc 15mg
Selenium 70mcg
Copper 1.6mg
Manganese 2mg
Chromium 120mcg
Molybdenum 75mcg
Sodium 410mg
Potassium 1560mg

Creatine Monohydrate 1g
L-Glutamine 500mg
Glutamine Peptides 500mg
Choline (as choline bitartrate) 250mg
Inositol 250mg
PABA (para-aminobenzoic acid) 5mg


IMPORTANT: Always check with a Health Professional before using any supplements. Especially if you are under 18 years of age, have any known or suspected medical conditions and/or are taking any prescriptions or medications. Always read the entire label prior to using. Never exceed the recommended dosage.


Optimum Nutrition Serious Mass review by maor1k1d
  • Flavour
  • Formula
  • Effectiveness

I used this in conjunction with a high calorie diet while I was trying to pack on some quality size. Being a hard gainer, even eating a tonne of food didn't do too much for me. So with O.N. Serious Mass I was blown away by the quality of the calories. Most weight gainers i've tried previously have an extremely sugary taste, or have an odd paste taste. O.N. was leaning more towards the paste side, but still I was able to enjoy the flavour. It might just be that I don't like to use too much liquid, i'd rather a smaller, thicker drink, than a smooth, but twice as much gainer. Along with the extra calories I was trying to consume with my high activity job at the time, it just made for easy calories when it wasn't viable to sit down for 30 min and eat a protein/carbs/fats meal. I'd definitely recommend this to anybody trying to put some size on without having to drink pure sugar for 20 minutes.

Optimum Nutrition Serious Mass review by Aprilia
  • Overall
  • Flavour
  • Formula
  • Effectiveness

I have tried the ON Serious Mass chocolate and vanilla flavours. The vanilla is by far the best. It mixes reasonable easily and the vanilla is a great flavour to blend with fresh fruit. The formula has a comprehensive list of supplements added - vitamins, amino acids and minerals. By far the most comprehensive of any mass gainer. I have tried this as well as Mutant Mass (still have half a bag of MM left - terrible taste). You will gain weight on this product. I use it as a meal replacement by blending with fresh fruit, yoghurt, yakult, non-fat milk and coconut water. Like the effect of a lot of these supplements, you might get diarrhea.

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