ON Serious Mass 12LB
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ON Serious Mass 12LB - Chocolate is backordered and will ship as soon as it is back in stock.
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Product Description
Product Description
Optimum Nutrition Serious Mass – 12LB Mass Gainer Formula
Built for hard gainers and serious athletes, ON Serious Mass delivers a powerful calorie-dense formula to fuel muscle growth, support recovery, and help you hit your size goals faster. Each serving packs 50g of protein, 254g of carbohydrates, and 1,250 calories — everything your body needs to grow.
Why Serious Mass?
- 50g Protein per serving — supports muscle building and repair
- 1,250 Calories — ideal for high-calorie bulking phases
- 254g Carbohydrates — replenishes glycogen stores and fuels training
- 12LB / 5.44kg bag — 16 servings of serious fuel
- Trusted by athletes in 100+ countries for 35+ years
Who Is This For?
- Hard gainers looking for easy calories to add to their bulking routine
- Athletes in high-volume training or bulking phases
- Anyone needing a convenient, high-calorie protein supplement
Nutrition Highlights (per 2-scoop serving)
- Calories: 1,250
- Protein: 50g
- Carbohydrates: 254g
- Fat: 4g
- Sodium: 510mg
Manufactured in the USA by Glanbia Performance Nutrition. Always refer to the product label for complete nutrition facts, allergen information, and usage guidelines.
Shop the full Optimum Nutrition lineup or browse all Mass Gaining Proteins. Want to learn more? Read our Complete Buying Guide to Protein Powders in Canada.
Directions and Suggested Use
Directions and Suggested Use
Ingredients
Ingredients
Questions & Answers
Questions & Answers
How many calories are in ON Serious Mass per scoop?
A 2-scoop (334 g) serving of ON Serious Mass provides 1,250 calories, along with 50 g of protein, 254 g of carbohydrates and 4 g of fat.
What are the ingredients in ON Serious Mass?
ON Serious Mass is made with maltodextrin, whey protein concentrate, natural and artificial flavour, lecithin, acesulfame potassium and sucralose. It contains milk and soy.
How much protein is in ON Serious Mass?
Each 2-scoop serving of ON Serious Mass delivers 50 g of protein from whey protein concentrate, along with 254 g of carbohydrates from maltodextrin.
How many servings are in the 12LB bag of ON Serious Mass?
The 12 lb (5.44 kg) bag of ON Serious Mass contains 16 servings, each mixed as 2 scoops with 250–500 mL of cold water or milk.
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ON Serious Mass 12LB
ON Serious Mass 12LB
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Why these go together
Gainers supply the calories — creatine converts the surplus into strength, and a big shaker makes the servings manageable.
