Optimum Serious Mass 6lbs
Optimum Nutrition Serious Mass — High-Calorie Mass Gainer (6 lbs)
Optimum Nutrition Serious Mass is the classic hard gainer's mass gainer — engineered to deliver a massive 1,250 calories, 50g of protein, and 254g of carbohydrates per 2-scoop serving. For ectomorphs and underweight athletes who genuinely struggle to eat enough food to fuel muscle growth, Serious Mass provides a convenient, drinkable calorie surplus that would take several full meals to replicate with whole food alone. Enhanced with 5g of creatine monohydrate, 8g of glutamine, and 25 vitamins and minerals per serving — it is a true all-in-one mass solution.
| Spec | Per 2-Scoop Serving |
|---|---|
| Brand | Optimum Nutrition |
| Size | 6 lbs (~8 full servings) |
| Calories | 1,250 |
| Protein | 50g |
| Total Carbohydrates | 254g |
| Total Sugar | 20g (10g added) |
| Fat | 3.5g |
| Creatine Monohydrate | 5g |
| Glutamine | 8g (naturally occurring) |
| Vitamins & Minerals | 25 included |
| Available Flavours | Chocolate, Vanilla |
Key Benefits
- 1,250 Calories Per Serving — A genuine mass-building calorie surge in a single shake. Replacing one or two whole-food meals with Serious Mass is one of the most effective ways for hard gainers to consistently hit a caloric surplus.
- 50g Protein Per Serving — Sourced from a blend of whey protein concentrate and other protein sources for a sustained amino acid release alongside the massive carbohydrate load.
- 254g Carbohydrates for Glycogen Loading — The high carbohydrate content refills muscle glycogen aggressively post-workout and provides sustained caloric energy for muscle-building processes.
- 5g Creatine + 8g Glutamine — Pre-built into the formula for strength, power, and recovery support without needing separate supplementation.
- 25 Vitamins and Minerals — A comprehensive micronutrient matrix that addresses the nutritional deficiencies common in athletes eating high volumes of food to support mass gains.
Best For
- Hard gainers and ectomorphs who struggle to eat enough calories to build mass
- Post-workout recovery requiring maximum glycogen replenishment and protein delivery
- Athletes in a structured bulk phase targeting significant weight gain
- Those who want protein, creatine, and micronutrients consolidated into one shake
Not Ideal For
- Athletes trying to lose fat or maintain lean physique — 1,250 calories per serving will drive surplus weight gain
- Those with diabetes or blood sugar management concerns (high carbohydrate and sugar content)
- Those with dairy allergies (contains whey protein — a milk derivative)
Ingredients & Allergens
Protein blend: Whey Protein Concentrate, additional protein sources. Carbohydrate blend includes maltodextrin and other carbohydrate sources. Added creatine monohydrate 5g. Contains: MILK, SOY. 25 added vitamins and minerals. Confirm complete ingredient list for your specific flavour on the product label before use.
Who Is This For?
Optimum Nutrition mass gainer is built for hard gainers, ectomorphs, and athletes who struggle to consume enough calories from whole food alone to support a caloric surplus and muscle growth. It is ideal for bulking phases and post-workout recovery windows.
Who Is This NOT For?
Not recommended for individuals already meeting their caloric targets through whole food, those prone to easy fat gain, or anyone on a caloric deficit. High carbohydrate content makes this unsuitable for low-carb or ketogenic diets.
Why Buy From Bulldog Nutrition?
Bulldog Nutrition is an authorized Canadian and US retailer of Optimum Nutrition products. We source directly from the brand — never from grey market or unauthorized distributors — so every order is genuine and fresh.
- ✓ Authorized Optimum Nutrition retailer — authentic products only, never grey market or counterfeit
- ✓ Ships across Canada and the US — fast, reliable delivery to your door
- ✓ 10+ years in business — a track record you can rely on
- ✓ 4.7/5 stars from 2,400+ verified customer reviews
- ✓ Ongoing support available — reach us anytime via email or live chat
Shipping Information
Bulldog Nutrition ships across Canada and the United States. Most orders are processed within 1 to 2 business days.
Free shipping is available on eligible orders over $100. Please note that drink cases are excluded from free shipping due to size and weight.
During extreme hot or cold weather, heat-sensitive or cold-sensitive items may be affected in transit. For full details, please review our Shipping Policy.
Product & Site Disclaimer
Website information is provided for general informational purposes only. Product details, images, ingredients, and labels may change without notice, so customers should always review the actual product packaging received before use. For full details, please review our Product & Site Disclaimer.
Need Help?
For the fastest assistance, please use Live Chat on our website. You can also text SUPPORT to 1-833-497-3885 or use our Contact Us page for order, shipping, returns, and general support questions.