Flavors: Banana
In stock


Optimum Nutrition Serious Mass 6lbs | Mass Gainer For Hard Gainers

Optimum Nutrition's Serious Mass is the Ultimate Mass Gainer and Muscle Building Supplement. This formula packs in 1250 calories per 2 scoop serving along with 50 grams of protein, 250 carbs, 3 grams of creatine, and 25 essential vitamins and minerals your body needs. This supplement helps to build and maintain muscle and will help hard gainers put on some muscle mass. 

What is Serious Mass?

Optimum Nutrition's Serious Mass is the ultimate in weight gainer formulas. Serious Mass packs 1250 calories per serving along with a whopping 50 grams of protein, and 250 carbs, along with 25 essential vitamins and minerals. If you find that no matter how much you try to eat you still can't put on weight and/or muscle mass, give Serious Mass a try!

Can I Stack Serious Mass With My Normal Protein Powder?

Optimum Nutrition does not recommend taking your standard protein powder on top of Serious Mass. Serious Mass will more than satisfy your nutrition and protein needs on its own. 

Optimum Nutrition Serious Mass Product Highlights

  • Contains 1250 Calories Per Serving
  • 50 Grams of Protein Per Serving
  • Helps Build & Maintain Muscle
  • 250 Carbs Per Serving
  • 3 Grams Creatine Per Serving
  • Contains 25 Essential Vitamins & Minerals

Will Taking a Mass Gainer Make Me Fat?

If you use a mass gainer like Serious Mass without working out regularly or hard enough you will likely wind up putting on fat as opposed to muscle. If you're going to take a mass gainer make sure you're going to be training hard, otherwise you may be better off just increasing the amount of lean protein in your diet. 

Can I Use Serious Mass as a Meal Replacement?

While some users who have a hard time fitting in meals will use Serious Mass as a meal replacement, that somewhat defeats the point of using a mass gainer. Mass gainers are typically used on top of your 3 meals per day. In addition to allowing you to add additional calories and protein to your diet, the best way to take in nutrients is through real whole foods. 

Should I Only Take Serious Mass on Training Days?

Optimum Nutrition Serious Mass can be taken on training and non-training days. 

Optimum Nutrition Serious Mass Flavors

  • Banana
  • Vanilla
  • Chocolate
  • Strawberry
  • Chocolate Peanut Butter


Mix 2 scoops with 24 ounces of cold water or milk. Mixes great with fruits and greens as well. New users should begin with a 1 scoop half serving. 

Optimum Nutrition Serious Mass 6lbs Supplement Facts

Other Ingredients: Maltodextrin, Protein Blend (Whey Protein Concentrate, Calcium Caseinate, Egg Whites, Sweet Whey), Natural And Artificial Flavor, Medium Chain Triglycerides, Lecithin, Malic Acid, Acesulfame Potassium, Sucralose, Yellow 5.

Optimum Nutrition Serious Mass Supplement Facts


Store in a cool dry place after opening.