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  • For Muscle Building & Weight Gain Goals
  • 1,250 Calories per Serving to Help Boost Calorie Intake ¹
  • 50 Grams of Protein per Serving to Help Build and Maintain Muscle ¹ ³
  • 252-254 Grams of Carbohydrates per Serving to Help Fuel Workouts ¹

Product Overview

For Muscle Building & Weight Gain Goals

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.¹


  • High-Calorie Formula Supports Muscle Building³ and Weight Gain Goals¹
  • 1,250 Calories per Serving to Help Boost Calorie Intake¹
  • 50 Grams of Protein per Serving to Help Build and Maintain Muscle¹ ³
  • 252-254 Grams of Carbohydrates per Serving to Help Fuel Workouts¹
  • 3 Grams of Creatine Monohydrate per Serving
  • 25 Vitamins & Essential Minerals

Suggested Use

Mix 2 scoops of the powder into 24 fluid ounces 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.

Nutritional Information

Nutritional information will be shown when a flavour and/or size is selected.

Customer Reviews

Overall Rating (4.6)
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Excellent product

Review by Anonymous on Dec 4, 2022
Great flavor, easy to mix. I wouldn’t change it for a different one.

Best protein powder for bulking and getting stronger.

Review by [email protected] on Nov 29, 2022
As it says in the back, with serious mass there's nothing to lose and a lot to gain, the product lives up to its name, it has helped me and my friend put on some weight used with workouts, we both have fast metabolisms and it helps us get the calories we need for growth, it tastes delicious, I usually use it before going to sleep after the gym I would recommend it 💯, thank you serious mass.

Great product

Review by Marcelo on Nov 17, 2022
Excellent product


Review by Arturo on Nov 13, 2022
the flavor is great

Using this for 6 months

Review by Ashley on Nov 3, 2022
Amazing, really helped me achieve the weight goals i have

Been Using for a year and a half

Review by Baiza Mand on Nov 1, 2022
This has really helped me to boost performance and achieve my weight goals! Great Product!

Great Stuff

Review by Baiza Mand on Nov 1, 2022
I've been using serious mass for a long time and it has really helped me achieve my weight goals!!

My opinion

Review by Andrew Mora on Oct 29, 2022
I’m really satisfied with this product and its benefits!

Best gainer

Review by Jonathan on Oct 28, 2022
I’ve found this to be one of the best gainers on the market. The vitamin profile, creatine, and taste sets it apart. Optimum is a quality brand and product is a good value/price.

Been using for years

Review by Steve on Oct 25, 2022
Great product that mixes and tastes good, used for years