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High Protein Shakes x3 When You Spend £69.99 - Use Code PS3

Serious Mass

  • Help boost calories intake with 1,250 kcals per shake*
  • 50 grams of Whey Protein – Helps build and maintain muscle
  • 251 g▲ CARBS – Helps support muscle recoveryᵒ
  • 25 Vitamins and Minerals

Product Overview

High Protein High Protein
Low sugar Low sugar
Low fat Low fat


Serious weight gain requires serious calories. However, those who need the extra calories most often have the toughest time consuming enough of them. For many aspiring to be bigger, a highly active metabolism, weaker appetite and on-the-run lifestyle can make it a real challenge to consume enough calories through whole foods alone. Serious Mass is the ultimate in weight gain formulas. With 1,250 calories per serving to boost daily calorie intake, 50g high protein to support muscle growth and repair, over 250g carbohydrates helping support muscle recovery , and now with 3g added Creatine to support performance per serving, you’ve got nothing to lose and lots to gain. It is time to stop thinking small and get serious – SERIOUS MASS®


Ready to mix powder with protein, carbohydrates, vitamins and minerals, with sweetener


  • 1250 Calories

  • 50 g of Whey Protein
  • 25 Vitamins and Minerals
  • Ideal formula to support weight gains
  • Enjoy post work-out and between meals
  • Available in a range of sizes and great tasting flavours

Suggested Use

Mix 2 heaped scoops with 710 ml of water. You can also add a serving to smoothies, protein balls, muffins, porridge or other meals as another great way to get a protein hit in the kitchen.

Nutritional Information

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

Customer Reviews

Overall Rating (4.7)
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Good Product

Review by Anonymous on Nov 8, 2023
Verified purchase
Little high in sugar but gets the job done if consistent.

Great Product

Review by Diz on Oct 29, 2023
Verified purchase
i love the way it taste, also its been helping with my recovery after workouts and hitting my weight goals!!


Review by David Beycker Díaz on Oct 10, 2023
Es un gran producto llevo usándolo ya un mes y veo un gran cambio a nivel energía ya que cuando entrenaba me daba sueño ahora es todo lo contrario quiero seguir entrenando tengo 31 años soy de Perú

It works

Review by Hitesh Patel on Oct 4, 2023
Verified purchase
I have been using this product for over a year now and it’s really effective when it comes to my weight gain goals and gym strength/muscle mass.


Review by Anonymous on Oct 1, 2023
Verified purchase
Using it for 3mths now. Consistence in taste and results

Amazing if your trying to get extra calories!!

Review by Wyatt on Sep 25, 2023
Verified purchase
Especially for a faster metabolism this really helps on getting the extra calories you need

Best protein powder

Review by Anonymous on Sep 22, 2023
Verified purchase
ON has the best products and their mass gainer has helped me tremendously

First Experience

Review by James on Sep 19, 2023
Verified purchase
I have been super skinny my entire life. I've never been able to gain any weight. I'm what they call a hard gainer. I'm now 64. As we age, men start to lose muscle mass, which can lead to a number of health issues affecting bone density and osteoporosis, which can be offset through weight training. At the recommendation of a friend, he suggested I should try Serious Mass in order to bulk up and add some muscle weight. I first tried mixing it with water, but I didn't like the taste. However, on the second round, I mixed it with lowfat milk, which was a real game changer. It really tastes like a milkshake. I started out with a half serving, as they advise, working up to a full two scoop shake. So far, I've put on six pounds, and I couldn't be happier. I'm working with a personal trainer who is helping me build strength for the long run. It's never too late to build a body that you love.

Greatest product

Review by Nik on Aug 18, 2023
Verified purchase
Love it and use it daily to maintain weight in my extremely active lifestyle

Improved !

Review by M.G on Aug 10, 2023
Verified purchase
I can tell , they have made the MASS PROTEIN much easier to dilute on a shaker bottle. Previously you would get a lump here and there while shaking. Really happy and satisfied with the protein . It’s lighter but heavier on the training. Hands down , best protein powder on the MARKET !

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