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Optimum Nutrition Serious Mass Protein

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Product Description

Optimum Nutrition Serious Mass is the ultimate weight gain protein formula that supplies hard gainers and ectomorphs, with the calories needed to pack on pounds of quality muscle and develop a strong, solid and muscular physique.  One of Sprint Fit's favourites: this mass gainer delivers nutritional support in the form of 1250 calories, 50 grams of quality blended protein and over 250 grams of carbohydrates in each serve. Add in Creatine Monohydrate and Glutamine into the mix and you have the perfect partner to your intense strength training workouts.

Optimum Nutrition Serious Mass Protein features:

  • 1250 calories and 50g of protein helps reach serious weight gain goals
  • 50 grams of protein from a combination of faster and slower digesting sources
  • Over 250g of carbohydrates to support fueling of intense workouts which aid in the replenishment of glycogen stores - with no added sugar
  • Enhanced with creatine and glutamine for muscle growth and recovery
  • 25 vitamins and essential minerals including B-vitamins and antioxidants.
  • Less than 5g of fat per serving
  • Delicious taste

As it can be difficult to consume enough calories through regular eating and food, Serious Mass brings quality calories in the form of a tasty shake which can be used in between meals and immediately after your workout. Serious Mass is consumed to help support a calorie surplus for weight gain and muscle building. The added 1g of Creatine Monohydrate has been shown to support muscle strength, power and size when combined with high intensity activities. 


Available Sizes:
Container Size: 2.7KG (6Lb)
Serving Size: 2 Scoop (336g)
Servings Per Container:8

Container Size: 5.44KG (12Lb)
Serving Size: 2 Scoop (336g)
Servings Per Container: 16


Please Note: Nutritional Information is to be used as a guide only, actual values may differ between flavours and sizes and when formulations are modified or updated by the manufacturer. 
Contact us if you have any questions regarding this products ingredients.


All orders $50 and over receive Free* Shipping Nationwide 

Estimated Delivery Times*:

Auckland and North Island – Overnight

However many Auckland orders will be delivered the same day depending on what time the order is placed)

South Island – Overnight (For larger parcels allow 2 business days)

Same Day/Evening Express Shipping upgrade available at checkout for select suburbs*

Click here to view the full Shipping Details and Returns Policy.


Optimum Nutrition Serious Mass Reviews

4.65/5 based on 119 reviews
5 star
4 star
3 star
2 star
1 star

Overall Rating

9.3 /10

119 Ratings

Average Flavour Rating

9.6 /10

6 Flavours

Top Rated Flavour

10 /10



10/10 Banana

Good product, lots of calories using it at a lower dose rate to make it last and to build up to full dose. Flavour is great consistency prety thick like a full on milkshake.

10/10 Vanilla

Good mass protein high calorie and good protein

10/10 Strawberry

10/10 Vanilla

Great for weight gain. In a couple months I’ve gone from 57kgs to 64kgs 2 scoops with milk ???? On my 4th purchase ??

10/10 Vanilla

I got this for my son for his birthday at his request. He loves it! Very happy.

7/10 Vanilla

Great value for money, not the best tasting but still works effectivley.

10/10 Vanilla

10/10 Strawberry

10/10 Chocolate

10/10 Banana

Tastes so good mixes very well with milk easy to drink and doesn’t fill you up heaps so great for bulking easy was to get some extra calories in and very good if you need calories in a rush

8/10 Chocolate

Great supplement. Highly recommended!!

10/10 Vanilla

This wasn't my first purchase of this product. Ibe of the best on the market in my opinion. Wide scale of nutrients, next to no sugar, goid taste, great digestivity and you actually gain weight.

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