Optimum Nutrition Serious Mass Protein

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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. 

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.

What's in Optimum Nutrition Serious Mass Protein?

  • 50 grams of protein from a combination of faster and slower digesting sources
  • 250-plus grams of carbohydrates to support fueling of intense workouts which aid in the replenishment of glycogen stores - with no added sugar
  • Enhanced with creatine, glutamine for muscle growth and recovery
  • 25 vitamins and essential minerals including B-vitamins and antioxidants

As it is 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. 

Available Sizes:
Container Size: 2.7KG (6Lb)
Serving Size: 2 Scoop (334g)
Servings Per Container:8

Container Size: 5.44KG (12Lb)
Serving Size: 2 Scoop (334g)
Servings Per Container: 16

Add two heaping scoops to a blender or shaker with 700ml of water or beverage of your choice.  For maximum weight gain, take three servings daily; one in the morning, another in the afternoon, and a final serving at bedtime (20-30 minutes before going to sleep).


Free Shipping Nationwide:

Delivery Times
North Island - Overnight
South Island - +1 Business day
(Overnight delivery service available during check out) Rural - +1 Business day from the above times
Orders need to be placed before 3.30pm to make it on the final courier of the day

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

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Optimum Nutrition Serious Mass Reviews

4.9/5 based on 10 customer reviews
    Great product. I struggle to gain mass and have tried various mass gainers which have all been sub-par when compared to Optimum Nutrition's Serious Mass. Top quality for the price, and great tasting.
    Yum yum yum
    awesome mass gainer, i commonly use it as a meal replacement and always fill me up!
    one of the best mass gainers in the world. very low in sugar and high in protein. its expensive but its worth it. gained a lot muscle mass in a short period of time. banana is the best flavor.
    Since ON make one of the best whey protein powders, I thought I give their mass gainers a try during my off season and purchased aChocolate Peanut Butter. Cant fault anything on this. It mixes very well and works excellent with my protein pancakes. Plus it really tastes like Chocolate Peanut Butter. I have seen excellent results as well. Would recommend.
    Great product for those who dont get enough calories during the day. It has less sugar then other Mass gainers which is always great and gets the job done
    Great powder! Tastes very good and I got good results after a week.
    Product does what it says.. gained 12 lbs over 12 week period. Shake is very very thick which I like!
    Really happy with this product. Packing on gains in the right places but you do need to train hard with this product! I've only tried the chocolate flavour.
    I have been using Optimum Nutrition Serious Mass for a long time now, after trying quite a few mass gainers before it. The total number of calories is what does it for me, can’t find it anywhere else and the chocolate flavour is pretty damn good. I struggle to eat enough calories in a day for really good muscle growth but i find the job a lot easier with serious mass.

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