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Optimum Nutrition Serious Mass Protein Reviews

4.65/5 based on 121 reviews
5 star
(96)
4 star
(21)
3 star
(2)
2 star
(0)
1 star
(2)

Overall Rating

9.3 /10

121 Ratings

Average Flavour Rating

9.6 /10

6 Flavours

Top Rated Flavour

10 /10

Chocolate

Write Review
5/5
Really good mass gainer, trust this brand 100% and it always helps me achieve the results I’m looking for while I’m in a bulking phase. Makes it a lot easier to bulk as there is a lot of calories in here which make my life easier while at work during the day. As I can substitute it as a meal.
5/5
Sprint Fit is really good to shop products because they are 100% original. I got on serious mass gainer. It's really good. Thanks Sprint Fit.
3.5/5
The scoop is huge. Easy to drink and tastes delicious. Great value for money and I've noticed the difference. Been using for a month now.
4.5/5
Tastes good, arrived quickly, well worth the money
5/5
Speedy delivery, great service arrived exactly as ordered, mixes easy with Sprint Fit hand shakers, I went with choc flavor mixed half with milk in one shaker the other half with water in Another and could not tell the difference in taste both were awesome (maybe a bit to good). Now for results, back in a couple of months to confirm if it works or not!
5/5
Got this as a gift and they are very happy, Awesome product and outstanding customer service.
5/5
Taste great!! 1 week only and seems work well !
5/5
Great product, Easy to mix and great taste too. My orders normally arrive the following day - great service.
5/5
Smooth taste easy to mix I gained muscle mass while taking this supp highly recommended. Shipping was fast got products overnight
5/5
Hey there, If your reading this review you've come to the right place. I have been using this product nearly 3 weeks now and it works. Absolutely LOVE it, excellent product and LOVE all the free gifts too. Thanks SPRINT FIT.
4/5
Great gainer, great service with prompt delivery.
5/5
5 stars for these guys, I literally cannot believe how easy & efficient the whole process was!! Super fast delivery too!
5/5
The best mass gainer for me! Its really working out
5/5
Great service, great products and especially great prices. Will only use Sprint for all my products and love all the free gifts thanks Sprint keep up the good work!
3.5/5
Good all round gainer. Tastes so good!
4.5/5
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.
5/5
Yum yum yum
0/5
awesome mass gainer, i commonly use it as a meal replacement and always fill me up!
5/5
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.
5/5
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.
4/5
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
5/5
Great powder! Tastes very good and I got good results after a week.
5/5
Product does what it says.. gained 12 lbs over 12 week period. Shake is very very thick which I like!
2.5/5
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.
2.5/5
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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