









🚀 Serious Mass, Serious Gains — Don’t just grow, dominate your muscle game!
Optimum Nutrition Serious Mass is a high-calorie weight gainer designed for athletes and fitness enthusiasts aiming for rapid muscle growth and weight gain. Each 334g serving delivers 1,250 calories, 50g of whey protein, 251g carbohydrates, and 3g creatine, complemented by 25 essential vitamins and minerals. Ideal for post-workout or between meals, it supports muscle recovery, energy replenishment, and enhanced performance with a delicious strawberry flavor.














| ASIN | B0001FSWMM |
| ASIN | B0001FSWMM |
| Age Range Description | Adult |
| Allergen Information | Contains: Cereals containing Gluten, Egg may contain, Milk, Nut, Peanuts may contain, Soy |
| Best Sellers Rank | 1,070 in Health & Personal Care ( See Top 100 in Health & Personal Care ) 22 in Whey Nutrition Protein |
| Brand | Optimum Nutrition |
| Carbohydrate | 75.0000 g |
| Country of origin | United Kingdom |
| Country of origin | United Kingdom |
| Customer Reviews | 4.5 4.5 out of 5 stars (3,620) |
| Customer reviews | 4.5 4.5 out of 5 stars (3,620) |
| Date First Available | 12 Feb. 2009 |
| Energy (kJ) | 1573.00 kJ |
| Energy (kcal) | 375.95 kcal |
| Fat | 1.8000 g |
| Format | Powder |
| Is discontinued by manufacturer | No |
| Item model number | 1031917 |
| Manufacturer | OPTIG |
| Manufacturer contact | 4 Waterside, Dublin 24, Ireland |
| Product Dimensions | 29.21 x 13.97 x 40.64 cm; 5.44 kg |
| Protein | 15.0000 g |
| Salt | 0.5600 g |
| Serving Recommendation | 334 Grams |
| Serving Size | 100 g |
| Units | 5450.0 Grams |
| Weight | 5.82 kg |
T**S
Good
It's helping me put on weight. I added a tablespoon of peanut butter and a banana, tastes really good with the strawberry one. This seems to be the best mass gainer, I've looked around and this is always said to be the best with approved ingredients. It is sweet tasting but if you add some peanut butter it will tone down the sweetness. I'm just doing pushups, ab crutches, planks and dumbbells. I don't go to a gym. With noticeable growth to my arms and chest, just started working on abs to balance it out. I only started to see results after drinking this stuff. Good price on this bigger bag so I think I'll get this one again in the future.
L**G
It’s a must buy ! Best & high quality mass gainer! Imo the best out there
I only use this brand of mass gainer… reason being it sits will in my digestive system, it definitely does what it supposed to do. I have used other brands, cheaper brands but they do not pack the punch this do 💪 I have literally been buying this for over 10 years now & will never use other cheaper products. Yes it’s expensive but quality costs money simple! It mix fairly well. The ingredients are of high quality. In my opinion you will not be disappointed & like I said you will definitely be getting the performance you want. I packed on good quality weight… 2st in 3 months but that’s training 5 days a week keeping meals healthy. Hope you find this review helpful.
B**N
Excellent for Weight and Mass Gain
This protein powder is an excellent for anyone serious about gaining mass. The large size offers fantastic value, and the mix is effective and potent. It mixes well, taste good and is essential for hitting those high-calorie and high-protein goals. Highly recommended for fast, reliable results!
J**E
3 different batches
This is the 3rd time I've ordered this brand. All 3 times were strawberry flavour. The first batch was a standard fake strawberry taste, nothing special. The second one was delicious! Tastes like strawberry milkshake when mixed with water! I really enjoyed it so I bought more. Only this time I have to hold my nose to drink it because it smells that bad! And don't even get me started with the taste! Isn't even remotely close to strawberry let alone any known living fruit. Plus when this batch is blended, it is flourecent red, while the last two batches were strawberry pink. What is going on here guys??
G**L
Good taste, strawberry flavour
I'm struggling to gain weight very bad, I'm 1.80 meters tall and 30 yrs old and my metabolism is crazy, I put hard weight and is fair to say I dont eat too much as well, just 2 meals a day, sometimes only one but I've decided to change that and after reading alot of reviews of top mass gainers, I have decided to try this one. So I ordered myself the strawberry 5 kg bag along with a blender and I'm following the next plan: I am spliting the serving in 2: one in the morning and one in the evening before work. I put 350 ml whole milk, 1 full cup of proteins(~170 grams), 2 big spoons of peanut butter, I'm adding 5 more grams of creatine , 50 grams of oats and 1 banana for flavouring and must say the taste is amazing and the vascosity is not too high, is drinkable. Have managed to drink it whole after 20 mins after breakfast. This combination will give you around 1200 calories per shake, so 1200 calories in the morning and 1200 calories in the evening. Thats 2400 calories just from the shakers! For meals I will try to eat as many eggs in the morning with a salad and for dinner one piece of chicken breast with potatoes and salad. Inbetween meals I will eat 2 snickers, 2 kinder bueno bars and 1 croissant 7 days. By my maths, with the shake combination and meals and snacks, I will have around 4000 calories per day intake, my goal is to get 10 kg in 1 month and 10 days. Today is day 1 and I weigh 64 kg, will update you next week on my current weight!
H**A
….
Excellent
S**T
Good value and tasty
Very good tasting powder and very good value for money and stomach doesn’t feel heavy after drinking definitely recommend
A**R
Hard gainer? Look no further!
Worked a treat! I wouldn't recommend strawberry, i started out on chocolate and it was just about right for my taste buds, although a little thick i eventually grew to enjoy it (or tolerate depending how i felt). I struggled to put weight on in the past, BUT this was my own fault, i was only 8.5 stone and was 5"10 tall and never took the gym serious which always made me doubt growing in size. I will say this, i used the MyFitnessPal app on android to calorie count, i set a goal of 11 stone and tracked every bit of food i ate, i then used serious mass to help meet or exceed my daily calorie goals. I kept to this strict routine for a few months and saw myself growing exponentially! I also cut down on heavy cardio and lifted light with long reps at first and now i am lifting heavy with shorter reps and i can definitely see an improvement. The reason i write this is because i always considered myself a hard gainer, but after actually putting in the extra effort at the gym and with the calorie counter app (and not just taking the weight gainer hoping for the best) i am now 10.2st which is just muscle mass. Also as a side note: - You may grow a bit of a pot belly, since i have stopped using the gainer i have managed to lose the belly and keep the mass, i might be sensitive to lactose but i'll keep this here as a heads up. - I only used one scoop a day to meet my calorie goals (sometimes two) but i made it my best effort to NEVER miss a day of taking the mass gainer and stuck to my routine.
K**N
Very good protein
N**S
Not only is this an Amazon a quality amount of protein, but it tastes so good! Usually, protein shakes taste worst than anything else but the STRAWBERRY flavor is fantastic (all other flavors like chocolate and peanut butter are absolute dog poop) you cannot go wrong with strawberry. At first, if you’re first starting to work out, you might have some stomach issues, but you have to very slowly increase the amount and your body will get used to it. I ONLY use one scoop because two is ridiculously too much and I don’t want to end up with liver or kidney failure lol but one scoop is good. Once you get used to it, no stomach issues at all! Very effective, I have gotten so many compliments from others who have been at the gym for longer and ache for my results. You must remain consistent with the gym and workouts, do very intense workouts. If you don’t, then you’ll just get fat from this lol I advise to only use one scoop size to make the bag last longer and prevent any health issues, two scoops is ridiculously too much. Be consistent and you can play with some mix ability and throw banana or some other fruits if you want. I would recommend and will continue to buy this after so many years of already doing so
A**K
Bana patlak geldi ürü
M**L
Gutes Produkt.
B**L
It's good but bad 👎service
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