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Optimum Nutrition Serious Mass


Now £25.99

Banana In Stock
Chocolate In Stock
Cookies & Cream In Stock
Strawberry In Stock
Vanilla In Stock
Optimum Nutrition Serious Mass


Now £44.99

Banana In Stock
Choc Peanut Butter In Stock
Chocolate In Stock
Chocolate Mint In Stock
Cookies & Cream More In Soon
Strawberry In Stock
Vanilla In Stock
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Optimum Nutrition Serious Mass

ON’s Serious Mass is the ultimate weight gain formula

ON’s Serious Mass is the ultimate weight gain formula. If you find it difficult to gain weight, Serious Mass can help you develop the physique you've always wanted! Without adequate calories and quality protein, you simply can’t get any bigger, without enough fuel and muscle-building nutrients like protein, you simply won’t grow! Enter Serious Mass...

What Does It Do?
Each delicious shake delivers an incredible 1,250 calories, but no added sugar. This includes 50g of blended protein to support building muscle and 250g of carbs to fuel your workouts. That’s serious calories, serious protein and serious carbs...that’s Serious Mass!
Container Size: 2727g
Serving Size: 2 scoops (334g)
Servings Per Container: 8

Container Size: 5455g
Serving Size: 2 scoops (334g)
Servings Per Container: 16

Amount Per Serving:

Total Calories: 1250
Protein: 50g
Total Carbohydrates: 252g
-Sugars: 20g
-Dietary Fiber: 4g
Fat: 4.5g
-Saturates: 1.5g
Cholesterol: 80mg
Vitamin A: 5000 I.U.
Vitamin C: 60mg
Vitamin D: 200 I.U.
Vitamin E: 30 I.U.
Thiamin: 4.8mg
Riboflavin: 4mg
Niacin: 50mg
Vitamin B6: 5mg
Folic Acid: 400mcg
Vitamin B12: 10mcg
Biotin: 300mcg
Pantothenic Acid: 25mg
Calcium: 590mg
Iron: 8mg
Phosphorus: 430mg
Iodine: 150mcg
Magnesium: 140mg
Zinc: 15mg
Selenium: 70mcg
Copper: 1.6mg
Manganese: 2mg
Chromium: 120mcg
Molybdenum: 75mcg
Sodium: 410mg
Potassium: 1560mg
Choline (as choline bitartrate): 250mg
Inositol: 250mg
PABA: 5mg
Creatine Monohydrate: 1g
L-Glutamine: 500mg
Glutamine Peptides: 500mg


Maltodextrin, Protein Blend (Whey Protein Concentrate, Calcium Caseinate, Egg Albumen, Sweet Dairy Way), Creatine Monohydrate, L-Glutamine, Glutamine Peptides, Choline (as Choline Bitartrate), Inositol, Paba (Para-Aminobenzoic Acid), Artificial Flavor, Vitamin & Mineral Blend (Di-Potassium Phosphate, Magnesium Aspartate, Di-Calcium Phosphate, Calcium Citrate, Ascorbic Acid, Niacinamide, Zinc Citrate, Beta Carotene, d-Calcium Pantothenate, d-alpha Tocopherol Succinate, Selenomethionine, Copper Gluconate, Ferrous Fumarate, Manganese Amino Acid Chelate, Thiamin Mononitrate, Pyridoxine Hydrochloride, Riboflavin, Chromium Picolinate, Folic Acid, Biotin, Molybdenum Amino Acid Chelate, Cholecalciferol, Potassium Iodide, Cyanocobalamin), Medium Chain Tri-glycerides, Acesulfame Potassium

Please Note: Nutritional facts and ingredients may vary slightly between flavours
Add 2 heaped scoops of Serious Mass™ to a blender filled with 710ml (24oz) of water. Blend for 45-60 seconds, then add a few ice cubes and, if desired, calorie-contributing ingredients.

Tips: Mixing 2 scoops of Serious Mass™ with 710ml (24oz) of skimmed or semi-skimmed milk will give you a thicker, creamier, higher-calorie shake. New users may find it beneficial to begin with ½ of a serving daily for the first week, and then gradually increase to 1 or more full servings several times a day.

Serious Mass™ can be used to feed serious calorie needs in a variety of different ways.

Between Meals: Drink ½ - 1 serving of Serious Mass™ between meals to support a high calorie diet.

Post-Workout: Begin drinking ½ - 1 serving of Serious Mass™ 30-45 minutes following exercise.

Before Bed: Drink ½ - 1 serving of Serious Mass™ about 45-60 minutes before bed to provide nutrients to muscles throughout the night.

For best results, use Serious Mass™ combined with intense weight training (3-5 times per week) and a sensible, whole foods diet.
Reviews (30)

"mixes easily in shaker,tastes great.(chocolate)put on 6lbs in 14 days.being a hard gainer that is good."

Posted by malcolm price  (15th February 2016)


"waste of money.My body didnt respond to it and it tasted like a low fat shake. lots of vitamins but no real gains."

Posted by Mannekuin  (5th July 2014)


"on paper a really good gainer, put on 3kg, however having the full 2 scoops makes me feel ill and the taste is pretty grim (vanilla)"

Posted by gary  (17th December 2012)


"Disgusting, smelt like a pet shop and made me feel sick! (Strawberry)"

Posted by Dean Gibson  (14th August 2012)


"yeah you will gain a littlebit of fat using this due the excesss calories so i reckon to instead use an all in one to bulk up rather than is only extremely hardgainers who dont cant eat a lot should use"

Posted by james  (19th May 2012)

Write a Review
Q get this bak in stock asap i want it

It's back in I believe!

Q hi, i am trying to gain lean muscle mass without compromisng my 6 pack abs too much....i understand you will gain some bodyfat in order to gain some muscle size however i would like to keep my bodyfat gain to a diet is very good and lean...and i already take protein this the best product out there to help me gain mass with minimum bodyfat or is there a better product out there ???...and does taking this product mean i dont have to take additional protein supplement ???

As you already understand that taking in extra calories will result in muscle growth and a little body-fat gains then yes this product will help you with your goal.

Q Hi, my names moeed, but u can call me moe. My main goal is to gain muscle mass. Im 17 years old n i have a fast metablism n if i take this product and train 4-5 times a week, then would i see chagnes within less than 6 months? And also, can u give me more advice on how to use this product?

This product should be used to bump up calorie count for your day, increased calorie count will lead to increased weight gain. If you supplement this into your bulking regime then you can expect to see some results within 6 months given that your training and your nutrition are spot on too. We'd recommend supplementing with this product two or three times a day between meals, use one serving for immediately after your workout to help with recovery.

Q hi.... i am using Weider mega mass from a moth and i want to change to serious mass is there any side effect if i change to serious mass suddenly or i have to wait for some days....or i can use serious mass directly after mega mass.. please replay me .... thanks ....

You can switch directly from one to the other without any problems.

Q I am using serious mass for 2 weeks till now and i am taking 1 scoop in the morning after my training session but i dont see any difference so far,can you advice me if extra 1/2 scoop before bed time will be beneficial or will there be any side effects. 2) Can i take the CLA capsule along with serious mass .

If you are looking for size and strength gains then we would recommend taking 2 scoops twice per day and monitor your weight gain. You should be looking to gain on average 1-2 lbs per week of healthy weight. If this does not do the trick we would recommend taking a look at your diet and seeing where you can add in some extra calories. You should be looking to increase your daily intake of calories by around 500-1000 per day. Cla can also be consumed with serious mass or at any other time in the day.

Q i see this product contains multi-vitamin...and i currently take ANIMAL PAK multi-vitamin....if i start taking this product is it okay to discontinue additional multi-vitamin consumption or is the vitamin and minerals in a single serving of this not enough ?

It is safe to combine both products together.

Q Is this product suitable for vegetarians? (Halal)? As I'm currently taking mutant mass and found out today it isn't

If a product does not state on its nutritional label 'suitable for vegetarians' or carries the 'Halal' certification, then more often than not, it is not suitable for vegetarians or deemed a Halal product. If you require further clarification, I would advise contacting Optimum Nutrition directly using the following email address:; I hope this information is helpful.

Q when the 5.4kg comes back?

I realize this was a late response but it is in stock in all flavours now.

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