Optimum Nutrition

PROMO - Optimum Nutrition Serious Mass (2.73kg) + FREE Gold Standard BCAA (266g)

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Points earned on this product... 289 = £0.29
RRP £61.98
SAVE 53%
Availability: In Stock


Optimum Nutrition Serious Mass is the market leading weight gainer - it tastes delicious, packs a BIG calorie punch and contains premium quality ingredients as you'd expect from Optimum Nutrition.

WHILE STOCKS LAST we're throwing in a FREE FULL SIZE tub of Optimum Gold Standard BCAA with EVERY tub of Serious Mass!

Serious Mass is CHOCOLATE flavour and gold standard BCAA is COLA flavour.


Optimum Nutrition Serious Mass is the market leading weight gainer - it tastes delicious, packs a BIG calorie punch and contains premium quality ingredients as you'd expect from Optimum Nutrition.

WHILE STOCKS LAST we're throwing in a FREE FULL SIZE tub of Optimum Gold Standard BCAA with EVERY tub of Serious Mass!

Serious Mass is CHOCOLATE flavour and gold standard BCAA is COLA flavour.

Optimum Nutrition Supplements

Optimum Nutrition Serious Mass

Optimum Nutrition's Serious Mass is the ultimate weight gain formula for making serious gains. Featuring a blend of whey protein concentrate, isolate, casein and egg proteins plus fast absorbing carbohydrates, essential minerals and more to help you pack in the calories and pack on some size. If you're serious about building muscle this bulking season, this is the blend for you.

For serious muscle growth and maintenance, you need to be training hard and eating right. Consuming a higher protein intake and creating a calorie surplus is key to building muscle mass and protecting it through intense workout regimes. Optimum Nutrition Serious Mass contains over 50 grams of high quality protein per serving plus 250 grams carbohydrates to refuel your muscles and keep the gains coming. The Serious Mass formula comes complete with added creatine, glutamine and glutamic acid for enhanced performance and more rapid recovery.

Key Benefits

  • More Muscle Gains – With over 50 grams of protein and 250 grams of carbohydrate, Optimum Nutrition Serious Mass is the formula you need to make build serious muscle mass.
  • No Added Sugar – Serious Mass contains fast absorbing maltodextrin and no added sugars to replenish muscle glycogen and refuel after every workout.
  • Essential Vitamins and Minerals – This mass building blend is more than just protein and carbs, every serving is stacked with 25 vitamins and minerals to support your health and fitness-focused lifestyle.
  • Classic Flavours – Optimum Nutrition Serious Mass is available in your favourite chocolate, strawberry, banana and vanilla flavours to make a sweet and satisfying shake. Mix with water or milk and add any extra ingredients you like!

Who is Optimum Nutrition Serious Mass For?

Optimum Nutrition Serious Mass is a calorie dense blend designed for athletes who really find it difficult to gain weight and build muscle mass. This formula is the ideal choice to supplement your muscle building plan where increasing your protein and overall calorie intake is necessary to make the most progress possible. Optimum Nutrition Serious Mass contains dairy, wheat and egg.

When to Use Optimum Nutrition Serious Mass?

Mix two heaping scoops (1 serving of 344g) of Optimum Nutrition Serious Mass with 710ml water or milk to make a thick shake. For best results, we recommend drinking 1 serving 30-45 minutes after your workout and another serving 45-60 minutes before bed. Consume up to 2 servings a day depending on your calorie needs as part of a balanced diet.

Who Are Optimum Nutrition?

Optimum Nutrition are the World's No.1 sports supplement brand - with their flagship Gold Standard Whey having been the most popular whey protein supplement for ... well forever, they also have a huge range of safe, natural & effective sports supplements based on proven science.


We will take every effort to get you goods to you as efficiently and effectively as possible. All orders placed before 3pm will be shipped on the day of ordering subject to payment authorization and item availability.

Any items which are out of stock will be shipped as soon as they become available. If this causes a delay in your delivery, you will be notified and your order dispatched as soon as possible. If any items are unavailable, you will be contacted and offered a replacement or refund.

UK Delivery

If your order total is under £50 then you can choose one of:

  • Royal Mail Tracked - £2.95
    (1-3 Working Days)
  • DPD Next Day - £4.95
    (Guaranteed Next Working Day + 1 Hour Delivery Window)

If your order total is over £50 then you can choose

  • Royal Mail Tracked - FREE
  • DPD Next Day -1/2 Price - Only £2.49

Please be aware that the prices above are for areas classed as "UK Mainland" by DPD which does NOT include offshore islands, Scottish highlands or Northern Ireland.

Non-UK Delivery

Our website has a comprehensive postage system which takes into account the weight of your delivery and the destination address - to get a quote for your order please add the products you'd like to buy to your basket, go to the basket page and fill in the "Estimate Shipping & Tax" section to get the price.

BFPO Addresses

This shipping method is available for British Forces Posted Overseas and addresses only. Shipping is as with all other UK mailing but please check to see that the size and weight of your order does not exceed maximums for your BFPO destination number by checking with the BFPO website.

Please note that once we have shipped the item and handed over to the BFPO service we have fulfilled our contract and delivery responsibility. All queries and problems with delivery must be taken up by yourself with BFPO and any claims must be handled between yourself and them.

VAT Exempt

If this applies to you, the price you will pay for the goods will automatically be adjusted to remove the VAT element - you MUST choose the correct country on checkout for this to apply. We CANNOT refund the VAT once the order is completed.

You can also avoid paying VAT if you are having your goods sent to you in the UK, but are taking the goods abroad permanently within 3 months of making the purchase. You will have to pay the VAT with your order but by following the steps outlined you can reclaim the VAT from us:

Request a VAT Reclaim form from us; give us a call or email immediately after ordering. We will complete the relevant parts of this form before sending it to you with your goods. You will then take the form with you and the goods when you leave the UK and you should ask customs to fill in their section of the form at the airport, ferry terminal or channel tunnel when you leave the country.

When you reach your destination outside the EU, you can then send the completed form back to us and we will refund the VAT amount charged to the credit or debit card details you have filled in on the reclaim form


We stock the vast majority of products listed on our website in our Whitley Bay superstore and warehouse and these products are available for same day dispatch & next day delivery.

Due to the huge quantity of products we stock, we offer the ability to backorder products which have gone out of stock and less popular products which we don't carry stock of.

Depending on the brand these backorder products can take anywhere between 1 and 10 days to arrive into stock. We estimate 3-5 working days on average but please be aware that products from some brands can take a little longer

As always if you aren't sure or want a more accurate estimate just give our team a call or email!


You can return any product that is in an UNOPENED, RE-SALEABLE condition within 30 days as long as it is not marked as clearance. Please contact us before doing this so we can confirm this ahead of time - we recommend using a recorded delivery service for any returns as you will be responsible for ensuring it reaches us.

Please get in touch to confirm a return by email or phone before sending anything back. When sending a return it is important that you include:

  • Your order number
  • Your name & a contact telephone number
  • The reason for return

We will try and get your return processed as quickly as possible but if you don't send this information it can delay the return.


If you have ordered something and it doesn't fit then we can exchange for a more suitable size, stock permitting, but you will have to pay the return postage.


Our customers have the right to cancel their orders within 14 days unless their order has been dispatched. After the order has been dispatched, it is the customers responsibility to return the item in a saleable condition and receieve either a full or partial refund.

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