RRP £49.99
Save £7.04

Reflex Nutrition newest weight gainer designed specifically for hard gainers and all athletes wanting a very high quality source of protein and complex carbohydrates.

Full description


Instant Mass® Heavyweight provides the body with protein from Whey Protein Concentrate, Micellar Casein, Native Whey, Hydrolysed Whey Protein

The whey protein concentrate in Instant Mass® Heavyweight is made by separating the whey protein from the other components in milk. Hydrolysed whey protein is treated with enzymes to make it even faster to digest.
This product will feed the body energy, while the carbohydrates provide a long-lasting comprehensive energy source to enable the body to work out for longer, more intense periods.


5.4kg size:Mix 300g (approximately two level 250ml measures (there is a scoop included in the bag) with 700ml water in a shaker or blender.
When just starting with this product, you may find it beneficial to begin with half the quantity before slowly increasing to the full serving in order to make it fit into your personal calorie plan.

Consume Instant Mass® Heavyweight between meals to maintain a positive nitrogen balance, or drink 20-30 minutes after a workout for optimal results. Alternatively, take Instant Mass® Heavyweight 45-60 minutes before bed to contribute to muscle maintenance overnight.

Once mixed, consume the shake immediately and don't leave to stand.
For a shake that is more calorie-heavy and creamier, try the product with semi-skimmed milk.
Protein contributes to the growth and maintenance of muscle mass.
Creatine increases physical performance in successive bursts of short-term, high intensity exercise. The beneficial effect is obtained with a daily intake of 3 g of creatine.

This product is a food supplement and should be used in conjunction with food as part of a varied and balanced diet and healthy lifestyle, not as a substitute for such. Recommended consumption is one 300 g serving per day. Do not exceed the stated recommended daily dose. This product is not intended for use by persons under the age of 18. Keep out of reach of young children.


Product Form
Primary Ingredients
Choose your Goal
Muscle Gain & Size, Lean Muscle & Definition,
Time of consumption
After Workout
Dietary Needs
Vegetarian , Halal Certified,
Drug Tested for Sport
Special Offer

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We want you to be happy with every purchase you make. Accordingly, you may inspect the items you buy as if you were in one of our stores. However, whilst you are deciding whether to keep your purchases, you do have a statutory duty to take reasonable care of our goods. Therefore, please do not damage the items whilst you inspect them.

Where you have failed to take reasonable care of the goods, whether whilst in your possession or when returning them, we reserve the right to refund you in full less any amounts due by way of compensation to either repair the goods or to cover any loss.

If you wish to return a product you have purchased from our website, making note of any Non-returnable products, you may do so.

View or full Returns Policy here.

Customer reviews

3.3 / 5
3 reviews for Reflex Nutrition Instant Mass Heavyweight 5.4kg
eKomi customer reviews
Israel Mugisha
The product doesn't taste good and smells off incomparsion to products we bought in our local supplement store.
Rated 1 out of 5
I feel this product is of great benefit for any one who has been unable to train because of illness, accident or personel problems or anyone who wants to bulk up to help handling poundages necessary for strength, growth, overall development.
This is how it has personally helped me, hope it helps you too!
Rated 5 out of 5
Phillip Bell
Effective and works well. Might get bored of just one flavour. Goes quick so stock up.
Rated 4 out of 5