Bulk up Bundle – Reflex Nutrition
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15% off bundle offer

Bulk up Bundle

£83.47 £70.95

Built for those looking to gain size, recover well and keep making progress.

  • High calorie

    Made to bulk

  • Promotes muscle growth

    Bulk the way you want

  • Manufactured in the UK

    A product you can trust

Big on protein, carbs, and calories—the ultimate choice for muscle and weight gain. Powered by our punchy pre-workout and Zinc Matrix for peak performance.

🚚 FREE SHIPPING OVER £50. SEE BELOW FOR DELIVERY CHARGES.

⏱ NEXT DAY UK DELIVERY ORDER BY 13:00

Or express checkout with

PRODUCT INFORMATION

Big on protein, carbs, and calories—the ultimate choice for muscle and weight gain. Powered by our punchy pre-workout and Zinc Matrix for peak performance.

DELIVERY & RETURNS

Free Standard Delivery on UK Orders Over £50.00
UK Standard Delivery (5-7 working days) is £4.00
UK Next Day Delivery
is £6.00
Delivery to Guernsey & Isle of Man is £16.99

Delivery costs for shipments to other locations will be calculated at checkout.

Made for you

For more than 30 years, we’ve built nutritional systems that support your capability for years to come

Built for real progress

High-quality protein and carbohydrates work together to support your training, recovery and muscle-building goals. A complete solution for those looking to make every session count.

Everything you need. Nothing you don't.

Building strength takes consistency, not a cupboard full of products. This bundle brings together the essentials in one place, so you can spend less time planning and more time training.

QUALITY YOU CAN RELY ON

From our facility in Brighton, we’ve delivered the same high standards for more than two decades. We only believe in the highest grade minerals, so that's what we use.

What's inside

Bulk up Bundle

Frequently Asked Questions

What you need to know

Each 300g serving provides approximately 18 servings from the 5.4kg tub. Instant Mass Heavyweight is also available in a 2kg tub providing approximately 6 serving, a practical option for those trying the product for the first time before committing to the larger size.

Instant Mass® Heavyweight is designed specifically to help increase calorie and protein intake, making it suitable for people who want to gain weight. To gain body weight, you need to consistently consume more calories than your body uses; Instant Mass® Heavyweight can make achieving a calorie surplus more convenient.

Instant Mass® Heavyweight can complement a muscle-building diet by providing 60g of protein and a high calorie intake per serving. Protein contributes to the growth and maintenance of muscle mass, while resistance training and an appropriate overall diet remain important parts of a muscle-building programme.

Mix 300g with 700ml of water in a shaker cup or blender and mix until smooth. For precise measurements, using weighing scales is recommended as the scoops measure in millilitres rather than grams. The shake can also be mixed with skimmed milk to increase the calorie and protein content further, depending on your individual goals.

Reflex Nutrition Instant Mass Heavyweight is a premium mass gainer shake designed specifically for hard gainers and athletes who train intensely but struggle to consume enough calories and protein through food alone. Each serving provides a high amount of protein, carbohydrates, and calories.

Common signs of a zinc deficiency include frequent infections, slow wound healing, and a reduced sense of taste or smell. Consult a doctor if you experience any of the symptoms and want to find out whether a Zinc supplement would be the right choice for you.

Oysters have the highest amount of zinc per serving of any food, but many other animal and plant sources also provide this essential mineral. Red meat, crab and lobster, poultry and dairy and eggs offer moderate amounts.

As with all supplementation, please consult your doctor before commencing use of this product. This product is not to be used by persons with a pre-existing medical condition, or those taking medication. This product is not intended for use by persons under the age of 18.

This product is a dietary supplement and should be used in conjunction with food as part of a healthy balanced diet.

Yes, you have the right to cancel your order within 14 days from the date you receive your items, without needing to give a reason.

You have 14 days from the date of delivery to cancel your order under your cooling-off period rights. This allows you to change your mind about your purchase and return the item, provided it is unused and in its original, resellable condition.

To arrange a return or refund, please contact our Customer Service team via email on info@reflexnutrition.com or call 01273 303817 with your order number and delivery address, and we will guide you through the next steps.

Yes, return shipping is your responsibility to arrange and pay for.


If a delivery fails or you don't collect your parcel and it comes back to us, additional charges may apply.

Refunds go back to your original payment method once we've received and processed your return. Timings vary by payment provider; your bank or card issuer will confirm the exact date.

If there is an issue with your order, please contact our Customer Service team via email info@reflexnutrition.com or call 01273 303817 with your order number and delivery address as soon as possible so we can investigate and resolve the issue.

Items must be unused and in their original, resellable condition, exactly as you received them. Pack them securely in appropriate packaging to protect them in transit.


We can't accept returns that arrive damaged due to poor packaging.

We are unable to accept returns for certain items where it would not be suitable for resale, such as products that have been opened, used, or are not in a resellable condition.

If you no longer have your receipt or order confirmation, please contact our Customer Service team via email info@reflexnutrition.com or call 01273 303817 with as much information as possible (such as your name, email address, or delivery postcode), and we will do our best to locate your order.

Replacements or exchanges will be processed once your returned item has been received and inspected. Delivery times for replacements will follow standard shipping timeframes.

Yes, items purchased using a discount code or as part of a promotion can still be returned, provided they meet the returns criteria. This means items must be unused and in their original, resellable condition, exactly as you received them. Pack them securely in appropriate packaging to protect them in transit.

The Muscle Bomb Pre Workout is specifically designed to be mixed with water. The product description highlights "easy mixability and no clumps" for a smooth, convenient preparation.

The Muscle Bomb Pre Workout contains several amino acids:

•L-Tyrosine - Supports focus and mental performance

•L-Taurine - Helps with muscle function and endurance

•Beta-Alanine (2.5g) - Delays muscle fatigue by buffering lactic acid

•Citrulline (6g active from 9g Citrulline Malate) - Boosts nitric oxide production for improved blood flow and muscle pumps

The Muscle Bomb® is formulated to support energy, focus and training intensity. Caffeine contributes to increased alertness and improved concentration, while vitamins B6 and B12 contribute to the reduction of tiredness and fatigue.

The formula also contains ingredients commonly used in pre-workout products, including citrulline malate, beta-alanine, taurine and L-tyrosine.

The Muscle Bomb® is a high-caffeine pre-workout supplement designed to support energy, alertness, focus and high-intensity training. It combines caffeine with citrulline malate, beta-alanine, betaine, taurine, L-tyrosine, electrolytes and vitamins B6 and B12.

Blue Raspberry, Lemon Sherbet, Twizzle Lolly and Sour Apple

Our courier does not require a signature and will take a photo as proof of delivery. If no “safe place” or alternative delivery option has been selected, your parcel will be returned to the depot and reattempted the next working day. If the parcel is not redelivered or collected within 5 days, it will be returned to us and a charge may apply.

If your order arrives damaged or incorrect, please contact our Customer Service team as soon as possible with your order number, delivery address, and photos of the issue, so we can resolve this quickly.

If you believe your parcel is lost, please contact our Customer Service team with your order number and delivery address so we can investigate this with the courier.

If your order has not arrived within the expected timeframe, please check your tracking information first. If you still need help, please contact our Customer Service team quoting your order number and delivery address, and we will be happy to assist.

Once your order has been dispatched, it is not usually possible to change the delivery address. However, you may be able to update delivery preferences directly with the courier using your tracking details.

Once your order has been dispatched, you will receive an email from the courier with your tracking details and delivery updates.

Standard delivery typically takes 3–5 working days. Next working day delivery is available on eligible orders placed before 1pm Monday to Thursday.

We currently deliver within the UK, including Jersey, Guernsey, and the Isle of Man. Please note, we are unable to deliver to P.O. boxes or shipping agent addresses.

Yes, we offer free standard delivery on UK mainland orders over £50.

Standard UK mainland delivery is £4 for orders under £50, and free for orders £50 and over. Next working day UK mainland delivery is available for £6.

Zinc is an essential trace mineral that supports immune function, wound healing, cell growth, and protein synthesis in the body.