Optimum Nutrition Serious Mass

Struggling to gain size? Optimum Nutrition Serious Mass is the ultimate weight gainer, packed with calories, protein, and carbs to help you put on size and strength. With over 1,250 calories per serve, plus added creatine, glutamine, and vitamins, it’s the smart way to hit your calorie surplus and fuel recovery. And because it’s Informed-Choice certified, every batch is tested for banned substances — safe for athletes and trusted worldwide.

Why Choose Serious Mass?

• 1,250+ calories per serve – the easiest way to hit your calorie surplus.

• 50g of protein – supports muscle repair and growth.

• 250g+ of carbs – replenishes glycogen and drives recovery.

• Added creatine & glutamine – for strength, recovery, and immune support.

• 25+ vitamins & minerals – helps cover daily nutrition needs.

• Informed-Choice certified – tested for banned substances, trusted by athletes.

• From Optimum Nutrition – the world’s #1 sports nutrition brand.

How to Use

1. Mix 2 heaped scoops of Serious Mass with 700ml–1L of water or milk.

2. Blend for best texture, add fruit, nut butter, or oats for extra calories.

3. Take post-workout and/or between meals to increase daily calorie intake.

Pro tip: Start with half a serve if you’re new to mass gainers, then build up as your body adjusts.

Who’s It For?

• Hard gainers who struggle to put on weight.

• Athletes needing a high-calorie recovery shake.

• Busy professionals who can’t always eat enough during the day.

• Drug-tested athletes wanting a safe, certified weight gainer.

FAQ

Is Serious Mass safe for athletes?
Yes — it is Informed-Choice certified, meaning it’s tested for banned substances and manufactured in a registered facility.

How many servings per day should I take?
Most users take 1 serve daily, but you can increase to 2–3 smaller serves depending on calorie needs.

Can I use it as a meal replacement?
Yes — it’s calorie-dense with protein, carbs, and added nutrients, making it suitable as a high-calorie meal replacement.

Why Buy from Sprint Fit?

• 100% authentic Optimum Nutrition supplements.

• Free NZ shipping on orders $60+.

• Same-day dispatch nationwide.

• Trusted by Kiwi athletes and fitness enthusiasts.

Optimum Nutrition Serious Mass – the ultimate weight gainer for size, strength, and recovery.

Available Sizes:
Container Size: 2.7KG (6Lb)
Serving Size: 2 Scoop (336g)
Servings Per Container:8

Container Size: 5.44KG (12Lb)
Serving Size: 2 Scoop (336g)
Servings Per Container: 16

Please Note: Nutritional Information is to be used as a guide only, actual values may differ between flavours and sizes and when formulations are modified or updated by the manufacturer. 
Contact us if you have any questions regarding this products ingredients.

All orders $60 and over receive Free* Shipping Nationwide 

Final pick up each day is at 3.45pm Monday to Friday. 

Estimated Delivery Times*:

Auckland and North Island – Overnight

However many Auckland orders will be delivered the same day depending on what time the order is placed)

South Island – Overnight (For larger parcels allow 2 business days)

Same Day/Evening Express Shipping upgrade available at checkout for select suburbs*

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