Serious Mass Chocolate 1.34kg
by Optimum Nutrition
Optimum Nutrition Serious Mass is a long-standing, high-calorie mass gainer delivering 1,250 kcal, 50 g protein and over 250 g carbohydrates per full serving, designed for hard gainers and strength athletes in a caloric surplus. Best for Hard gainers and ectomorphs struggling to reach caloric surplus through food alone and Strength and power athletes (weightlifting, rugby, football) needing rapid calorie and glycogen replenishment.
According to the AIScored 0–100 scoring system, Serious Mass Chocolate 1.34kg by Optimum Nutrition scores 62.0/100, ranking #22 out of 23 products in Mass Gainers (2026). Strongest category: Effectiveness (73.0/100). Weakest: Certifications (28.0/100).
Is Serious Mass Chocolate 1.34kg worth buying?
“Serious Mass scores 62.0/100 and delivers 1,250 calories per serving with a genuine 50g multi-source protein blend, making it properly effective for hard gainers who combine it with consistent training and calorie surplus. The included 3g creatine monohydrate per serving is a useful addition that saves buying a separate supplement, though this is really built for serious strength athletes rather than casual gym-goers watching their calorie intake.”
What Do Reviewers Say About Serious Mass Chocolate 1.34kg?
Sample excerpts from currently available source material used in this product analysis.
"Have this product on subscribe and save so only recently opened my most recent delivery, and there is next to no flavour, never had this issue before, but with this bag it taste horrible"
"I only use this brand of mass gainer… reason being it sits will in my digestive system, it definitely does what it supposed to do. I have used other brands, cheaper brands but they do not pack the punch this do 💪 I have literally been buyin..."
"It's helping me put on weight. I added a tablespoon of peanut butter and a banana, tastes really good with the strawberry one. This seems to be the best mass gainer, I've looked around and this is always said to be the best with approved in..."
"I don’t use this protein for the gym I use it cos I struggle to eat normal food and so this sometimes becomes my only source of food and with 1250 calories per shake I know if I drink 2 a day I’ll get all the nutrients I need infact probabl..."
"This protein powder is an excellent for anyone serious about gaining mass. The large size offers fantastic value, and the mix is effective and potent. It mixes well, taste good and is essential for hitting those high-calorie and high-protei..."
How does Serious Mass Chocolate 1.34kg score?
Detailed score breakdown and key findings from our analysis of 11 reviews across 2 sources.
Pros
- +Proven calorie density — 1,250 kcal per serving supports genuine weight gain when combined with training
- +50 g multi-source protein blend (whey, casein, egg albumin) supports muscle repair and sustained amino acid release
- +3 g added creatine monohydrate per serving provides a meaningful ergogenic dose without a separate supplement
- +Long-standing brand credibility — Optimum Nutrition is one of the most trusted names in sports nutrition
- +Palatability is generally rated well; chocolate and strawberry flavours receive positive feedback from most reviewers
Cons
- -Carbohydrates are primarily maltodextrin — a fast-digesting, high-GI source not suitable for those monitoring blood sugar or seeking higher-quality carbs
- -Digestive issues (bloating, excess gas) reported by a meaningful minority; very large serving size (334 g) can overwhelm digestive tolerance
- -Clumps without a blender and won't fit most standard shaker bottles — requires dedicated blending equipment
- -Not third-party tested (no Informed Sport / NSF certification), which is a concern for tested athletes or those prioritising label accuracy assurance
Best For
Watch Out
- !Multiple allergens: milk, egg, gluten, wheat; may contain peanuts and soy — unsuitable for those with relevant intolerances or allergies
- !Batch-to-batch flavour inconsistency reported by at least one long-term subscriber — quality control can vary
- !Full serving (334 g / 1,250 kcal) is very large; most users should start with a half-serving to assess digestive tolerance
- !High maltodextrin content makes this unsuitable for diabetics or those managing insulin sensitivity
What is Serious Mass Chocolate 1.34kg?
Serious Mass Chocolate 1.34kg is a mass gainers product by Optimum Nutrition in powder form, scoring 62.0/100 on AIScored.
- • Product Overview: A performance‑focused weight‑gain formula delivering 1,250 calories, over 250 g carbohydrates, 50 g protein and 3 g added creatine per serving, formulated to support muscle building, recovery and on‑going training performance.
- • Performance Benefits: 1,250 calories per serving — helps boost calorie intake.
- • 50 g protein per serving — helps build and maintain muscle.
- • Over 250 g carbohydrates per serving — helps support muscle recovery.
- • 3 g added creatine per serving — supports performance.
- • Active Ingredients That Matter: 50 g high‑quality protein per serving to support muscle building and repair; over 250 g carbohydrates for glycogen replenishment and recovery; 3 g added creatine per serving to support performance and short‑term high‑intensity exercise; 1,250 kcal boosts daily energy intake.
- • How To Use: Add 334 g (approximately two heaped scoops) to a blender filled with 710 ml of water.
- • Blend for 30–45 seconds.
- • Store in a cool, dry place.
- • Best Suited For For strength athletes and highly active individuals seeking a high‑calorie, high‑protein formula to support weight gain and intensive training recovery.
- • Always read the label.
- • This is an AI assisted summary.
Is Serious Mass Chocolate 1.34kg Independently Tested?
No Third-Party Testing Visible
We could not find evidence of independent third-party testing for this product. This doesn't mean it's unsafe, but independent verification provides additional assurance.
How We Score Supplements
Our methodology analyses review data, ingredient science, and product information, then scores each product on a 0-100 scale across evidence-based categories:
Effectiveness
How well the product delivers its claimed benefits, based on reviews and ingredient evidence.
Ingredient Quality
Bioavailable forms, clinically effective dosages, clean label, minimal fillers.
Value for Money
Price relative to ingredient quality, dosage count, and effectiveness.
Side Effects Profile
Higher score = fewer side effects. 100 means virtually no adverse reactions reported.
Certifications & Testing
Third-party lab testing, GMP certification, and independent quality verification.
Overall Score
Weighted combination of all factors. Our bottom-line recommendation.
How Does Serious Mass Chocolate 1.34kg Compare?
See how this product stacks up against the top-rated mass gainers in our database.
| Product | Score | Price |
|---|---|---|
| Serious Mass Chocolate 1.34kg (this) | 62.0 | £21.00 |
| Critical Mass Professional Lean ... | 80.0 | £40.00 |
Price History (90 days)
Quick Facts
- Form
- Powder
- Serving
- 100 g, 334 g
- Vegan
- No
Frequently Asked Questions
Is Serious Mass Chocolate 1.34kg worth buying in 2026? ▼
What is the best price for Serious Mass Chocolate 1.34kg in the UK? ▼
What are the pros and cons of Serious Mass Chocolate 1.34kg? ▼
Is Serious Mass Chocolate 1.34kg third-party tested? ▼
How does Serious Mass Chocolate 1.34kg compare to Critical Mass Professional Lean Mass Gainer Banana 2.4kg (16 Servings)? ▼
Disclaimer: AIScored provides research-backed summaries based on publicly available reviews and product information. This is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Affiliate links may earn us a commission at no extra cost to you.
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