Optimum Nutrition
Optimum Nutrition | Serious Mass
Optimum Nutrition | Serious Mass
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High-Calorie Mass Gainer for Serious Size & Strength
Packed with 1,250+ calories, 50g protein, and 250g+ carbs per serving—designed to help hardgainers build muscle, recover faster, and bulk up effectively.
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The Ultimate Mass Gainer for Serious Gains!
When it’s time to pack on the muscle, Optimum Nutrition Serious Mass is the perfect solution. Whether you’re looking to bulk up or simply need to fuel your body with more calories, Serious Mass delivers an incredible 1,250 calories per serving to help you achieve your weight gain and muscle-building goals.
Key Features:
- 1,250 Calories per Serving: With 1,250 clean calories, Serious Mass gives you the energy and nutrition you need to gain mass without feeling overly full or sluggish.
- 50g of Protein per Serving: Each serving delivers 50 grams of premium protein to support muscle repair, growth, and recovery after intense workouts.
- Over 250g of Carbs: Packed with high-quality carbohydrates to fuel your workouts and replenish energy stores, ensuring sustained performance throughout your training sessions.
- Essential Nutrients: Includes a complete blend of vitamins, minerals, and amino acids that support overall health and muscle function.
- Creatine, Glutamine & Other Ingredients: Specially formulated with creatine, glutamine, and other ingredients to enhance strength, endurance, and muscle recovery.
Why Choose Optimum Nutrition Serious Mass?
- Perfect for Hard Gainers: If you struggle to gain weight or build muscle, Serious Mass is specifically designed to provide the extra calories and nutrients your body needs for effective weight gain and muscle growth.
- Quick & Convenient: Need a high-calorie boost between meals or post-workout? Serious Mass mixes easily and tastes great, giving you a hassle-free way to increase your daily caloric intake.
- Comprehensive Muscle Support: With its advanced formula, Serious Mass supports not only muscle growth but also strength, endurance, and overall recovery, making it the perfect choice for those looking to take their fitness to the next level.
Suggested Use: Mix 2 scoops of the powder into 24 fluid ounces of cold water or milk using an electric blender. This allows to you add in fruits, peanut butter and other calorie-contributing foods.
TIP: New users should start with a 1-scoop half serving. Use post-workout and/or between meals to add calories, carbs and protein to your healthy, balanced diet.
Product Benefits:
- Supports significant muscle gain and weight gain
- 1,250 calories per serving to help hard gainers bulk up
- 50g of high-quality protein per serving for muscle repair and growth
- Packed with 250g of carbs to fuel workouts and enhance performance
- Fortified with creatine, glutamine, and other essential nutrients for muscle recovery and strength
The Ultimate Mass Gainer for Serious Gains!
When it’s time to pack on the muscle, Optimum Nutrition Serious Mass is the perfect solution. Whether you’re looking to bulk up or simply need to fuel your body with more calories, Serious Mass delivers an incredible 1,250 calories per serving to help you achieve your weight gain and muscle-building goals.
Key Features:
- 1,250 Calories per Serving: With 1,250 clean calories, Serious Mass gives you the energy and nutrition you need to gain mass without feeling overly full or sluggish.
- 50g of Protein per Serving: Each serving delivers 50 grams of premium protein to support muscle repair, growth, and recovery after intense workouts.
- Over 250g of Carbs: Packed with high-quality carbohydrates to fuel your workouts and replenish energy stores, ensuring sustained performance throughout your training sessions.
- Essential Nutrients: Includes a complete blend of vitamins, minerals, and amino acids that support overall health and muscle function.
- Creatine, Glutamine & Other Ingredients: Specially formulated with creatine, glutamine, and other ingredients to enhance strength, endurance, and muscle recovery.
Why Choose Optimum Nutrition Serious Mass?
- Perfect for Hard Gainers: If you struggle to gain weight or build muscle, Serious Mass is specifically designed to provide the extra calories and nutrients your body needs for effective weight gain and muscle growth.
- Quick & Convenient: Need a high-calorie boost between meals or post-workout? Serious Mass mixes easily and tastes great, giving you a hassle-free way to increase your daily caloric intake.
- Comprehensive Muscle Support: With its advanced formula, Serious Mass supports not only muscle growth but also strength, endurance, and overall recovery, making it the perfect choice for those looking to take their fitness to the next level.
Suggested Use: Mix 2 scoops of the powder into 24 fluid ounces of cold water or milk using an electric blender. This allows to you add in fruits, peanut butter and other calorie-contributing foods.
TIP: New users should start with a 1-scoop half serving. Use post-workout and/or between meals to add calories, carbs and protein to your healthy, balanced diet.
Product Benefits:
- Supports significant muscle gain and weight gain
- 1,250 calories per serving to help hard gainers bulk up
- 50g of high-quality protein per serving for muscle repair and growth
- Packed with 250g of carbs to fuel workouts and enhance performance
- Fortified with creatine, glutamine, and other essential nutrients for muscle recovery and strength
⚡For Hard Gainers & Athletes – Ideal for those who struggle to gain weight & muscle
🔥Mass & Strength Formula – Supportsweight gain, muscle recovery & strength-building
🏆No Unnecessary Fillers – Premium ingredients tested & trusted by athletes worldwide
⚡For Hard Gainers & Athletes – Ideal for those who struggle to gain weight & muscle
🔥Mass & Strength Formula – Supportsweight gain, muscle recovery & strength-building
🏆No Unnecessary Fillers – Premium ingredients tested & trusted by athletes worldwide
Mix 2 scoops of the powder into 24 fluid ounces of cold water or milk using an electric blender. This allows to you add in fruits, peanut butter and other calorie-contributing foods.
TIP: New users should start with a 1-scoop half serving. Use post-workout and/or between meals to add calories, carbs and protein to your healthy, balanced diet.
Mix 2 scoops of the powder into 24 fluid ounces of cold water or milk using an electric blender. This allows to you add in fruits, peanut butter and other calorie-contributing foods.
TIP: New users should start with a 1-scoop half serving. Use post-workout and/or between meals to add calories, carbs and protein to your healthy, balanced diet.
ON’s Serious Mass is trusted by hardgainers around the world — and it’s built with clean bulking in mind.
✅ Tested for Banned Substances – Informed-Choice Certified
✅ High-Calorie, Nutrient-Dense Formula – Over 1,200 kcal per serving
✅ Quality Protein Sources – Whey, casein, egg for complete amino profile
✅ Produced in GMP-Certified Facilities
✅ ON Global Reputation – Backed by one of the world’s top sports nutrition brands
Every scoop is a step toward serious size — with serious quality behind it.
ON’s Serious Mass is trusted by hardgainers around the world — and it’s built with clean bulking in mind.
✅ Tested for Banned Substances – Informed-Choice Certified
✅ High-Calorie, Nutrient-Dense Formula – Over 1,200 kcal per serving
✅ Quality Protein Sources – Whey, casein, egg for complete amino profile
✅ Produced in GMP-Certified Facilities
✅ ON Global Reputation – Backed by one of the world’s top sports nutrition brands
Every scoop is a step toward serious size — with serious quality behind it.
Q: How many calories per serving?
A full serving (2 heaping scoops) provides ~1,250 calories with 50g of protein.
Q: Is it good for skinny guys trying to gain weight?
Yes — it's one of the best mass gainers available, ideal for hardgainers and those with high metabolisms.
Q: When should I take Serious Mass?
Post-workout and/or between meals are ideal times. Some even use half servings before bed.
Q: Can I mix it with water or milk?
Yes — mix with water for lighter texture, or milk for extra calories and creaminess. Blending with fruit or nut butter is also popular.
Q: Is it safe for teens or beginners?
Yes — as long as they meet general health standards. Always check with a healthcare provider for younger users.
Q: How many calories per serving?
A full serving (2 heaping scoops) provides ~1,250 calories with 50g of protein.
Q: Is it good for skinny guys trying to gain weight?
Yes — it's one of the best mass gainers available, ideal for hardgainers and those with high metabolisms.
Q: When should I take Serious Mass?
Post-workout and/or between meals are ideal times. Some even use half servings before bed.
Q: Can I mix it with water or milk?
Yes — mix with water for lighter texture, or milk for extra calories and creaminess. Blending with fruit or nut butter is also popular.
Q: Is it safe for teens or beginners?
Yes — as long as they meet general health standards. Always check with a healthcare provider for younger users.
I repeat: waste of money
serious mass is fr for serious mass
finishes so fast if taken 2 scoops per day
smooth n filling
c est bon mais sucre de ouf