• optimum nutrition serious mass weight gainer protein powder
• High Protein Muscle Building & Weight Gain Formula*
• 50 g Protein^* - Helps Build and Maintain Muscle*
• 1,260 Calories - Helps Boost Calorie Intake
• 251 g Carbs - Helps Fuel Intense Workouts
• Artificially Flavored
• Protein Powder Supplement
• Strength Training
• Supports Performance
• Supports Weight Gain Goals*
• Authentic Optimum Nutrition Product
• Informed Choice, We Test You Trust
• Regularly Tested For Banned Substances

Serious Mass™ is designed to provide SERIOUS calories, protein and carbohydrates - making this a convenient way to get extra calories throughout your day.

A Global Leader of Weight Gainers

SERIOUS weight gain requires SERIOUS calories. However, those who need the extra calories most often have the toughest time consuming enough of them. For many aspiring to be bigger, having a highly-active metabolism, weaker appetite or an on-the-run lifestyle can make it a real challenge to consume enough calories through whole foods alone. With SERIOUS MASS™, you've got nothing to lose and lots to gain. It's time to stop thinking small; get SERIOUS - SERIOUS MASS™.

Why Serious Mass™?

• 50 g of protein to support muscle building and recovery*
• 1,260 calories to support calorie surplus for weight and muscle building*
• 251 g of carbohydrate to support fueling of intense workouts and aid in replenishment of glycogen stores
• 5 g of creatine monohydrate to support strength, power, and performance*
• Naturally Occurring Glutamine 8 g, Branched Chain Amino Acids 11 g and Essential Amino Acids 24 g
• Good source of 19 vitamins and minerals
• Vitamins A, C, E, and zinc help support a healthy immune system
• B vitamins help convert food to cellular energy

Optimum Nutrition® has been trusted to provide the highest quality in post-workout recovery, pre-workout energy, and on-the-go sports nutrition for over 30 years and in 90+ countries. After careful supplier selection, each ingredient is tested to assure exceptional purity, potency and composition. We hold ourselves to the highest production standards, all so you can unlock your body's full potential. 

*When taken in addition to normal calorie intake and regular weight resistance training

^¦See supplement facts for sodium and cholesterol content.