Serious Mass

Optimum Nutrition Serious Mass is a high calorie, high protein formula designed to help you increase strength and pack on muscle.

With over 1250 calories and 50 grams of protein per 324g serving even the hardest gainers will be sure to put on size when combined with a proper training program.

Serious Mass also contains Creatine and Glutamine as well as 25 vitamins and essential minerals to help improve recovery after serious training sessions. These compounds increase blood flow to muscle cells, making them appear larger and more vascular.