Optimum Nutrition's Serious Mass is the ultimate weight gain formula. With 1,250 calories per serving and 50 grams of protein for muscle recovery, this instantised powder makes for a sizeable post-workout and between-meals shake. Optimum Nutrition's Serious Mass’ protein blend provides easy-to-digest protein, boosting your muscle protein
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I just use the one scoop and its so thick but its worth it if you wanna bulk up
