Big Mass Gainer GSN is a shake created especially for gaining muscle and weight. It combines carbs and amino acids to encourage the growth of muscle. With added creatine, it provides 3 grams of pure creatine daily. It contributes to the preservation and growth of muscle mass because it contains more than 80% whey protein. You can consume more calories thanks to its high-calorie formula, which provides 1351 calories each day.