Serious Mass 5.45 Kg from Optimum Nutrition is the global reference in supplements designed for massive weight and muscle mass gain. This gainer is perfect for people with fast metabolisms or high-performance athletes who struggle to gain volume with just a conventional diet. Each shake provides an amazing caloric density, exceeding 1250 calories per serving, thanks to its combination of complex carbohydrates and quality proteins, including whey concentrate, calcium caseinate, and egg albumin. This ensures not only an immediate release of amino acids but also sustained release, essential for muscle recovery after intense workouts. Additionally, Serious Mass is enriched with creatine monohydrate, glutamine, and 25 vitamins and minerals that maximize strength and recovery, providing comprehensive nutritional support. This 5.45 Kg savings format is ideal for prolonged bulking phases. Its excellent solubility and variety of flavors make it the ultimate tool for transforming your physique and achieving weight goals that once seemed unattainable.