Serious Mass 5.45 Kg from Optimum Nutrition is globally recognized as an essential supplement for weight gain and muscle mass. This gainer is specially designed for those with fast metabolism and athletes with high energy demands, facilitating the calorie surplus essential for growth. Each shake provides over 1250 calories from complex carbohydrates and a blend of high-quality proteins, including whey concentrate, calcium caseinate, and egg albumin. These components offer both immediate and sustained amino acid release, crucial for muscle recovery after intense workouts. Additionally, it contains creatine monohydrate, glutamine, and a mix of 25 vitamins and minerals, providing comprehensive support for strength and well-being. Its excellent solubility and classic flavors such as strawberry, banana, chocolate-peanut, and cookies and cream make it appealing and practical. It is ideal for consumption between meals or before bedtime to ensure a constant anabolic state throughout the day. Regardless of weight goals, Serious Mass is the ultimate tool for those needing extended calorie support.