When gaining weight is the mission, Optimum Nutrition Serious Mass delivers the firepower. Packed with high calories, quality carbs, and essential protein, this mass gainer is built for anyone who struggles to put on size or needs a heavy calorie boost to grow big and stay strong.
Why You’ll Love It
Massive calorie hit to help even the hardest gainers build size
Quality carbs and protein to support muscle recovery and growth
Perfect between meals or post-workout to boost total daily calories
Loaded formula designed to help you add real mass, not just sugar weight
If you’re ready to bulk with intent, Serious Mass gives you the nutritional support to grow bigger, stronger, and heavier—fast. 💪📈🔥
