Optimum Nutrition Serious Mass Weight Gainer, 12 lb bag, and Gold Standard Pre-Workout supplement, 330g container

Mass Stack XL

  • Serious Mass (12lbs): 1,250 calories, 50g protein, 252-254g of carbohydrates per serving
  • GOLD STANDARD® Pre-Workout (30 servings): 175mg caffeine, 3g creatine monohydrate, 1.5g beta-alanine per serving
  • Bookend workouts with the performance nutrition you want
Sale price$92.49
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1. These statements have not been evaluated by the food and drug administration. This product is not intended to diagnose, treat, cure or prevent any disease.
2. No significant difference has been shown between RBST treated and non-RBST treated cows.
3. When used over time in combination with regular resistance exercise.
4. Source Euromonitor International Limited; Consumer Health 2025 Edition, Sports Nutrition category, %retail value shares, 2024 data.
5. Not a low calorie food.
6. Naturally occurring amino acids.
7. See nutrition information for saturated fat, cholesterol and sodium content.