Optimum Nutrition (ON) is part of the Glanbia global nutrition group and has been setting the gold standard in sports nutrition for over 35 years. Today, ON’s range includes whey, casein and plant‑based proteins, weight gainers such as Serious Mass, ready‑to‑drink shakes, pre‑workout and intra‑workout formulas like Gold Standard Pre‑Workout and Essential Amino Energy, endurance and recovery supplements (including BCAA 5000 and glutamine), creatine powders, vitamins and active‑lifestyle essentials.