High 5 Zero X'Treme Hydration (single tube) Zero the new great tasting electrolyte drink from High5, now comes with a caffeine kick (65mg) - about the same as a mild cup of coffee. It's virtually calorie free (1.4 calories per 100 ml) and is designed for optimal hydration both during and after exercise and to provide a stimulant boost when you are flagging to help focus, and concentration. X'treme is also a great way to get hydrated and give you a boost before a session when you are tired and don't feel up to it. X'treme is easy to use, drop a tablet in your bottle and it quickly dissolves in water to give you a delicious, refreshing, advanced electrolyte drink with added magnesium and stimulants. X'treme can be an essential part of your anti cramp strategy as cramp has been linked to both dehydration and electrolyte imbalance. X'treme contains; sodium, potassium, magnesium and calcium. Zero X'treme is perfect for runners, cyclists, hikers, the gym, pro athletes, footballers, racket sports or anyone who wants to stay active, alert, focused and hydrated.