Q. Why should I bother with energy drinks? I know that I need to keep hydrated during training and racing, but isnt water good enough?A. As you run, two things happen: (1) you lose water as your body uses it to cool down and (2) you use muscle carbohydrate reserves to fuel your movement. During and after very short runs in cool conditions you need not take an energy drink. Drinking water after training should be enough to restore the fluids lost through sweat, while food eaten in the 24 hours following your effort should restore the carb stores in your muscles.
You need energy drinks if you train hard or long on a regular basis, or in warm conditions (hot weather, treadmills in gyms). Water alone is far less effective at rehydrating than an energy drink containing electrolytes (body salts). High-intensity training and long, slow runs can even be improved by using a carbohydrate-based energy drink during and after the session.
Aim for 400-700ml of energy drink per hour of exercise. Drink 400ml in the 30-60 minutes before training to ensure that youre properly hydrated before you start. Once youre running, sip 150-200ml every 15 minutes. If youre still thirsty afterwards, or failed to drink during the session, another 400-800ml may be required.
Joe Beer, sports scientist and level-two triathlon coach