According to Nick Hudson, national fitness manager for Virgin Active, sports drinks won't give you any more energy to help you exercise harder - not unless you plan on spending half the day at the gym, that is.
What they do give you, however, is lots of added calories in the form of carbohydrate such as glucose - which means any calories you burn while you're working out are just being replaced by the energy drink. Why? Because your body should already have enough glucose to provide enough energy to keep going for up to two hours. So you don't need to top up with an energy drink after all.
It doesn't mean you shouldn't drink anything while you're pounding away on the treadmill or sweating up a storm in spinning class. If you bypass any form of liquid refreshment you could end up dehydrated. Many experts suggest the best thing to drink for a relatively short workout is water - or if you prefer the taste of energy drinks, choose a low-calorie version.
What are your tips for getting the most out of your workout?