An isotonic drink is essentially just water and glucose (sugar) with some added vitamins and minerals. Perhaps the most popular type of such beverage is Lucozade Sport but there are now dozens of similar drinks on sale in the UK.
In recent years, isotonic drinks have sprung up all over the place promising to boost your physical performance and help your body recover from physical exertion. But are these claims based in scientific fact?
When we exercise, many of the minerals contained in our body are either burnt up or excreted through perspiration. Isotonic drinks help replenish these lost minerals as well as topping up our energy levels. The theory is, that you will therefore recover more quickly from a workout or a sporting activity.
And, in fact, you actually will... to an extent. The glucose will give you an energy boost, and the 4 to 8% carbohydrate content typically found in such drinks can improve your stamina. The added sodium contained in most energy drinks is also beneficial as it enhances fluid absorption.
However, despite their price, isotonic drinks are in no way superior to regular food. They don't contain any magical ingredients or special formula. A glass of water and a banana are every bit as beneficial to your body, if not more so.
Isotonic drinks are by no means bad for you. Their practicality can, in some instances, make them a better choice than water and a selection of fruit. Just don't expect them to transform your energy or stamina levels.
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