Whats the difference between hypotonic, isotonic and hypertonic drinks?
A hypotonic drink is more dilute than your body fluids (ie there are fewer particles – sugars/electrolytes per 100ml), which means that it can be absorbed faster than plain water. For example, squash diluted at least 1:8 with water, or one part fruit juice diluted with three parts water. Isotonic means it is the same concentration (ie the same number of particles per 100ml) as your body fluids – it is therefore absorbed as fast as or faster than water. They provide an ideal compromise between rehydration and refuelling. For example, Isostar, Lucozade Sport or fruit juice diluted half and half with water or squash diluted 1:4 with water. Hypertonic drinks, such as cola, lemonade or neat fruit juice, are more concentrated than body fluids, and will be absorbed more slowly than plain water. Hypertonic drinks slow down the rate at which the stomach empties and therefore reduce the speed of fluid replacement. These are better post-run drinks that offer a higher dose of energy with the fluid
