ULTRA energy drink, how to choose?
When you determine what nutrition and hydration you are going to adopt on the UTMB®, the choice of an isotonic drink will be important to make, well in advance of the event. Here is some information that can guide you in selecting your isotonic drink and acclimatise easily.
What is an isotonic drink?
The term isotonic drink refers to the osmolarity, or tonicity, of a drink. Osmolarity is measured in mOsm per litre of solute or mOsm/L, and this counts the amount of osmotically active particles in a solution, and in particular quantifies sodium and glucose. The reference basis for comparing the osmolarity of a solution is that of plasma, which ranges from 275 to 300 mOsm/L: a drink is said to be isotonic when its osmolarity is close to that of plasma, hypotonic when it is lower and hypertonic when it is higher. This notion is essential in the context of hydration because when two solutions separated by a permeable membrane whose osmotically active particles are identical in each of the two solutions, then the movement of water and the transfer of particles will be optimal. Conversely, a hypotonic solution will absorb particles from the blood plasma and a hypertonic solution will enrich the plasma too much.
Selecting an isotonic drink
An isotonic drink, to put it simply, is a drink enriched and perfectly dosed with mineral salts and carbohydrates: two nutrients that are essential in running and in sport in general. These drinks are available in bottles with the mixture already made, or in tablets or powder to be mixed in water. There is no better solution, the main criterion of choice lies in the taste and your ability to accept this drink without impacting your digestion. In short, you choose the one you like best. There are also salty-tasting ones, for those who are quickly fed up with the sweet taste. It is of course important to test your isotonic drink during your preparation. Make sure that you assimilate it well during your training sessions and that the taste does not become too unpalatable over time. Some brands develop different flavours for this purpose: it can be clever to have drinks with different flavours but with the same recipe and the same brand. Also make sure you always have water with you and alternate from time to time. Unpleasant sensations after a while are pasty saliva or stomach ache. After tens of kilometres in the mountains, this is not recommended, so carry out numerous tests and change as soon as you feel that a drink does not suit you. For drinks to be made with powder, be careful to respect the recommended dosage, otherwise your drink will never be isotonic and will have little beneficial effect during exercise.