October 31, 2019

Wondering how much fluids and electrolytes you need during exercise? Mariella explains

water bottle fitness

We all know hydration is an important part of exercising, but it is often confusing and not well understood. Do we need to drink a sports drink at every session and what exactly are electrolytes? Our dietician Mariella gives us the answers and explains how to tell if you’re getting enough fluids and electrolytes, when exercising, whether you’re a serious athlete or doing a moderate amount of exercise.  

Hydration in athletes

Hydration, according to the dictionary, is the process of causing something to absorb water.

However, it is not just a matter of water. As individuals who exercise, hydration is also a matter of electrolytes. The scientific definition of electrolytes is rather complicated but to put into layman’s terms, electrolytes are substances that play a role in nutrient metabolism into our body’s cells, as well as waste removal. In other words they are needed for our body to function in many areas such as water balance and muscle contractions.

And of course, these areas are all very important when it comes to exercising and if we want to perform and get the most out of workouts.

So what do we need to look at when it comes to hydration? As mentioned, it is not only a matter of water, but also salts i.e. electrolytes.

A lack of those will cause dehydration, which can negatively affect our performance and make our lives very difficult. 

The reason we need to take in electrolytes is because when we exercise, we sweat and this causes a loss in electrolytes because our sweat is high in those salts. Everyone’s sweat is different, so the concentration of salts vary from person to person. There are scientific tests to determine your sweat rate and sweat composition to help you calculate exactly how much liquid you need to drink, but not everyone goes through the effort of going to get one of those tests done.

Genetics alone aren’t the only thing that affect sweat rate. It is also determined by external factors such as exercise duration, exercise intensity, the environment, like temperature and humidity, and whether you are acclimatized to the environment. All these factors will also affect how much you sweat.

How do I know if I am getting enough fluids?

There are some easy ways to track whether you are drinking enough fluids. Firstly, your urine colour is a good indicator. If your urine is a pale yellow you are probably well hydrated, but as soon as it starts getting darker, it may be an indicator that you should hydrate more. This is because when we are dehydrated, our body holds onto fluid, therefore making the urine more concentrated and hence, darker in colour.

Other signs of dehydration also are: dry mouth, thirst, headache, nausea, irritability or light headedness.

You can also track how often you go to the bathroom. If you have not urinated in a long time, then it is probably time to drink up.

Mariella is the registered dietitian at DayToDay. When not working alongside Chef Gino, she is giving talks on healthy eating and competing in triathlons.