Electrolytes in sport: isotonic or hypotonic drink?

Whether you're a beginner or a seasoned athlete, from Sunday jogging to triathlon, hydration is an important factor to consider in order to be in optimal shape during physical activity. In this article, we'll explore why exercise rhymes with hydration, as well as the different types of sports drinks. We'll then provide guidance on choosing the ideal beverage.

Why hydrate during physical exercise?

During physical exertion, we observe an increase in body temperature. To prevent our bodies from overheating, temperature regulation is put in place. To lower this temperature, our bodies sweat. This then leads to a loss of water and mineral salts (or electrolytes) such as sodium, potassium, magnesium, and calcium.           

Sweating then leads to dehydration, which is characterized by a lack of electrolytes due to an imbalance between water intake and loss. Indeed, electrolytes are essential for athletes because they contribute to proper hydration, muscle contraction, and the transport of nerve signals from the brain to the muscles. Therefore, a deficiency in one or more of these electrolytes has repercussions on the body's functioning, particularly during physical activity.

Magnesium contributes to muscle relaxation after contraction and therefore helps combat cramps following physical exertion.

Potassium, for its part, plays a role in nerve signal transmission and muscle contraction. It also has alkalizing properties, meaning it fights acidity, particularly lactic acid produced during exercise. Lactic acid is the main factor contributing to the onset of muscle cramps.

Many athletes regularly eat bananas because they are one of the fruits containing the most magnesium and potassium, and therefore help prevent cramps and muscle aches.

Regarding intake, it is considered that you should drink 0.5 liters of electrolyte-containing beverages for every hour of exercise. If the physical activity lasts less than an hour, water alone is sufficient.

What do “isotonic” and “hypotonic” mean?

These terms are used to describe the difference in concentration between compounds in the blood and those in the drink. Isotonicity is when the proportions of substances in the blood and the drink are identical. A hypotonic drink, on the other hand, has lower concentrations of solutes than in the blood.

There are also hypertonic drinks , also called energy drinks because they contain a lot of sugars and thus provide energy to the body.

However, hypertonic drinks reduce the rate of water absorption because the concentration of solutes being higher, there is first a step of dilution of the drink thanks to the water present in the blood, which leads to temporary dehydration. It is once diluted that the water and electrolytes can then be absorbed by the body. Therefore, hypertonic drinks can be used in particular conditions, particularly during efforts of more than 60 minutes for which the need for hydration is low, for example in cold weather because perspiration is less and therefore dehydration is less.

How to choose the right sports drink?

A A hypotonic drink helps to replenish water and electrolyte losses more than sugar losses. An isotonic drink, on the other hand, replenishes water, mineral salts and sugar losses to an equivalent extent.

The drink should be chosen according to the planned effort. Indeed, an isotonic drink promotes the intake of water and electrolytes to compensate for losses caused by perspiration during sports. They are therefore used for sports of effort and endurance such as during a triathlon or a marathon because there is a greater risk of dehydration.

Hypotonic drinks are used when the goal is hydration rather than energy, as they contain very little sugar. They allow for faster water absorption and hydration. They are ideal for recreational sports or shorter or less strenuous workouts.

However, the drink must also be chosen according to your body's needs. Thus, if during exercise you experience gastric discomfort, the drink is too concentrated and you should therefore opt for a rather isotonic or hypotonic drink. On the contrary, if during exercise you feel the urge to urinate more quickly than usual, this means that the water has been absorbed too quickly and then eliminated, so you should switch to a more concentrated drink which leads to a slower and more gradual assimilation of water.

Hydratis is the solution to your problems. Hydratis lozenges allow you to make your own sports drink based on your needs and your body.

One lozenge in 500ml of water makes a hypotonic drink. It is also possible to have an isotonic drink with two lozenges in the same volume of water (500ml).

Hydratis lozenges are enriched with mineral salts (sodium, potassium, magnesium, zinc, and manganese) and help cover losses during exercise. They are also a source of energy thanks to their carbohydrate (sucrose) content. Hydratis has thousands of customer reviews that have helped optimize their daily hydration.

In conclusion, a hypotonic drink is therefore less concentrated than an isotonic drink. To choose the ideal drink, you must take into account the effort made during physical exercise and the losses it causes. It is also important to recognize your body's needs and adapt accordingly in order to be in optimal shape.

Find Hydratis on social media!