Everything you need to know about hypertonic drinks: what are they really used for?

What is a hypertonic drink?

A hypertonic drink has a higher concentration of dissolved solutes (sugars and electrolytes ) than blood. It draws less concentrated water from your body through osmosis. As a result, water from the bloodstream is absorbed through the intestines. This slows down the body's absorption of water, leading to temporary dehydration . This drink contains high levels of carbohydrates and minerals to replace those used during prolonged intense exercise.

Difference between hypertonic, isotonic and hypotonic drink

A hypotonic drink contains low amounts of sugars and electrolytes compared to blood, this maximizes the assimilation of water into the bloodstream, and therefore rehydration . This solution is suitable for athletes who need to hydrate without a large carbohydrate intake and is less well absorbed than an isotonic solution but it can be useful in case of high heat.

An isotonic drink contains particles in quantities similar to those present in your body, allowing for consistent absorption. It's a good compromise between hydration and energy.

A hypertonic drink, on the other hand, contains particles in greater quantities than blood. It provides a lot of energy , but is less effective for rapid hydration.

The benefits of different types of drinks:

How do hypertonic sports drinks work?

Hypertonic sports drinks contain a high carbohydrate and electrolyte content. They are typically consumed after prolonged, intense exercise ( such as marathons and triathlons ) to replenish muscle glycogen stores. Their high carbohydrate concentration can make them difficult to absorb during sustained exercise. However, they can be used as “fuel” before exercise.

Hypertonic drinks can be made up of simple sugars (glucose and fructose) and complex sugars (maltodextrin) for a rapid and prolonged release of energy. Before exercising, you should therefore remember to hydrate well if you use hypertonic solutions!

Hypertonic solutions are less well absorbed than isotonic solutions. They are therefore not effective for rapid hydration during prolonged exercise, especially in high heat.

If consumed during intense exercise, hypertonic solutions can slow gastric emptying and cause digestive disturbances, such as bloating and cramps .

When should you use a hypertonic drink?

Before a long effort, to “recharge” with carbohydrates

A hypertonic solution can be consumed in the days before a marathon, triathlon, or any other prolonged endurance exercise. It helps replenish muscle glycogen stores, which improves performance and delays the onset of fatigue . It is therefore important to allow sufficient time before starting the sport to avoid digestive problems.

After intense exercise, to replenish energy reserves

Hypertonic solutions are particularly recommended in the hours following prolonged and intense exercise. They help to quickly replenish energy reserves and promote recovery by providing essential sugars and minerals.

Drink not recommended for short efforts or in very hot weather

It is best to avoid hypertonic solutions during exercise, especially in hot weather or during short-term activity. Their high solute content slows water absorption and can lead to digestive problems. In these situations, and depending on the temperature, isotonic or hypotonic drinks are more suitable for ensuring rapid and effective hydration.

Advantages and disadvantages of hypertonic drinks

Benefits

• Rapid energy recharge: thanks to their high carbohydrate content, they allow rapid replenishment of glycogen reserves after physical exertion.
  

• Electrolyte intake (including sodium): electrolyte intake helps compensate for losses due to perspiration, particularly after prolonged exercise.

Disadvantages

• Poorly hydrating: Due to their high mineral concentration, they are absorbed more slowly than isotonic and hypotonic solutions. They are therefore less effective for rapid hydration.
  

• Can cause digestive problems if misused: in fact, if consumed during intense activity, they can cause digestive problems such as stomach aches and bloating.

FAQ – Answers to the most frequently asked questions

What is a hypertonic drink?

This is a solution with a higher particle content (sugars and electrolytes) than blood. It is less effective for rapid hydration and provides significant energy gains.

What is the difference between hypertonic, isotonic and hypotonic drinks?

A hypertonic drink has a higher particle content than blood, making it less effective for rapid hydration and very energy-dense. An isotonic drink has a solute concentration similar to that of blood, providing a good balance between hydration and energy. A hypotonic drink contains fewer particles than blood, maximizing rehydration and being low in energy.

When should you drink a hypertonic drink?

A hypertonic drink can be consumed before prolonged exercise to optimize athletic performance, or afterward to allow for better recovery. Avoid during physical activity or in extreme heat.

Should hypertonic drinks be included in your sports practice?

Incorporating hypertonic solutions into your sports practice depends on the activity, its duration, and its intensity. They are useful for intense and prolonged efforts, allowing you to maintain good energy. To choose the ideal drink, it is necessary to understand your hydration and energy needs . However, they can cause digestive problems if used incorrectly. Amateur athletes can hydrate with water alone, or even with isotonic solutions. Hypertonic drinks are therefore not essential for all sports practices.

Bibliography

Ashurst, P.R., & Hargitt, R. (2009). Product development of new soft drinks and fruit juices. In Elsevier eBooks (pp. 1‑19). https://www.sciencedirect.com/science/article/abs/pii/B9781845693268500013 

Skarlovnik, T., La mut, A., Hostnik, G., Gole, B., & Bren, U. (2024). Osmolality and Tonicity of Isotonic Beverages. Foods (Basel, Switzerland), 13(10), 1483. https://doi.org/10.3390/foods13101483   

Raizel, R., Coqueiro, AY, Bonvini, A., & Tirapegui, J. (2019). Sports and Energy Drinks: Aspects to Consider. In Elsevier eBooks (pp. 1‑37). https://doi.org/10.1016/b978-0-12-815851-7.00001-2