Differences between hypotonic, isotonic and hypertonic drinks. Let’s be clear

What are the differences between hypotonic, isotonic and hypertonic drinks?
A few weeks ago, KEFORMA launched a file New hypotonic saline supplement It made us think about the advisability of conducting an in-depth study on this issue.
This is a very important topic, and there is still some confusion about it among athletes, not just cyclists.

What is the main difference? Is there one solution better than the other? When is the anti-stress drink most appropriate? When can it be beneficial to take an isotonic or hypertonic drug?

In this episode of Our column on integration We have answered these and other questions thanks to the usual help of Dr. Alexandre Bertuccioli.

Dr. Bertuccioli, surgeon, biological nutritionist and kinesiologist for protective and conditioning motor activity

What is the main difference between hypotonic, isotonic and hypertonic drinks?
Without going into unnecessary details, the The difference lies in the amount of solutes in the drink (which are defined in the technical field as solutions, i.e. the combination of a “solvent”, water, and one or more “solvents”, eg metal salts).

When we talk about drinks, human plasma is taken as a reference, that is, the liquid part of the blood that contains one Concentration of about 300 mOsm/L.
An isotonic drink has the same concentration of solutes, a hypotonic drink has a lower level and a hypertonic drink has a higher level.

Differences between low-stress drinks
picture Elite cycling

What are the advantages and “disadvantages” of the three types of solutions?
– I don’t think we can talk about strengths and weaknesses, but about the different uses that each type of drink can have.
To simplify the concept, a hypotonic drink favors the absorption of the liquid part by recalling the minimum amount of solutes in the intestine.
On the other hand, a hypertonic drink favors the absorption of solutes, but tends to call up fluids in the intestine (from which Osmotic diarrhea Because of hypertonic drinks, a big problem if they happen in competition or in training).
An isotonic drink represents the middle ground between the other two states.
Therefore, each solution can be used for a different function based on these properties.

Can the three types be useful at different times?
– exactly. During intense physical activity, taking into account fluid loss and the average dissolved content lost with sweating (about 3 g / l) Low tension solutions are the most appropriate In favor of fluid absorption while still providing the amount of solutes actually lost and reducing the risk of digestive disorders.
Remember that the most substances that are lost with sweating are seen in the first place chloridethen sodiumfollowed by potassium. Only after that we find magnesium, iron and zinc to a minimum.

Differences between low-stress drinks

On the other hand, when the activity ends and fluid withdrawal into the intestines rarely causes osmotic diarrhea problems that are difficult to manage, a hypertonic drink may be appropriate to enhance Faster recovery of lost itemsThis, however, is once sufficient fluid consumption has already occurred.

An isotonic drink is the solution for every day or for those workouts where intensity and duration aren’t an issue.

Why are low tension solutions more appropriate during intense efforts?
– As already mentioned, in Course of action Low-stress drinks are more beneficial, because they facilitate fluid absorption, save the amount of substances already lost with sweating and above all Demonstrate maximum gastrointestinal endurance.

Differences between low-stress drinks

Intestinal tolerance is one of the most important issues, with a drink in concentration (also known as ‘tone’ or osmolarity) Excessive, extremist, reckless It will have the opposite effect: first of all it hinders hydration and thus performance, but above all It impairs the full function of the intestines.
Drinking a hypertonic drink during activity forces the intestines to withdraw water. In the best case it leads to swelling and pain (colic) making it somewhat difficult to continue, and in the worst case to true diarrheal discharge, which are fairly frequent bouts during poorly managed races from a hydration point of view.

To summarize, in the course of work, low-stress drinks are the most useful and safe, even considering Frequent consumption of foods containing carbohydrates (bars, gels) or energy drinks, which are not an ideal combination with isotonic drinks (an isotonic drink + carbohydrates can mean hypertonic content in the digestive tract) and above all hypertonic.

Why is it important to respect the recommended doses?
– specifically in order not to prejudice the functionality we have just described.
By making a hydrating drink with less water than recommended, we make it, as the case may be, iso or hypertonic (depending on how much water is reduced).
On the contrary, by adding an excessive amount of water, we may end up making the drink not much different from regular mineral water, losing its benefits.

It always remains to point out that during the performance it is very useful Replacement of consumption of technical drinks a that of the water, Also taking into account what is ultimately consumed in the form of solid food or gel.

For more information on KEFORMA products: keforma.com
For more information on Dr. Bertuccioli: Sinalab

Who is theAlternatively, you can find other articles in the column about the integration implemented with KEFORMA.

How much do you drink while racing or training a bike?