What Is an Energy Gel?
Reading time: 10 min

What Is an Energy Gel?

Reading time: 10 min
Learn why the energy gel is the most useful supplement for endurance athletes.
What Is an Energy Gel?

The energy gel is a staple supplement among endurance athletes, but there are still many questions and doubts surrounding it.

Why use an energy gel? What does it contain? How does it taste? Is it harmful? Why should I use it?

Let's answer these questions.

Why use an energy gel? 

Your body needs energy to function. This energy comes from carbohydrates. The body also has its own stores of carbohydrates, stored as glycogen in your muscles and liver.

During intense endurance exercise, you need lots of energy. Since your body exhausts its glycogen stores within little more than two hours of exercise, you need to supplement carbohydrates to preserve glycogen stores as long as possible.


Because once your body runs out of glycogen, it will stop functioning and you will "hit the wall". In other words, you will run out of energy and will be forced to quit your exercise.

At that point, an external source of carbohydrates won't help you. You need to consume carbs before your body exhausts its glycogen stores.

Consumption of glycogen storesEat while you can. Once fatigue kicks in, it's too late.

You should know that ingesting carbs during exercise will only slow down glycogen consumption and not prevent it. Often you may hear claims that a supplement fills your glycogen stores during exercise, but that's not how it works.

There is another important reason to use energy gels. It's slightly ironic, but as your need for energy increases, your body's ability to digest food decreases. In other words, when you need energy the most, it becomes the hardest to obtain it.


Because in that moment your body goes into "battery saving" mode and shuts down all less important functions in the body, which includes digestion.

That's why during intense exercise you need to ingest simple sugars, which are the easiest for your body to digest, absorb, and turn into energy.

During intense exercise, your body needs energy in the form of carbohydrates. The energy gel is the most practical and efficient way to provide that energy to your body.

What's in an energy gel?

The basic ingredient of all energy gels is carbohydrates (sugar). This is where the name "energy" comes from. If it doesn't have carbs, it's not an energy gel.

Most energy gels also contain minerals in one combination or another. It may be salt, the most important mineral to supplement during exercise, or a more complex combination of minerals that completely replaces the electrolytes you lose during exercise.

Some energy gels also contain vitamins, but that has no functional value during intense exercise.

The basic ingredient of the energy gel is carbohydrates.

Carbohydrates in the energy gel

During exercise you need fast-acting carbs. That's carbs that can quickly be absorbed and turned into energy.

But that doesn't necessarily mean that they need a high glycemic index. Fructose, for example, has a very high absorption rate but not a high glycemic index.

The most common carbohydrate in energy gels is glucose. This simple sugar is the primary source of energy in your body.

Research shows that the optimal absorption of carbohydrates requires a combination of glucose and fructose.

The reason is that these two simple sugars use different carbohydrate transporters in your body.

If you intake only glucose, your body will only be able to absorb 60 grams of carbs per hour. By adding fructose, the absorption can increase to 90 grams per hour.

The optimal source of carbohydrates in your energy gel is a combination of glucose and fructose in the 1:0.8 ratio. 

Is sugar harmful?

One of the main reasons that so many athletes have issues with proper nutrition during intense exercise is the fear of consuming sugar.

This is the consequence of the erroneous idea that afflicts many top-level athletes that sugar is harmful and causes an increase of body mass.

This myth, obviously, does have its logic. Sugar is rich in calories, so it can definitely lead to an increase of body mass. It can also be harmful, as foods with a high glycemic index cause an insulin reaction, which can lead to diabetes. But this will not happen during exercise.

It's important to be aware of the difference between someone who consumes excessive amounts of sugar while the body is inactive and does not need this energy (in this case, sugar can definitely be harmful) and an endurance athlete whose body during intense exercise is fully active and needs energy to function

A lack of energy during intense exercise leads to several health issues, such as a decline of the immune system, ailments, and injuries. As an endurance athlete, you must realize that sugar is your friend.

Sugar is harmful when your body doesn't need the energy, but lack of sugar is equally harmful when during intense exercise energy is very much needed.

Glucose or maltodextrin?

Some energy gels contain glucose, others contain maltodextrin. What's the difference?

Maltodextrin is a chain of glucose molecules. Unlike glucose, maltodextrin is not sweet because the acids in your mouth are not able to break it down into glucose molecules, which is why you don't feel its sweetness.

This is important because the optimal combination of carbs in your energy gel contains glucose and fructose. Since fructose is naturally very sweet, maltodextrin prevents the gel from being too sweet.

Best source of energy during exerciseNrgy Unit Gel contains maltodextrin and fructose in the optimal ratio of 1:0.8.

There's another difference between maltodextrin and glucose, but this one can get a little complicated. In simple terms, because maltodextrin molecules are composed of several glucose molecules, they are larger and thus have a smaller concentration (osmolarity/osmolality). This can potentially positively influence gastrointestinal comfort, but further research is needed.

Maltodextrin are glucose molecules with a less sweet taste and possibly better absorption than glucose. 

Minerals and hydration

Energy gels also contain minerals. When minerals interact with a fluid, for instance blood, they acquire an electric charge and become electrolytes. When we talk about minerals or electrolytes, we are basically talking about the same thing.

Electrolytes are essential for the functioning of pretty much all your body functions, which is why you must preserve their balance.

When we talk about hydration, we refer to the combination of the intake of fluid and electrolytes. Because of the latter, drinking only water, especially over several hours of intense exercise, may be problematic and lead to health issues, such as hyponatremia.

For an endurance athlete, hydration is essential. That's because during intense exercise you lose both fluid and electrolytes with your sweat.

This is where the importance of the electrolyte balance comes into play. The thing is, you lose high amounts of salt (sodium chloride) in your sweat but not many other minerals, such as magnesium. It's best if the concentration of minerals in your energy gel reflects that.

Also keep in mind that an energy gel can take care of one part of the hydration equation, that is a correct intake of minerals. You must still drink fluid, which is why during intense exercise you need to combine energy gels with a sports drink or water.

An energy gel contains minerals, which represent one part of the hydration equation. The other one is a sufficient intake of fluid in the form of a sports drink or water.

Energy gel and magnesium

Magnesium is one of the ingredients that has long been problematic both in energy gels and other sports supplements. There is myth that magnesium prevents muscle cramps, which is why many manufacturers go heavy on this mineral and market it as their product's benefit.

Magnesium does not prevent muscle cramps. A sufficient intake of carbohydrates does.

Magnesium is an extremely important mineral for your body, but you lose very little of it with sweat. That's why it makes no sense to supplement it in great amounts. It can also have a laxative effect and lead to digestive issues.

A high amount of magnesium can lead to digestive issues. 

How to correctly use an energy gel?

First you must realize that all dietary supplements are simply food in another form. We often hear this distinction between "real" food and supplements, but as far as science is concerned, both contain nutrients in certain combinations and ratios.

An energy gel is basically a concentrated dose of sugar, which your body can use as a source of quick energy.

The recommended intake of carbohydrates during exercise depends on the length and intensity of your exercise. High-level endurance athletes intake between 90 and 120 grams of carbs per hour, but this is a very high intake that requires the correct combination and ratio of carbs in your supplement and a sufficient preparation of your gut to absorb such high amounts. Also keep in mind that it is not confirmed that intakes of above 90 grams per hour actually result in increased absorption.

The energy gel is optimized for a high intake of carbohydrates during exercise both in terms of practicality (small volume considering the amount of energy) and optimization of ingredients, which obviously differ from gel to gel.

Taking all this into consideration, you should consume between 1 to 4 energy gels per hour (depends on exercise intensity and the amounts of carbs in your gel).

Energy gel source of sugarYou should consume between 1 to 4 energy gels per hour of exercise.

There's another question that gets asked a lot. Can I use an energy gel before or after exercise?

Since it doesn't contain protein, an energy gel is not optimal after exercise, but you could still use it to replenish your glycogen stores.

On the other hand, it makes sense to use an energy gel before exercise. If you ever saw an athlete squeezing a gel before the race even started, it's to provide the body with an external source of energy to immediately slow down consumption of his or her body's glycogen stores.

On a less serious note, we definitely don't recommend to indulge in energy gels in the evening in front of the TV, no matter how delicious they may be.

The correct use of the energy gel is to slow down glycogen consumption during intense exercise. The number of gels you need depends on exercise length and intensity and your gel's carbohydrate content.

What does the energy gel taste like?

Many athletes worry that an energy gel has an unpleasant or irritating taste and causes thirst or digestive issues.

Unfortunately, there is no universal answer regarding the taste and consequences of consuming an energy gel. It all depends on the athlete and the specific energy gel.

If we look at a high-quality energy gel, such as Nrgy Unit Gel or 4Energy Gel, which are based on natural ingredients and carefully crafted formulations, these are undoubtedly very tasty dietary supplements that with correct use shouldn't cause unpleasant sensations or digestive issues.

However, we can't promise you the taste or effect will be to your liking. What we can do is advise you to try these gels yourself in accordance with our recommendations and instructions.

The energy gel can be a very tasty dietary supplement, but the taste is obviously subjective, so it's best if you try different gels and see which ones you like. 

Is an energy gel harmful? 

Based on the prejudices one might have against dietary supplements and/or sugar, you might perceive the energy gel as potentially harmful.

If an energy gel doesn't contain harmful or artificial additives and sweeteners or an inadequate mineral ratio, e.g. too much magnesium, with correct use from science's standpoint there is no reason an energy gel should harm you.

As said, during intense exercise your body needs energy. This energy comes from its own glycogen stores and from an external supply of carbohydrates, primarily sugars. The energy gel is one of the most efficient sources of energy that allows you to preserve your glycogen stores as long as possible.

Of course, you must take into account your digestive system's preparation level to ingest a high amount of carbohydrates. Without training your gut, we definitely don't recommend you try the intake of professional athletes, as this will very likely lead to digestive issues.

An energy gel could also be harmful if you use it when your body doesn't need the energy. It is a dietary supplement, intended to supply energy during intense exercise. It is definitely not meant to be enjoyed as a dessert or a vice.

If used correctly, the energy gel won't harm you. 

Which energy gel do we recommend?

There is a plethora of energy gels on the market. Their effectiveness and suitability depend on several factors.

The most important thing is that they contain the correct combination and ratio of carbohydrates (glucose and fructose) and a correct ratio of minerals, which are key for optimal hydration.

If you are a high-level endurance athlete, our top pick is Nduranz's Nrgy Unit Gel. This gel contains 45 grams of carbohydrates per gel, which is double than most available gels. It also contains the optimal ratio of carbohydrates (1:0.8 maltodextrin to fructose ratio) and a mineral mix that replaces only the electrolytes you actually lose in your sweat.

Best energy gel for elite athletesThe best energy gel for elite athletes who require an extremely high carbohydrate intake.

A very popular energy gel is our own 4Energy Gel. This gel is distinguished by its incredibly refreshing taste, derived from freshly-squeezed fruit juice. This energy gel is perfect for athletes who don't need the highest carbohydrate intake, but still require a fast-acting and reliable source of energy during exercise.

For the most intense exercise, we recommend Nrgy Unit Gel, and for less intense exercise our pick is 4Energy Gel.


The energy gel is the most practical source of energy for endurance athletes during intense exercise.

The basic ingredient of an energy gel is carbohydrates. The optimal source is a combination of glucose (maltodextrin) and fructose in a 1:0.8 ratio.

Energy gels also contain minerals, which are required for optimal hydration. It's best to avoid gels that contain high amounts of magnesium, as it may cause digestive issues.

The correct use of the energy gel depends on the length and intensity of your exercise. It is important that you train your gut before attempting a high carbohydrate intake of 90 grams or more per hour.

For the most intense exercise, we recommend Nrgy Unit Gel with 45 grams of carbohydrates per gel.

For less intense exercise, we recommend 4Energy Gel with a uniquely refreshing taste that doesn't require water.

If you are an endurance athlete and are still not familiar with the energy gel, we definitely recommend you try out this incredibly practical, efficient, and tasty dietary supplement.