What Is Energy Gel?

How often have you hit a wall mid run and wished you could give yourself a quick energy boost? 

Otherwise known as glycogen depletion, almost every runner or endurance athlete has found themselves in this situation at some point.  

But as our knowledge of sports nutrition improves, new products and trending snacks make running for longer distances more and more achievable.

One of the most popular ways to give your body a quick boost of fuel while on the go is a high quality energy gel.

1. But what are energy gels exactly?
2. Are they worth the money?
3. If so, how should you use them?

In this guide we’ll detail everything you need to know, so let’s jump right in:

What Are Energy Gels?

For runners, cyclists and other long-distance athletes looking for a boost, energy gels are your pocket-sized saviour—essentially, small packets packed with quick-digesting carbohydrates designed to give you a fast energy boost when you need it most. 

Whether you’re training for a 5K or an ultra, understanding what energy gels are and how to use them can make all the difference when it comes to smashing your goals.

Generally speaking, gels are super convenient, easy to carry, and formulated to get carbs into your system fast without weighing you down. 

Unlike a more traditional running snack like a cereal bar or a banana, they’re designed to be consumed on the move, providing a quick and easy to digest hit of energy to top up your glycogen stores. 

Being so easy to carry and formulated around giving a quick boost of energy, they can be a game-changer during long efforts when your body’s natural fuel reserves start running low. Many runners at all levels swear by energy gels, and have claimed that they’re key to getting them to the finish line in some of their most challenging events and training runs.

But how exactly do they work?

How Do Energy Gels Work?

Now would be a good time to dive into the science of energy gels - so feel free to skip this section if you know your stuff already.  

At their simplest level, energy gels work by delivering a concentrated dose of carbohydrates—usually maltodextrin, glucose, or fructose—that your body can quickly convert into energy. 

During longer runs that start to push your limits, your muscles rely on glycogen (essentially, stored carbs in your muscles) for fuel, but after about 60–90 minutes, those stores dwindle.  

Popping a gel replenishes those carbs, giving you the energy  needed to keep going. As they are simple carbs – consisting of one or two sugar molecules rather than longer molecule chains (complex carbs) - they get to work quickly. The energy gel gets broken down by the body easily and then rapidly absorbed into the blood stream. Many gels also include electrolytes like sodium and potassium to replace what you lose through sweat, plus some added caffeine for a mental and physical boost. 

There is even some evidence that energy gels help you psychologically get past the line too!

Types of Energy Gel

Traditional Energy Gels

Traditional ‘big brand’ running gels tend to be dense and thick, simply providing quick release carbs and consisting mainly of maltodextrin, fructose and various artificial additives. They require water afterwards to aid absorption. They are the most basic type of energy gel often bought bynewcomers to running.

Isotonic Gels

Isotonic gels add water and electrolytes to make them easier to drink without additional water. They are recommended when hydration is a major concern such as in very hot weather.

Budget Energy Gels

Budget energy gels are lower priced and lower quality. They tend to contain poor quality sources of carbohydrates such as maltodextrin. This means they pose a high risk of stomach upset..

Natural Energy Gels

Natural energy gels use natural ingredients and as few unnecessary ingredients as possible in order to provide energy in a more beneficial way and to aid digestion and prevent stomach upset.

The best example would be Maple Ignite natural energy gels which contain Grade A Canadian maple syrup for energy, pure sea salt for electrolytes - and nothing else.

Caffeine Gels

Caffeine gels are self explanatory - they simply contain caffeine in addition to their other ingredients - to help give an extra boost of energy and alertness. They are highly recommended during overnight races where sleep deprivation is a factor, but can be extremely helpful in regular runs too, giving you an extra boost exactly when you need it.

Our Maple Coffee energy gels contain just three ingredients, Grade A Canadian Maple Syrup for energy, pure sea salt for electrolytes, and pure coffee extract for a caffeine boost. The caffeine levels are carefully adjusted to prevent unwanted side effects, making them extremely popular with long-distance runners.

How to Use Energy Gels

While energy gels for cycling and running are extremely helpful, it is crucial to take them both in line with the manufacturer’s instructions, and in line with the latest sports nutrition science

1. Taking them too late will mean you’re already fatigued and losing pace - too late! You should start taking the gels from the start of the race and continue throughout. Some runners take one every 5KM, others take one every 20 or 30 minutes. What’s right for you will take some trial and error.
2. Taking too many may upset your stomach or make you feel a bit full for a while.
3. Taking the right amount at the exact right time will transform your race and give you a significant boost, every time. 

When to Use Energy Gels

Not everybody’s bodies are the same and your sex, weight, running experience and so on, all impact how many carbohydrates to take per hour. -  While following the best scientific advice and manufacturer’s instructions is the clear way forward at the beginning, you may have to tweak things a bit later going off your own experiences.

Most runners aim to take a gel every 20-30 minutes during long runs or races (or every 5KM if using distance as a guide), aiming for a minimum of 40–60 grams of carbs per hour, depending on your body and effort level. This guide varies of course, with elite runners able to comfortably take over 100g carbs per hour.

The trick is to take them before you feel wiped out, not when —think of it as topping off your tank before it’s empty to prevent yourself from getting to the point you feel especially fatigued.

Sip some water after a gel to help it go down smoothly. Not a sports drink, as too much sugar can upset your stomach. This isn’t needed with the highest quality gels, but it’s always helpful regardless.

Pro tip: practice your gel routine during training runs to nail the timing and see how your body reacts before race day.

We recommend keeping your gels in your run vest for easy access.

How to Avoid Stomach Upset

Stomach upset is a major issue for endurance athletes. In the best case scenario it means discomfort and potentially an unexpected run into the bushes. In the worst case scenario it means a DNF or even being unwell beyond the run itself.

While people vary and the best thing to do is to learn from your own experiences, a crucial tip is to avoid energy gels that contain artificial and unnecessary added ingredients. Good quality energy gels do not need many ingredients - a good source of carbs and a good source of electrolytes is more than enough, barring any additional ingredients like caffeine.

Energy gels with a long list of artificial ingredients are best avoided, especially if they are lower in price - this is likely to mean fillers, preservatives, artificial sweeteners, and other unhelpful, or even downright harmful ingredients that simply do not need to be there.

Advice from nutritionists & runners

Maple Ignite review by leading Sport and Exercise Nutrition Registered Nutritionist (SENr) BSc (HONS), PgDip.

"Just wow! I tried this gel (if you can call it that as it’s just two ingredients – maple syrup and sea salt) on a cold and wet trail run. As soon as the sweet, salty syrup hit my tongue it bounced off my taste buds. I was instantly energised and the weather felt like less of an issue.”

“Absolutely love these. Don't know how many I had, well into double figures, with no negative issues at all. Got me over the line at the Canalathon 100k in March. Ordered more for the upcoming Apocalypse 50 in May and Endure 24. Game changer for me, thank you.” Paul H, ultra runner

“Used the coffee maple and maple ignite for my longest run on Saturday! Was absolutely brilliant! The coffee towards the end was a great boost! Highly recommend - and easy on stomach! Not packed with fake stuff so a major plus!” Angelique club runner

“The only gels I use!! Simply perfect!. No stomach issues! Taste amazing and natural power!. What more would you need 🤷🏻♂️.” Paul, ultrarunner

Do Energy Gels Taste Good?

Good ones do! 

It’s not hard to make an energy gel taste good since the best ones use ingredients like maple syrup. 

That doesn’t mean you’ll love them all though, so find the best one for you and stick to it!

Which Energy Gels are the Best?

This is a subjective question that will depend on your own taste, needs and budget, but generally speaking you want to look for a gel that is:

1. Not full of unhelpful ingredients or cheap fillers
2. Not difficult to open without dropping or unpleasant to ingest during a long run
3. Contains the right level of carbohydrates for a running gel (At least  20g per gel
4. Easy to digest without causing stomach upset (especially important when looking for the best energy gels for ultramarathons and other longer distances)

While these are the undeniable things that make an energy gel worth buying, there are also subjective things to take into account, so it’s worth sampling any that seem good and then sticking to the one that gives you the best results.

Protein Rebel Maple Ignite Running Gels are the only energy gel in the UK that is made for runners, by runners, and their constantly growing popularity in the running world has reflected this. 

With only three easy to digest ingredients, eco-friendly packaging, and manufactured in small batches in the UK, most runners who try Protein Rebel’s energy gels stick to them in the long term.

Try them for yourself now and let us know what you think