This article explores energy gels, how they turn energy into performance, and the ingredients behind their effectiveness.
Whether training for a marathon or seeking a boost for cycling sessions, discover how these gels can optimise energy and performance.
What Does an Energy Gel Do?
As the name suggests, an energy gel provides energy quickly. Before choosing one, however, understand briefly how it works and what happens inside the body.
Energy gels are concentrated carbohydrate sources that, after gastrointestinal digestion and absorption, raise blood glucose levels. To get glucose into muscle cells, the body stimulates the pancreas to release the hormone facilitating entry: insulin.
During exercise, we want energy as quickly as possible. The body’s preferred metabolic pathway is glycolysis, the reaction that breaks down glucose and converts it into ATP, the familiar energy currency providing that boost. This consequently helps:
- Increase sports performance by fuelling muscles.
- Prevent fatigue and depletion of muscle and liver glycogen stores.
- Improve concentration and mental endurance.
- Prevent or delay muscle catabolism (muscle mass loss).
What Does an Energy Gel Contain?
Each gel is different, making it difficult to choose the most efficient, suitable option. Therefore, understanding composition makes choosing much easier.
Carbohydrates
Every energy gel’s basic fuel is simple, rapidly absorbed carbohydrates, also called sugars. It is important to combine at least two carbohydrate types because transporters may become saturated in the intestine (combining types improves intestinal absorption). This appears on the label: look at the ratios.
In the intestine, each carbohydrate uses a type of transporter to move into the bloodstream. Different carbohydrates use more absorption pathways, helping avoid saturation. At the same time, maintain adequate hydration, facilitating absorption of the carbohydrates consumed and preventing sugars from dehydrating us.
Electrolyte Salts
Many gels include minerals to replace electrolytes lost through sweating and kidney filtration. These are particularly useful in hot climates, endurance sports, or activities where sweating is high and water contains insufficient minerals to offset losses. Salt composition also matters for the sport and its duration, particularly the specific sodium content, discussed in more detail below.
BCAAs
Some labels also include BCAAs, and although this sounds complicated, it simply means three branched-chain amino acids: leucine, isoleucine and valine. These help reduce central fatigue and muscle damage from exercise. Unless your sport lasts a very long time, such as eight hours or more, including them during training is less effective.
They are somewhat more complex molecules , harder to digest than carbohydrates. They do not provide quick energy, making them more useful for recovery. They can also become saturated: more is not always better. Assess the dose, remembering that protein foods generally also contain amino acids.
Caffeine
Stimulants, particularly caffeine, are increasingly added to gels. Caffeine is associated with greater alertness because it blocks adenosine receptors. Adenosine has sedating, relaxing effects; preventing receptor binding stops those effects.
Caffeine also has other advantages, acting as an analgesic to reduce perceived pain. Its thermogenic properties also activate fat use as fuel for exercise.
These features are particularly useful in very long events. Depending on dose, tolerance and circumstances, with caution in hypertension, caffeine may be useful. Like BCAAs, however, it is not essential in a gel.
For shorter events without multiple fuelling stops, caffeine can be taken shortly before exercise rather than in the gel, allowing time to react if intestinal motility increases.
Antioxidants and Vitamins
Exercise increases energy demands and metabolism, raising free radical production and attracting the supplement industry’s attention.
Recently, it has become increasingly popular to use antioxidants such as vitamins E and C to counter oxidative stress arising during high-intensity exercise. This sounds promising, as free radicals can damage cells and tissues, but it may be less useful than it seems. Otherwise, exercise itself might seem harmful, which it is not.
What actually happens is that physical activity stimulates endogenous antioxidant defences within our own body. Free radicals act as signalling molecules, indicating physical stress, and the body responds by adapting and increasing protection against this stress. Current evidence suggests antioxidant supplementation can interfere with these adaptations. Antioxidants during exercise may block anabolic signalling pathways , impairing the body’s natural training adaptations. They can therefore be counterproductive.
Non-antioxidant vitamins, such as B vitamins, are different. Exercise generally increases vitamin B2 and B6 requirements because they optimise nutrient use for energy during activity. B2 helps form FMN and FAD, energy-related molecules, while B6 helps release glucose from glycogen. They may therefore be useful additions to gels.
When Is an Energy Gel Recommended?
This depends on the sport, although, spoiler alert, with prolonged, high-intensity exercise, we may well recommend one.
Broadly, short exercise generally needs no gel, even when intense: stored glycogen is sufficient. Gels become more useful beyond an hour, especially during exhausting endurance exercise.
Taking a gel approximately 15 or 30 minutes before exercise raises blood glucose for a quick initial energy source, although this is not needed in every discipline. Once active, schedule fuelling intakes during exercise. Ideally, consume a gel every 45 minutes to 1 hour to maintain blood glucose and continuous energy. Never forget hydration. Without water, gels could cause dehydration and put you out of action.
Individual tolerance also matters. Some brands or gel formulations may suit you better than others for performance and gastrointestinal comfort.
Are There People Who Cannot Consume Energy Gels?
As with everything, differences between individuals determine suitability. Intolerances, allergies, sensitivities and gastrointestinal problems are crucial when choosing.
Some gels contain gluten, dairy or fructose, potentially triggering common allergies and intolerances . Reading labels carefully can prevent buying something that causes problems. With diabetes or related conditions , carbohydrate quantities must be considered when adjusting insulin and managing blood glucose.
Inadequate hydration alongside gels may cause gastrointestinal problems. If they also contain stimulants such as caffeine, the effect can be explosive.
What Can You Use in These Cases?
Fortunately, alternatives exist within gels or in other product ranges. Some exclude allergens, while others address lactose or fructose intolerance by omitting those sugars.
For people prone to digestive problems, sports drinks may be preferable. Being already diluted, they provide hydration alongside nutrients, facilitating intake and absorption.
Once products fit your preferences or medical needs, test them through trial and error during training and, above all, never try new products on competition day.
An Energy Gel Strategy for Racing
To introduce gels into your sport, develop a strategy to get the most from them. First ask: How Much Energy Will I Need During the Race?
Use some maths to estimate the calories used during training. This depends on basal metabolic rate (BMR) and total energy expenditure (TEE), including exercise duration and intensity.
After calculating race calorie requirements, you can replace all or only part of them. Each carbohydrate gram provides 4 kcal. Divide estimated activity expenditure by this value to obtain carbohydrate grams. As a reference, the common range is 30g to 60g of carbohydrates per hour.
How should this total be divided? Fuelling according to race duration is key. Take a serving approximately every 30 minutes to 1 hour, remembering hydration from the outset. Drink water in small sips, ensuring approximately 400 to 800ml per hour of effort. This depends on sweating, weather and scheduled sugar intake. It is important to avoid mixing gels with isotonic drinks containing extra sugars that could raise the total too far and cause problems.
When Should You Take a Caffeinated Gel?
Caffeine or no caffeine? This is an area where we often hesitate when choosing, knowing it can be a powerful performance ally, but misuse can make it an enemy.
The best way to enjoy its reduction of perceived effort and muscle fatigue is to consume it occasionally and at the right dose. Excess may upset the stomach and increase dehydration risk, so alternate non-caffeinated and caffeinated gels. During a long run or marathon, no more than two caffeinated gels are advised, spaced apart between fuelling stops.
In a race involving 5 gel servings, for example, two could contain caffeine. Ultimately, the dose makes the poison, and individual differences matter. It is advisable not to exceed 200mg total caffeine generally, although tolerance, age, sex, weight and sport can change that figure.
How Long Does an Energy Gel’s Effect Last?
Gels are rapidly absorbed to raise blood glucose and provide quick energy. They reach the bloodstream readily, but their effect also tends to disappear quickly.
The blood-glucose-raising effect can depend on carbohydrate composition and quantity , but generally lasts around 30 minutes. Regardless of averages, testing during training is the best way to determine a specific gel’s effect. Try different brands and types to understand your response.
How to Choose a Good Energy Gel
Before buying the gel you have been considering, first choose a carbohydrate quantity and ratio that suits you. More is not always better. Intake should meet needs and depends less on weight than on your stomach and its ability to assimilate and digest carbohydrates.
During sport, most blood is in the muscles, making digestion harder. Generally, 30g to 60g of carbohydrates per exercise hour are well tolerated, but the gut can be trained to assimilate up to 90g without causing gastrointestinal problems.
Next, maintain electrolyte balance to compensate for sweat losses. Sodium is the first mineral to check: without it, cells cannot transmit electrical signals properly or regulate cellular water. At least 100mg can be useful, with more if sweating is high.
Other ingredients matter less than getting these two components right. If caffeine suits you and helps, choose some gels with it and some without. Beyond ingredients, texture, flavour and packet size may decide whether a gel works for you. Preferences and convenience support consistent use and enjoyment of the race.
Top 5 Energy Gels
Your ideal gels must suit your needs. Among the huge range available, these are some favourites worth checking against your requirements:
- Santa Madre
- Crown Nutrition
- Maurten 100
- High Fructose 226ERS
- Power Gel Hydro
- Fanté
- Ciclo Energy Life Pro (fructose-free)
- Science In Sport (fructose-free)
