Energy gels: what you need to know

A definitive guide to energy gels that explains everything you need to know about the power in the packet

What's in an energy gel?

Energy gels have been a common feature in the training regimes of triathletes since they first hit the market back in the mid 1980s. A cross between an energy bar and a sports drink, delivered in a tiny, easy-to-carry sachet, these concentrated ‘sugar hits’ deliver an easy, instant energy boost during long bouts of exercise, helping to replace depleted carbohydrate stores. 


Not only has their popularity grown, energy gels have also become more and more sophisticated. The first gels (Squeezy) were a simple sugar and salt mix, whereas nowadays the wide range of gels available gives the consumer the choice of added caffeine, extra B vitamins, a spectrum of electrolytes, antioxidants and even fats in
the form of MCT’s (medium chain triglycerides). No wonder people are bewildered by the choice of gels.

Most energy gels on today’s sports nutrition market provide between 100-110 calories and 23-28g of carbohydrates, and those with added caffeine provide 20mg-50mg of caffeine. Caffeine taken before exercise can lead to enhanced performance and may provide a mental burst of energy. But the effect on performance of caffeine taken during exercise (especially in such small dosages) is yet to be conclusively proven. It’s also worth bearing in mind that individual responses to caffeine vary widely. 

Are energy gels with caffeine worth it?

What’s in an energy gel?

Which energy gels to buy?

Energy gels cost around £1 per ‘hit’. Using gels on a daily basis could therefore prove to be quite an expensive habit. With that in mind, use them wisely and in moderation, and/or buy in bulk. Leading brands are available in boxes of 20-30 gels, which reduces the cost by 10-15% in most cases. Alternatively, you could experiment with a few natural ingredients at home. Ironman triathlete Brendan Brazier has some recipes in his book The Thrive Diet, and recommends blending dates, agave syrup, a touch of sea salt, and lemon or lime juice. The resulting ‘gels’ can be transported in small freezer bags or zip-lock bags. 

Honey is one of the most useful home ingredients, and is by far the most natural and unprocessed of all sugars. It contains a spectrum of vitamins, minerals and amino acids, which is perfect fuel during exercise when you need a quick and complete energy boost. You can also dilute honey if you find it too sweet or viscous. 

Gel taste and palatability is a vital consideration when buying and using any gels, so find one that you actually like and can digest easily. Another consideration is to find a gel that opens easily – you don’t want to be fumbling around during a race. Choosing one with an easy tear-lid is the best bet for a swift hit. 

How to take energy gels

Most gels on the market must be taken with around 200-300ml of plain water (not carbohydrate drinks), unless you choose an isotonic gel, which can be taken on its own. Science In Sport, a leading brand in sports nutrition, introduced the world’s first isotonic gel, the Go-Gel, which is now hugely popular with athletes of all standards. Isotonic simply means ‘of equal concentration’ and, in this case, describes the gel concentration as being in balance with the body’s fluids – so you don’t need to dilute it with water. 

Over-consumption of concentrated energy gels can cause dehydration, as water is drawn from the body and into the gut to facilitate absorption. It’s therefore of utmost importance to avoid over-consuming gels or taking them alongside energy drinks. 

Gels are by their very nature concentrated sources of sugars, so remember to take care of your teeth! Wash down the gels with water, and again, avoid over-consumption or snacking on energy gels. Sugar consumption is one of the leading causes of gum disease and even the great sport of triathlon isn’t worth that

Energy gels versus energy bars

Energy gel essentials

Try out a few for taste, palatability and how well you digest them. Basically, experiment and find one that suits you.

Make use of free samples if available.

The 25-30g gels are suitable to take every 30mins during exercise with 200-300ml of water (unless isotonic gels are used). Ensure the recommended intake of 60-80g carbs per hour is not exceeded (regardless of body weight).

 Avoid taking gels with carb drinks. This combination is likely to cause gut distress such as bloating, cramping or nausea.

Avoid over-fuelling with gels, and try them out in training before using them during races.


If you use gels on a near-daily basis, look for those that are free of artificial sweeteners such as Aspartame and Acesulfame K.

Guide to using energy gels

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