Energy gels review

Sports gels

Sports gels consist primarily of sugars and water. As such they are a source of energy and also affect your hydration status. For instance a thick, syrupy gel can draw water from your body fluid into your intestines, causing you to dehydrate. An isotonic gel on the other hand, can hydrate you. Some gels provide other substances such as electrolytes, caffeine and even amino acids. There are sometimes additives as well, which are used to affect palatibility and extend shelf life.

Types of gel


These gels have the same osmolarity as the body fluids and therefore don’t cause water to move out of or into the digestive tract. This is useful, as water entering the digestive tract can dehydrate you, and increase your need to go for a toilet stop. These types of gels have a jelly like consistency. Examples include: SIS GO gels, SIS Smart 1 and High5 Isogels.


These gels have a texture more like syrup. They are stickier, and are best consumed with a few mouthfuls of water. This effectively makes them more isotonic and will help your body to maintain its state of hydration. Examples include:  Powerbar gels and High 5 gels.

What is in my gel?


Some gels provide a kick with the use of caffeine. Typical amounts per gel are 50mg. Caffeine is used to promote fat burning and reduce the perceived effort during endurance races. Guarana is also used for the same effects as caffeine.


Some manufacturers use sweeteners. Why they do this beats me, as gels are sickly sweet to start with, still they are present in products produced by SIS and CNP. Look out for the words sucralose, acesulfame K and aspartame if you want to avoid these.


Some manufacturers also use preservatives in order to extend the shelf life of their gels. While preservatives are not beneficial for health in a fresh product, they may make your supplies last longer. I know that many triathletes accumulate too many sports products, and end up having to throw them away. However, it is likely that many will last longer than is stated on the packets, as very sweet foods prevent bacteria from proliferating by robbing them of vital supplies of water. Examples of preservatives include: sorbitol, potassium sorbate and sodium benzoate.

Amino acids.

Some gels have aminos added to them. Amino acids are the building blocks of protein. The reason they are added is to aid in post race recovery. In theory they should prevent muscle tissue being broken down and used for energy. The GU Rocatane currently used in Iroman events in the US contains these. Look for the branched chain amino acids leucine, isoleucine and valine.


Some gels also contain thickeners. Examples include carrageenan and locust bean gum. These make a gel more gooey. Most of the typical thickeners used would normally be considered healthy. However, some may cause gastrointestinal distress for people with sensitive stomachs.

Ironman gels

The gels most often used in Ironman races are Powergels. Here is a list of Ironman events and the gels they offer:

•    South Africa: Powerbar gels; St George-Utah: Gu Energy and Gu Roctane Endurance
•    Australia: Powerbar gels; Lanzarote:  Powerbar gels
•    Regensburg: Powerbar gels; Nice: Powerbar gels
•    Austria: Powerbar gels; Frankfurt: Powerbar gels
•    Switzerland: Powerbar gels; UK: Powerbar gels
•    Sweden: Powerbar gels; Hawaii: Gu Energy and Gu Roctane Endurance
•    Florida: Gu Energy and Gu Roctane Endurance
We can see that with the exception of the US, where GU gels are used, Powerbar gels are completely dominant. All these gels are hypertonic so if you prefer isotonic gels you will have to make provision for yourself during the race.

Other commercial gels

•    SIS Go gels; SIS smart 1; High5 Energy gel
•    Maxim energy gel; Torq gel; Hammer gel
•    CNP pro energy gel    

When should I use a gel?

During an Ironman or 1/2 Ironman most people will use gels on the run. On the bike the danger of having a sticky mess on your hands and handlebars is a definite disadvantage. Many gels also require the availability of pure water, which may not be practicable on the bike if you are carrying sports drinks at the time. Most gels are not a significant source of sodium and other electrolytres, and so I would not advise that you try to rely on gels for all your energy requirements during a long distance race. Gels are also bad for the teeth as they stick to the teeth and gums even more than sports drinks. I would advise using them sparingly in training. Just have enough so that you know you can stomach them during race conditions.

During races?

Often you find that during a long distance race your cravings change as you go along. A whole day spent drinking sports drinks is no fun for most people. Having spent 5-7 hours on a bike consuming Powerbar drinks you will probably find you fancy something different. This is where gels may come in, however don't ignore other options such as drinking coke.

During training?

Over reliance on sugary foods during training is not ideal for building up your ability to become a lean, mean fat burning machine. For long steady efforts below race intensity I do not advise the habitual use of gels. When training on the bike, especially at below race intensity, why not eat natural foods such as ham and cheese rolls, flapjacks and dried fruit. Use gels when you up the intensity. This is where they come into their own as they are quicker to digest and absorb than rolls and flapjacks. When running you do not need gels unless you are going over the hour, or running after a long bike ride. Again the main time to use them is when training at race intensity. Learn how to handle a gel sachet (or gel flask) wsee below.

How often?

The general rule is one 45g gel every 20 minutes washed down with 200mg of water. You may need to vary this depending on the conditions. With isotonic gels you may not need the water at all.

Gel flasks:

Why use them?

When performing in long distance events, the number of gels sachets required to complete a 5 hour marathon could reach 15. This number of gels can be a challenge to open, irresponsible to discard, sticky for your hands or even difficult to find in your nutrition store. A neat solution is the gel flask. The gel flask is both less messy, better for the environment, easier to access and crucially allows you to change the gel concentration.

Gel concentration?

Make a hypertonic gel isotonic by watering the contents of a standard gel down. Typically adding the same volume of water as is in your gel, should give you something approaching an isotonic gel. Whether you choose to do this is your choice. Hypertonic gels are normally best taken with plain water to wash them down. Isotonic gels can be had on their own, and so can be consumed in between aid stations. You may also find that you prefer the taste of hypertonic over isotonic gels or vice versa. It really depends what gets on best with your taste buds and your stomach.

Where can I get one?

If you wish to see your options, go to the Amazon website, type in “gel flask”, and inspect the range that is available. Typically they will cost between £5 and £10 or $6-$12 (2012 prices). Gel flasks range in size from 5-8ox (roughly 150-250ml). This is 3-5 times more volume than is contained in a typical gel sachet.

Ingredients of some popular gels:

  • Powerbar gels (41g) – 110kcal, carbs 27g, (sugars 10g). Na 200mg, K 20mg. Has 37% carbs as sugars. Latte and tangerine flavours have 50mg of caffeine and ginseng and kola nut. Most other flavours have 25mg caffeine and ginseng and kola nut. Vanilla, raspberry, caramel and plain have none.
  • Powerbar ride shots (7g) – 20kcal, carbs 5g (sugars 4g), fibre 0.2g, Na 3mg. As sugar, glucose, water, gelatine, invert sugar, citric acid, glycerol, sorbitol, sodium citrate, carrageenan, locust bean gum, barley, veg fat, carnauba wax, liquorice, caffeine 50mg? (if so could lead to high caffeine doses) all data approx.
  • SIS Go gels (60g) – 86kcal, carbs-22g (sugars trace), has acesulfame K. ISOTONIC.
  • SIS Smart 1 gel (60g) – 86kcal, carbs-22g (sugars trace), has acesulfame K, sucralose, bioflavanoids and caffeine 50mg (= cup of coffee) - ISOTONIC.
  • High 5 energy gel (38g) – 92kcal, carb 23g, (sugars (glucose2/fructose1) 7g), Na 35mg. Also has caffeine 35mg, choline 35mg and taurine. Has 30% carbs as sugars.
  • Maxim energy gel (100g) – 300kcal, carb 74g, (sugars (glucose/fructose). May be mostly sugars. Na 35mg. Vitamins B, C and E at c.45% rda.
  • Clif Shot Bloks (30g) – 3 pieces = 30g. 100kcal, carb 24g,  (sugars 12g), Na 70mg, K 20mg, Fe 2%rda. Mostly made from rice syrup.
  • Torq gel (45g) – 114kcal, carbs 29g (sugars 10g), Na 50mg, Ch 86mg, K 11mg, Mg 1mg Ca 4.5mg. Maltodextrin:fructose 2:1. Forest fruits flavour has guarana (=89mg caffeine).
  • Carb Boom (41g) – 110kcal, carbs 26g (sugars 4g fructose), Na 50mg, K 75mg, Caffeine 50mg, Cocoa, Coffee, Citric Acid, Phosphoric Acid, Potassium Sorbate and Sodium Benzoate
  • Gu gels (32g) – 100kcal, carbs 25g (sugars 5g fructose), Na 50mg, K 40mg, Caffeine, amino acids – BCAA + histidine. Potassium Sorbate and Sodium Benzoate
  • GU Roctane Ultra Endurance (100g): - typically 32g gel. Carbs 78g of which sugar 15.5g, Protein in form of aminos 3.8g, a-keto glutarate 1.5g, Na 390mg, K 172mg, caffeine 110mg. Ingredients: Maltodextrin (Glucose Polymers), Filtered Water, Fructose, Roctane Amino Blend (Histidine, Leucine, Valine, Isoleucine), Ornithine Alpha-Ketoglutarate (Okg), Sodium Citrate, Malic Acid, Citric Acid, Potassium Citrate, Natural Pomegranate Flavour, Natural Berry Flavour, Calcium Carbonate, Sea Salt, Caffeine , Contains preservatives [Sodium Benzoate, Potassium Sorbate], Natural Vitamin E. Gluten-free. Dairy-free. 35mg of caffeine
  • CNP pro energy max (45g) – 101kcal, carbs 25g (maltodextrin), l-caffeine, guarana, glucoronolactone, n-acetyl tyrosine, phenylalanine, taurine, potassium chloride, magnesium chloride, B3, B6, B12, sucralose.
  • Hammer gel (33g) Syrupy like a powergel. 90kcal, Carbs 22g, Na 25mg, K 20mg, leucine 6mg, alanine 3mg, valine 3mg, isoleucine 1.6g. Ingredients: Maltodextrin, Filtered Water, Apple Juice Concentrate, Energy Smart® (Fruit Juice, Natural Grain Dextrins), Ground Cinnamon, Malic Acid, Vanilla Extract, Potassium Sorbate (as a preservative), Salt, Amino Acids (L-Leucine, L-Alanine, L-Valine, L-Isoleucine), Potassium Chloride.