Disclaimer: This article is not intended to be a scientific comparison between energy gels. It is compilation of nutrition facts about most of the energy gels commonly available in the UK and France, complemented by a subjective comment on their taste and texture. Please feel free to comment on it.
  • Update 18/10/2008: corrected Honey Stinger weight, added Hammer.
  • Update 14/12/2009: added Over Blast, Overstim.s and mX3.
  • Update 12/01/2010: added Carboshotz.
  • Update 12/04/2010: added Isostar Gel Energy and Multi Carbo Gel.
  • Update 23/06/2010: added GU Energy Gel.
I've tried to buy most of the gels I could find in shops or online. The most common in UK shops are PowerGel, High5 and SiS GO, but when you look carefully around, there are quite a few of them: I've ended up with nearly 3kg of running treats! The idea was to taste them for real and not only to report their composition in a table.
However, there are a couple of other gels I haven't tested: EAS energy gel (looks more designed for body builders), Cyto gel (sold only by 24 pack), Clif Shot Energy Gel (can't find a UK retailer), Fireball, Cytomax Gulp'n Gel. Also, I didn't try the full range from High 5, assuming they must be fairly similar. High 5 IsoGel Plus has extra caffeine (35mg) and High 5 IsoGel X'treme is designed to "boost energy, focus and agression", although the official website is very evasive on the actual content.

I am continuously updating this page when I can get hold of more products.

gels

Weight

Most gels provide about 100KCal in 40g. Some are provided in bigger resealable pouches intended for several usages to pack up to 300KCal. The gels with the most important level of sugar will contain less water and therefore have a higher energy-to-weight (E/W) ratio. Pure sugar Honey Stinger reach an amazing 3.24 KCal/g, whether largely water-diluted maltodextrin-based SiS GO gels only pack 1.3 KCal/g!

Table 1: energy and weight

Gel Weight Energy E / W

(g) (Kcal) (Kcal/g)




SiS GO Gel 67 87 1.3
SiS Smart1 Gel 67 88 1.31




High5 IsoGel 38 92 2.42
High5 EnergyGel (Plus) 38 92 2.42
Torq 45 114 2.53
Carboshotz 45 117 2.6
Squeezy Gel 25 65 2.6
PowerGel 41 109 2.66
Carb BOOM Gel 41 110 2.68
Multipower – Multi Carbo Gel 40 107 2.68
GU 32 100 3.13




Isostar Actifood 90 187 2.08
Lucozade Carbo Gel 45 123 2.73
mX3 extreme 25 74 2.96
Scientec Nutrition Over Blast 25 74 2.96
Overstim.s (Energix / Antioxidant) 27 80 2.96
Aptonia Energy Gel 70 208 2.97
Maxim Gel 100 300 3
Overstim.s (Coup de fouet / Red Tonic) 25 81 3.24
Isostar Gel Energy 35 114 3.26
Honey Stinger Gel 32 120 3.75


Carboyhdrate type

They are basically 3 kinds of gels available, hence the 3 groups in the comparison tables. The ones mostly based on maltodextrin (a carbohydrate that isn't sweet, derived from partial hydrolyse of starch), the ones based on glucose syrup (which are extremely sweet) and the ones combining maltodextrin and glucose/fructose. Some researchers suggest that a ratio 2:1 maltodextrin:fructose/glucose (ie. 33% sugar) is optimal. However, most of those are linked somehow to a brand, so it's tricky to get a fair opinion.

Isotonic

Isotonic gels can be consumed without extra water. This can be an advantage, but for most people water is usually needed anyway during a race anyway! I think it's becoming increasingly trendy to say that sport food is isotonic, and I expect most gels to be isotonic in a couple of years.

Caffeine

Some gels include 25 to 90mg of caffeine. As for comparison, the caffeine amount in coffee varies between 40mg (regular espresso) and 300mg (Star***** biggest brew). It's always been controversial whether caffeine is beneficial to long distance running. On one hand it's a psychological and metabolism booster, on the other hand it's a diuretic, it increases the blood pressure and might lead to digestive problems.

Table 2: composition

Gel Carbohydrates Sugar Isotonic Caffeine


(% carb.)






SiS GO Gel maltodextrin 0 YES
SiS Smart1 Gel maltodextrin 0 YES 50





High5 IsoGel maltodextrin, glucose 30 YES
High5 EnergyGel (Plus) maltodextrin, glucose, (fructose) 30 or 46
(30)
Torq maltodextrin, fructose 33
(89)
Carboshotz Corn syrup solids 19
(80)
Squeezy Gel maltodextrin, fructose ?

PowerGel maltodextrin, fructose 38
(25, 50)
Carb BOOM Gel maltodextrin, fructose 11
(50)
Multipower – Multi Carbo Gel maltodextrin, fructose, dextrose 36
5
GU maltodextrin, fructose 20






Isostar Actifood glucose syrup ?

Lucozade Carbo Gel glucose syrup 15

mX3 extreme glucose syrup, fructose 68

Scientec Nutrition Over Blast glucose, (maltodextrin) ?
30
Overstim.s (Energix / Antioxidant) glucose syrup, (maltodextrin) 35 or 45

Aptonia Energy Gel glucose syrup, (maltodextrin 5%) 58

Maxim Gel glucose syrup 69

Overstim.s (Coup de fouet / Red Tonic) glucose syrup 76

Isostar Gel Energy glucose syrup 62

Honey Stinger Gel honey (pure sugar) 100
(32)
* caffeine weight in brackets means that only some of the flavours do contain caffeine.

Cost

Price are hard to compare. If buy bulk you'll obviously pay less. I originally wanted to buy them all by the unit to compare their prices that way. As some gels are only sold in bulk, I eventually had to mix things up a bit. There is a wide range of prices, but on the whole, they are generally fairly expensive for a mix of water, sugar and minerals. Many websites propose recipes to make your own gels for a fraction of the price.

Table 3: cost

Gel Price By E / P

(£)
(Kcal/£)




SiS GO Gel 0.9 10 96.67
SiS Smart1 Gel 1.6 1 55




High5 IsoGel 1 2 92
High5 EnergyGel (Plus) 0.79 1 116.46
Torq 1.25 8 91.2
Carboshotz 1 1 117
Squeezy Gel 0.92 12 70.65
PowerGel 1.2 5 90.83
Carb BOOM Gel 1 5 110
Multipower – Multi Carbo Gel 1 30 107
GU 1.5 1 66.67




Isostar Actifood 1.95 1 63.08
Lucozade Carbo Gel 1.1 1 67.27
mX3 extreme 1.97 1 37.56
Scientec Nutrition Over Blast 1.6 25 50
Overstim.s (Energix / Antioxidant) 1.73 10 120.23
Aptonia Energy Gel 1.45 1 206.9
Maxim Gel 1.39 1 58.27
Overstim.s (Coup de fouet / Red Tonic) 1.87 10 60.96
Isostar Gel Energy 1 4 114
Honey Stinger Gel 1.17 6 102.56


Sweetness and stickiness

These aspects may not seem of the highest importance, but they do matter. After running for a while, especially if the weather is warm, the stomach can easily get upset. And at that point the last thing you might want is a sweet and sticky gel. On the other hand, a strong sweet taste sometimes feels good when flirting with hypoglycemia. In any case, please remember that taste is personal. This is only to give you an overall idea and you must try them by yourself to make your choice.
Note that the percentage of sugar, although strongly related, is not necessarily proportional to the apparent sweetness. This is due to the use of various kinds of sugar (glucose, fructose), as well as other flavourings and acidity regulators. For example, I found the Carb BOOM gels very similar to the PowerGel, although they have only 11% sugar against 38% for the latter. Also, the Honey Stinger, despite being composed of 100% sugar, surprisingly doesn't taste too badly sweet.

Table 4: personal appreciation

Gel Flavour Sweetness Stickiness Personal mark










SiS GO Gel Subtle not sweet fluid *****
SiS Smart1 Gel Subtle not sweet fluid ****





High5 IsoGel Too strong sweet fluid *
High5 EnergyGel (Plus) Good (choc.) / too strong (citrus) sweet fluid ** / ****
Torq Very good (cherry) very sweet sticky ****
Carboshotz Good a bit sweet a bit sticky ****
Squeezy Gel Good sweet sticky ***
PowerGel OK sweet sticky ***
Carb BOOM Gel OK very sweet sticky ***
Multipower – Multi Carbo Gel Disgusting very sweet sticky *
GU Excellent (chocolate) sweet sticky ****





Isostar Actifood Good (fruit bits) sweet sticky ****
Lucozade Carbo Gel OK very sweet very sticky **
mX3 extreme OK sweet sticky **
Scientec Nutrition Over Blast OK sweet sticky ***
Overstim.s (Energix / Antioxidant) Good sweet very thick *
Aptonia Energy Gel OK painfully sweet very sticky *
Maxim Gel OK very sweet sticky **
Overstim.s (Coup de fouet / Red Tonic) Good (CF) / Too strong (RT) sweet thick **
Isostar Gel Energy OK very sweet sticky ***
Honey Stinger Gel Good very sweet very sticky *****


Conclusion

My final choice is a combo of SiS GO gel and Honey Stinger; the former to be used continuously, as they're easy to swallow and digest even in absence of water; the latter as punctual boosters or hypoglycemia killers. And obviously a couple of spare Crème de marrons for the mental.

Notes:
  • Surprisingly, High 5 EnergyGel composition varies quite a lot depending on the flavour.
  • No official weight is provided for SiS gels, they're measured by volume (ie. 60ml). I've weighted them myself for homogeneous comparison. I suppose the reason for that may either be that they consider them as liquid or that they want to hide their low energy-to-weight ratio.
  • Update 22/12/2008: Trail Goat at iRunFar posted today a similar test of his own, but more oriented towards the US market. You might want to have a look.
You can also browse the whole comparison table at a glance online or download the OpenDocument spreadsheet. These include a bit more information and links to official websites.

Ultra energy.