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High5 2:1 Energy Source is carbohydrate-based drink powder, available in small sachets or big tubs. We reviewed this product back in 2010, and some of what we said still holds. Since then, it's not clear if the actual formula of the drink has changed, but the product has been re-launched with a 'new generation' tag, and new claims regarding performance that are quite astounding.
According to the High5 website and other publicity material, Energy Source can help you: 'Go 26% further at the same speed' and provide '15% more power over 40 miles', both with 'no additional training and overnight improvement'. Information on the website gives more details on the science and independent studies that back up these claims.
So where do these improvements come from? According to the boffins at High5, it's all to do with the proportion of glucose and fructose used in this drink. Whereas many energy products deliver the carbohydrate you need in the form of glucose alone (or with a dash of fructose), Energy Source delivers glucose and fructose in a 2:1 ratio.
So what's the thinking? Using glucose-only products as a source of carbohydrate, most cyclists (or any athletes) can absorb only a limited amount - usually around 50g to 60g per hour, depending on weight, age and other similar factors. High5 say that fructose can deliver more carbohydrate to the muscles, in addition to that provided by the glucose. Put in the simplest layman's terms, the fructose goes in another way, bypassing the mechanism that usually limits carb intake to 50/60g per hour. The end result: you can increase your carb intake by up to 50%, giving a total of 75g to 90g per hour, according to High5. And that means you can go faster, or further, or both.
Of course, not everyone will see these improvements (for a start, it's not just a case of necking a few bottles of drink any old time - in an accompanying Nutrition Guide booklet, High5 advise on exactly how and when to drink Energy Source before and during exercise), but I have used this drink on a lot of long rides and sportives, and I can say it definitely works for me - although whether I'm increasing distance or power by the percentages stated I just don't know.
And yes, it could be other factors that help me go well, but I would still highly recommend trying Energy Source, to see if helps improve your own performance.
The taste is sweet but not too sticky, and the available flavours ('fresh citrus', tropical, orange and 'summer fruits') are pretty refreshing too, so it helps you stay hydrated - another simple way to improve performance. The ingredients also include sodium and potassium - two of the key minerals required to replace those you lose via sweat.
As with all nutrition products, it's important to sample Energy Source on a training ride first rather than an important race or sportive, just in case it doesn't agree with you.
A word of warning: Fructose is not a wonder drug. You can't take increasingly large amounts and expect to go increasingly fast. There are limits to the amount your body can absorb - usually 20-30g per hour. In addition, high fructose diets can cause an increase in blood fats, so some nutritionists recommend that fructose should be no more than 10% of your total daily carb intake.
And don't forget, while you're taking on those extra carbs in a race or sportive, you still need to do all the other sensible things like hydrate properly and replace electrolytes, and consider protein intake if you're doing longer events. A bit of training on the bike is pretty essential too.
Energy Source drink mix is available in a 2.2kg tub for £25.99 from the High5 website, and in a box of 12 sachets (each 50g) for £10.99, though you can find cheaper deals at other on-line stores.
A good-value and effective energy drink, with a glucose:fructose mix that seems to improve performance if used correctly.
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Make and model: High5 2:1 Energy Source drink mix
Size tested: Citrus flavour, 2.2kg drum
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
The High5 website says Energy Source is "a high carbohydrate drink mix for maximum energy. Energy Source is rapidly absorbed and highly stable in the stomach even during intense race effort. Its real fruit flavours are mouth watering, light and not too sweet."
Most of that is fair enough, although I found the taste pretty sweet - although not as sweet and sticky as some other energy drinks.
Tell us some more about the technical aspects of the product?
The High5 website has a lot of infomation about the science behind the claims (although some of the links lead nowhere).
I have used this drink on a lot of long sportives, especially in the first part of the ride, usually before switching to something containing protein in the latter part, and I can say it definitely works for me.
Compared to many other nutrition products, the price of Energy Source is good value.
Did you enjoy using the product? Yes.
Would you consider buying the product? Yes.
Would you recommend the product to a friend? Yes.
Age: 50 Height: 5ft 10 / 178cm Weight: 11 stone / 70kg
I usually ride: an old Marin Alp My best bike is: an old Giant Cadex
I've been riding for: Over 20 years I ride: A few times a week I would class myself as: Experienced
I regularly do the following types of riding: touring, club rides, sportives, general fitness riding,