Review: NUUN Active Hydration Tab

Tabs Splash

Finding the perfect nutritional balance for racing and training can be a never ending maze of mind blowing choices. The internet is full of scientific studies that hope to sway you one way or the other, a hive of fantastic and meticulously researched information awaits those that are struggling to find the perfect solution to their energy and hydration needs. Science has the answer... trust it!

When the chance to give a selection of NUUN Active Hydration tabs the 'UKXCNews race ready test' came up we decided to get as scientific as possible. That was until we realised that science wasn't our strong-point... so we just used them when we rode our bikes and wrote about what happened instead.

So NUUN Active Hydration tabs are your sugar-free, low-calorie, electrolyte source that, according to the website “contains the perfect balance of electrolytes and water without sugar to keep you properly hydrated for all of life’s pursuits”, and as we discovered, potentially the most useful weapon in your nutritional armoury.

So what's in a Hydration tab??

  • Review: NUUN Active Hydration TabsSodium helps regulate the total amount of water in the body.

  • Review: NUUN Active Hydration TabsPotassium is essential in the generation of electrical impulses in the body that control muscle and brain function.

  • Review: NUUN Active Hydration TabsMagnesium helps relax the muscles and prevents cramping.

  • Review: NUUN Active Hydration TabsCalcium is essential for muscle contractions and helps maintain a normal heart rhythm.

The idea is that if you maintain your optimum hydration level, you will be able to process the correct carb levels - using which ever gels, bars, etc you prefer - to better effect. And don't under-estimate the dangers of only slight dehydration. The Nuun website states "dehydration can occur after a mere 2% loss in body fluids leading to headaches, cramping and fatigue"... and we've all been struck by the dreaded cramps and mid-ride headaches that ruin training rides and can end races.

Tabs Dominoes

The potential for using an Electrolyte only mix to complement your race day and training regime are well documented, with many riders, from every echelon of XC racing, electing to using a combination of Electrolyte and Carb drink during a race.

One of our reviewers took the Cherry Limeade for a test ride and - as we like to make sure we race test everything - also used them at the recent Gorrick 12:12. Here is what he thought -

“I used the product during my last week’s training for the Gorrick 12:12 Torq in your sleep and also during the event itself. My plan was to use my normal energy products through the race and use the Nuun as an alternative when I was feeling thirstier or when having just taken on food. Nuun has been around for about 10 years now but the branding and image has recently been updated along with them adding a whole lot of new flavours to the line up. Firstly a bit about the product:

Nuun is a hydration aid, not an energy drink. That means it contains no carbohydrates (sugar) and so provides you with no energy. The main focus of the product is to enhance and flavour your water, which in theory will make you drink more, which in turn will help keep you hydrated so your performance won’t suffer. The other trick it has up its sleeve is that it contains essential electrolytes including potassium, magnesium and calcium, along with vitamin C and riboflavin. It’s also worth pointing out at this stage that some of the flavours contain caffeine, although it’s only 40mg per tablet (about the same as a cup of coffee).

The Tablets themselves are about the size of a pound coin and come in tubes of 12. They are currently available in 12 different flavours; the one I tested was Cherry Limeade which also has the added caffeine. All you have to do is simply drop one tablet in 500ml of water, wait 3-4 mins for it to dissolve, which is slightly longer than Nuun quote and then drink, easy as that. Nuun doesn’t have a strong taste, it just adds a subtle flavour to your water to take away the plainness which does encourage you to drink more. It also adds a very slight carbonated feel which again is a good thing as it helps with quenching your thirst. It proved a refreshing alternative to my usual energy drinks during the Gorick 12 hour race as I rotated through my bottles but as for the caffeine I’m not sure it had a massive effect on me but it didn’t do me any harm either.

Nuun is convenient, cheap, and is available in plenty of flavours and definitely encourages you to drink more water. Any percentage of dehydration is a bad thing so if you struggle to drink enough water when exercising or you find it boring and tasteless, I can recommend adding a Nuun tablet to your water to help keep you on top of your hydration levels.” - Jon Marshall

Nuun 1

To ensure we could form a well rounded opinion, we also asked another of the UKXCNews reviewers to give the NUUN Kona Cola a quick test. Although she didn't have time to race with them, Hannah gave them a thourough test on a couple of recent training rides...

“The Nunn kona cola hydration tabs contain 40mg of caffeine enough for a boost in energy levels during racing and training.

The taste is good with enough sweetness without being too sweet, this is good as I often find some of the flavours are too sweet and over powering.

I tested these on a hill repeat training ride. The first thing I noticed was that when I opened the water bottle it released a spray/gas a bit like a bottle of coke, this was a bit of a surprise and would be difficult to deal within a race situation when your breathing and working hard.

During the training ride I did eight hill repeats, sprinting to the top and recovering back down after each sprint I would have some of my drink. I only took Nuun during the whole ride and found when I got home that I still felt good and was well hydrated. The training session had taken an hour. I think on anything longer I would have mixed Nuun and plain water together and had two bottles as I found just drinking Nuun Kona Cola that I started to dislike the taste, this is mainly down to the fact I don't like coke.

It is very hard to tell on an individual ride basis whether a product is working, so I have tested it on a couple of training rides mixing one bottle with Nuun and one with water, this suits me better as I alternate between the two drinks.

Overall I think the hydration product is good, I would be keen to try other flavours as personally cola is not a flavour I enjoy.” - Hannah Attenburrow

Nuun Tablet Spill

To add another voice to our review, I took a tube (Lemonade) myself, and I also gave another one to a training buddy (Tri-Berry). We set about the hard task of enjoying a good solid week or 2 of nice warm rides, with a few turbo sessions thrown in for good measure. The results were again very positive. It made no difference to energy levels during the sessions but the feeling of hydration, and that of having your thirst quenched, was definitely noticeable. As a knock on effect, when combined with my usual post ride routine I did feel fresher and ready to ride again the next day. A slight carbonated taste, combined with a subtle yet agreeable flavour, seemed to do the job of exciting tired taste buds and keeping the dreaded dry mouth feeling at bay.

On a personal note, I've had a few experiences with different Electrolyte tabs in the past, and some have left me with mid-ride stomach cramps. I'm happy to say that the NUUN Active Hydration Tabs left me cramp free, stomach or otherwise.

To conclude, NUUN Active Hydration get a thumbs up from us. With a nice selection of flavours, there is bound to be one that will tickle your taste buds... A very handy weapon to have in your training and race day kit box!

Bottle with Tabs

For more info on NUUN Active Hydration Tabs and to see a complete list of flavours, visit

Photography: Peter Barker