Because water alone isn't going to cut it when you're training for endurance events
Whether you run, ride, swim or hike, science tells us that hydration and performance go hand in hand. Just 5% dehydration can lead to a 30% reduction in performance. So staying well lubricated is essential if you want to be at your best.
Water on its own is enough to keep your system hydrated as you go about the normal daily business of being alive, but as soon as you start to exercise and get a proper sweat on, you also leak vital salts, the most important of which are sodium and chloride. Failure to top up these essential electrolytes inhibits your body’s ability to absorb the water it needs.
Put simply, if your salt balance is out of whack you can end up peeing out all the fluids you put in. That’s why water alone when you’re going hard, long or in hot conditions doesn’t quite cut it.
For a full overview of the the various types of hydration available head to the bottom of this article.
We handpicked every suggestion on the list below for its combination of taste, effectiveness and convenience. But as with any sports nutrition, including energy gels, it’s important to note that what works for one might not work for another. So we definitely recommend putting our recommendations to the test to find your best hydration solution.
Best all-round option
SOS Hydration
Buy now: SOS (UK) / Amazon | £15.95
Carbs per serving: 3g
Salts per serving: 330mg sodium, 190mg potassium plus magnesium and zinc (quantities not listed)
A powder you mix into a 500ml (16 fl oz) bottle with water to create a hypotonic solution, the SOS Hydration sticks are the smallest we’ve tested and that makes them incredibly convenient. Not just for stashing in pockets but also for ease of getting into even the smallest of bottle openings. That can be a blessing if you’re stuck using a standard plastic bottle.
Each 5g sachet contains a fast-dissolving powder with an electrolyte profile that’s specifically designed for rapid rehydration. The makers claim this is the equivalent to an IV drip.
There are no artificial ingredients or preservatives and the five different flavours – berry, citrus, coconut, mango and watermelon – come from natural fruit for a decent freshness that’s not over sweet.
Saltstick Fastchews
Buy now: SaltStick (UK) / Amazon | From £2.99
Carbs per serving: 2g
Salts per serving: 100mg sodium, 30mg potassium, 6mg magnesium
Fastchews are a good solution for when you don’t want that faff of refilling bottles, when you want a change from drinking sweet hydration solutions or when you’re running a marathon or riding in a cycling event and relying on water from aid stations.
The chewable tabs comes in two flavours, lemon and lime or orange, taste surprisingly pleasant, a bit like fizzy sweets, and dissolve in the mouth – one benefit of which is faster absorption. They get their sweetness from natural stevia and the sodium is derived from sodium citrate, which has the added benefit of being kind to dodgy stomachs. And any endurance athlete will tell you how handy that can be deep into a challenge.
The resealable 10-tab pouches are easy to stash in a standard running belt and the pills don’t tend to crumble. But what we really loved about Fastchews is that you can also take total control of your dosing, topping up with small amounts of salt.
Nuun Boost Mango & Orange + Caffeine
Buy now: Nuun (US) / Amazon | From £20.63
Carbs per serving: 2g
Salts per serving: 350mg sodium, 100mg potassium, 15mg calcium, 25mg magnesium
If you prefer your hydration in the convenient form of an effervescent tab, Nuun’s range of fruity flavours are among the best and this caffeine-boosted variety provides hydration with a fatigue-beating kick in the pants.
Pop one of these classic tabs-in-a-tube into a 500ml (16fl oz) drinks bottle and you get a hypotonic solution with an added hit of 40mg caffeine that happily doesn’t suffer from a bitter aftertaste.
The lift is nice and steady rather than a surge, making these a good option for pre-race hydration on the morning of an event. Because of their low-carb content, other varieties in the Nuun line-up also make for a good way to pre-hydrate in the days before.
US only
Skratch Labs Hydration Matcha Green Tea and Lemon
Buy now: Skratch Labs (US) / Amazon (US) | From $19.50
Carbs per serving: 20g
Salts per serving: 380mg sodium, 43.8mg potassium, 46.9mg calcium, 39mg magnesium
It’s not easy to create sports nutrition products that taste fresh and real, or that you’ll still want to drink after you’ve been swilling them for hours, but Skratch’s powders, flavoured with real fruit, pull that off.
The portable stick packs are brilliant for refilling bottles with ease and when you mix them with 500ml (16fl oz) of water you get a lower-sugar hypotonic sports drink with a glucose/fructose ratio that’s optimised for faster absorption – the electrolyte profile actually matches what the average person loses in sweat.
They come in orange, lemon and lime, strawberry and passion fruit flavour while the matcha green tea and lemon flavour offers a 16mg bump of natural caffeine too.
UK only
Precision Hydration
Buy now: Precision Hydration (UK) / Amazon (UK) | From £9.99
Carbs per serving: 15-18g
Salts per serving: 500-1,500mg sodium, 250mg potassium, 48mg calcium, 24mg magnesium
Plenty of hydration solutions claim to boast the perfect balance of electrolytes and minerals, but Precision Hydration takes salt replacement to a precise new level. Its sweat-tested system helps you build a bespoke hydration strategy based on the salt you actually lose.
Once you’ve used the online tool to estimate salt loss (those who are really serious can also get an in-person sweat test done), Precision recommend a hydration tool kit to use for your chosen event. The range of lightly citrus flavoured tabs, hypotonic formula powders and pills deliver between 250-1500mg/l of sodium and can be combined to create a full pre, during and post-run hydration plan, optimised for the event and the conditions.
The higher sodium 1500mg/l sachets are excellent for pre-hydration while the electrolyte capsules – with 250mg of sodium and 125mg of potassium per pill – and the lower-carb effervescent tabs are fantastically portable and perfect for shorter races or those times when you might be drinking water from aid stations. The combination gives you total flexibility to choose how best to get your electrolytes and fluids on board.
Veloforte VIVO
Buy now: Veloforte (UK) / Amazon (UK) | From £5.50
Carbs per serving: 22g
Salts per serving: 350mg sodium, 240mg potassium
The only product on the list that offers a hydration solution from 100% all-natural ingredients, Veloforte’s brand new powders are head and shoulders the freshest and tastiest on test.
Made from a combination of freeze dried real fruit, dehydrated coconut water and Himalayan Pink Salt for the natural electrolyte hit, they come three flavour combinations – Peach, Raspberry & Rose-hip, Strawberry & Basil and Golden Apricot & Sage – that are unlike anything we’ve ever tried.
Mixed in a 500ml (16fl oz) bottle, each 24g sachet creates a hypotonic hydration solution that’s so real you can still see bits of fruit floating around in your bottle.
There are three options. The low-carb SOLO is great for general hydration in the build up to an event while VIVO provides fast rehydration with a small hit of energy and ATTIVO comes with a 75mg kick of natural caffeine from guarana.
Xendurance Hydro-X
Buy now: Xendurance (UK) / Amazon (UK) | From £26.95
Carbs per serving: 2.1g
Salts per serving: 300mg sodium, 200mg potassium, 136g calcium, 71mg magnesium, 270mg chloride
Designed to be mixed with 475ml (16fl oz) of water to create a hypotonic drink, HYDRO-X can be used as a pre-hydration energy top-up or as a source of hydration and fuel during exercise. But this isn’t just your average sugar plus salt combination.
Tapping into new research that suggests far from being the enemy of endurance, lactate is actually essential to performance – it’s used by the body 90% of the time as the preferred energy fuel over glucose – this powder mix contains 1,500mg of lactate per serving that helps lower muscle acid and muscle burn and reduces muscle soreness.
A patented hydration technology, Sustamine with L-Glutamine and L-Alanine dipetide, claims to enhance electrolyte and water absorption in the intestines, stimulate glycogen synthesis and promote the building of muscle protein to help in the repair and recovery of muscle tissue.
The lemon citrus flavour is as palatable as other hydration mixes, though don’t expect real-food freshness, and sadly there are no stick packs or sachets, so if you want to use for longer events you need to decant it into a suitable vessel.
Totum Sport
Buy now: Totum (UK) / Amazon (UK) | From £18
Carbs per serving: 0g
Salts per serving: 8084 ppm sodium, 2654 ppm magnesium, 784 ppm potassium (parts per million in liquid form)
Totum Sport is unlike any other product on this list. Each small easy-to-open sachet of hypertonic liquid contains 78 essential salts and minerals harvested from beneath plankton blooms in nutrient-dense areas of the ocean.
As you’d imagine, this unapologetically salty liquid doesn’t taste delightful but that’s the trade off for a balanced combination of minerals that do more than just help with hydration.
The 100% natural minerals also preserve blood glucose levels, delay the switch to anaerobic metabolism – reducing lactate production – and minimiae muscle fatigue. They’re brilliantly portable too, and don’t need to be mixed, though you’ll likely want a swig of something to take the taste away after you down one.
Hydration products explained
There are loads of products that can help you stay on top of your hydration no matter what challenges you take on. These come in many forms: fizzy (often fruit flavoured) tabs and powders you can add to your drinks bottle, capsules, chewable pills, ready-bottled sports drinks and even sachets of liquid electrolyte solutions.
So how do you know which hydration solution will work best for you? Well, for a start it’s important to understand that not all hydration products work the same way. When it comes to those you drink, the concentration of the liquid changes the rate at which they’re absorbed by the body.
Remember those science lessons from school where you learnt about osmosis? Those principles apply here too. The concentration of your hydration drink affects how rapidly it passes through the cell walls and into the blood.
Isotonic drinks like like Lucozade Sport and Gatorade have between 4-8g carbs per 100ml which also supplies energy but this means they have a similar concentration to human blood and are absorbed at roughly the same rate as water. They aren’t optimised for hydration but can be good for replacing energy and electrolytes at the same time.
Hypotonic products tend to be low in carbs – typically less than 4g per 100ml. This means they have a lower concentration than blood and are absorbed more rapidly. These are the best option for hydration alone.
Finally, hypertonic solutions have the highest quantity of carbs – 4-8g per 100ml – and a higher concentration than blood. They’re taken up more slowly than water and tend to be used mainly for energy rather than hydration. The electrolytes are a bonus.
Of course, any good hydration product needs to be convenient to carry and to use, and taste good too. So we’re constantly testing the latest electrolyte tabs and hydration powders to bring you the products that tick those boxes.