Precision Fuel & Hydration has a great reputation among endurance athletes for its no-nonsense approach to fuelling and hydration. To reflect that nutrition is highly individual, we asked two of our reviewers to test it, both using it over the last few months, each with their own style of training, racing and fuelling preferences. Our aim is to deliver a rounded, practical view of how the system works in real world conditions.
Megan James
I have to admit that for a long time I’ve been a “proper food only” person, and only more recently started incorporating carb drinks and gels into my longer running routines. It’s been a slow and often tricky transition – I’m not a huge fan of the tastes of many gels and I find my appetite for the constant sugary fuel to be often lacking. God bless the peanut butter and jam sandwich or snickers bars which for a long time have been my go-to for a long day out in the hills, however for both weight and energy level reasons I’ve found myself increasingly straying into the world of sports nutrition.
I’ve found with fell racing, the faster speed and heart rate required (compared to ultras), and my subsequent inability to chew and swallow without choking has meant I’ve run increasingly with stash of gels. For longer ultras and more self-supported challenges, I’ve found the sheer quantity of carbs needed for a longer run make sports nutrition a lighter and more convenient option.
So, when asked by RunUltra to review Precision Fuel & Hydration, I jumped at the chance, hoping that the word on the street of its ease of consumption and tailored fuelling plans would help me finally find a sports nutrition option that worked for me.
What was in the box?
I have to say I received an incredibly generous testing box containing large amounts of the following:
- 30g Carb Gels
- 30g Carb Gels with 100mg Caffeine
- 30g Carb Chews
- Carb only Drink Mix
- Carb & Electrolyte Drink Mix
- Electrolyte Tablets in 3x strengths – 500, 1000 & 1500
- 1x drink mix bottle
Given the size of the box and amount to test, it allowed me to test Precision Fuel & Hydration products in both training and on a number of longer ultra races, in both hot and cold weathers. My goal has been to try and increase my carb intake to 60g of carb an hour whilst racing and so I did push my gut tolerance in testing above what I have managed in the past. I tested all of the above, with the exception of the caffeine gels since my stomach has a high sensitivity to caffeine and I was pretty sure it would not induce positive effects in my racing – do try it though if you can tolerate caffeine though as I’ve heard good things from other runners who use this, especially in night races.
Precision Fuel & Hydration 30g Carb Gels
Let’s start with the stalwart of the runners fuelling, the humble gel. Firstly, I loved the fact these were 30gs of carb in each, with other brands I’ve used in the past struggling to get above 22g and therefore needed 3 an hour rather than 2 for the 60g target I was aiming for. Thumbs up.
The consistency is not as runny as some more liquid gels (SIS for instance), but not the sticky goo that gets stuck in the mouth with something like a GU gel. I personally found it easy to consume. The flavour initially tasted a bit funny, having been used to sweeter gels, but after the first one the mild taste really grew on me, and I found I was able to take quite a few onboard without feeling ill. I found out that, of all the products I tested, I got the most immediate energy boost from the gels, especially at the tail end of runs.
Having used the 30g ones in training, I actually went out on a limb and purchased the 90g “Jumbo Gel” pouch for my 110k race, wanting to go with little and often strategy, rather than having to sink a whole gel in one. I must say, I’d do this again – the resealable 90g pouch in a genius idea and saved me from lots of sticky gel wrappers hanging around in my bag.
One downside for me was the lack of sodium or electrolytes in the gels – I’m assuming deliberately as you are supposed to pair this with an electrolyte drink from their other products. However, as a heavy sweater I found I needed to supplement more sodium than usual when using the gels.
Precision Fuel & Hydration 30g Carb Chews
30g gram carb chews come in compact little packets, easy to stash, with 2x chews in each packet totalling 30gs. The chews come in 2 favours, original (which has the same mild taste as the gels) and lemon and mint. Like the gels, they are carb only and no sodium/electrolytes.
Precision Fuel and Hydration suggest their “high carb to weight ratio, is ideal for when you need to travel light” which is certainly true. They also suggest the lemon and mint flavours are specifically designed for training and racing in hot weather – I’m assuming due to the flavour being more refreshing as there is no difference in ingredients.
The texture of the chews is most akin to Turkish delight making them easier than typical chews of bars to eat whilst running. I did however find they had a tendency to get stuck on the teeth or in the mouth, so you definitely need a good drink to go with them.
Whilst they claim the same carb content as the gels, personally I found eating 2 chews to be more onerous, and the level of immediate energy from them less. The lemon and mint however were a welcome change and helped with flavour fatigue.
Precision Fuel & Hydration Drink mixes
The carb and electrolyte drink mix offers 60g of carb and 100mg of sodium across 1 litre of water (2x water bottles in a race vest). In comparison the carb only mix in the same ratios offers the same 60g of carb across 1 litre of water but no sodium at all. In addition, it suggests that the ratios of the carb only mix can be doubled to provide up to 120g of carb per 1 litre of water which certainly would kick a punch. I am assuming that the 120g of carb ration would be used if relying on drink mix only and not supplementing with other gels or food.
Trying both, they taste pretty much the same when used side by side, however I did find the stronger mix of 120g a bit too strong in taste. They were easy on the stomach and mild in flavour. I had no issues using them across an 18-hour period, although towards the end I did switch to 1 bottle of carb mix and one bottle of coke to change out the flavours. Given the lack of sodium in any of the other products I found the carb and electrolyte mix worked much better for me, allowing for 500ml of water per hour (30g of carb) and then only needed to supplement on top per hour with 1x gel/chew or real food equivalent. Racing, I found this a good ratio of solid to liquid food which made it super easy to hit my 60g carb per hour total, as well as keep my electrolytes topped up without having to find space for a separate electrolyte drink.
Precision Fuel & Hydration Electrolytes
I’m a pretty salty sweater so usually need more electrolytes than others.
In comparison to the electrolyte brands, I’ve used in the past which have around 0.8g of salt per tab, the lightest ones of 500mg come in just over half that, the medium 1000mg closest to the market strength, and the strongest 1500 electrolyte tabs super charged for hot days with high sweat loss. Personally, I found the lower 500ml ones nowhere near strong enough for my requirements but that is I’m sure based on my specific sweat rate. The Precision Fuel and Hydration website also has a good calculator which recommends which strength you should use based on a simple online questionnaire that I would I would recommend using to anyone that is not sure how to calculate how little or how much electrolytes they need.
Since for longer racing I tend to use carb and electrolyte mix I found these more usedful on short runs where I was didn’t need the fuel in addition and or was using other food, or post run to rehydrate effectively (for instance after an intense gym session). Otherwise, I found the carb and electrolyte mix the better alternative for the amount of water I was consuming. I did however race in UTMB Puglia in November, in about 20-degree heat, which I was certainly not acclimatised to, and so found them useful to up my electrolyte intake quickly.
I must say, the taste is not my favourite, I’d like a bit more flavour to mask the salty taste, but that’s personal preference.
Summary
The product range has a lot of pros. I have to say that overall I was highly impressed with the quality of the product and in general I was able to stomach pretty much all the products over a longer distance (for me the longest distance being 78 miles and around 18 hours 30 of running). The flavour is mild, not too salty like some mixes, also not sickly sweet.
On the downside, pretty much all the flavours, with the exception of the lemon and mint chews, is all the same, meaning that if using as your only fuel in a longer race flavour fatigue sets in. Certainly, on the longer races, I found interspacing with real (and savoury) food worked better for me than using the Precision range as a stand-alone. I’d also like to see some gels or chews with electrolytes in rather than having to supplement with extra tablets.
Cost wise, it’s not cheap – however buying the packets in bulk gives you much better value for money. Each gel comes in at £2.37 which is probably top end of what I’d be willing to pay for 30g of carb and double the price of popular SIS brand.
Overall, a professional product range, with lots of options for “mix and match” depending on your sport and personal body requirements. I love the fact you can get a plan tailored for you on their website, although I think always best to experiment and find out what works for you. For me I found the winning combination the carb and electrolyte mix in bottles, supplemented with 1x gel/chew per hour, plus real food from check points layered on top every 2-3 hours.
Dave Town
Precision Fuel & Hydration has become a regular part of my training and race fuelling over recent months, largely because of how simple and adaptable the range is. Rather than offering a single solution, the products allow you to separate carbohydrates and electrolytes and build a fuelling strategy that suits your own preferences and race conditions.
Across training runs and events, I tested a selection of their products, focusing on what felt easiest to consume during harder efforts and longer days.
Products Tested
- Carb & Electrolyte Chews (30g) – Original & Lemon/Lime
- Carb-only Drink Mix
- Carb & Electrolyte Drink Mix
- PF&H Gels
Carb & Electrolyte Chews (30g)
The Carb & Electrolyte Chews quickly became my preferred fuelling option. Both the Original and Lemon/Lime flavours are mild and easy to tolerate, even late into long runs or during higher-intensity efforts.
Compared to gels, I found the chews significantly easier to consume. They don’t require the same concentration to take on board, and I was more consistent with fuelling when using them. Although the gels were effective, I repeatedly chose the cubes because they felt more comfortable and less intrusive during running.
Each pack providing 30g of carbohydrate also made fuelling simple to plan, without having to think too much mid-run. These have now become the first item I make sure I have with me during races.
Carb-only Drink Mix
The carb-only drink mix worked particularly well as a pre-run fuel. It provided a noticeable energy boost without causing any heaviness or bloating, which can sometimes be an issue when taking on carbohydrates close to running.
This became a reliable option before key sessions and races, especially when solid food wasn’t appealing.
Carb & Electrolyte Drink Mix
During races, I used the carb and electrolyte drink mix in one bottle, alongside a second bottle of plain water. This setup worked well and allowed me to manage both hydration and fuelling without the drink becoming too concentrated or overly flavoured.
Having plain water available also helped prevent palate fatigue, particularly over longer efforts or in warmer conditions.
Gels
The gels performed as expected and caused no issues. They delivered energy effectively, but in practice I found myself reaching for the chews more often, particularly during harder sections when I wanted something easier to consume.
Overall Impressions
What stands out with Precision Fuel & Hydration is how straightforward the products are to use. Flavours are subtle, the labelling is clear, and the system allows you to adapt fuelling based on your own needs rather than forcing a fixed approach.
The Carb & Electrolyte Chews in particular have become a staple for me and are now central to my race-day fuelling. Overall, the range is well thought out, practical, and clearly designed with performance and usability in mind.
About the authors:
Megan James is a lake district based ultra distance runner and England Athletics qualified fell run leader. Running for local club Eden Runners she spends her time competing in local fell races as well as numerous ultras including Dragons Back, Cape Wrath and Arc of Attrition. Most recently becoming the 6th lady to complete the Lake, Meres and Water challenge she likes nothing more than a big adventure with friends out in the mountains.
Dave Town has various unsupported FKTs and has finished numerous UK ultra marathons including The Spine and Race Across Scotland.
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