UTMB Fuelling Guide: Ultra Running Nutrition Tips
UTMB in Chamonix is a 100+ miles of trail around the Mont Blanc massif, with big climbs, technical descents, exposed ridgelines and cold nights all asking something different of your body, hour by hour.
Getting round in one piece, and enjoying it, comes down to preparation as much as fitness. OTE-fuelled athlete Josh Beaumont shares what it takes to fuel and run an event like UTMB.
1. Recce the course beforehand
If you can, run as much of the course as possible before race day. Knowing which climbs are runnable and which need power-hiking, where the technical descents sit, and where to push or hold back takes the guesswork out of pacing. When you know a brutal climb is coming at kilometre 60, you can plan around it rather than being blindsided by it.
2. Don't go off too hard
Start lines are electric, and it's tempting to go out at a pace that feels easy in the moment. Resist it. Settle into your effort early and race the distance you've actually signed up for, not the first climb out of Chamonix. Ultra racing rewards patience — the runners still moving well in the final hours are almost always the ones who held something back at the start.
3. Set a fuel reminder
Don't wait until you feel tired or hungry to start fuelling — by then you're already behind. Set a reminder every 30 minutes so fuelling becomes automatic rather than something to remember when you're deep in effort and your brain isn't working as sharply.
This is where a reliable, high-carb gel matters:
- OTE Super Gels carry 40g of carbohydrate per gel — roughly double a standard gel, so you hit your carb targets with fewer gels to carry and fewer wrappers to fumble with when your hands are cold or you're mid-climb
- A maltodextrin and fructose blend — using multiple carb sources helps the body absorb more carbohydrate per hour
- Electrolytes included to support hydration, with natural flavouring from real fruit juice concentrate rather than artificial sweeteners or colours
For longer, steadier efforts through the day, OTE Energy Gels (20g carbs) or Energy Bars are worth rotating in alongside the Super Gels, with an electrolyte drink or hydration tab in your bottles to stay on top of sodium losses over a long day of sweating, especially through the heat of the afternoon sections.
Whatever you choose, test it in training first. Race day is not the time to find out a new product doesn't sit well with you.
4. Respect the climbs
UTMB is defined by its vertical gain, and trying to run every metre of it is a fast way to blow up. Power-hiking the steep stuff is often just as fast as running, and far more efficient. Save your legs for the runnable sections and, crucially, for the final stages of the race, when tired legs and a tired mind need to work together to get you to the finish.
5. Enjoy it
It sounds simple, but it's easy to forget deep into hour twenty. Trail racing is tough, and that's exactly why we do it. Take in the views, soak up the atmosphere in the villages and aid stations, and embrace the hard moments as part of the experience rather than something to just get through. The runners who remember the mountains, not just the suffering, tend to be the ones who come back for more.
The takeaway
Fuelling an ultra like UTMB isn't something to figure out on race day — it starts in training. OTE's range is naturally flavoured, easy on the stomach, and designed by sports nutritionists to work as hard as you do.
Whatever your next ultra looks like, explore the full range to build a fuelling plan that gets you to the finish line feeling strong.
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