Ultra trail fuelling strategy: how Josh Wade fuels 171km and 10,000m of climbing.
How Josh Wade fuels 171km and 10,000m of climbing — and how to build your own strategy.
UTMB is 171 kilometres, 10,000 metres of climbing, and anywhere from 20 to 40+ hours on your feet. Over that distance, the winner isn't only the strongest climber — it's the runner who can still take on fuel at hour 15 when everyone around them is falling apart. In ultra, fuelling is the second discipline.
SiS athlete Josh Wade races UTMB on a fully-planned carbohydrate strategy, built and rehearsed over years of gut training. This pack breaks down exactly what he takes, checkpoint by checkpoint — and, just as importantly, how to scale it to your experience, because his numbers are elite and not where most runners should start.
Josh runs the whole race on Beta Fuel — no solid food. His entire in-race system is drink mix and gels, because at race pace there's no time to lose fiddling with anything complicated at an aid station.
Delivers 80g of dual-source carbohydrate per serving in a single bottle. Dual-source carbohydrate (a maltodextrin:fructose blend) uses two different absorption pathways in the gut, allowing a far higher rate of carbohydrate to be absorbed and oxidised than glucose alone. Over an ultra — where total energy expenditure runs into the thousands of calories — that higher ceiling is what keeps power and pacing intact deep into the race. Josh carries two bottles at a time, giving 160g of carbohydrate ready to drink between checkpoints.
Delivers 40g of dual-source carbohydrate per gel in a smooth, easy-to-take format. Gels let Josh top up carbohydrate on the move without stopping — essential on technical climbs and descents where drinking from a bottle isn't always practical. Rotating gels with the Beta Fuel drink is how he stacks intake toward that 120g-per-hour target while keeping his stomach settled.
Delivers 40g of dual-source carbohydrate plus caffeine per gel. Caffeine has strong, consistent research evidence for reducing perceived effort and delaying fatigue — most valuable when fatigue is greatest. Josh saves his caffeine gels for the back half of UTMB, when the climbs are relentless and mental sharpness matters as much as the legs. Test your caffeine tolerance in training first; individual response varies.
Josh boxes his nutrition by aid station so his crew can restock him in seconds. UTMB runs anticlockwise from Chamonix, with crew access at four points.
| Leg | Distance | Strategy |
|---|---|---|
| Start → Les Contamines | 0–31 km | 2 × 500ml SiS Beta Fuel 80 + Beta Fuel gels. The race settles in — Josh starts fuelling immediately, not when he feels he needs it. Les Contamines is the first crew-assist point, so boxes are ready to swap. |
| Les Contamines → Courmayeur | 31–79 km | Beta Fuel 80 bottles + Beta Fuel gels. The first big, remote block — nearly 50km over four high passes into Italy. A disciplined intake ceiling pays off here; Courmayeur is the halfway point and a key crew stop. |
| Courmayeur → Champex-Lac | 79–125 km | Extra Beta Fuel loaded at Courmayeur. The crux — 46km with no crew access except a fluid point at La Fouly, where most UTMB DNFs happen. "There'll be more product at Champex-Lac … I'll have to carry more from Courmayeur to get me through." Fuelling here is survival, not optional. |
| Champex-Lac → Vallorcine | 125–149 km | Beta Fuel + Caffeine gels come in. Into the final third — three brutal climbs and descents on legs that have already run 125km. The carbohydrate keeps the engine fed; the caffeine keeps the mind sharp. |
| Vallorcine → Chamonix (finish) | 149–171 km | Beta Fuel + Caffeine gels to the line. The climb from Vallorcine to La Flégère — 1,200m of gain after 150km — is where the race ends for many. Josh keeps fuelling to the finish: "you need the energy to do that," and the energy comes from never having let the fuelling slip. |
Josh's ~120g of carbohydrate per hour is an elite number, built over years of gut training — and in his own words, it's not where most runners should start.
| Your level | Carbs / hour | How to get there |
|---|---|---|
| No gut training yet | ~40g | Roughly 2 isotonic gels an hour. Safe, settled, and enough to keep you moving — Josh's own starting recommendation. |
| Some gut training | 40–80g | Mix Beta Fuel drink with gels. Build up gradually across your long runs; don't jump straight to the top of the range. |
| Fully gut-trained / elite | 100–120g+ | Josh's race intake. Only reach here after months of progressive gut training — this is a trained adaptation, not a race-day decision. |
Josh's biggest performance leap didn't come from a new shoe or a bigger training week. It came from teaching his stomach to absorb more carbohydrate — and it took years, with some hard lessons along the way.
Josh has been sick at UTMB before from being too aggressive too soon — which is exactly why he's clear that the big numbers are earned, not copied. The principle for every runner is the same: practise your race-day fuelling in training.
Over 15, 20, 30 hours, your body relies on both fat and carbohydrate — but it's your stored carbohydrate (glycogen) that lets you push the pace, and it runs out fast. Without a constant, well-drilled supply, energy — and the ability to hold pace — falls away. Josh puts it plainly: at 40g an hour in his early days, over 10-plus hours, "I just would not have the energy." The higher, gut-trained intake is what lets him stay strong when the race is won and lost — in the final third, on tired legs, hours from the finish.
Whatever your level, the lesson from Josh's UTMB is the same: decide your fuelling strategy before the start, rehearse it until it's automatic, and trust it on race day.
Product intake described reflects Josh Wade's personal, gut-trained race strategy. Always build carbohydrate intake progressively in training and find the level that works for you. Test caffeine tolerance before race day.