What's it really like to run UTMB?

It’s a bucket list race for many, including me. This year Amber Wood got to run Ultra-Trail du Mont-Blanc.

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Amber and Matthew cross the line in Chamonix.

I’m meeting Amber Wood not quite four weeks after she and her brother Matthew completed the 170+ kilometre UTMB Mont-Blanc, an epic race held in the Alps with near enough 10,000m of elevation.

The first thing I want to know is how she’s feeling after such a physically gruelling adventure. The answer is, pretty good. “I’ve just recovered really quickly. I clearly didn't put enough effort in… but that’s because I was asleep half the time.”

It’s a neat summary of one of the big challenges of a race like this - how do you cope with the sleep deprivation? It was a dream race for Amber, so maybe it’s appropriate that she spent parts of it dreaming.

Staying awake was not the only challenge. Amber also had the crowds, the nutritional challenge, the weather and the sheer brutality of the course to contend with.

So what’s it like to run one of trail running’s blue ribbon events? Amber let me in on a few secrets.

Sleep deprivation

Staying awake for 45 hours would be enough of a feat, but the race actually starts in the evening which means Amber and Matthew had a full day to kill before they hit the start line.

“We started just before 6pm and I'd been awake since about 7am. I didn't sleep during the day, so that's 50-something hours awake, apart from a couple of naps,” she says.

It wasn’t just the hours on her feet that were a challenge. “I think the tiredness was because of altitude. I noticed, even on the first couple of climbs, that as we were climbing up, I was thinking, ‘Oh, I can't keep my eyes open, I’m almost going cross-eyed.’ And then when I get back down again I'm like, ‘Ah, I’m clear headed and feel fine.’

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“But as the race progressed and my tiredness increased, the two [the effects of the altitude and the time on legs] converged and then I was permanently half asleep. That was frustrating because I felt like it wasn't my fitness that was holding me back. It was just trying to stay awake.

“I was literally asleep, literally dreaming. At one point, I half twisted my ankle and woke up and I was like, ‘Oh, where am I?’”

Sleeping on the job’s not all downside though. “There was one climb that Matthew said went on for so long, and for me, it was about 15 minutes because I slept through it, which is a bit scary.”

This altitude-induced sleepiness was a feature of the race throughout for Amber. “I first noticed it couple of hours in. That was a bugger.”

She did get some naps in though. “I don't know, what aid station it was, but it was after Courmayeur so it was after 100Ks, somewhere. I stopped and slept on a bench for 10 minutes or so. I was pretty uncomfortable. I probably only just got into sleep and then came back out, but it did make a big difference.”

Sleep where you can. No matter how uncomfortable it may be.

She had planned to have a more substantial sleep at the aid station at Champex-Lac, 128k into the race. It was an interesting experience, definitely not pristine. “They had a tent with mattresses. I was in there for a while, I probably got about 20 minutes sleep, waking up every little while because my feet were killing me.

“I was in my running gear under a doona that so many other people had already slept under. Someone else's head torch was there. But after that I was a lot better.”

By this stage, Amber knew daylight was not far off. “That really picked me up. I feel like after the sun came up it was a whole different race. I was in a lot of pain, but I knew I was going to get to the end.”

The obvious answer to falling asleep is caffeine. But how to manage that while running through the Alps? “Drop by drop in a gel. I did have a couple of coffees, but I was worried about my stomach so I didn’t do that as much as I probably needed to. So then Matthew was just feeding me caffeine blocks.

“He said I was like a slot machine. I'd have one. And then I'd be like, ‘Yep, I'm all right!’ And I'd be marching on, and then after a while, he'd be like, ‘Where’s Amber gone?’ And I'd be back there like, ‘Oh, I'm falling asleep again.’ So he’d give me another block and I’d wind up again.

“When we looked, those blocks don’t actually have that much caffeine. It's amazing how much a little bit can do when you're that depleted.“

Not all there

Towards the end of the race Amber starting losing her grip on reality. “I felt quite disorientated a lot of the time. There were times when I thought, ‘Oh yes, I’ve run this track before. I remember coming here with the kids.’ And then going, ‘Hang on, what country am I in?’

“So I was kind of not all there. At one point, it was like waking up from a dream and just trying to hold onto the information. I remember climbing up out of Italy and thinking, ‘There's something about this track that we're on. I can't remember what it is … was it something about women? Why are there all these men on the course, then?’

“They were random thoughts and that frustrating sense of knowing something, but not quite being able to remember it.

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“I knew where I was, but there were times when I was definitely confused and having trouble working out what was going on. I kept having the sense that I'd been there before, even at the very end. The second last descent, you come down this hill, it's really, really technical, and there's this massive boulder that really stands out.

“I was like, ‘Yeah, I've been here before.’ But I couldn’t figure it out. And then I realised, because I'd watched so many videos of the course, I was remembering what I'd seen on those videos. And I was like, ‘Oh that makes sense. Yeah, the reality is what's happening now.’

“I did have hallucinations. When I was coming up to Champex-Lac and I knew I was going to have a sleep, there’s this massive climb, and as far as you can see in both directions are other runners’ headlights. But I kept thinking, ‘Oh yeah, there's a hotel just there. I've just got to get to the hotel and then I can have a sleep.’

‘And then when I did get to the top of that hill, it was just a shearing shed and it was really muddy and it smelt of sheep poo. There was no way I was lying down there.”

Horrendous weather

Like all trail races, UTMB is weather-dependent. And Amber experienced memorable conditions - for all the wrong reasons. Of the 45 hours she was on course, 14 of them were “horrible”, featuring torrential rain, hail and - in some places - snow.

“It was just ridiculous. Coming up one of the first climbs it was snowing. Snowing and miserable and so muddy. Like, I'm talking, so much mud.”

What do you do when you see mud on the trail? Well most of us run around the mud, right? Which is fine if you’re on your own. Not so much so when you’re one of thousands of runners on the trail.

“The course had been chewed up, and so then the little tracks on the side had been chewed up, and then the grass in between had been chewed up, and then everything on both sides of that had been chewed up.

“So then there was just nowhere to go. And I remember thinking, ‘Oh, if this was Australia, they'd just call it off. And then we found out that they'd changed the course. So that at least made sense.”

The runner who made this video, Phil, was running at around the same pace as Amber, finishing about 45 minutes after her. His experience gives a good insight into exactly what running UTMB as an “average” runner is all about.

The rain was so heavy, it turned some of the climbs into waterfalls making it almost impossible to stay dry. That brought another problem to the surface - the cold.

“When it was raining I remember thinking we should stop and put some warm clothes on. We weren’t cold at that point, but I know we were about to climb. We didn’t do it, and halfway up we were soaking wet and there was nowhere to stop that was dry.

“We came across a sign and there were hoards of people milling around this sign trying to use it to shelter from the rain so they could throw dry clothes on. But we had to put our stuff on the ground - it all got soaking wet.

“So that was a mistake, and that was in the first third of the race. It meant all night our hands were freezing. It was a bit rough. On the first night, I was trying to pull my beanie down and then pull my buff up like a balaclava because I needed to be able to cover my face.

“And I was trying to tuck my face under my raincoat so I could breathe some warm air down onto my body. My core was warm, but my my face and my hands were cold. So, it was a strange kind of cold.”

The impossible race

Going into the race, Amber knew it would be a huge challenge and it didn’t disappoint. This course is tough in great conditions. In poor weather, it’s a beast.

“In the middle of the course the race just felt impossible. It was just like, this is ridiculous - it's just not actually possible to finish. It was so huge and taking so long. It just seemed way too slow. And part of that slowness was the conga lines of runners in front.

High in the Alps.

“It was really hard to get any kind of rhythm. As a run, it was a fairly crap experience because we couldn’t get into our own groove and our own pace. Most races start with a little buzz of excitement, and then the field spreads out. Then you just settle in and you can get your groove on. Here we just never got that sense.

“Even the few sections that were quite runnable were was on these narrow little tracks that were really deeply grooved by cattle, and you couldn't get past people. It was frustrating.”

One tip for new players is don’t be at the back of the pack at the start line. “I think if we had pushed further up at the start it would have been better. We didn't want to wait for ages [in the starting corral], so we came in from the back and pushed our way in a little bit.

“But it took three minutes from when the race started for us to get to the start line. Being that far back just meant it was way more congested. And that was the case right the way through the race. It was just conga lines all the time.”

Run some, hike most

Partly due to the sheer number of people taking part, and partly due to the horrendous conditions, much of the course simply wasn’t runnable. “It was mostly hiking. All the downhills we ran, except for the ones that were too slippery. So on the first night, there were some we could run.

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“But we were still running most of the flats and downhills right through to the end. I was really proud of that, because I really felt like my fitness was not a limiting factor.

“Pain was [a limiting factor]. On some of the really technical stuff at the very end - really technical - because you cannot land flat, I had blisters and all sorts, and it was just so painful landing, having to plant your foot at weird angles. But my legs, my quads and everything felt fine.

“A lot of it was hiking because there were bits that you couldn’t run even if you wanted to. Climbing up Les Tseppes the grade was over 30 per cent, weaving around rocks. It was insane. And that was in the last 15-20k of the race.

“The finish is brutal. You climb Les Tseppes and then you come back down. But it doesn't just come straight down, you wind around a bit. Then it's fairly flat, but then you drop all the way down into town.

“Then it's runnable for a bit, but then you start climbing again. Then you go down this really technical stuff, and then you have to climb again, and then go down for another seven kilometres. I was like, ‘This is so cruel!’”

This year’s race had all kinds of weather - rail, hail, snow … and some sunshine too.

Unique atmosphere

The end of the race might be cruel, but the start line atmosphere was incredible. “It was things like that that make it all worth it. The running was frustrating, but the event as an experience was just mind blowing.

“There were people lining the track for the first 10 kilometres and crowds of people really packed on each side of the course. It was like being sent off to war or something. It was like we were heroes.

“It was crazy, but it was a bit intense as well. It thinned out a little bit as we started climbing, but then we dropped down into Saint-Gervais and they had a full on DJ.” An Australian DJ, no less.

“There were people from the village partying on the sides of the road. I was in the aid station and I was thinking, ‘I actually have to get out of here because this is really intense. It's too weird.’

“The crowds did drop off after that, but then at times you'd just be running along and suddenly there'd be loads of people all on the side of the track cheering. It was really surreal. You would never, ever get anything like that in Australia. Nothing. No other race that I could think of.

“It was exactly like when you see footage of the Tour de France, people just lining the path and then they're on the path, because they all want to see you as you're running. Then they get out of your way as you’re running through, but not really!”

The atmosphere at the event exceeded Amber’s expectations. “You see it in videos but until you're actually feeling that vibe … it was incredible. Even the race week leading up to it. The town was just heaving but it was a really nice vibe. Nice being somewhere where you’ve all got the same thing going.”

The race finishes in the centre of the French ski resort of Chamonix, which Amber says was awesome, if a little cramped. “There were people sitting around having lunch in the cafes. You run straight through town and everyone's cheering you on.

“Once you drop out of the forest on the approach to Chamonix, you get a real boost and then you’re running alongside the river. And you get this vibe. It's like, ‘Yeah, I can run. I've got all this energy again.’

“Then you cross the finish line and there’s a big archway, but then there’s no space. So you run through the arch and then you have to stop, and then there were people sort of milling about and people trying to get you to move on. And we were trying to get our finish line photo.”

Aid stations

UTMB’s aid stations also had a vibe all their own. “They ranged from a party, like a nightclub involving the whole town, to a sheep shearing shed on the top of a mountain. Most of them were really well set up with food. Even the smaller ones had enough that you could get what you needed.

“But the big ones had loads of choice. They were pretty hectic. There was nearly a fight in one of the earlier ones… I thought someone was going to start swinging punches. It was jam packed. You couldn't move in there.

“There were no chips, which was sad. That's my staple. They had bread, tomato and cheese, that sort of thing. Strangely, I ate lots of cheese which is weird because I would never normally eat cheese during an event.

“But they had this really nice Swiss cheese or something at the aid stations. That was nice because it was so different flavoured to anything else. And then pastries and soup. Veggie soup and you could choose rice to have with it. It was different.”

The aftermath

Amber was surprised how good she felt after the event. “In the context of having run 170 kilometres, I felt really good. But my elbow was very sore from using my poles. I was in pain from about 15 kilometres onwards.

”This started so early on in the race, I couldn't believe it. It got to the point I couldn't bend my arm. I had to put my arm out straight to be able to use the poles because it was so painful.”

The amazing scenery is one of the many things that makes this race special.

Amber saw some people on the course who’d gotten to the point where they just couldn’t run. “Everything had locked up, their quads had locked up and everything. And I just did not feel like that. I was tired and it was hard to wind up again, but I can't remember any muscles really standing out as being like a limiting factor.

“It was more just the overall feeling of I’ve been on my feet way too long and everything hurts now. I don't want to hurt anymore.”

Despite the elbow pain, the poles - which she’d never used in an event before UTMB - were beneficial. “They made a big difference - I'm converted now. They helped stabilise me and on some of those big climbs I was able to plant them and it was like having handrails, almost. Four points of contact rather than two.

“Even coming downhill, I could take some of the weight on the poles so I wasn’t quite as invested if where I was landing was a bit dodgy. And they stopped me from falling over when I was falling asleep!”

So there you have it. UTMB - brilliant and brutal. And the bits you’re not asleep for you’ll remember forever.

Upcoming Events

There are way too many events for me to list everything that’s happening around the country, but here is a selection of upcoming races (with a bias towards South East Queensland).

Event

Location

Date

Afterglow Twilight-Night Trail Run

Torquay, VIC

6 December 2025

Beerwah at Daybreak

Beerwah, Qld

7 December 2025

Mt Buller Sky Run aka Santa’s Run

Mt Buller, VIC

7 December 2025

6 Inch Trail Marathon

North Dandalup, WA

21 December, 2025

Aussie Alpine Backyard Ultra

Falls Creek, Vic

31 December, 2025

Glasshouse Standing Backyard Ultra

Sunshine Coast, Qld

31 December 2025

Tamborine Mountain Relays and Marathon

Tamborine Mountain, Qld

25 January 2026

Beerwah at Night

Beerwah, Qld

31 January 2026

The Running Calendar website is a great source if you want a comprehensive understanding of what’s available aro