If climbing mountains or hitting the slopes feels too boring, I have just the sport for you. Ski mountaineering (or ‘skimo’ racing for those in the know) is a niche endurance challenge that combines hiking up and skiing down mountains. Events range from sprint circuits and short courses, to partnered relays, long distance and purely vertical bottom-to-top courses.

“It's the only sport that I've been able to push so hard that you get that taste of blood in your mouth. It is quite hard if you push yourself, but it's interesting. I would say it's probably one of the sports with the least amount of diversity because there's lots of barriers to entry.”

Sam Hill, who previously focused on ultra running (specifically mountain and sky running, plus a side of rock climbing), is a ski mountaineer who was tackling the Patrouille des Glaciers before his race sadly got cancelled due to weather. We worked together on his fuel and hydration strategy for a prep race in Colorado and then for his planned A-race for the season. While the same foundational principles of race nutrition apply, there are certain logistics and considerations that have to be factored into a skimo plan.

What’s the biggest challenge when it comes to staying on top of your fuel & hydration strategy?

"It’s the combination of the fact that often you might potentially be in fairly technical terrain and as well as wearing gloves, you also have two ski poles to be using. It’s not like running where you feel very connected to the terrain; you've got skis on your feet and solid boots. There's lots of balance at play… so you really need to judge when to eat or drink. It’s just more of a ‘thing’ if you need to drink or take something out of your bag… taking one hand off your poles for a few steps costs you a lot of time as well as energy and balancing. There's quite a few steps before you can actually put something in your mouth."

Even non-skimo athletes can run into logistical problems trying to fuel and hydrate, such as cyclists tackling a technical terrain. Combined with the mental aspect of having to focus on the road (or mountain) ahead, staying on top of your planned intake becomes that much harder.

"The mental barrier to eating also becomes greater because you know that you have all of these steps to go through. The inclination is to not do something when it becomes difficult, especially when you're tired. You have to try and make it as easy as possible for yourself. It’s also just being quite strict with yourself and anticipating when things are going to be easier or harder."

For Sam, fueling ‘on the go’ during a ski mountaineering race logistically includes keeping fluids from freezing by tucking it down his shirt and only taking in carbs and electrolytes on the climbs before flying down the hills.

"Because of the downhill element of it on the skis, you're travelling a lot and not using too much energy, but you can't eat or anything like that. I just literally can't do anything when I'm skiing. Maybe the first little bit of the ski down, but our first ski down will be in the dark and my race partner and I will be roped together on the glacier. There's lots of stuff going on!

"So I have an alarm on my watch which goes off every 30 minutes for fueling. But that'll just be relevant on the uphill sections. And then usually at the bottom of the downhill section, there tends to be an aid station where you can refill before another three hours on the move."

Balancing all of these logistics, all while staying physically balanced during a race is part of the appeal of the sport and one of the reasons Sam ventured toward instead of away from the challenge.

What got you into ski mountaineering?

"I think it's quite an interesting sport because it has so many different skill elements. You have to be able to ski downhill relatively well because of the kind of terrain that you're in, but also the kind of equipment you use is very light, which makes it harder to ski. And then the ‘skinning’ (which is when you're on your skis going uphill) – it seems like quite a logical thing to do but there’s a lot of technique behind that as well. It also takes you into big mountains, so you have to have skills to deal with crossing glaciers, climbing up snow, ice, using crampons and ice axes."

Even though Sam is on the more niche end of the sport, a shorter, more ‘constrained’ version is actually featured in the winter Olympics.

"It's a winter Olympic sport now, but the winter Olympic events are a very small part of what the sport is because it has to be quite a controlled, spectator friendly environment. Like this race that I'm doing in Switzerland would never be able to be in the Olympic event because it's up in the mountains, it's too big, it's too long, etc."

You mentioned using crampons and ice axes – what all are you required to carry?

"There’s always a kit list and because of the glacier, we have to take rope and harnesses, etc. Mandatory clothing's fairly light actually, so the bags aren't going to be as heavy as other races, but there's still a minimum amount of equipment you've got to take… But I'll take as little as possible."

Any tips and tricks you’ve learned for how to carry everything? This is always a big question in endurance sports, and ski mountaineering sounds like one of the tougher situations!

"A lot of ski mountaineering races tend to be fairly short, like three to four hours. But doing the longer race in Colorado really showed me there's more logistical things. I'm going to experiment with actually wearing a really small running vest underneath my backpack. This way I'm able to keep bottles warm but they’ll still be right on me so I can drink. Ski mountaineering backpacks don't tend to have pockets for food like running vests do. So again, having food upfront is really important as well."

What are ski mountaineering kits usually like in comparison?

"The skinning tops tend to have a zip that doesn't go all the way down, like a two-thirds zip, and they have kangaroo pockets inside. When you rip your skins off your skis and you're transitioning from an uphill to downhill, you just fold up your skins or shove them in your top. But the tops are also quite good for shoving water bottles in and food. So I guess that's maybe why a lot of the lightweight backpacks that have been designed for the sport don't have as many pockets. You have stuff on your skin suits and the clothing that you’re wearing for extra little bits, but it's not particularly organised and it's easy for stuff to drop out, not always proper pockets and stuff like that."

What other strategies have you tried (or seen other athletes try) in terms of carrying things?

"Aside from the running vest idea that I’ve been trialling, a lot of people have water bottle holders with insulated water bottles, like hard flasks rather than soft flasks on their shoulder straps. I just think it feels a bit old school and it's quite bulky and doesn't really work for me. On the specific backpacks, they have a little area but that’s where you would tend to put your crampons or jacket. It’s pretty easily accessible, so you can just throw it in there and pull it out."

As with other endurance sports, you’re out there for a long time. Since these races are in the mountains, what conditions do you expect to cover in just one race?

"It’s always dependent on the weather conditions on the day, but for this upcoming race we're starting at midnight and climbing up to about ~3500 thousand metres (~11483 feet). We’ll reach this at around three or four in the morning, and with a bit of wind, it’ll be well into the negatives, maybe minus 10 degrees Celsius (14° F). And then on some of the final climbs it might feel like 15 degrees Celsius (59° F) with the sun reflecting back off the snow. Because of all your ski gear, I've definitely found last time we did this race on some of the final boot packs and climbs, you're really hot and really sweating!"

Considering the elevation you mentioned, do you incorporate altitude training?

"I've been lucky with this season, as I've been to altitude quite a lot. I think for this race it does make a difference because, like I said, the first skin goes up to ~3500 metres (~11483 feet). So at the top end of that, and honestly as soon as you start getting over 3000 metres (~9843 feet) anyway, there's definitely some gains to be had if you're well acclimatised. Then you tip over 3000 metres a few times after that during the race. I've not put a specific emphasis on altitude training this season just because I've naturally been to altitude quite a lot through work, trips, trailing, etc. And for these kinds of races, it definitely makes a difference."

How do you navigate a race starting at midnight between fueling, hydrating and trying to sleep?

"I tend to have a late lunch around 3pm and then try to sleep before having a smaller dinner around 9pm. That's when I typically get in a decent bit of hydration as well. I’ll have another snack half an hour before starting the race. I try to almost reset my body clock a little bit. When an event goes through the night, I’ll try to have some kind of solid food around breakfast time, maybe 6 or 6:30am. This way I can feel a little bit satisfied from a mental point of view that I've had some ‘real food’, since it feels like my breakfast time. So overall, I just kind of reset a little bit, have a big feeding early afternoon, sleep, smaller feeding and then a snack. It’s definitely not solid sleep though, but still eyes closed, lying down, resting."

In the prep for the Patrouille des Glaciers, Sam undertook the Grand Traverse, point-to-point ski race from Crested Butte to Aspen, which helped fine-tune the strategy based on what did and didn't work.

What did you learn from this prep race in Colorado going into your A-race?

"My partner and I took the skiing pretty cautiously in Colorado, but even operating at a slightly lower intensity, I definitely found it pretty hard to fuel as much as I would do when I'm running. I was pretty on the dehydrated end of the spectrum but really didn't feel the need to drink like I normally do during running. And with running, it's so easy just to dip your soft flask into a stream and get some water or you’re going past the aid station and you just pull your flask out. But there wasn't that ability during that race, since there were basically no aid stations.

"I took some salt capsules with me but I didn't use a single one. I had them in a little Ziploc baggie, but they were just kind of buried around the back of my race vest and too small to deal with when I had my gloves on."

For Switzerland, one of the changes we made was to mix his electrolytes into his fluid (including using Carb & Electrolyte Drink Mix and then PH 1500 (Drink Mix) packets) to make sure he was consuming adequate sodium, especially as a fairly salty sweater. We also switched to PF 90 Gels since they’d be easier to handle with gloves and could deliver larger carb doses.

Unfortunately, due to weather conditions, Sam’s race was cancelled last minute. But based on our strategy chats ahead of time, here’s the menu Sam was planning to follow:

  • Start with 2 x 500ml bottles, each with 2 scoops of Carb & Electrolyte Drink Mix and 1 x PH 500 tablet

    • Drink whenever possible
    • 1L fluid, 1500mg sodium, 60g carb

  • Refill bottles with water and 1 x PH 1500 packet at aid stations

    • Drink whenever possible
    • 1L fluid, 1500mg sodium, 30g carb

  • Carry PF 90 Gels and PF 30 Chews

    • Consume ~2/3 of a PF 90 every hour on uphill sections
    • Intersperse chews (2 packs per hour) if flavour fatigue hits
    • 60g semi-solid and solid carb per hour

Further reading