Hypo-thermic training (Winter endurance)

Hey crew,
There has been a fair bit of talk on the podcast about hyperthermic training and heat adaptation. Personally, it doesn’t get terribly hot here in Northern Minnesota, and my A race for the year is an ultra-endurance fat bike race in January. Temperatures average -20F, and can be much colder at night depending on the weather. I know from experience that the real trouble is avoiding sweating. In winter expeditions there is a mantra of “you sweat, you die”. Learning to shed layers accordingly is one thing, but are there any physiological elements or considerations to avoid sweating or train the ability to run cooler?

Curious to hear those with knowledge or experience on this. Cheers!

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Not that I’ve heard of. Possible fat vs glycogen create different amounts of waste heat, but I’ve not seen anything on that.

I think it comes down to appropriate pacing and layering/de-layering like you say.

You can also try vapor barrier liners, but takes a bit of practice to get right. I’ve used them on my feet with reasonable success.

Coming from Finland I can relate to this. One quick fix is to wear clothes that remove sweat from the skin or stay warm even when wet. Merino wool products are undoubtedly best at this. I’d steer away from products that aren’t 100% wool. Also have middle layer made of fleece or similar and wear a windproof jacket on top that has ventilation. Changing what you wear on your head makes a big difference as big portion of the cooling comes from your head. You could also just ride slower :stuck_out_tongue_closed_eyes:


The holy Scandinavian trinity :100:


As a Scotsman living in Finland I had to learn to adapt my winter wear from wet and windy to dry and cold. I tend to feel a bit cold on the warm up and normally need to drop a layer after about 10mins.
Still not got it dialed, -2°c with wind can feel colder than -15°c. And when it’s -25°c and below you soon know if you’ve messed up your layers :dizzy_face:

Fat bike ultra in January - Arrowhead 135?

I raced the Tuscobia 80 last year and am signed up for the Tuscobia 160 this year so here are my race notes from last year (temps 0-15F, wind out of the southwest @ 8-12MPH for last few hours of my race)

Merino base layer socks (REI brand I think)
Ziplock 2 Gall on bag with the zipper portion removed as a vaper barrier. Worked like a charm - there was moisture in the bag at the end but my feet were toasty the entire race.
Wool socks
45Nrth Wolvhammr boots. I’ve worn these down to -12F with no issues.

Craft ltwt thermal pant
45Nrth pants (naughtvind I think). These were great with the pockets and vents; however, even with every vent and pocket unzipped the base layer was a tad damp at the end. Nothing that seemed to cause me any issues but just worth noting. There are zippers at the lower leg for get the pants down over the boats and I would leave that unzipped this year (provided temps are the same).
Pearl Izumi bib (switching to Pactimo 12 hour bibs this year).

Upper body (daytime)
Craft ltwt short sleeve thermal T
Merino wool jersery
Merino wool arm warmers (outside of jersey for ease of removal if needed)
Wind vest (wind block in front, mesh in back for breathability).
Ltwt fleece glove (used Revelate Designs Pogies without the fleece liner).
Merino Wool buff (loved this)
Headsweats helmet liner.
For this temp range this setup was absolutely perfect - didn’t sweat and didn’t feel cold.

Upper (after dark)
Craft ltwt long sleeve thermal T
Merino Jersey / arm warmers
Wool Buff
OR Insulate vest - put this on for the last 16 miles. Did I need to change out the other vest - not sure but it gave me an excuse to stop and eat. It worked out Ok but it’ll get changed out for a down vest this year.
Same gloves.
Fleece ear warmer - pulled this down to cover my face (nose and ears). Worked great.

The after-dark gear has been tried out down to -12 or so and I can ride with just that for a quite a while. I’ve steered clear of the full jacket and stuck with the vest as I’ve yet to find one that dumps enough heat and doesn’t induce sweating. No matter what Gore-Tex says - it can’t transfer that much moisture IMO.

For me it all comes down being comfortable being cold for long stretches. I’m ok with it and I like it. I’m guessing if you are from MN then you are ok with it as well. Hope this wasn’t to far off track for you.

Now a question for you - how are you managing TR for a race that can take some people 30hrs to finish? I’m struggling with how to use TR for events that are longer than I think they planned for.

I think no matter your riding discipline, higher FTP - via higher VO2max and higher % you can sustain for long periods - is helpful.

For really long stuff, there’s no substitute to time in the saddle - both for fitness reasons (training your body to burn fat at endurance pace), to get used to long hours on the bike, and to dial in your equipment (really important for riding in the cold).

Yup. AH135 debut (assuming I get in on Sunday!) And Tuscobia 80 as a primer.

Sounds about as expected, I’ve had similar setups on rides including overnight -20F last year (we did a “Spirit of Arrowhead” night ride on race day).

Was hoping for tricks to avoid sweating, but no magic pill I guess. Alas.

As for TR training. In Sweet Spot Base 2 right now, doing Heck of the North, then Sweet Spot Build, and Century specialty. Like others said, FTP gains mostly. I’ll likely work in 4+ hour outdoor rides as it cools down further and further. Right now I’m Mid Volume and adding commuting and running on top, but by winter will be overshooting the long ride hours as outside rides a fair bit and adding more XC skiing too.

I’ve been riding the fat bike in ultra gravel races, 5 days with over 8 hours so far, but my setup will evolve as snow comes in. I rode basically my winter setup for Lutsen 99er.

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I hope you just mean the bike setup!! It was hot this year.

I have no specific recommendations for you as I’m a little shy to do the events where screwing up could mean loss of body parts or death. I had a buddy who spent the better part of a year recovering from frost bite on his foot from AH135 in 2018. I’ll stick to racing around in my spandex in the winter (nordic skier).

I would talk to as many folks as you can about their setups. What I gather is there are a few different basic strategies and then a whole bunch of different gear and execution choices. But it all seems to boil down to sweat as you are well aware.

Best of luck! I’ll try to remember to look for your name on the tracking spreadsheet for Tuscobia and dot on AH as I’ve got friends doing both again.

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For feet in winter use potato chip or crisp bags with the silver lining on the inside. They will reflect heat back at your feet.

That’s -28C!!! :cold_face: :snowman_with_snow:
And I thought I was tough cresting a hill and it dropped to -2C, briefly.

Its the humidity that makes the difference. Rain and -2C can feel colder than dry -20C. Which is why the above discussion is so focussed on avoiding sweat.

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I will also be doing Tuscobia 80 and Arrowhead this winter! Hope to see you at the starts (and finishes!).

Not sure if it helped at all, but last winter I did all my TR workouts in a cold basement with a fan in a tank top. Being able to tolerate that little bit of cold before you warm up helps minimize sweating and stopping to take layers off.

Any recommendations on glasses/goggles? Mine always fog and having my eyelashes freeze together gets annoying. I’ve been looking at fur ruffs, but they’re spendy.


I haven’t quite figured out the glasses etc yet myself… I am a prescription glasses wearer myself, so when no goggles no fogging issues since they aren’t so tight to my face. I had good luck at -20 in the BWCA skiing last year with “Face Tape” and normal glasses. Also have had OTG goggles work out OK.

Further development and testing needed! I hope to try out a Cold Avenger mask or similar as well.

I ride all winter in Montreal. I echo prior comments on Merino but I think your main challenge is dressing to your expected pace. You will be producing a good deal of heat just from aerobic activity, exactly how much is a function of your race pace. The trick is to really feel the cold when you start out such that when you reach “race pace operating temperature” you are comfortable and not sweating. The related trick is to know exactly how long it takes you to reach “operating temperature” so that you don’t hesitate to make adjustments before they are needed. Finally if you need to stop along the way, you will cool quickly - bring a light down jacket to use for stops.

Another tip is to think of your hands as radiators. I often ride with liner gloves inside my regular gloves. If I get warm I drop down to just the liners, its amazing how quickly that cools me down.

With regards to glasses, I’ve tried all sorts of things but the simple truth is below -10c biking without goggles is unpleasant and below -20c biking with goggles over glasses is going to get foggy. So, below -20c I use contact lenses.

Good luck!

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This really warms my heart to see that I’m not the only one on the forums that loves racing in obscenely cold weather - my friends and family think I’m crazy.

Looking forward to circling back to this thread in 2020 to see how things went.

I ride in the cold, but have not done any races - you guys are nuts spending days out in the snow!

Some friends of mind rode the ITI 350 this year, and are signed up for ITI 1000 next year. That’s some serious commitment to spending time in the cold.


The ITI 350 is on the bucket list but I have a better chance of getting out to JayP’s Fat Pursuit. I’ve heard rumors that there may be a 350 miler coming to northern MN (same trail as the Beargrease sled dog race). Would be nice to have a multi-day event that close to home (metro-Detroit area).

JayP rode the Beargrease Sled Dog course last year (along with Ben Weaver) and rumor had it that he was scouting it for a race route, but there but there are also other local RDs to factor for a similar route. Perhaps a “race” to get that race route established.

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My friends did the Fat Pursuit as a “qualifier” for ITI. In some recent years, the Fat Pursuit 200 has been more demanding than the ITI 350. Good training ground for the ITI.