High-output, low temps:
Layering for intense cardio when it’s cold

Recently we posted an overview of typical layering system definitions, especially as they relate to winter sports. But it’s also worth sharing a special highlight of layering for “high-output” activities like ski touring and ski mountaineering. These sports are trickier to get just right—your heart rate is often roaring fast enough to keep your body toasty, even if it’s really cold out. But the moment you stop for a break, a belay, or a transition, your body’s furnace stops—putting it at risk of a deep chill.

If you don’t layer right, sweat can become your biggest enemy. If you’re too hot on the uphill—especially if you’re hot and wearing a layer that holds perspiration in so you start to get soaked—that wetness will feel absolutely freezing the moment you stop moving. When you’re in cold winter temps, especially high in the alpine, that chill gets downright dangerous fast. And there’s no way to quickly dry off and stop the chilling, other than stripping all your layers off and starting over with all-dry ones. (Not a pleasant or realistic feat on a mountaintop.)

Stop vs. go. 

Many seasoned alpinists recommend a solution that breaks away from the typical baselayer/midlayer/shell mindset and instead embraces an “action suit” system. (To be fair, “action suit” does indeed sound cooler than “baselayer/midlayer.”) This system has you layering for two modes: moving and stopping.

When you’re moving, you’re probably hot and need very few layers—and the ones you do wear need to be very air-permeable so sweat can evaporate out. When you’re stopped, you’re going to get cold quick, so you need to immediately add insulation on top to trap your heat while you have it.

How this looks in action:

On your ascents, layer more minimally than you think you need to. On a cool winter day, may only need a base layer shirt, a light beanie or ballcap, and light glove liners on your hands. If it’s very cold, you might add a breathable vest or light breathable softshell or windshell. If the cold is extreme, maybe you go with a heavier softshell. But whatever the temps, everything you wear on your ascent should be as permeable as possible—meaning your sweat won’t accumulate on your body or saturate your clothes. It will evaporate away so you can stay as dry as possible.

A waterproof shell jacket usually does not make sense for ascents, unless it’s pouring rain or dumping snow. And if you must wear one for these conditions, make it as light and breathable a shell as possible. If it’s only lightly drizzling or snowing, you may get away with a softshell for weather protection.

If you get to the top of the mountain (or the top of your tour, or just your next transition or belay) feeling dry, you’re winning!

As soon as you stop moving, you need to capture the heat you’ve generated on your ascent. Many people delay doing this, but by waiting till they feel cold before they throw on a puffy, they’ve already lost precious heat and subjected their core to cooling.

When you stop, simply put a puffy on over what you were wearing on your ascent. Keep the puffy easily accessible, just inside your backpack’s zipper. This is a fast and low-fumble way to capture your warmth. (In wet weather, you’re probably wearing a hardshell, which you’ll need to pull off quickly to throw your insulation under it, then suit back up with the weather-protective shell.)

Once your break or belay is over and it’s time to get moving again, get your furnace restarted while your puffy is still on. Maybe you skin for a minute, do a few hops, or shimmy a warming dance. As soon as you start to feel warm, peel that puffy off, stash it for your next break, and resume moving before you feel cool.

It’s all about preservation. 

This method boils down to “Add warmth before you feel cold, and ditch the warmth before you feel hot.” Stay dry on the up, and capture your heat before you lose it. This system can add tons of comfort on days with lots of starts and stops, and it’s an all-out life-saver in the alpine.

You can find every kind of layer under the sun here on Geartrade, UnNew and ready to accompany you on adventures.

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Beth Lopez is a seasoned writer and creative director who loves to tell tales of adventure and discovery—and finds writing a powerful way to give a voice to people, causes, and places. Beth runs amok in the Wasatch mountains when untethered from her computer. She believes there’s no such thing as a bad ski day and considers animals her favorite people. Don’t tell her mother about her Instagram mountaineering photos.