Staying warm while downhill, Nordic, or backcountry skiing, snowshoeing, or hiking in winter is a constant challenge: We sweat, our clothes get damp, we have periods of reduced exertion like riding a ski lift or walking downhill, and then we get cold. But as humans have known for thousands of years, it’s a matter of smartly managing and insulating our body’s furnace (and today we have much better technical clothing than animal skins).
Clothing only helps trap heat; your body is what keeps you warm. Anytime you get cold, the single best strategy for rewarming is to start moving or increase your pace. Watch others in your group for signs that they’re cold, especially children, who have less body fat and mass and cool off more quickly than adults. When you take a break, make it short, to avoid cooling off. If someone has visibly cooled off faster than others during a break, have that person start moving ahead of the group; you will regroup before long.
2. Pace Yourself
Minimizing how much you perspire in cold temperatures is critical to keeping warm, because wet clothing conducts heat away from your body. Try to set a pace that keeps you warm without causing you to overheat and perspire heavily. I try to strike a balance between producing enough heat to keep my toes and fingers warm without sweating copiously in my core; generally, that pace has me breathing heavily but not panting.
3. Adjust Layers
Sometimes, whether climbing uphill on backcountry skis or snowshoes or in high-exertion activities like running or Nordic skiing, it’s impossible to avoid sweating, so adjust your clothing layers. For example, if there’s no wind and you’re exerting hard, you may only need a breathable insulation layer (like fleece) over a fast-drying, wicking base layer. If it’s windy, you may want a waterproof-breathable hard shell over a midweight insulation layer, like a fleece or a vest, to prevent you from cooling down.
4. Eat More
Your body needs more fuel in freezing temperatures to keep your internal furnace burning. Eat high-fat snacks like chocolate, cheese, and nuts, because fat is a slow-burning fuel that keeps your body going for the long haul, which becomes even more important in the cold. Keep snacks handy so you can refuel frequently; feeling a chill or fatigue is often an indicator that your body needs food. If you eat energy bars for convenience (especially when wearing gloves), choose ones that pack plenty of protein and calories.
5. Drink Up
In cold, dry conditions typical of winter, you become dehydrated more quickly than you realize, even if you’re not sweating much. Drink frequently. Carry a thermos with a hot drink. Add sugar to it (for quick energy) or a little dollop of butter for flavor and fat.
6. Pre-Warm Your Gloves And Boots
Pre-warm your gloves and boots by a heater before going outside, so your fingers and toes feel toasty the instant you put them on. Fingers and toes get cold most easily because they are the parts of your body farthest from your heart; and because, once they are cold, your brain directs the capillaries in your extremities to cut off circulation to those parts (known as vaso-constriction), to protect the body’s core from cold blood returning to the heart.
7. Dress Like A Goose
If you stop for more than a few minutes, put on a fat down or synthetic-insulation jacket immediately, to prevent your body from rapidly cooling off. Take it off right before you start moving again, so you don’t overheat.
8. Worship The Sun
Just as you would seek shade when taking a break on a hot day, in cold temperatures, take rest stops in warm sunshine, and face into the sun. Ideally, find a spot that’s sheltered from the wind, or put your back to the wind. Keep in mind when planning trips in advance, especially when taking out people new to winter outdoor activities, that you can improve the chances of them enjoying it by taking them out in March or early spring, when the sun is much higher and warmer and days are longer than in December or January.