With the right gear, humans can run safely in temps down to -20 degrees Fahrenheit. I know, shocking.
I’m not suggesting that you want to (or should) do that though. I absolutely love to run in the winter but even I find that my comfort cutoff is well above 20 below, mostly due to the limitations of the gear I own. There’s also the fact that I usually have other options when the temps dip way low — like simply waiting a few hours to see if it warms up a bit or hitting the treadmill.
As intimidating as it might be to run in the cold, the most common problem with winter running is actually over-dressing, probably because we’re all afraid of freezing to death, which is a totally valid fear because there are very real dangers involved with working up a sweat while braving the cold. However, most of us go a little too far by dressing for the temperature we feel as soon as we walk out the front door. So, here’s what you need to know to run safely in cold weather.
What to Wear
A good rule of thumb to avoid over-dressing is to dress the way you would if you were not running and in temps that are 10-20 degrees higher (use the lower end of that range if your run is at an easy pace, shorter, or if you always tend to be cold). For example, if the temperature outside is 50 degrees, you should dress like you would on a 60-70 degree non-running day. Make sense?
Or just forget all the math and let me provide my personal cheat sheet.
For temps in the 40s: A long-sleeved moisture-wicking (absolutely no cotton) shirt and capris or long tights will do the trick. For the low 40s, you might also opt for a vest and light gloves.
For temps in the 30s: Go with a long-sleeved moisture-wicking shirt under an insulated half-zip pullover or jacket, long tights, warm gloves and a headband to cover your ears.
For temps in the 20s: Choose a long-sleeved moisture-wicking shirt under a mid-weight insulated layer and a jacket, cold-weather tights (or layer two thinner pairs), warm gloves or mittens (possibly two layers) and a hat. Also, consider wearing thicker cold-weather running socks or layering a thin pair under a regular mid-weight pair.
For temps below 20 degrees: Unless you’ve got specialized equipment, consider skipping or delaying the run. Without something covering your face and warming the air that you’re breathing before it hits your lungs, breathing becomes difficult and the cold temps can burn. This can leave your lungs feeling it for hours after your run is over.
Other Safety Considerations
Wind and wind-chill factor: The cheat sheet above doesn’t take wind into consideration. For windy days, I recommend a wind-resistant jacket on top of your warmth gear. This will help keep the wind from reaching the wet, sweat-covered layers underneath, which would otherwise make you much colder.
Reflectivity: As the days get shorter, be sure that you wear reflective gear or illumination if you’ll be spending any of your run outdoors before dawn or at dusk. Most running gear has some reflectivity to it, but having more doesn’t hurt. Blinky lights that clip onto your clothes and headlamps are also great options. You want the cars to see you from a distance but also ensure that you have adequate light to see the surface you’re running on to avoid falling or twisting an ankle.
Time of day: If you’re a morning runner, temps will most likely rise during your run. Conversely, in the evenings, the temps will fall during your run. Factor that into your choice of layers.
Do you run year-round or hibernate over the winter? —Alison