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How cold is too cold to run outside


By Henry Howard


This past week I hit my limit of how cold is too cold to run outside. On Wednesday morning, the real feel temperatures was minus 12 Fahrenheit.


No thanks.


Wednesdays are typically my second-hardest workout of the week, balancing my weekend long run. Due to the bitter cold, I switched around my schedule: did a core workout early Wednesday, and switched my Thursday run to late Wednesday afternoon. That allowed me to move the Wednesday run to zero dark thirty Thursday morning when it would be safer due to less traffic.


I had been consistently running in single-digit temps, often hitting zero or a few degrees below. But that minus 12 was a non-starter for me, especially on a day when I was planning a quality workout.


That range comes close to recommendations from the American College of Sports Medicine (ACSM). They recommend not exercising outside when the temperature hits negative 18 degrees, when the risk of frostbite increases.


Even before frostbite begins outdoor adventurers could be susceptible to cold stress. That occurs when the body is unable to warm itself, which may bring on serious cold-related illnesses and injuries, permanent tissue damage or even death.


Four factors contribute to cold stress: cold temperatures, brisk or cold wind, dampness and cold water. When it’s cold, the body must work harder to maintain its core temperature. While below freezing conditions combined with inadequate clothing could bring about cold stress, it can occur when temperatures are in the 50s with rain and/or wind.


If you do suffer from cold stress, here are some treatments via ACSM:

  • Move to a warm environment.

  • Remove cold and wet cloths.

  • Find access to warm air, such as heaters or fireplace.

  • Use electric or non-electric blankets.

  • Drink warm beverages.

Tips to stay safe

Runners have their own thresholds of what temperatures they consider too cold. No matter your limit, be safe when heading outside when the temperatures are unforgiving.


I offered some tips in an earlier post about how to run safely in winter. Here are some more that are specific to bitter cold temperatures:


Wear the proper gear: Bundle up in layers to protect your skin, especially the extremities, from the cold. When it’s in the single digits, I am typically doubling up gloves and socks. I also swear by gear from Odlo, including this amazing jacket that accompanies me on nearly all of my winter runs. For more than 70 years, European-based Odlo has been keeping runners outfitted in proper gear that is lightweight, comfortable and easy to clean.


Monitor your breath: Cold air can wick away precious moisture in your mucosal lining, leading to respiratory problems. Try to avoid mouth-breathing while running in cold, dry air. Wearing a mask helps and breathing through your nose are recommended.


Protect your phone, too: Whenever we venture out into the mountains or trails, our phone is our lifeline. The risk of an emergency is elevated when the temperatures plummet. Protect your phone’s battery so you can use it to summon help, just in case. I recently tried and was impressed with this Cold Case that is meant for runners, skiers, hikers and others.


Warm back up: Immediately after your run in the cold, take a hot shower or put on warm, dry clothes. Grab a coffee or other hot beverage.


Stay safe and warm, runner friends. Spring is coming.





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