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  • Writer's picturecoachmk

WADOIDOO? Extreme Heat Edition

"Keep pushing, especially in environments that feel hotter than 104 degrees Fahrenheit, and  you put yourself at risk for more serious illness and injury." - Julien Periard

So, it's like REALLY hot.  #liberalconspiracy   Denver hit record highs last week; I saw 106 in my car thermometer three days in a row.  

The parents on this list know that 104 on an oral thermometer is the danger zone; that temp is well beyond the fever point that makes you FREAK OUT and take your kids directly to the ER.   Even if you don't have kids, you probably recognize that figure as dangerously hot.  Yet most of us aren't able to correlate inner (core) temps and environmental (outside) temps.   I don't want to bog you down with science and numbers much less overcomplicate your life.  I don't expect you to take your temperature on your runs (though it could be fun to take your temp at the end of your runs on really hot days).  I do expect you to check the weather forecast in advance and make good choices.  (spoiler alert: doing a temp run at 4pm on a 100+ degree day is NOT A GOOD CHOICE) All you need to know about heat it this:  1. it can be dangerous.  The danger point where I would cancel track workouts is 95 degrees.  Why?  the track reflects heat, it's usually 5-10 degrees hotter on the track.  Hot moving rubber striking hot stationery rubber can melt your shoes.   2. it will slow you down. Remember the 2016 Olympic Trials in LA when Shalane crossed the finish line then collapsed?  It was 78 degrees when the race ended, but humidity and lack of cloud cover brought real feel up to 88 degrees.  Then she had to go to Rio and race again under even worse conditions.  Sure, she's a pro.  But if the pros aren't impervious to heat then you can't expect to be, either.  Anything that slows them down a little will slow us down a LOT. 3. your core temps will be out of control long before you realize you are in trouble. The hypothalamus is responsible for maintaining homeostasis, but once your core temps hit 99.5, it is basically unable to do its job. Your body won't get this message for a little while longer, when you are in pain and in danger of dehydration.  All of the red flags swamp your brain and body simultaneously. 4. pushing through a hard workout on a super hot day is stupid.  90% of the water in your body is stored in your muscles, and when you are overheated you are draining those tanks, compromising performance.  Not to mention you have less fluid available to sweat and cool your skin.  So pushing in the heat makes no sense. We are here to build, not break. I live in Arizona.  116 is just June!  What's hot to you? Real feel of 104+ is dangerously hot.  Use an app like Accuweather to get Real Feel figures for your location.  That said, I try to avoid running in anything above 90 degrees as much as possible. I have little kids and cannot afford to come home totally wiped out or borderline dehydrated. But you chose to live in Arizona so clearly you have a death wish. #youdoyouboo So coach!  It's HOT by your pansy Northern standards and I can't run before 8am.  WADOIDOO???

  1. run in the evening after the sun sets. 

  2. if you can only run in the afternoon, run in a shaded area and take lots of water with you.

  3. if you can't run in a shaded area safely, consider taking it indoors to a treadmill. 

  4. if none of the above options are possible, your workout immediately converts to an easy effort (140 or less) run with accelerators at the end.  No pacework.  No speedwork.  Walking is fine. Time on your feet is all that matters.don't forget to wear sunscreen, and consider a visor.  Even though they are dorky they wont' trap heat on your head. 

  5. If you are bald or shave your head, wear a hat to reduce chances of sunburn.

  6. be aware- if you know the week ahead is going to be hot, dial in your nutrition.  Cut the salty and oily/fried foods that make you retain water and up your veggie and protein intake.  And drink lots of Nuun or Skratch to stay replenished in between runs. 

  7. follow up with a LUKEWARM, not cold, shower.  Your already-overstretched hypothalamus can send your overheated body into shock.

Um, Coach?  I'm a trail runner.  Are you still talking to me? Sadly, no.  Heat and sunlight reflect off of concrete, asphalt and rubber quite directly.  This doesn't happen on dirt so much. That said, any trail that is cleared, groomed, or safe from predators probably isn't well shaded so you need sunscreen, a hat, possibly a rash guard and definitely sunscreen.  Furthermore, most trail races start late and last all day long, so you need to get used to being in heat and direct sunlight.     You are coached.  You are loved.  You have to make good choices if you wanna stay alive to win at life, so let's do that okay? xoxo Coach MK "...Julien Periard, a physiologist at Aspetar who studies the mechanisms limiting prolonged exercise performance in heat. According to Periard, if your core reaches 99.5 degrees Fahrenheit (nearly a full degree above your baseline core temperature of 98.6), “the hypothalamus realizes it’s time to lose heat.” As a result, the brain reacts by opening up blood vessels near the skin and routing blood to the periphery, where it can cool.  If you continue to exercise in an environment that feels warmer than 99.5—from the air itself, but also humidity, wind, and sunlight—your body struggles to shed heat and the temperature of the blood entering your brain continues to rise. When this happens, according to Periard, neuromuscular fatigue increases: “You can’t contract your muscles with as much force as usual.” In other words, you slow down. “It’s the brain’s natural way of telling the body to stop generating so much heat,” says Periard. "

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