Running in the heat—it’s all about adaptation
As runners, we puzzle non-runners. They wonder, “Why do they run?” Or “That looks painful.” Or “Yuck, they’re all sweaty and hot.”
Yup, that’s us.
Non-runners might never know the answers to some of these questions, but the matter of sweaty and hot isn’t too much of a mystery. The secret: runners acclimate to the heat and over time, it’s not as miserable as it looks.
Adapting to the heat is a bargain because it produces predictable results in a relatively short time. Most runners can adapt to heat after exposure to hot, humid continuous temps through moderate running in 7 – 14 days. It takes a lot longer to see the effects of speed training, strength training and increased mileage.
The two keys to adapting to heat are blood and sweat. When our bodies re-learn to perspire efficiently, we increase the ability to regulate the core temperature around the vital organs (the blood) and gain more external comfort on the skin (the sweat) as well.
One of the chief adaptations the body makes to heat is increasing our blood volume. When we’re not heated from intense activity, there is plenty of blood to regulate internal temps and to cool the skin. But when we heat up, we call upon the vascular system to work harder to circulate more blood to produce sweat to cool the skin, to maintain the core temps, and to flow to muscles.
What happens in acclimating to heat? Our bodies get smarter and kick off the cooling process sooner, signaling us to start sweating sooner and distributing the sweat more abundantly before we overheat. What a deal!
Some of my best runs have been in high temperatures. Sure I’m a glistening ball of sweat careening down the street, but when my body has adapted, it’s not nearly the awful scene it appears to others.

Learning everyday..
My body is gonna go in overtime in August here. LOL!
Posted by: Viv | May 28, 2008 at 09:30 AM
I'm hoping my adaptation skills kick in soon because it's going to start getting toasty around here.
Posted by: Jess | May 28, 2008 at 01:22 PM
If you haven't seen it, you should go take a look at the excellent series about fatigue at the Science of Sport blog. They've been talking a lot about how temperature affects fatigue and performance. I thought it was fascinating.
http://scienceofsport.blogspot.com/
Posted by: Runatthemouth | May 28, 2008 at 02:20 PM
I think my body adapts by making me want to run on the dreadmill. LOL.
Wow. I learned something today. I am going to have to be a bit more persistent with the summer running.
Posted by: Nat | May 28, 2008 at 09:19 PM
My problem is that even in 30° F weather, wearing shorts, ss tech shirt under a light-weight sweatshirt, light gloves, and no hat, I still sweat buckets. When the temperature tops 80° ... well, it's not fun.
Posted by: Bob Allen | May 28, 2008 at 10:15 PM
Great post. I've found all of this to be true as well. I was thinking back to running in last summer's heat, and with a few exceptions (mostly caused by my not hydrating well enough), it just wasn't that bad. This definitely explains why.
Posted by: Betsy | May 29, 2008 at 10:48 AM
I love running in the hot weather as long as I'm hydrated properly and have Sharkies with me. I may have to slow down my pace a little if it is a really long run, other than that keep your fluids up and wear a hat!
Posted by: Laurel | June 01, 2008 at 06:02 AM
Tom, I had a BRUTAL run in the heat last night... and by run, I mean slow jog with multiple walk breaks. I came home and re-read this post, and it made me feel a lot better. I still need to get used to the heat, and when I do, it'll be easier.
Posted by: CoffeeBetsy | June 06, 2008 at 08:36 AM
This is the one we did, isn't it??? It's one of my all time favorite runs.
Posted by: coach outlet store | July 18, 2011 at 04:05 AM
I love running in the hot weather as long as I'm hydrated properly and have Sharkies with me. I may have to slow down my pace a little if it is a really long run, other than that keep your fluids up and wear a hat!
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