Heat Resistance

[shadowfoot]

It is starting to get hot where I live. It was over 80 degrees and humid today. In the summer it will get up to 90-100 for a few months. Seeing that it is the first day of being really hot, up from the 50s and 60s, and my body is used to producing a lot of heat for that and cold showers, I felt a little bit like I was trying to run through water on my run today. This appears to be the normal response among people. Everyone I know is moaning about how hot it is with the AC on.

And that brings me to my point of hormesis of heat resistance. See, last summer, and every summer before that, I have quickly adapted to the heat by spending a lot of time outside and never using the AC unless it gets really hot (so that my house is never cooler than 85). My body adapts to the point where I literally do not think it is hot until it is 100 and humid. I also tend to go for very long runs in the summer in the range of 90+ degrees for 10-20 miles, ah la Tarahumara.

To me, this is obviously hormesis. I cannot "just" do something, but with enough time for my body to adapt to it I can. I would be interested to see what you guys think of this particular example of hormesis. Have you noticed this yourself? Is it something you might like to try? And what I am really interested in, what do you think the body does that makes one tolerant to heat in terms of physiology?

-shadowfoot

[Todd Becker]

Shadowfoot,

Interesting topic here. This does seem like a good example of hormesis, although I'll have to research what physiological mechanisms might be involved.  The one observation I would add is that I've noticed that taking hot showers and drinking hot tea or other hot beverages in the summer has a noticeable cooling effect.  This might seem strange and unpleasant, but it actually works. I used to think this was paradoxical, but it totally fits with the opponent process theory. In a similar way, I've found that cold showers keep me warmer and immune to catching cold in the wintertime.

Your idea of taking long hot runs in the summer has some attraction, but just be careful to hydrate well.  We don't want you to get heat stroke or pass out from dehydration!

Todd

[shadowfoot]

Todd,

Don't worry about me. I learned my lesson about pushing myself too hard in the regard last summer when I did a twenty mile run without food or water in like 70 degrees. One's muscles and ability to move start to get interesting at that level of exhaustion and dehydration. So now bring water for longer runs in case I need it.

I am interested to try the hot showers that you suggested. I'm sure that acclimation to heat definitely involves partially shutting down thermogenesis. I come to this conclusion because while now (coming off of winter) 50 degrees is warm to me, in the summer once it drops down to 70 degrees it is cool and anything below that I start to get cold.

-shadowfoot