Originally Posted by TrojanHorse

I read an article yesterday that said hyperthermia removes your DESIRE to exercise... so it's a sort of mental thing. I think its when your core temperature hits 103 or something. Acclimatizing yourself helps maintain your core lower, proper hydration as well, but I was a little surprised by the conclusion that you don't lack the strength to continue, it's the willpower. I don't think they were suggesting a dose of HTFU or anything, more of an awareness so you can manage your temperature. I had to take a short break in the shade on Saturday when I went out too, I was riding in the 90s in direct sun for 5 hours. Hawt.

You also lose 50% of your body heat through your head, so maybe there is something to be said for pouring water on your head when it's hot.