I'm a wimp when it comes to riding in the heat....partly because I don't sweat much so when I get overheated, I actually get the chills and goosebumps. I've gotten sick from working out too hard in the heat, so I know the warning signs for myself and take necessary precautions.
The best preparation for me is to remember hydration begins BEFORE the ride - I make sure that I'm hydrated well everyday and I drink a 20 oz bottle 1/2 hour before my butt hits the saddle. Just as Incommunicado suggested, I drink at least 8-20 oz per hour.
In another topic on this board these suggestions were given: bring a camelback, douse your head/body during the ride to help cool down, use water soaked cooling bandanas around your neck, and freezing half filled water bottles - then topping off with water before a ride so the water stay cool during the ride. **I also use those frozen bottles to place on my neck for instant cooling.
Good luck staying cool this summer!
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