Sweat is what cools us. No sweat, no cooling. When you get so dehydrated that you're getting close to heat stroke, you stop sweating. That doesn't seem like the smartest thing for your body to do, but that's what it does. So I watch my forearms. Dry forearms means I'm in deep doo-doo. Not good, need shade and water NOW. That's the only issue I have with wearing sun sleeves. Before I get dry forearms, I've also stopped peeing. No pee, need water.
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Results matter