It's not just the wrists, it's the pulse points.. all of them, and it works. Coldness/coolness, whether it be ice or cool compresses on wrists, behind the knees (really) behind and around the head. Wet down your hair. Sit in a tub. Heat stroke/exhaustion is very serious and can be deadly. Extra salt and more water intake than you think you want. If you start to get nausiated get to a medical facility quickly. No joke.