Water Hydration - Temperature Regulation When we get too hot, we make sweat. Without enough water in our diet, we can’t make enough sweat. Temperature regulation, and prevention of over heating, can be accomplished by drinking adequate water. The more you sweat, the more you need. If you weight yourself prior to exercise, or gardening on a hot day, and weigh yourself after you can determine how much water you lost by sweating. Each pound lost is about 500mL of water that needs replacing.