They feel like painful muscle spasms, usually in the stomach and legs. If you should experience these, rest in a cool place and drink cool water or a sports drink. Salt tablets can make the situation worse, so do not take them. Heat exhaustion is more severe than heat cramps and has several symptoms. They include weakness, nausea, exhaustion, headache, dizziness, cool, moist, pale or flushed skin.
Heat stroke is the most severe heat related illness.
It usually occurs when someone ignores the symptoms of heat exhaustion. It is a serious medical condition with symptoms such as red, hot, dry skin, changes in consciousness, rapid, weak pulse and rapid, shallow breathing. When it occurs, emergency medical responders should be called immediately. Light colored clothing reflects away some of the heat. Drink water, even if you do not feel thirsty.