Heat-related illnesses include dehydration (deficit in body fluids), heat exhaustion (nausea, dizziness, weakness, headache, pale and moist skin, heavy perspiration, normal or low body temperature, weak pulse, dilated pupils, disorientation, and fainting spells), and heat stroke (headache, dizziness, confusion, and hot dry skin; possibley leading to vascular collapse, coma, and death).
Heat injuries are always dangerous and can be fatal. Heat-related injuries are a particular problem for children because children perspire less than adults and require a higher core body temperature to trigger sweating.
Playing rigorous sports in the heat requires close monitoring of both body and weather conditions. Fortunately, heat-related illnesses can be prevented.