Heat Index Hot conditions put your body under a lot of stress. Physical activity stresses the body even more. When heat is combined with physical activity, loss of fluids, fatigue, and other conditions can lead to a number of heat-related illnesses and injuries.
Death is even possible.
Heat stress is commonly associated with warm weather. It is true that warm weather increases the number of heat-stress injuries and illnesses. Warm weather is not the only cause of heat stress, though. Heat stress can occur any time the surrounding temperature is elevated. Even if the weather is cool, you may work in warm areas, indoors or out.