HOW THE BODY LOSES HEAT
The body loses heat in several ways, and the four elements of “COLD” address these areas in their own way. The four main mechanisms of heat loss are—
Evaporation. The body’s way of reducing its internal temperature is to perspire. Sweat glands take water from the blood to produce the sweat. At the same time, it moves the heat of the blood to the surface of the skin, where it evaporates, reducing body heat in two ways. The first method is by reducing the amount of heat in the blood, and the second method is by cooling the skin through evaporation.
Radiation. Because nature always tries to create a balance, if body temperature is higher than the air around it, the body will radiate its heat into the air. The greater the difference between body temperature and air temperature, the more heat is lost to the air.
Conduction. Heat moves from a hotter area to a colder area, and it moves through whatever is there to serve as a conductor. Air is the poorest conductor, because it isn’t very dense. Solids such as rock or dirt are the best conductors, because they are very dense and homogeneous. Water or moisture are moderate-level conductors but are the most common when outdoors. Keeping your body and clothing dry will help inhibit this movement of heat out of your body.
Convection. Your body heats the air around it through conduction, as described above. But if that warm air is pushed away from your body by a breeze or other action, your body will heat it again and again, until whatever is moving it away from the body stops. The loss of heat by moving the warm air is called “convection.” A common example of this is wind blowing across your body. This cooling of the body is called “wind chill.”