How a Body Overheats
Tuesday Jul 14th, 2020
During exertion the body produces heat. To lose excess heat, the body uses a combination of radiation (loss of heat), convection (cooler air movement), conduction (contact with cooler surfaces), and evaporation (sweating). If surroundings are hotter than the body, it is limited to shedding excess heat by evaporation of sweat alone.
Unfortunately, copious sweating places a heavy load on circulation, which is needed to bring blood to the skin for cooling. As the body progressively dehydrates through sweating, circulation is compromised and heat storage begins to exceed heat removal. This further increases the strain on the circulatory system in a vicious cycle. The strain increases heart rate, sweat rate, and core and skin temperatures. Eventually the strain can cause heat stroke if the body is not cooled by some other means than sweat.
Solutions are to drink small glasses of water every 15 to 20 minutes, remove yourself from the sun for at least 5 minutes while drinking water, avoid caffeine which causes your body to lose water, and avoid working outside at the hottest times of the day. The more you do to bring your body temperature down, the more you can reestablish equilibrium between heat storage and heat removal.