RebeccaSweatology

Sweatology Notes
 * Excretory System (Skin, Sweating)
 * Body Temperature Regulation (Nervous and Endocrine System)
 * Circulatory System (Heart and Blood Vessels)
 * Medical Consequences of Heat Stress
 * Water
 * Salt

Sweat is our interior coolant, part of a uniquely human biologic machine. Humans have internal temperatures. Humans can tolerate overcooling, routinely recovering from long periods of hypothermia with body temperatures diving 20 or more degrees below normal. Humans can not tolerate overheating as much. The brain malfunctions with six or seven degrees of fever and an internal temperature of 110. We have to have a good internal air- conditioner to be able to survive to dissipate the heat and to relieve the heat that is generated by our bodies metabolism.

Without sweat glands keeping us cool with copious sweat we would still be clad in the think hair of our ancestors living like apes. Sweat glands evolved as body hair vanished allowing optimal cooling of the enlarging hominid brain and an active lifestyle even in the blazing sun.

Humidity reduces evaporation and makes everyone sweatier. A breeze enhances evaporation and makes skin cooler. Dehydration markedly reduces sweat production. So does sunburn.

Some people have more than 2 million sweat glands, some have as many as 4 million sweat glands. Heavy sweaters may have sweat glands that are more than 5 times the average size- they make more sweat.

After you are 60, you sweat less- at a higher risk for a heat stroke. Over weight people have trouble getting rid of all the heat in their body.

When you sweat you lose you water in your body, and you need to drink water to replace all the water that was loss when you sweated.

When you sweat you lose the salt in you body.