Sweat, the body’s air conditioner that dissipates excess heat from within and prevents your brain from burning up. Humans can tolerate body temperatures 20 degrees below normal for long stretches of time, however 6 degrees above normal the brain starts to malfunction, and at 12 degrees above normal stops working altogether.
There are two different types of sweat produced by two different types of glands. The first type eccrine gland is dispersed over the body’s surface. Its function is temperature regulation, it the type of sweat we associate with humidity and exertion. Its texture is more like water and evaporates directly off the skin.
The second type is nervous perspiration and is generated by stressful situations. It is secreted by the apocrine glands, which are located in the armpits, genitals, palms of hand and soles of feet. The apocrine glands empty into the hair follicles and mixes with oil and dirt. It is the sweat that smells and stains clothing. Obesity causes a person to sweat more because the more weight that is carried the more the metabolic heat one needs to eliminate.
Low-sweaters have an advantage in athletic performance because they have to rehydrate less. Very fit people have less salt in there sweat and retain more of it which is important because sodium chloride is important in maintaining fluid volume.