Fun Fact- Heating and Cooling the Inner Body

Marvelous things happen beneath the skin in the heat of the sweat bath. The capillaries dilate permitting increased flow of blood to the skin in an attempt to draw heat from the surface and disperse it inside the body. The bather's skin becomes cherry red. The heart is pressed into a faster pace to keep up with the additional demands for blood. Impurities in the liver, kidneys, stomach, muscles, brain, and most other organs are flushed out by the faster flow of juices. The skin and kidneys filter the wastes, excreting them in sweat and urine.

Some researchers claim that the rapid flexing of the heart and blood vessels in the heat of the sweat bath is a healthy exercise that puts little more strain on the heart than strolling on level ground. The increased capillary volume, they say, keeps blood pressure normal.

While the surface temperature of the skin may rise as much as 1O degrees C, inner temperature increases up to 3 degrees C. It is a common knowledge that many bacterial and viral agents do not survive well at temperatures higher than normal body temperature. It is also possible that damaged cells repair themselves quicker in fever conditions due to the increased metabolic rate. Recovery from illness then comes easier and quicker.

The inner temperature rise also affects the function of important endocrine glands, the pituitary in particular. Located in the bottom center of the brain, the pituitary is known as the master gland because its hormones regulate both metabolism and the activity of other glands such as the thyroid, adrenal, ovaries and testes. Urged by the heat, the pituitary accelerates the body's metabolism and affects the interplay of several of the body's hormones. Some people have gone as far to say that sex drive is increased and growth stimulated in the sauna bath.
The oxygen needs of the body increase by about 2O percent so the lungs, another important eliminator of body wastes, join in the body's quickened pace. Clogged respiratory passages are opened by heat, giving relief from colds and other minor respiratory problems. Sweat bathing is not recommended for those suffering from pneumonia or other acute respiratory diseases.

When the bocly is slowly cooled, the effects of heat are reversed--the heart calms, sweat pores close, dilated blood vessels contract and body temperature returns to normal. On the other hand, abrupt cooling brought on by a plunge into snow or icy water creates a more dramatic effect. For this reason, people with weak constitutions should avoid rapid cooling. Vessels near the skin's surface contract, but since the skin's metabolism returns to normal slower than the circulatory system, wastes accumulate that are normally washed out by the blood. Local vasodilators are then stimulated and blood rushes back to the skin's surface. The heart continues to beat vigorously and you may experience psychedelic flashes bouncing across your retina from the increased adrenal activity--an unforgettable experience! Goose bumps sometimes appear, a phenomenon reminiscent of the time when our prehistoric ancestors possessed a shaggy pelt of hair. Goose bumps extended the hair, making it thicker and giving more insulating power against cold or protection from attack. The swift transition from hot to cold stimulates the kidneys and usually creates the desire to urinate.

The typical body is 6O% water by weight and any pounds lost at this point will be promptly regained. As you can imagine, the combination of sweat bathing and cooling conditions the body, and a well-tuned body is more resistant to colds, disease and infection. In cold weather, the warm glowing feeling lingers for hours, while in hot climates the body seems cooler than before the sweat bath.