Would you believe sitting in a sauna could be the most vigorous activity you've had all day? The heat makes an artificial "fever" and every organ of the body goes into action.
While relaxed on the outside, your inner organs are as active as though you were running! Simultaneously you are being cleansed from inside out by the skin, your largest organ and its excretion, sweat.
The sauna is a natural approach to a healthier and happier lifestyle. A few of the marvellous benefits of the sauna:
1. Refreshes your skin, keeping it clean and pliant
2. Revitalises the body and mind
3. Deep cleans ridding your body of wastes (20 minutes in the sauna equals 24 hours work by the kidneys)
4. Releases stress and tension
5. Relieves nasal, sinus and chest congestion
6. Reduces aches and pains in joints by removing lactic acid
7. Beneficial for mild cases of hypertension
8. Effective de-toxifier
9. Flushes out toxic metals
10. Combined with brushing removes accumulated dead skin
11. Impurities within internal organs are flushed out
12. Helps kill viruses and bacteria which can't survive in higher than normal body temperatures
13. Recovery from illness becomes easier and quicker due to increased metabolism rates
14. Pituitary accelerates metabolism which increases growth rates and sex drive
15. Positive effects from negative ions of steam
Sweating is as essential to our health as eating and breathing. It accomplishes three important things:
1. rids the body of wastes,
2. regulates the critical temperature of the body at 37 degrees C (98.6 degrees F),
3. helps keep the skin clean and pliant.
In this day and age, many people simply don't sweat enough. This makes the Sauna all the more desirable. Antiperspirants, artificial environments, smog, synthetic clothing, and a physically idle lifestyle all conspire to clog skin pores and inhibit the healthy flow of sweat. These detrimental effects are reversed in a Sauna, although the physiological effects vary due to the amount of heat and humidity. For example, the body sweats more profusely in a hotter (80-100 degree C) and drier (15-25%) atmosphere.
When you lounge in a Sauna, heat sensitive nerve endings produce acetylcholine, a chemical which alerts the 2.3 million sweat glands embedded in the skin. But not all of them respond. The aprocine sweat glands, located in the pubic and armpit areas, are activated only by emotional stimuli. They carry a faint scent whose purpose is believed to arouse the sex drive.
Nevertheless, the eccrine sweat glands, by far the most abundant, respond to heat. During a 15-minute sauna, about one litre of sweat is excreted, depending upon the individual. (Normal daily rate ranges from .5 to 1.5 litres.) Eccrine sweat is clear and odourless; any odour is only created by the presence of bacteria. One of its chief functions is to cool the body by evaporation, although there are also eccrine glands on the palms of your hands and soles of your feet which react to emotional stimuli.
A third kind of sweat, called insensible perspiration, originates inside and works its way through blood and other cells to the surface of the skin. Even without a Sauna, approximately a litre of insensible perspiration evaporates each day.
Sweat also has the function of being a judicious garbage collector. During a 15-minute sauna, sweating can perform the heavy metal excretion that would take the kidneys 24 working hours. Ninety-nine percent of what sweat brings to the surface of the skin is water, but the remaining one percent is mostly undesirable wastes. Excessive salt carried by sweat is generally believed to be beneficial for cases of mild hypertension. Some mental hospitals use saunas in their rehabilitation programs to pacify patients.
A metabolic by-product, urea, if not disposed of regularly, can cause headaches, nausea and, in extreme cases, vomiting, coma and even death. Sweating is such an effective de-toxifier that some physicians recommend home saunas to supplement kidney machines. Sweat also draws out lactic acid which causes stiff muscles and contributes to general fatigue. Sweat flushes out toxic metals such as copper, lead, zinc and mercury which the body absorbs in polluted environments.
Because it eliminates, the skin is sometimes called the "third kidney." It is far more complex than the kidney or any other organ except the brain. It is composed of blood vessels, nerve endings, vessels for carrying Iymph, pigmentation, oil glands, hair follicles, cells that waterproof and deny entry to bacteria and, of course, the tubular, coiled sweat glands. It is so important that death by accumulated poisons occurs in a matter of hours if the skin, and its sweat passages, are smothered.
Furthermore, combining Saunaing and brushing with a loofa or rough brush removes flakes of dried skin cells that accumulate on the epidermis. If allowed to remain, they can clog sweat pores and oil passages and result in dry, flaky skin.
Heating and Cooling the Inner Body
Marvelous things happen beneath the skin in the heat of the Sauna. 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.
While the surface temperature of the skin may rise as much as 1O degrees C, inner temperature increases up to 3 degrees C. This is the "fever" that Hippocrates and generations of medical people after him sought, and is created as one reclines in a Sauna! Of course it is unlikely that "any disease" can be cured by fever, but it is 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 centre 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 me 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% 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. Saunaing is not recommended for those suffering from pneumonia or other acute respiratory diseases.
When the body 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 (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! 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. However, Saunas have an indirect effect on weight loss. As you can imagine, the combination of Saunaing 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 Sauna.
Positive Effects of Negative Ions
Physiologically, the presence of negative ions in a Sauna is as important as the heat. The discovery of negative ions a few years ago became headline news in Finland. Until then, the healing power of the sauna was attributed to relaxation and increased circulation. Now, negative ions add startling new possibilities.
Since the early 1950s scientists have suspected that ions play an important role in how the body functions and, consequently, in how we feel. Research has shown that an abundance of negative ions in the air we breathe is highly beneficial, while a lack of ions or a higher ratio of positive to negative can cause physical harm. The role played by ions in everyday life has become intensely topical among researchers in the medical profession. (Read The Ion Effect by Fred Soyka for an excellent discussion on the use of negaive ions in medicine.)
An ion simply a molecule with an electric charge, either positive or negative. Ionization, or ion formation, occurs when enough energy acts on a molecule to cause it to discharge an electron. Because electrons carry a negative charge, the molecule stripped of an electron has a greater positive charge and becomes a positive ion. The lost electron scoots around loose until it attaches itself to another molecule, which causes the new molecule to become negatively charged--a negative ion.
Radioactive substances in the earth's crust and cosmic rays cause most ionization. But fire, crashing water (like water falls and surf), and plants during photosynthesis can produce negative ions as well. Europeans take ion depletions seriously and simple negative ion generators have been installed in many businesses, banks, hospitals, and passenger cars and even airliner cockpits. Furthermore, in the USA, Europe and the Soviet Union, negative ion therapy has been used in treatments to help burn ims heal faster, to cure respiratory diseases, to rid the body of general infections, and even to check the spread of some cancers.
Conversely, scientists have found that if the air is charged with too few negative ions and too many positives, we become anxious, fatigued and tense. This condition is known as "pos-ion poisoning," and often occurs as the result of weather disturbances, central air conditioning, smog, and driving too long within the confines of an automobile. Pos-ion poisoning has, in fact, been linked to heart attacks, aggravated asthma, migraine headaches, insomnia, rheumatism, arthritis, hay fever, and most allergies.
The idea is not to have the best sauna on the block, but to get the entire block in the sauna. Professor Harold Tier; President, Finnish Sauna Society
The medicinal and spiritual values of the Sauna are furthered by its communal character. The Sauna can be a social event - like the coffee shop, neighbourhood bar or picnic - and is probably the healthiest ever offered a group of people.
In a Finnish sauna the human body is exposed to higher temperature than anywhere else in natural surroundings, but only for a short time. The high temperature induces many temporary physiological changes.
The temperature of skin increases in a few minutes to over 40°C, but after the sweating has started - usually in three to five minutes - this temperature declines and starts to rise slowly again. Skin temperature is around 40°C after a 20 minute bath. The temperature of deeper parts of the body increases much less: in rectum and oesophagus the temperature is around 37.5-38°C after a 20 minute sauna bath.
The increased temperature dilates cutaneous capillary vessels and to maintain sufficient blood pressure the cardiac output increases 2-3 fold. Considerable redistribution of cardiac output takes place: Normally the skin blood flow is 5-10 % of the cardiac output, but can increase to 50-70 % in the sauna. Correspondingly, the blood flow of inner organs and muscles decreases. The changes of blood pressure are moderate. Most often a small decrease of systolic and diastolic blood pressure takes place. During the cooling period, especially if it happens vigorously in cold shower or by swimming in ice-cold water, blood pressure rapidly increases. The increase of cardiac load in the sauna is similar to that seen during brisk walking.
The average fluid loss during a sauna bath in around 0.5 kg, which corresponds to less than one per cent weight loss. Sweat contains less salt than does blood, and thus mild sauna-induced increases of blood sodium and potassium have occurred in some, but not in all studies. The concentration of haemoglobin may slightly increase. Taken together, fluid loss during an ordinary sauna bath is relatively small, and it can easily be compensated by drinking a couple of glasses of water. Sauna does not induce significant changes in blood coagulation.
Sauna affects the endocrine system in many ways. According to most studies sauna stimulates the productions of noradrenaline, prolactin, growth hormone and cardiac natriuretic peptide, and activates renin-angiotensin-aldosterone system. The findings on the behaviour ACTH and cortisol are inconsistent and no changes seem to take place in adrenaline, FSH, LH, testosterone or thyroid hormones. The hormonal changes seen in the sauna are similar to those seen in other physical stress situations.
Children in Saunas
Children's ability to tolerate heat is limited, since their skin area/body mass-ratio is high, sweating system is immature and fat layer is thin. Children can, however, take sauna baths totally safely, if some precautions are taken into account. Children's bathing must take place on totally voluntary basis, thermal stress should be limited according to the age (10 min at 70°C is too much for many children at 2-5 years) and the child must be old enough to express discomfort in a way understandable to parents. Twelve per cent of Finnish children have their first sauna bath before the age of one month, 70 % before the age of one year and 95 % before the age of two years. Finnish children belong to the healthiest in the world.