A sauna (or as Finnish [ˈsɑunɑ]) is a small room or house designed as a place to experience dry or wet heat sessions, or an establishment with one or more of these and auxiliary facilities. These facilities derive from the Finnish sauna. The word "sauna" is also used figuratively to describe an unusually hot or humid environment.
The steam and high heat caused bathers to perspire. The Finns also used a vihta [ˈvihtɑ] (Western dialect, or vasta [ˈvɑstɑ] in Eastern dialect), which is a bundle of birch twigs with fresh leaves, to gently slap the skin and create further stimulation of the pores and cells.
The Finns also used the sauna as a place to cleanse the mind, rejuvenate and refresh the spirit, and prepare the dead for burial. The sauna was (and still is) an important part of daily life, and families bathed together in the home sauna. Indeed, the sauna was originally meant to be a place of mystical nature where gender/sex differences did not exist. Because the sauna was often the cleanest structure and had water readily available, Finnish women also gave birth in the sauna.
Although the culture of sauna nowadays is more or less related to Finnish culture, it's important to note that the evolution of sauna has happened around the same time both in Finland and the Baltic countries sharing the same meaning and importance of sauna in daily life. The same sauna culture is shared in both places still to this day.
When the Finns migrated to other areas of the globe they brought their sauna designs and traditions with them, introducing other cultures to the enjoyment and health benefits of sauna. This led to further evolution of the sauna, including the electric sauna stove, which was introduced in the 1950s and far infrared saunas, which have become popular in the last several decades.
Many North American and Western European college/university physical education complexes and many public sport centers and gyms include sauna facilities. They may also be present at public and private swimming pools. This may be a separate area where swim wear may be taken off or a smaller facility in the swimming pool area where one should keep the swim wear on.
Under many circumstances, temperatures approaching and exceeding 100 °C (212 °F) would be completely intolerable. Saunas overcome this problem by controlling the humidity. The hottest Finnish saunas have relatively low humidity levels in which steam is generated by pouring water on the hot stones. This allows air temperatures that could boil water to be tolerated and even enjoyed for longer periods of time. Steam baths, such as the hammam, where the humidity approaches 100%, will be set to a much lower temperature of around 40 °C (104 °F) to compensate. The "wet heat" would cause scalding if the temperature were set much higher.
Finer control over the temperature experienced can be achieved by choosing a higher level bench for those wishing a hotter experience or a lower level bench for a more moderate temperature. A good sauna has a relatively small temperature gradient between the various seating levels.
Good manners require that the door to a sauna not be kept open so long that it cools the sauna for those that are already in it. Leaving the door even slightly ajar or keeping it open for more than a few seconds will significantly cool down the relatively small amount of hot air inside the sauna.
Infrared saunas are growing in popularity, using far infrared rays emitted by infrared heaters to create warmth.
In Finland, the sauna was thought of as a healing refreshment. The old saying goes: "Jos ei viina, terva tai sauna auta, tauti on kuolemaksi." ("If booze, tar, or the sauna won't help, the illness is fatal.") The Finnish sauna is not thought as an easy way to get physical exercise, and it is not intended for weight loss; in fact, it predates these modern ideas.
In Finnish and Latvian sauna culture, a beer afterwards is thought to be refreshing and relaxing. Pouring a few centilitres of beer into the water that is poured on the hot stones releases the odor of the grain used to brew the beer. This distinctive smell, however, sharply divides Finnish people. Also other scents can be used (for example pine tar or eucalyptus), but using any scents other than birch leaves is frowned upon by the traditionalists. A common method for adding birch leaf scent is to wet the leaves of a vihta in water, and then place the vihta on the hot stones for a second or two. This also conveniently heats the vihta for use to whip the users skin to increase blood circulation. According to Finnish lore, the human body is most beautiful thirty minutes after a sauna.
Social and mixed gender nudity with adults and children of the same family is common in the conventional sauna. Sometimes the sauna is considered not only a sex-free, but also almost a gender-free zone. In the dry sauna and on chairs one sometimes sits on a towel for hygiene and comfort; in the steam bath the towel is left outside. Some hotel sauna facilities and especially cruise ships and/or ferries have an area where refreshments (often alcoholic) are served in conjunction with the sauna/pool area; draping a towel around the waist is generally required in that part of such facilities.
As an additional facility a sauna may have one or more jacuzzis.
Saunas in Estonia have traditionally held a central role in the life of an individual. Ancient Estonias believed saunas were inhabited by spirits. In folk tradition sauna was not only the place where one washed, but also used as the place where brides were ceremoniously washed, where women gave birth and the place the dying made their final bed. On new year's eve a sauna would be held before midnight to cleanse the body and spirit for the upcoming year.
Records and other historical evidence indicate that the Finns built the first wooden saunas in the 5th or 8th century. Early saunas were dug into a hill or embankment. As tools and techniques advanced, they were later built above ground using wooden logs. Rocks were heated in a stone fireplace with a wood fire. The smoke from the fire filled the room as the air warmed.
Once the temperature reached desired levels, the smoke was allowed to clear and the bathers entered. The wood smoke aroma still lingered and was part of the cleansing ritual. This type of traditional smoke sauna was called a savusauna, which means "smoke sauna" in Finnish. Many people find the smell of smoke and wood to be relaxing.
In Finland swimsuits, towels, or any other garments are rarely worn in the sauna. Families often go to the sauna together, which is not considered eccentric since family saunas are an old tradition. In these private saunas swimsuits or towels are never worn. In public saunas it is more common that men and women go to the sauna separately, although people of both sexes may sometimes bathe together, for example in student clubs. Still, saunas are not associated with sex and sexuality. Quite the contrary, historically saunas have been the most sacred places after the church, and most houses which could afford to build a sauna had one. In older times women also used to give birth in the sauna because it was a warm and sterile environment. Children were occasionally born in saunas still in the beginning of the 20th century.
The lighting in a sauna is shady, and some Finns prefer to sit in the sauna in silence, relaxing. The temperature is usually between 80°C (176°F) and 110°C (230°F). Sometimes people make a 'vasta'; (or vihta) they tie together small fresh birch branches (with leaves on) and swat themselves and their fellow sauna bathers with it. One can even buy vihtas from a shop and store them into the freezer for later (winter) use. Using a vasta improves blood circulation, and its birch odour is considered pleasing.
Today there are a wide variety of sauna options. Heat sources include wood, electricity, gas and other more unconventional methods such as solar power. There are wet saunas, dry saunas, smoke saunas, steam saunas, and those that work with infrared waves. There are two main types of stoves: continuous heating and heat storage-type. Continuously heating stoves have a small heat capacity and can be heated up on a fast on-demand basis, whereas a heat storage stove has a large heat (stone) capacity and can take much longer to heat.
Fire-heated saunas are common in cottages, where the extra work of maintaining the fire is not a problem. Many think of them as giving a superior experience compared to electric saunas.
Many cultures have close equivalents, such as the North American First Nations (in Canada) or Native American (in the United States) sweat lodge, the Turkish hammam, Roman thermae, Nahuatl (Aztec) temescalli, Maya temazcal, Russian banya, Estonian saun, the Jewish Shvitz, African Sifutu, Swedish bastu, Japanese Mushi-Buro, and the Korean jjimjilbang. Public bathhouses that often contained a steam room were common in the 1700s, 1800s and early 1900s and were inexpensive places to go to wash when private facilities were not generally available.
In Finland, Estonia, Latvia and Russia sauna-going plays a central social role. These countries boast the hottest saunas and the tradition of beating fellow sauna-goers with leafy, wet birch bunches ('vasta' or 'vihta' in Finnish, 'viht' in Estonian, 'slota' in Latvian, 'venik' in Russian). In Russia, public saunas are strictly single sex, while in Finland, Estonia and Latvia, both types occur. During wintertime, Finns often run outdoors for either ice swimming or, in the absence of lake, just to roll around in the snow naked and then go back inside. This is popular in Estonia and Latvia as well.
In Sweden saunas are found in many places, and are known as 'bastu' (from 'badstuga' = bath house). Public saunas are generally single-sex; nudity is obligatory.
In Germany and Austria nudity is strictly enforced in public saunas, as is the covering of benches with towels. Separate single-sex saunas for both genders are rare, most places offer women-only and mixed-gender saunas, or organise women-only days for the sauna once a week. Loud conversation is not usual as the sauna is seen as a place of healing rather than socialising. Contrary to Scandinavian countries, pouring water on hot stones to increase humidity (Aufguss, lit: "Onpouring") is not normally done by the sauna visitors themselves, but rather by a person in charge (the Saunameister), either an employee of the sauna complex or a volunteer. Aufguss sessions can take up to 10 minutes, and take place according to a schedule. During an Aufguss session the Saunameister uses a large towel to circulate the hot air through the sauna, intensifying sweating and the perception of heat. Once the Aufguss session has started it is not considered good manners to enter the sauna, as opening the door would cause loss of heat (Sauna guests are expected to enter the sauna just in time before the Aufguss. Leaving the session is allowed, but grudgingly tolerated). Aufguss sessions are usually announced by a schedule on the sauna door. An Aufguss session in progress might be indicated by a light or sign hung above the sauna entrance. Cold showers or baths shortly after a sauna, as well as exposure to fresh air in a special balcony, garden or open-air room (Frischluftraum) are considered a must.
The Benelux has a similar attitude to saunas as Germany, as almost all public saunas offer only mixed-gender nudity-compulsory facilities. A lot of these saunas do offer occasional women-only or bathing suit days or mornings for people who are less comfortable with mixed-gender nudity. Using a towel to keep to completely cover the bench you're lying on is also compulsory, as is showering between a sauna and entering any of the pools (cold water pool, swimming pool or whirlpool) for hygienic purposes.
In German-speaking Switzerland, customs are generally the same as in Germany and Austria, although you tend to see more families (parents with their children) and young people. Also in respect to socialising in the sauna the Swiss tend more to be like the Swedes or Finns. Also in German speaking countries, there are many facilities for washing after using the sauna, with 'dunking pools' (pools of very cold water in which a person dips themselves after using the sauna), showers. In some saunas and steam rooms, scented salts are given out which can be rubbed into the skin for extra aroma and cleaning effects. In French-speaking Switzerland, customs are less rigid. Often, patrons have their choice of bathing nude or clothed. Other facilities offer nude single-sex saunas, nude mixed-gender saunas, and clothed mixed-gender saunas on the same premises.
In France, the United Kingdom, and much of southern Europe, single-gender saunas are the most common type. Nudity is tolerated in the segregated saunas but usually forbidden in the mixed saunas. This is a source of confusion when residents of these nations visit Germany and Austria or vice versa. Sauna sessions tend to be shorter and cold showers are shunned by most. In the United Kingdom, where public saunas are becoming increasingly fashionable, the practice of alternating between the sauna and the jacuzzi in short seatings (considered a faux pas in Northern Europe) has emerged.
Saunas in northeastern Italian regions Friuli and Trentino-Alto Adige/Südtirol, as in Slovenia and Croatia, have setups similar to those in Germany and Austria, and are perhaps a bit more relaxed about enforcing rules: mixed-gender saunas and patrons have their choice of bathing nude or clothed
Hungarians see the sauna a part of a wider spa culture. Here too attitudes are less liberal, mixed-gender people are together and they wear swimsuits. Single-sex saunas are rare, as well as those which tolerate nudity.
In Portugal, the steam baths were commonly used by the Castrejos people, prior to the arrival of the Romans in the western part of the Iberian peninsula. The historian Estrabão spoke of Lusitans traditions that consisted of having steam baths sessions followed by cold water baths. Pedra Formosa its the original name given to the central piece of the steam bath in pre-Roman times.
In Central America, particularly in the highlands of southern Mexico and Guatemala, a version of the sauna indigenous to the Americas, called temazcal, is quite popular. The temazacal is usually made of clay or stone, and has a low ceiling. The temazcal structure is usually shared by an extended family unit. Unlike European sauna culture, temazcal is an individual rather than social activity. One washes in the temazcal, with soap, or in a more traditional setting, with herbs and medicinal bushes. One uses the temazacal only in the evening, so that upon exiting one can feel the chill of the cold evening air (temperature can fall below freezing at high altitudes). One usually bathes in the temazacal 2-3 times a week.
In Africa, on the whole, saunas are kept at a much lower temperature than in Europe.
In Korea, saunas are essentially public bathhouses. Various names are used to describe them, such as the smaller mogyoktang, outdoor oncheon, and the elaborate jjimjilbang. The word 'sauna' is used a lot for its 'English appeal', however it does not strictly refer to the original Scandinavian steam rooms that have become popular throughout the world. The konglish word sauna (사우나) usually refers to bathhouses with Jacuzzis, hot tubs, showers, steam rooms, and related facilities.
In Japan, many saunas exist at sports centers and public bathhouses (sentō). The saunas are almost always gender separated, often required by law, and nudity is a required part of proper sauna etiquette. While right after World War II, public bathhouses were commonplace in Japan, the number of customers have dwindled as more people were able to afford houses and apartments equipped with their own private baths as the nation became wealthier. As a result many sentōs have added more features such as saunas in order to survive.
In the United States, common sauna culture is not widespread outside of the Upper Peninsula of Michigan and parts of Minnesota, Wisconsin, and Iowa, which are home to large populations of Finnish Americans. Elsewhere, sauna facilities are normally provided at health clubs and at hotels, but there is no tradition or ritual to their use, and many people fail to appreciate their benefits. To avoid liability, many saunas operate at only moderate temperatures and do not allow pouring water on the rocks. There is little enforced sauna etiquette in the United States, with the exception that mixed-sex saunas require some clothing such as a bathing suit to be worn. These are uncommon, however, as most saunas are in the changing rooms of health clubs or gyms. There are few restrictions on use, and Sauna users may enter and exit the sauna as they please, be it nude with a towel, dripping wet in swimsuits or even in workout clothes. Besides the Finnish Americans, the older generation of Korean-Americans still uses the saunas as it is available to them.
The Korean-American communities in United States that have settled in urban cities such as Los Angeles county still use the sauna on a weekly basis. These businesses are common in the Koreatown district of Los Angeles. Saunas in Koreatown are built much like their predecessors in Korea, although on a smaller scale. Some saunas offer rooms that have special elements that provide different type of detoxification and/or relaxation i.e. salt rooms, jade rooms, clay fomentation room, charcoal rooms, and various steam rooms.
One word in Finnish, strictly connected to sauna, is löyly. It is difficult to translate precisely, but denotes the heat of the sauna room, especially the heat derived from throwing water on the hot stones of the sauna oven. Originally this word meant spirit or life. In many languages which are related to Finnish, there is a word corresponding to löyly. The closest example appears in the Estonian language, leil. The same meaning of "spirit" is also used in Latvian. Another example is lil in Ostyak, which means soul, pointing to the sauna's old, spiritual essence.
There still exists an old saying, "saunassa ollaan kuin kirkossa," – you should be in the sauna as in a church.
Saunatonttu, literally translated sauna elf, is a little gnome that was believed to live in the sauna. He was always treated with respect, otherwise he might cause much trouble for people. It was customary to warm up the sauna just for the gnome every now and then, or to leave some food outside for him. It is said that he warned the people if a fire was threatening the sauna, or punished people who behaved improperly in it – for example slept, or played games, argued, were generally noisy or behaved otherwise "immorally" there.
In Thailand, women spend hours in a make-shift sauna tent during a month following child birth. The steam is typically infused with several herbs. It is believed that the sauna helps the new mother's body return to its normal condition faster.
Saunas can be dangerous, as heat prostration or the even more serious hyperthermia (heat stroke) can result. Children and older persons who have heart disease or seizure disorders or those who use alcohol or cocaine are especially vulnerable. Prolonged stay in a sauna may lead to loss of electrolyte from the body, the same as after rigorous exercise. Risks of dehydration leading to heat stroke in more sensitive individual can occur and may be reduced by regular sipping of water or isotonic drinks, but not alcohol, during the sauna. Sauna bathing and heavy drinking, and also sauna bathing during hangover phase can undoubtedly create real health risks.
Many of the sauna therapeutic trials used a regular schedule of at least 5 days a week and often daily for one, to three months, then several times a week for extended periods. In some countries the local gymnasium is usually the closest and most convenient and some pool, major sport, or even resort complexes also contain a sauna. Therapeutic Sauna is often carried out in conjunction with physiotherapy or hydrotherapy, gentle exercises within the capability of the person without exacerbating symptoms.
A steam sauna can take 30 minutes to heat up when first started. Some users prefer taking a warm shower beforehand to speed up perspiration in the sauna. When in the sauna users often sit on a towel for hygiene and put a towel over the head if the face feels too hot but the body feels comfortable. Most adjustment of temperature in a sauna comes from,
It is cooler on the lower benches, and away from the heater elements, as the heat rises and will be hotter higher up. Provided the sauna is not crowded, lying on a bench is considered preferable as it gives more even temperature over the body. Users increase duration and the heat gradually over time as they adapt to sauna.
Perspiration is a sign of autonomic responses trying to cool the body. Users are advised by sauna operators that at any time it feels unbearably hot, or they feel faint or ill, to go straight outside and sit in the cool, have a cool drink of water, when able have a mild shower to cool down. Some saunas have a thermostat to adjust temperature but the management and other users usually expect to be be consulted, first. The sauna heater and rocks are very hot - users know to stay well clear to avoid injury particularly when water is poured on the sauna rocks which creates an immediate blast of steam. Combustibles on or near the heater including oils have been known to result in fire. Wet floors can be slippery, - when entering, leaving or moving around the sauna. Contact lenses dry out in the heat. Jewellery or anything metallic (including glasses) will get hot in the sauna and can cause discomfort or burning. Temperature on different parts of the body can be adjusted by shielding from the steam radiator with a towel. Shielding the face with a towel has been found to reduce the perception of heat. Few people can sit directly in front of the heater without feeling too hot from radiant heat, but their overall body temperature may be insufficient. As the person’s body is often the coolest object in a sauna room, steam will condense into water on the skin; this can be confused with perspiration. In an infrared dry sauna, the heaters produce infrared rays that penetrate the skin layers and heat more deeply, It is the user that heat ups not so much the room, so it will be cooler. For safety reasons water is not placed on these types of heaters.
Cooling down is part of the sauna cycle and is as important as the heating. Among users it is considered good practice to take a few moments after exiting a sauna before entering a cold plunge, and to enter a plunge pool by stepping into it gradually, rather than immediately immersing fully. Until used to having a full cold shower, warm ones are used gradually make it colder so that the shock is not so great. After a shower, feeling cold or shivering indicates it is enough, the shiver is a sign of the autonomic responses, trying to warm the body. This is considerd a signal for the sauna again. If however illness is felt later or during that day, a less hot sauna and warmer longer cool down is tried then the next day . In summer any after effects like headache or nausea can come from insufficient cool down after the sauna, or from dehydration, failure to drink enough fluids. Sleep disturbances can also occur if not cooled down properly, even though not feeling hot, the heat in the core of the body may disrupt sleep as the body tries to cool at night. In summer a session is often started with a cold shower.
Some detoxification studies sauna for about 10 minutes a time, followed by full cool down, to 5 minutes depending on the time of year, repeated 3 times each daily session. Three times in a session is considered an average number of heat/cool cycles.
Therapeutic sauna is the use of sauna for health purposes. It requires cycles of both hot and cold, in a predetermined manner to bring about therapeutic change. Usually it should be carried out daily over a month or so. With chronically ill people the amount of exercise that they can initially tolerate in recuperation may be insufficient to burn off excess stress hormones, so another way is needed to achieve this. The temperature changes of therapeutic sauna can help and this has other benefits as well. When first used gradual increases in heating and cooling are recommended. Therapeutic sauna reduces stress hormones and the cardiac workload is considered about half that of a walk, so initial exposure time is important also.
The hypothalamus in our brain controls the balance homeostasis of the autonomic nervous system between the ACTION sympathetic and the RELAXATION parasympathetic nervous tone. The well known ‘fight or flight’ stress response produces hormones intended to be burnt off by action, but in a modern lifestyle such hormones may remain in the system. Chronic illness can be associated with altered sympathetic nervous function. Continual stress may alter the balance point of homeostasis, as can some persistent viruses. Allostatic load measurement is an emerging science of measuring with physiological tests the accumulated effect of all types of stress, over time, on the body.
Four different patterns of dysfunctional allostasis have been identified, each associated with certain chronic conditions. When allostasis (the process of maintenance of homeostasis, adaptation, and survival) is dysfunctional the balance point is shifted and persistent symptoms may result. In one form of dysfunction the hypothalamus and HPA axis responsible for producing hormones is found to be hypo functioning with effects on the sympathetic system and the immune system. In particular production of hypothalamus controlled HPA axis hormones such as ACTH and cortisol; as well other hormones are affected. Other patterns of dysfunctional allostasis involve conditions where there is failure to habituate or adapt to stress and another pattern with high levels of stress hormones, causes conditions such as hypertension or high blood pressure.
Therapeutic sauna has been shown to aid adaptation, reduce stress hormones, lower blood pressure and improve cardiovascular conditions.
Contraindications to sauna include unstable angina pectoris, recent myocardial infarction, and severe aortic stenosis. Sauna is safe, however, for most people with stable coronary heart disease. It is not harmful to the aged or young even infants over 3 months in moderation and does not affect wound healing. Sauna use may reduce the incidence of the common cold, and temporarily relieve the symptoms. It increases performance in endurance sport, increases plasma volume and red cell volume in athletes, decreased systolic blood pressure, significantly improved exercise tolerance, increased peak respiratory oxygen uptake, and enhanced anaerobic threshold in chronic conditions.
Sauna plus multidisciplinary treatment may reduce chronic pain more effectively than multidisciplinary treatment alone. Sauna reduces chronic pain more effectively than cognitive behaviour therapy. It is indicated for rheumatic pain (with cold shower) but not for neuropathic pain. Is effective for appetite loss and mild depression. Indicated in reducing symptoms in Chronic Fatigue Syndrome, and rheumatoid arthritis, and indicated for anorexia nervosa. Sauna improves function in conditions such as, congestive heart failure, and high blood pressure, improves vasodilation, improves heart arrhythmia, and reduces heart rate on exercise. Sauna has been proposed for treatment of other conditions such as, glaucoma, Sjogren syndrome, chronic fatigue syndrome, fibromyalgia, anorexia nervosa, obstructive lung disease, recuperation after childbirth, and also for lifestyle related diseases of, diabetes, arteriosclerosis, obesity, hypertension, hyperlipidemia, atherosclerosis and smoking induced symptoms. Sauna has also been found to reduce levels of stress hormones adrenalin and noradrenalin and to increase levels of ACTH, cortisol and beta endorphin. Sauna has been found to increase the hormone testosterone in men. Sauna also found to reduce prostaglandin F2alphaand protect against oxidative stress. It enhances activation of monocytes to bacteria and endotoxins.
Other benefits of saunas: It has shown that regular saunas combined with exercise therapy can efficiently clear organic chemicals, solvents, drugs, pharmaceuticals even PCBs and heavy metals from the body. In addition a sauna followed by a cold shower has been shown to reduce pain in rheumatoid arthritis where pain is mediated by sensitised c-fibre sympathetics. Regular saunas have also been found to improve micro circulation reduce vasoconstriction and hypertension. Many symptoms of chronic illnesses may be due to vasoconstriction effects eg. cold sensitivity, pain even mood states, and sauna improves microcirculation and blood supply to constricted areas. Research has also shown that adaptation to cold through short term cold stimulus, as in cold swimming, immersion (or showers) has the added benefit of improving the body's anti oxidant capabilities, with increases in glutathione and reduction of uric acid, which may mean better handling of the stresses of illness. Those that are shown to involve reduced glutathione or increased glutathione use, include; cardiovascular conditions, pulmonary diseases, diabetes, inflammatory bowel diseases, cancer, osteoporosis, aging, and after pesticide exposure. Conditions involving oxidative stress include neuro degenerative diseases, CFS, bone fracture and others. Conditions in which increased uric acid may be a risk factor include, gout, metabolic disease and vascular diseases.
A reported study from the Thrombosis Institute in London into the effects of the cold bathing found that volunteers that followed a disciplined daily regime had increased immune white blood cells and the level of the bodies natural blood thinning enzymes substantially increased, improving micro circulation. It also stimulated the production of hormones such as testosterone in men, and boosted women's production of oestrogen. Cold water immersion raises thresholds of pain tolerance, and aids adaptation to cold, reduces muscle spasm, can influence the frequency of respiratory infections and improve subjective well-being. It may cause an immunological modulation in terms of the Th1-type pattern, which is a proinflammatory cytokine profile. It is involved in diseases such as arthritis, diabetes, inflammatory myopathies, inflammatory bowel disease, psoriasis, CFS, fibromyalgia, chronic pain, fatigue conditions, auto immune disease and other inflammatory conditions. Cold water adaptation reduced total cholesterol and LDL cholesterol, lowered plasma viscosity and blood pressure rate product. Cold water immersion reduces recovery time in athletes, enhances repeat performance and reduces exercise induced muscle damage.
Cold water exposure challenges both the neuro-endocrine and the immune systems, reduces stress hormones and attenuates their response. Increases ADH and cortisol and increases immunomodulatory cytokines. Cold water exposure and adaptation can modify the sensory functions of hypothalamic thermoregulatory centres to lower heat loss and produce less heat during cold exposure and have immunostimulating effects. The thermogenic action of adrenaline in cold exposure produces heat and may reduce this stress hormone. An important effect is the ability of sauna to use up excess sympathetic nerve tone in both the central and peripheral nervous systems and just as importantly use up excess levels of local tissue hormones involved in feedback loops to the hypothalamus, thus aiding recovery in chronic illness. The therapeutic sauna with hot cycle followed by a cold cycle brings the benefits of both, forces all the blood to flow gently and evenly outwards to the skin to cool off in the heat of the sauna, and then forces it to flow evenly inwards to protect and heat the vital organs of the body when suddenly cooled. With sauna, sections of the body with chronically deprived blood, increase supply and reduce oxidative stress. As the blood supply cycles into the organs and then out to the skin it acts like a pump bringing stored chemical toxins from remote areas of the body through the microcirculation to the skin to be removed in sweat. The skin of our bodies is in effect another eliminatory organ so even when other organs are compromised in chronic illnesses or contamination, the skin through sweating can rid the body of such chemicals and toxins. The parasympathetic system governs sweat glands secretion and is increased by sauna. Sweating is used to eliminate toxic metals, just as iron loss in sweat increases with exercise in athletes. It has been shown with drugs such as caffeine, that delayed metabolic (organ) clearance was offset by a sizeable elimination in (skin) sweat by sauna. Sweat tests have shown pharmaceutical drugs are eliminated in sweat, narcotics, alkaloids and barbiturates are eliminated in sweat, and elimination increased with heat. Sweat analysis is also used for diagnosis of some disease, toxic metal excretion in sweat is used in diagnosis of chronic disease the result of contamination, and sweating used to eliminate toxic metals. The beneficial effects of therapeutic sauna are both temporary and long term, some benefits will last about 24 hrs. Adaptation and detoxification will occur after longer use when the practice can be suspended or continued if beneficial.