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Benjamin Boster.
Today's episode is from a Wikipedia article titled,
Sauna.
A sauna,
Finnish sauna,
Is a room or building designed as a place to experience dry or wet heat sessions,
Or an establishment with one or more of these facilities.
The steam and high heat make the bathers perspire.
A thermometer in a sauna is typically used to measure temperature.
A hygrometer can be used to measure levels of humidity or steam.
Infrared therapy is often referred to as a type of sauna,
But according to the Finnish sauna organizations,
Infrared is not a sauna.
Areas such as the rocky Orkney Islands of Scotland have many ancient stone structures for normal habitation,
Some of which incorporate areas for fire and bathing.
It is possible some of these structures also incorporated the use of steam in a way similar to the sauna,
But this is a matter of speculation.
The sites are from the Neolithic age,
Dating to approximately 4000 BCE.
Archaeological sites in Greenland and Newfoundland have uncovered structures very similar to traditional Scandinavian farm saunas,
Some with bathing platforms and enormous quantities of badly scorched stones.
The traditional Korean sauna,
Called the Hanjinmak,
Is a dome structure constructed of stone that was first mentioned in the Sejong Silak of the annals of the Jeseong dynasty in the 15th century.
Supported by Sejong the Great,
The Hanjinmak was touted for its health benefits and used to treat illnesses.
In the early 15th century,
Buddhist monks maintained Hanjinmak clinics,
Called Hanjingseo,
To treat sick poor people.
These clinics maintained separate facilities for men and women due to high demand.
Korean sauna culture and kiln saunas are still popular today,
And Korean saunas are ubiquitous.
Western saunas originated in Finland,
Where the oldest known saunas were made from pits dug in a slope in the ground,
And primarily used as dwellings in winter.
The sauna featured a fireplace where stones were heated to a high temperature,
Water was thrown on the hot stones to produce steam and to give a sensation of increased heat.
The first Finnish saunas were always of a type now called savasana,
Smoke sauna.
These differed from present-day saunas in that they were operated by heating a pile of rocks,
Called kiwas,
By burning large amounts of wood for about six to eight hours,
And then letting out the smoke before enjoying the lurlu,
A Finnish term meaning,
Collectively,
Both the steam and the heat of a sauna.
Same term in Estonian is leili.
You can see similarities with the Finnish word.
A properly heated savasana yields heat for up to 12 hours.
As a result of the Industrial Revolution,
The sauna evolved to use a wood-burning metal stove with rocks on top,
Kiwas with a chimney.
Air temperatures averaged around 75 to 100 degrees Celsius,
But sometimes exceeded 110 degrees Celsius in a traditional Finnish sauna.
As the Finns migrated to other areas of the globe,
They brought their sauna designs and traditions with them.
This led to a further evolution of the sauna,
Including the electric sauna stove,
Which was introduced in 1938 by Mettos Ltd.
In Vaasa.
Although sauna culture is more or less related to Finnish and Estonian culture,
The evolution of the sauna took place around the same time in Finland and Baltic countries.
They all have valued the sauna,
Its customs and traditions until the present day.
The sauna became very popular,
Especially in Scandinavian and the German-speaking regions of Europe,
After the Second World War.
German soldiers had experienced Finnish saunas during their fight against the Soviet Union during the Continuation War,
Where they fought in the same side.
Saunas were so important to Finnish soldiers that they built them not only in mobile tents,
But even in bunkers.
After the war,
The German soldiers brought the custom back to Germany and Austria,
Where it became popular in the second half of the 20th century.
The German sauna culture also became popular in neighboring countries such as Switzerland,
Belgium,
The Netherlands and Luxembourg.
Sauna culture has been registered in the representative list of the Intangible Cultural Heritage of Humanity under two entries,
Smoke Sauna Tradition in Voromaa in 2014 and Sauna Culture in Finland in 2020.
The word sauna is an ancient Finnish word referring to both the traditional Finnish bath and to the bathhouse itself.
In Finnic languages other than Finnish and Estonian,
Sauna and cognates do not necessarily mean a building or space built for bathing.
It can also mean a small cabin or cottage,
Such as a cabin for a fisherman.
The word is the best known Finnicism in many languages.
The sauna known in the Western world today originates from Northern Europe.
In Finland there are built-in saunas in almost every house,
Including communal saunas in the older apartment buildings.
Since the 80s private saunas have often been built into the bathrooms of typical Finnish flats and apartment buildings,
Sometimes even in student housing.
There are also a number of public saunas in Finland,
Including Rahaportin sauna,
A sauna located in Tampere that was first established in 1906 by Hermanni and Marija Latanen.
Helsinki even has a sauna built into one of the gondolas of a ferris wheel,
SkyWheel Helsinki.
Under many circumstances,
Temperatures approaching and exceeding 100 degrees Celsius would be completely intolerable and possibly fatal to a person exposed to them for long periods of time.
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 evaporate 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 50 degrees Celsius to compensate.
The wet heat would cause scalding if the temperatures were set much higher.
In a typical Finnish sauna,
The temperature of the air,
The room and the benches are above the dew point even when water is thrown on the hot stones and vaporized.
Thus,
They remain dry.
In contrast,
The sauna bathers are at about 60 to 80 degrees Celsius,
Which is below the dew point,
So that water is condensed on the bathers' skin.
This process releases heat and makes the steam feel hot.
Finer control over the perceived temperature can be achieved by choosing a higher level bench for those wishing for 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.
Doors need to be kept closed and used quickly to maintain the temperature and to keep the steam inside.
Some North American,
Western European,
Japanese,
Russian and South African public sports center and gyms include sauna facilities.
They may also be present at public and private swimming pools.
As an additional facility,
A sauna may have one or more jacuzzi.
In some spa centers,
There are the so-called special snow rooms,
Also known as cold saunas or cryotherapy.
Operating at a temperature of negative 110 degrees Celsius,
The user is in the sauna for a period of only about 3 minutes.
According to the Guinness Book of World Records,
The world's largest sauna is the Koi sauna in the Thurman and Badeveld Sinsheim,
Germany.
It measures 166 square meters,
Holds 150 people,
And sports a koi aquarium.
The title may now belong to Cape East Spa in Havaranda,
Sweden,
Which also holds 150 people,
But is more spacious.
However,
In Czelotz,
South Poland,
There is now a sauna for 300 people,
Sporting light shows,
Theater,
And needing several sauna masters.
A modern sauna with an electric stove usually takes about 15 to 30 minutes to heat up.
Some users prefer taking a shower beforehand to speed up perspiration in the sauna.
When in the sauna,
People often sit on a towel for hygiene and put a towel over their heads if the face feels too hot,
But the body feels comfortable.
In Russia,
A felt banya hat may be worn to shield the head from the heat.
This allows the wearer to increase the heat on the rest of the body.
The temperature of one's bath can be controlled via the amount of water thrown on the stove.
This increases humidity so that sauna bathers perspire more copiously.
The length of one's stay in the sauna.
Positioning.
The higher benches are hotter,
Whereas the lower benches are cooler.
Children often sit on the lower benches.
The heat is greatest closest to the stove.
Heating from the air is lower on the lower benches as the hot air rises.
The heat given by the steam can be very different in different parts of the sauna.
As the steam rises directly upwards,
It spreads across the roof and travels out towards the corners,
Where it is then forced downwards.
Consequently,
The heat of fresh steam may sometimes be felt most strongly in the furthest corners of the sauna.
Users increase the duration and the heat gradually over time as they adapt to the sauna.
When pouring water onto the stove,
It cools down the rocks,
But carries more heat into the air via advection,
Making the sauna warmer.
Perspiration is a result of autonomic responses trying to cool the body.
Users are advised to leave the sauna if the heat becomes unbearable or if they feel faint or ill.
Some saunas have a thermostat to adjust the temperature,
But the owner of the sauna and the other bathers expect to be consulted before changes are made.
The sauna stove and rocks are very hot.
One must stay well clear of them to avoid burns,
Particularly when water is thrown on the rocks,
Which creates an immediate blast of steam.
Combustibles on or near the stove have been known to cause fires.
Contact lenses dry out in the heat.
Jewelry or anything metallic,
Including glasses,
Will get hot in the sauna and can cause discomfort or burning.
The temperature on different parts of the body can be adjusted by shielding one's body with a towel.
Shielding the face with a towel has been found to reduce the perception of heat.
Some may wish to put an additional towel or a special cap over the head to avoid dryness.
Few people can sit directly in front of the stove without feeling too hot from the radiant heat,
But this may not be reflected in their overall body temperature.
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.
Cooling down by immersing oneself in water in a shower,
Lake,
Or pool is a part of the sauna cycle and is as important as the heating.
However,
It is advisable that healthy people and heart patients alike should take some precautions if plunging into very cold water straight after coming from the hot room as the rapid cooling of the body produces considerable circulatory stress.
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 or a lake by stepping into it gradually,
Rather than immediately immersing oneself fully.
In summer,
A session is often started with a cool shower.
In some countries,
The closest and most convenient access to a sauna is at a gymnasium.
Some public pools,
Major sports centers,
And resorts also contain a sauna.
Therapeutic sauna sessions are often carried out in conjunction with physiotherapy or hydrotherapy.
These are gentle exercises that do not exacerbate symptoms.
There has been widespread research into the health benefits and risks that come from sauna usage.
Most studies have focused on the Finnish sauna specifically.
Sauna bathing leads to mild heat stress,
Which activates heat shock proteins responsible for repairing misfolded proteins,
Promoting longevity,
As well as protection against muscle atrophy and chronic illness.
There is evidence that long-term exposure to Finnish-style sauna is correlated with a reduced risk of sudden cardiac death and that risk reduction increases with duration and frequency of use.
This reduction is more pronounced when sauna bathing is combined with exercise,
Compared with either of these practices alone.
Tentative evidence supports that heat stress from saunas is associated with reduced blood pressure and arterial stiffness and therefore also decrease the risk of cardiovascular disease.
These benefits are more pronounced in persons with low cardiovascular function.
Evidence exists for the benefit of sauna on people with heart failure.
Frequent Finnish-style sauna usage,
4-7 times per week,
Is associated with a decreased risk of neurovascular diseases,
Including Alzheimer's disease and stroke.
Relative to those individuals who used sauna once per week.
Individuals suffering from musculoskeletal disorders could have symptomatic improvement from sauna,
And it could be beneficial for glaucoma.
It also is associated with a reduced risk and symptom relief from the symptoms of respiratory illness.
Weight loss in obese people and improvement of appetite loss,
Present with normal body weight,
Can also be achievable with sauna bathing.
Evidence for the use of sauna for depression or skin disorders is insufficient,
But the frequency of sauna sessions is correlated with a diminished risk of developing psychosis,
And it might be beneficial for psoriasis.
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,
Infrared saunas,
Smoke saunas,
And steam saunas.
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.
Smoke sauna is one of the earliest forms of the sauna.
It is simply a room containing a pile of rocks,
But without a chimney.
A fire is lit directly under the rocks,
And after a while the fire is extinguished.
The heat retained in the rocks and the earlier fire becomes the main source for heating the sauna.
Following this process,
The ashes and embers are removed from the hearth,
The benches and floor are cleaned,
And the room is allowed to air out and freshen for a period of time.
The smoke deposits a layer of soot on every surface,
So if the benches and backrests can be removed while the fire is alight,
The amount of cleaning necessary is reduced.
Depending on the size of the stove and the airing time,
The temperature may be low,
About 60 degrees Celsius,
While the humidity is relatively high.
The tradition almost died out in Finland,
But was revived by enthusiasts in the 1980s.
These are still used in present-day Finland by some enthusiasts,
But usually only on special occasions such as Christmas,
New Year's,
Easter,
And Midsummer.
Smoke saunas are popular in southern Estonia,
And smoke sauna tradition in Vuramaa was added into UNESCO Intangible Cultural Heritage list in 2014.
The smoke sauna stove is also used with a sealed stone compartment and chimney,
A heat storage stove,
Which eliminates the smoke odor and eye irritation of the smoke sauna.
A heat storage stove does not give up much heat in the sauna before bathing,
Since the stone compartment has an insulated lid.
When the sauna bath has started and the Lurlu shutter opened,
A soft warmth flow into the otherwise relatively cold sauna.
This heat is soft and clean because,
Thanks to combustion,
The stove stones glow red,
Even white-hot,
And are freed of dust at the same time.
When bathing,
The heat storage sauna will become as hot as a continuous fire-type sauna,
80 to 110 degrees Celsius,
But more humid.
The stones are usually durable,
Heat-proof,
And heat-retaining peridotite.
The upper part of the stove is often insulated with rock wool and fire bricks.
Heat storing stoves are also found with electric heating,
With similar service but no need to maintain a fire.
A continuous fire stove instead of stored heat is a relatively recent invention.
There is a firebox and a smokestack,
And stones are placed in a compartment directly above the firebox.
It takes a shorter time to heat than the heat storage sauna,
About one hour.
A fire-heated sauna requires manual labor in the form of maintaining the fire during bathing.
The fire can also be seen as a hazard.
Fire-heated saunas are common in cottages,
Where the extra work of maintaining the fire is not a problem.
The most common modern sauna types are those with electric stoves.
The stones are heated up and kept on temperature using electric heating elements.
There is a thermostat and a timer,
Typically with 8 hours maximum delay time,
Followed by one hour's continuous heating time on the stove.
This type of heating is generally used only in urban saunas.
Far-infrared saunas utilize infrared light to generate heat.
Unlike traditional saunas that heat the body indirectly through the air or by conduction from heated surfaces,
Far-infrared saunas use infrared panels or other methods,
Like a sauna blanket,
That emit far-infrared light,
Which is absorbed by the surface of the skin.
The heat produced by far-infrared saunas is generally lower,
Making it more tolerable for people who cannot withstand the high temperatures of traditional saunas.
Infrared heat penetrates more deeply into fat in the neuromuscular system,
Resulting in a more vigorous sweat at lower temperatures than traditional saunas.
These effects are favorable for the neuromuscular system to recover from maximal endurance exercise.
Although cultures in all corners of the world have imported and adapted the sauna,
Many of the traditional customs have not survived the journey.
Today,
Public perception of saunas,
Sauna etiquette,
And sauna customs vary hugely from country to country.
In many countries,
Sauna going is a recent fashion and attitudes towards saunas are changing,
While in others,
Traditions have survived over generations.
In Africa,
The majority of sauna facilities are found in a more upmarket hotel,
Spa,
And health club environments,
And predominantly share both sauna heater technology and design concepts as applied in Europe.
Even though outdoor temperatures remain warmer and more humid,
This does not affect the general application or intended sauna experience offered within these commercial environments,
Offering a traditional sauna and or steam shower experience.
In Iran,
Most gyms,
Hotels,
And almost all public swimming pools have indoor saunas.
It is very common for swimming pools to have two saunas,
Which are known in Persian as koshk sauna,
Dry sauna,
And bukar sauna,
Steam sauna.
With the dry type customarily boasting a high temperature.
A cold water pool,
And or more recently a cold jacuzzi,
Is almost always accompanied and towels are usually provided.
Adding therapeutic or relaxing essential oils to the rocks is common.
In Iran,
Unlike Finland,
Sitting in a sauna is mostly seen as part of the spa club culture,
Rather than a bathing ritual.
It is most usually perceived as a means for relaxation or detoxification through perspiration.
Having a sauna room on private property is considered a luxury rather than a necessity.
Public saunas are segregated.
In Japan,
Many saunas exist at sports centers and public bathhouses.
The saunas are almost always gender separated,
Often required by law.
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 centos have added more features such as saunas in order to survive.
In Korea,
Saunas are essentially public bathhouses.
However,
It does not strictly refer to the original Fennoscandian steam rooms that have become popular throughout the world.
The Conglish word sauna usually refers to bathhouses with jacuzzis,
Hot tubs,
Showers,
Steam rooms and related facilities.
In Laos,
Herbal steam sauna is very popular,
Especially with women and is available in every village.
Many women apply yogurt or a paste blend based on tamarind on their skin as a beauty treatment.
The sauna is always heated by wood fire and herbs are added either directly to the boiling water or steam jet in the room.
The sitting lounge is mixed gender,
But the steam rooms are gender separated.
In Australia and Canada,
Saunas are found mainly in hotels,
Swimming pools and health clubs.
In Canada,
Saunas have increasingly become a fixture of cottage culture,
Which shares many similarities within its Finnish counterpart.
In Finland and Estonia,
A sauna session can be a social affair,
In which participants sit or recline in temperatures typically between 70 and 100 degrees Celsius.
This includes relaxation and promotes sweating.
People use a bundle of birch twigs with fresh leaves to slap the skin and create further stimulation of the pores.
A sauna is an important part of daily life,
And families bathe together in the home sauna.
There are at least 2 million saunas in Finland according to official registers.
The Finnish Sauna Society believes the number can actually be as high as 3.
2 million saunas.
Many Finns take at least one a week,
And much more when they visit their summer cottage in the countryside.
Here the pattern of life tends to revolve around the sauna and a nearby lake used for cooling off.
Sauna traditions in Estonia are almost identical to Finland,
As saunas have traditionally held a central role in the life of an individual.
Ancient Estonians 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.
The folk tradition related to the Estonian sauna is mostly identical to that surrounding the Finnish sauna.
On New Year's Eve,
A sauna would be held before midnight to cleanse the body and spirit for the upcoming year.
