Perkataan sauna berasal daripada Finland kuno yang bermaksud mandi tradisional Finland yang juga merujuk kepada bilik mandian itu sendiri.
Sauna tertua yang diketahui merupakan satu lubang yang digali diatas tanah yang digunakan sebagai tempat berdiam semasa musim salji. Didalam sauna batu-batu dipanaskan pada suhu yang tinggi. Air kemudian dicurahkan keatas batu-batu yang panas untuk menghasilkan wap panas dan meningkatkan haba.
Akibat daripada revolusi industri yang melanda Eropah, sauna mula berubah kepada penggunaan dapur kayu yang dibina lengkap dengan serombong asap.
Wap panas dan haba yang tinggi menyebabkan orang yang berdiam didalamnya berpeluh.
Orang-orang Finland juga menggunakan sauna sebagai tempat untuk menenangkan minda, meremaja dan menyegarkan semangat. Sauna merupakan sesuatu yang penting didalam kehidupan seharian mereka, dan ahli keluarga mandi wap bersama-sama didalam sauna rumah. Kadang-kadang wanita Finland melahirkan anak didalam sauna.
Bila orang-orang Finland berhijrah ketempat lain didunia ini, mereka membawa bersama mereka rekaan sauna dan budaya bersauna, membolehkan bangsa lain turut menikmati keseronokan dan manfaat kesihatan bersauna. Kini ada bermacam-macam jenis sauna termasuk bilik sauna elektrik dan sauna far infrared, yang semakin popular dalam dekad kebelakangan ini.
[Tajuk-tajuk seterusnya ditulis dalam Bahasa Inggeris - harap maaf]
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 sympathetic (action) and the parasympathetic (relaxation) nervous tone. 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.
Health Risks & Benefits
Saunas can also be dangerous due to the risk of heat prostration or the even more serious hyperthermia. 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 individuals 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 of alcoholic beverages, and also sauna bathing during alcohol withdrawal (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.
Sauna may provide some relief to patients with asthma and chronic bronchitis, and may also alleviate pain and improve joint mobility in patients with rheumatic disease. The sauna does not cause drying of the skin, and may even benefit patients with psoriasis, although sweating may increase itching in patients with atopic dermatitis.
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 even young 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 beta endorphin. However it also causes a substantial rise in the stress hormones ACTH (adrenocorticotropic hormone), and cortisol due to hyperthermic stress on the body. Cortisol remains high even after 30 minutes of rest. Sauna also found to reduce prostaglandin F2alpha and 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 estrogen. 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 parasympathetic system governs sweat glands secretion and is increased by sauna. It has been shown with drugs such as caffeine, that delayed metabolic (organ) clearance was offset by a minor (2.5 percent) 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. The beneficial effects of therapeutic sauna are both temporary and long term, with some benefits lasting about 24 hours. Adaptation and detoxification will occur after longer use when the practice can be suspended or continued if beneficial.