The sauna uses heat to cause the dilation of skin pores and an immediate transpiration with a consequent increase in sweating.
The Finnish sauna with dry heat reaches 85/90 ° C temperature, humidity level of about 10-20% and brings the skin to reach 40/42 ° C (46 ° C is the threshold of pain), while thanks to sweating the internal body heat remains almost unchanged (variation between 0.5-1 ° C). That’s why it is advisable and healthy to take a sauna without clothes, which can otherwise prevent sweating and consequently increase the internal body temperature. In the first moments the liquid of sweating is mainly subtracted from the blood (therefore useful to stimulate peripheral blood circulation with friction and / or hot foot baths before entering the sauna), resulting in a drop in blood pressure and compensatory tachycardia and recall of fluid from other tissues until normalization. With sweating, one can lose up to one liter of fluids with electrolytes, lactic acid, amino acids, uric acid, sodium and potassium.
The Turkish bath with humid heat reaches a temperature of about 45°C with a relative humidity of about 90 – 95%. In this way it promotes blood and lymphatic circulation, also encouraging the expulsion of toxins through sweat. Thanks to the high level of humidity, it has a decongestant action on the respiratory tract and regularizes blood pressure.
The biosauna does not exceed 65°C but with a relative humidity between 40-50% it makes you sweat a lot and, alternating it with cold baths, it makes the capillaries and superficial veins constrict in a gentle way with a continuous succession of dilation and contraction, keeping them elastic and efficient.
The aufguss or steam jet causes a sudden increase in humidity with a consequent increase in the perception of heat that causes an additional thermal stimulus on the body and induces the sweat glands to work harder, removing more toxins with sweat.
The heat of the sauna doubles the speed of blood circulation in a very short time and also the work of all organs (the heart first and the kidneys). Therefore, do not drink alcohol either before or after the sauna, have a light meal and do not fast before the sauna. Drink plenty of liquids (non-carbonated water, juices, tea) before and after the sauna. Take a hot shower and dry off before entering. Do not wear jewelry that can cause burns or clothing that can cause heat stroke. The minimum time in the sauna to have benefit is 8 minutes. If possible, lie down, concentrate on your breathing, exit with slow movements, first sitting to compensate for the drop in pressure. Then cold shower and relax for 10/15 m ‘wrapped in a wool blanket to complete the cycle of sweating. Then repeat a second step.
By activating the lymphatic system, it increases immune defenses, preventing infections: flu, tonsillitis, colds, sinusitis, recurrent rhinitis (many viruses are thermolabile at temperatures of 40/50°C). It improves pollen allergies, hay fever. The warm air on the bronchi has a soothing and emollient effect, increasing blood circulation in the respiratory tract: therefore indicated in diseases of the respiratory tract and chronic bronchitis.
It favors the secretion of mucus and strengthens and relaxes the muscles of breathing, recommended in certain forms of asthma.
Indicated in chronic cases of all forms of rheumatism for the soothing effect of pain.
Attenuates premenstrual pains and regularizes the weak flow.
The skin gains elasticity, cellulite decreases, cures chronic skin diseases, furuncles, acne. The strong blood circulation and intense sweating induced by the heat prevents adipose stagnation and helps the decrease of cellulite and skin imperfections, produces a thorough cleaning of the skin (especially if through peeling). The dry heat does not damage the hair at all, on the contrary it purifies and irrigates the scalp.
It decreases up to two kilos, but only of liquids that must be replenished as soon as possible. It reduces LDL cholesterol with a reduction of the lipidic balance comparable to a modest/intense physical activity.
Improves the metabolism of all excretory organs (kidneys, liver, pancreas) thanks to the increase in blood circulation, and therefore increases the elimination of toxins, uric acid, metabolic waste, lactic acid. (indicated after intense physical efforts or sports activities). It determines a great benefit for diabetics, modulating the activity of the autonomic nervous system. In drug addicts, even after many years of abstention from drugs, residues are removed.
Relaxes the central nervous system and has a decontracting effect on the muscles (beneficial in case of stress and intense muscular effort with accumulation of lactic acid). It improves the body’s thermoregulatory system and the functioning of the sweat glands, improves the psycho-physical balance and raises the pain threshold and the ability to withstand environmental heat. It determines an improvement in mood and psychic well-being, especially if associated with pleasant music that triggers, like food, drugs or sex, the release of dopamine and activates the nerve centers responsible for satisfaction.
To understand the positive and negative effects of the sauna on the whole organism, we must understand the effect of this on the heart, because any environmental modification (stress, heat, cold, physical effort, etc.) affects the nutrition and oxygenation of all tissues and organs of the body. The heart is activated to maintain the homeostasis of all organs (brain, kidneys, liver, muscles, heart itself). Its function is to continuously circulate blood in adequate quantities and speeds in all organs, in order to bring them nourishment and oxygen and remove waste and carbon dioxide from them. Through the superficial venous circulation it also has a homeostatic function designed to keep the body temperature constant (below 37 ° C). The caloric shock of the sauna causes a generalized and sudden cutaneous vasodilation reaction that favors sweating and cooling of the body to keep the internal temperature constant: this causes acute and sudden loss of liquids with recall of liquids from other tissues and an increase in the peripheral vascular bed resulting in a fall in blood pressure (hypotension). To compensate for this, the heart increases the rate of the beat (up to double reaching 120 beats / m ‘), with a consequent increase in effort and consumption of oxygen and glucose. It is therefore clear that the heart is the first and fundamental organ to undergo the “sauna effect” in a positive and / or negative way. In a normal heart, the sauna strengthens and trains the heart itself, preventing possible heart disease. However, it also has numerous beneficial and therapeutic effects on numerous cardiac pathologies: it is recommended in previous myocardial infarctions, in ischemic pathologies after coronary stendt placement, in forms of spontaneous and non-drug-induced bradycardias, in chronic heart failure (training the heart and reducing circulating fluids), in arterial hypertension, in arterial hypotension.
The sauna is contraindicated in acute infections generally due to increased mucosal congestion (fever, colds, flu) and in respiratory ones in particular and in some cases of asthma (it can trigger a crisis), bronchitis. Contraindicated in forms of joint rheumatism and acute rheumatoid arthritis. It can temporarily aggravate dermopathies with skin redness (rosacea and eczema), venereal diseases, wounds not yet healed. Not recommended in acute neuromuscular inflammations, in the current menstrual cycle (due to vasodilation, reduction of blood viscosity and consequent haemorrhage). To be avoided in renal insufficiency due to excessive loss of fluids and electrolytes. Contraindicated in neurological pathologies such as epilepsy, recent neurosurgical interventions, in children under the age of 5 for failure to complete the development of the thermoregulatory and lymphatic system. The high temperature of the sauna can deform contact lenses, conjunctival inflammation and glaucoma can worsen. Contraindicated in pregnancy (even small changes in the mother’s body temperature can cause harm to the unborn child.) Inhaled and smeared oils can cause allergic skin and respiratory reactions, skin and conjunctival irritation. Contraindicated in claustrophobics. It can cause “heat stroke” if you take saunas covered with clothes, with a noticeable increase in heart rate and core temperature, sickness, stomach pain and lightheadedness. The sudden drop in blood pressure can cause lipothymia with temporary loss of consciousness, slow heart rate, risk of trauma from falling. (accentuated by the passages from lying or sitting to standing quickly). Avoid entering the sauna on an empty stomach or after large meals.
In the sauna you can contract fungal diseases of the feet and / or nails, legionella is rare.
The sauna is contraindicated in acute heart failure or decompensation due to a sudden increase in effort and oxygen consumption, degenerative heart disease, inflammatory heart disease (pericarditis, myocarditis), carriers of some types of PM who are unable to adapt to the increased heart rate required , III ° valvulopathies, AV block or total, cardiogenic shock and recent AMI, atrial flutter or fibrillation, ventricular tachycardia, vagal hypotension, chronic hypokalaemia with risk of cardiovascular arrest.
The sauna, if done according to the correct criteria, is healthy and therapeutic (called the pharmacy for the poor), avoiding wearing clothing that limits perspiration, avoiding being fast or too full, drinking lots of fluids, making slow movements and getting ready before and later, respecting the recommended rules.