air therapy, medical treatment in the open air. It is included with solar therapy and thalassotherapy as a part of climatic therapy. The goal of aerotherapy is to supply the body with oxygen and increase its resistance to the effects of changes of temperature in the external environment.

The energy expenditure of an adult person in the recumbent position who is fasting is about 70 joules per second (1 kilo-calorie per minute); this energy is supplied by the consumption of about 4 milliliters per second, or 5.6 milligrams per second, of oxygen from inhaled air. Under physical and mental stress oxygen consumption increases. In disturbances in the body’s exchange of gases, increased aeration and oxygenation acquire therapeutic value. Aerotherapy is especially beneficial when under natural conditions the air has a high oxygen content, is somewhat ionized, and contains beneficial admixtures of ions of elements found in seawater or admixtures of the products of floral vital activity, both of which stimulate breathing and other body functions. The principal forms of aerotherapy are air baths and prolonged stays on open or semiclosed verandas or in the open air in any weather, either clothed or abed. Aerotherapy and aero-prophylaxis are administered in various climatic zones in the countryside and at health resorts in the form of a prolonged outdoor period of rest—that is, repose, diurnal and nocturnal sleep under the open sky or on specially adapted verandas and climatic pavilions, and measured doses of walks, gymnastics, games, sports practice, work, and so on. Weather conditions and the patient’s endurance and state of health determine the length of his stay outdoors—that is, whether uninterrupted or at intervals, in clothing or abed, for one course of treatment or for an entire season or a year. The time outdoors is gradually increased from one or two hours up to 12–24 hours per day. Air baths—which may be “total baths” or “semibaths” (with the body bared to the waist)—are also prescribed, taking into account weather conditions and the patient’s state of health, and are sometimes recommended in combination with walks, exercise, and automassage. These are taken indoors or out, in tree-shaded places and under awnings or under a cloudy sky. Aerotherapy is combined with moist spongings, showers, bathing, and exposure to the sun. Aeroprophylaxis is administered in urban conditions as well, where walks may be taken on the street or in a park, and at home by regularly ventilating the living quarters and by staying in a room with open windows.

When air cooling is used in therapeutic or prophylactic aerotherapy, there must be no strong air currents; care must be taken to avoid overheating or chilling from the ground, stone floors, or walls. Air baths are prescribed with a gradual increase in duration: one to two minutes for cold baths (under 15°C), three to five minutes for cool baths (16–19°C), and ten to 15 minutes for warm baths (over 20°C). In case of unpleasant sensations or shivering, the duration of the air bath is shortened. Aerotherapy and air baths are used to correct irregularities in heat exchange and thermoregulation. Baring the body improves skin respiration and in hot weather expedites heat emission. In cold and cool weather, taking air baths and staying outdoors in clothing activates thermoregulation, increases oxygen saturation of the blood, improves the activities of the internal organs, and increases the body’s efficiency and resistance to the effects of temperature change, to colds, and to other illnesses. Thus, aerotherapy fosters the “tempering” of the body. When a person lives for a long time in conditions of insufficiently pure air with some decrease in oxygen content and with impaired thermoregulation from wearing heavy clothing and from remaining in warm, closed, rooms, aerotherapy acquires increased prophylactic value. Aerotherapy is contraindicated in acute inflammatory and febrile diseases and also in severe impairment of the body’s defense mechanisms.