Cryotherapy (Cryogenic chamber therapy) is a treatment whereby the patient is placed in a cryogenic chamber for a short duration, i.e. no more than three minutes, which is comparable to ice swimming, and if used properly, will not destroy tissue. The term "cryotherapy" comes from the Greek cryo (κρυο) meaning cold and the word therapy (θεραπεια) meaning cure.

Whole Body Cryotherapy initially originated in Japan in 1978. However, it was a group of Polish scientists who took the idea and made Whole Body Cryotherapy the physical therapy it is today. The Olympic rehabilitation centre in Spala, Poland opened in May 2000 and has been used as a training and injury rehabilitation centre for many sporting bodies.

The chamber is cooled, typically with liquid nitrogen, to a temperature of –110 C. The patient is protected from acute frostbite with socks, gloves and mouth and ear protection, but in addition to that, wears nothing but a bathing suit. The patients spends a few minutes in the chamber. During treatment the average skin temperature drops 12 C, while the coldest skin temperature can be 5 C. The core body temperature remains unchanged during the treatment, while after it, it may drop slightly. Curiously enough, some patients compare the feeling to sauna at +110 C. Release of endorphines occurs, resulting in analgesia (immediate pain relief).

Patients report the experience is invigorating and improves a variety of conditions. These include symptoms of psychological stress, insomnia, rheumatism, muscle and joint pain, fibromyalgia, itching, and psoriasis. The immediate effect of skin cooling and analgesia lasts for 5 minutes, but the release of endorphines can have a lasting effect, where the pains and signs of inflammation as found in blood tests remain suppressed for weeks. The effects of extreme cold and endorphine release are scientifically studied.

From http://en.wikipedia.org/wiki/Cryotherapy_(chamber_therapy)