Therapeutic Effects of Far Infrared Sauna Therapy

History of the Sauna and Development of Far Infrared Therapy as a glance:
The Finns first popularized sauna use in Europe. Their ancient religious ceremonies used it for mental, spiritual, and physical cleansing. Use of the sauna in their religion stayed with them when they migrated between 5,000 and 3,000 B.C. from an area northwest of Tibet to their present location in Finland. Similarly, Native Americans have used sweat lodges for cleansing and purifying since prehistoric times, recognizing the health benefits, as well.

Dr. Tadashi Ishikawa, a member of the Research and Development Department of Fuji Medical, received a patent in 1965 for a zirconium ceramic infrared heater used in the first healing infrared thermal systems. Medical practitioners in Japan were the only ones using infrared thermal systems for 14 years. In 1979, they were finally released for public use. The technique has been further refined into infrared thermal systems that have been sold in the United States since 1981. One use of infrared heat in the United States has been in the form of panels used in hospital nurseries to warm newborns.

Increases extensibility of collagen tissues
Tissues heated to 45 degrees Celsius and then stretched exhibit a non-elastic residual elongation of about 0.5 to 0.9 percent that persists after the stretch is removed. This effect does not occur in these same tissues when stretched at normal tissue temperatures. Therefore, 20 stretching sessions can produce a 10-18% increase in length of tissues heated and stretched. Stretching of tissue in the presence of heat would be especially valuable in working with ligaments, joint capsules, tendons, fasciae, and synovium that have become scarred, thickened, or contracted. Such stretching at 45 degrees Celsius causes much less weakening in stretched tissues for a given elongation than a similar elongation produces at normal tissue temperatures.

Experiments have clearly shown that low-force stretching could produce significant residual elongation when heat is applied together with stretching or range-of-motion exercises, which is much safer than stretching tissues at normal tissue temperatures.

Decreases joint stiffness
There is a 20% decrease in rheumatoid finger joint stiffness at 45 degrees Celsius (112 degrees Fahrenheit) as compared to 33 degrees Celsius (92 degrees Fahrenheit), which correlates perfectly to both subjective and objective observation of stiffness. Speculation has it that any stiffened joint and thickened connective tissues may respond in a similar fashion.

Relieves muscle spasm
Muscle spasms have long been observed to be reduced through the use of heat, be they secondary to underlying skeletal, joint, or neuropathological conditions. This result is possibly produced by the combined effect of heat on both primary and secondary afferent nerves from spindle cells and from its effects on Golgi tendon organs. Results produced demonstrate their peak effect within the therapeutic temperature range obtainable with radiant heat.

Leads to pain relief
Pain may be relieved via the reduction of attendant or secondary spasms. Pain is also at times related to ischemia (lack of blood supply) due to tension or spasm that can be improved by the hyperemia that heat-induced vasodilatation produces, thus breaking the feedback loop in which the ischemia leads to further spasm and then more pain.

Heat has been shown to reduce pain sensation by direct action on both free-nerve endings in tissues and on peripheral nerves. In one dental study, repeated heat applications led finally to abolishment of the whole nerve response responsible for pain arising from dental pulp.

Heat may lead to both increased endorphin production and a shutting down of the so-called "spinal gate" of Melzack and Wall, each of which can reduce pain.

Localized infrared therapy using lamps tuned to the 2-25 micron waveband is used for the treatment and relief of pain by over 40 reputable Chinese medical institutes.

International Reports on Far Infrared Therapy Use
Over the last 25 years, Japanese and Chinese researchers and clinicians have completed extensive research on infrared treatments and report many provocative findings. In Japan, there is an "infrared society" composed of medical doctors and physical therapists dedicated to further infrared research. Their findings support the health benefits of infrared therapy as a method of healing.

There have been over 700,000 infrared thermal systems sold in the Orient for whole-body treatments. An additional 30 million people have received localized infrared treatment in the Orient, Europe, and Australia with lamps, which emit the same 2-25 micron wave bands as employed in a whole-body system. In Germany, physicians in an independently developed form have used whole-body infrared therapy for over 80 years.

Increases blood flow
Heating one area of the body produces reflex-modulated vasodilators in distant-body areas, even in the absence of a change in core body temperature. Heat one extremity and the contralateral extremity also dilates; heat a forearm and both lower extremities dilate; heat the front of the trunk and the hand dilates.

Heating muscles produces an increased blood flow level similar to that seen during exercise. Temperature elevation also produces an increased blood flow and dilation directly in capillaries, arterioles, and venules, probably through direct action on their smooth muscles. The release of bradykinin, released as a consequence of sweat-gland activity, also produces increased blood flow and vasodilatation.

Whole-body hyperthermia, with a consequent core temperature elevation, further induces vasodilatation via a hypothalamic-induced decrease in sympathetic tone on the arteriovenous anastomoses. Axonal reflexes that change vasomotor balance also produce vasodilatation.

Assists in resolution of inflammatory infiltrates, edema, and exudates
Increased peripheral circulation provides the transport needed to help evacuate edema, which can help inflammation, decrease pain, and help speed healing.

Introduced in cancer therapy
More recently, infrared heat has been used in cancer therapy. This is a new experimental procedure that shows great promise in some cases when used properly. American researchers favor careful monitoring of the tumor temperature; whereas, the successes reported in Japan make no mention of such precaution.

Affects soft tissue injury
Infrared healing is now becoming a leading edge care for soft tissue injuries to promote both relief in chronic or intractable "permanent" cases, and accelerated healing in newer injuries.