Sauna Health Benefit:
Medical practitioners often use infrared saunas to treat sprains, bursitis, peripheral vascular diseases, arthritis, and muscle pain, according to the McGraw/Hill Encyclopedia of Science & Technology.
Therapeutic Effects of Infrared Treatment
The following is summarized from Therapeutic Heat and Cold, 4th Edition by ED. Justus F. Lehmann M.D., Williams, and Wilkins, Chapter 9 or concluded from the data therein. Generally, it is accepted that heat produces the following desirable therapeutic effects:
1. It increases the flexibility of collagen tissues.
Tissues heated to 45ºC and then stretched exhibit a non-elastic residual elongation of about 0.5-0.9% that persists after the stretch is released, which does not occur in these same tissues when stretched at normal tissue temperatures. Thus 20 stretching sessions can produce a 10-18% increase in length in tissues so heated and stretched.
This effect would be especially valuable in working with ligaments, joint capsules, tendons, and fasciae that have become scarred, thickened, or contracted.
Such stretching at 45ºC caused much less weakening in stretched tissues than a similar elongation produced at normal tissue temperatures.
The experiments cited clearly showed that low-force stretching can produce significant residual elongation when heat is applied together with stretching or range-of-motion exercises, which is also safer than stretching tissues at normal tissue temperatures.
This safer stretching effect is crucial for properly training competitive athletes to minimize their "down" time from injuries.
2. It decreases joint stiffness directly.
There was a 20% decrease in stiffness at 45ºC as compared with 33ºC in rheumatoid finger joints, which correlated perfectly to both subjective and objective observation of stiffness.
Any stiffened joint and thickened connective tissues should respond in a similar fashion.
3. It relieves muscle spasms.
Muscle spasms have long been observed to be reduced through the use of heat, whether they’re due to skeletal, joint, or neurological conditions.
This result is possibly produced by the combined effect of heat on both primary and secondary afferents from spindle cells and from its effects on Golgi tendon organs. The effects produced by each of these mechanisms demonstrated their peak effect within the therapeutic temperature range obtainable with radiant heat.
4. It brings pain relief.
Pain may be relieved via the reduction of attendant or secondary muscle spasms.
Pain is also at times related to ischemia due to tension or spasm which can be improved by the hyperemia that heat-induced vasodilation 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 to the blocking of sensation to the nerve responsible for pain arising from dental pulp.
Heat may both lead to increased endorphin production and a shutting down of the so-called "spinal gate" as coined by Mel Zach and Wall, each of which can reduce pain.
5. It increases blood flow.
Heating of the area of the body produces reflex-modulated vasodilation in distant-body areas, even in the absence of a change in core body temperature; i.e. 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 the muscles produces an increased blood flow similar to that seen during exercise. Temperature elevation produces an increase in blood flow and dilation directly in capillaries and arterioles 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 vasodilation.
Whole-body hypothermia, with a consequent core temperature elevation, further induces vasodilation via a hypothalamic-induced decrease in sympathetic tone. Vasodilation is also produced by axonal reflexes and reflexes that change the vasomotor balance.
6. It assists in the resolution of inflammatory infiltrates, edema, and exudates.
The increased peripheral circulation provides the transport needed to help evacuate the edema which can help end inflammation, decrease pain, and help speed healing.
Success with musculoskeletal cases reported with infrared treatments by medical researchers:
- TMJ Arthritis
- Brain Contusion – accelerated healing
- Spinal Cord Shock – post-traumatic shock reversed
- Shoulder Pain – relieved or eliminated
- Muscle Spasms – reduced or eliminated
- Compression Fracture – pain stopped for 3 days with only a single treatment
- Post-Exercise Muscle Pain – vital to competitive athletes
- Arthritis: Gouty, Rheumatoid, DJD – each substantially relieved or improved
- Adhesions – lengthened or more easily broken; they are common in competitive athletes, trauma and repetitive stress syndromes
- Traumatic Arthritis
- Disc-protrusion Related Neuralgia
- Tight Shoulders – relaxed
- Muscle Tension – relaxed
- Bursitis – eliminated
- Low Back Pain – relieved
Additional Conditions Treated by Infrared Heat
Dr. Rubin P. Lysiak, M.D., of the O&P Medical Clinic, has reported great success with the use of infrared treatment for:
- Gastroenteric Problems
- Ear Diseases
- Shoulder Stiffness