by Dr. Aaron M. Flickstein
“Regular use of a sauna may impact a similar stress on the cardiovascular system as running, and its regular use may be as effective [at] burning calories.”
– Journal of the American Medical Association
• The Use of Infrared Heat to Produce Cardiovascular Conditioning
• History of the Sauna and Development of Infrared Technology
• World-Wide Reports on Infrared Sauna Use
• Musculoskeletal Improvements with Infrared Heat
• Effects of Infrared Heat on Rheumatoid Arthritis
• Other Therapeutic Effects of Infrared Heat
1. Infrared heat increases the extensibility of collagen tissues.
2. Infrared heat decreases joint stiffness
3. Infrared heat relieves muscle spasms.
4. Infrared heat treatment leads to pain relief.
5. Infrared heat increases blood flow.
6. Infrared heat assists in resolution of inflammatory infiltrates, edema, and exudates.
7. Infrared heat introduced in cancer therapy.
8. Infrared heat affects soft tissue injury.
• Chinese Studies Report Positive Effects of Infrared Heat
• Japanese Studies on the Positive Effects of Infrared Heat
• Speculation about Infrared Heat Effects on Blood Circulation
• Infrared Heat and Coronary Artery Disease, Arteriosclerosis, and Hypertension
• Aging and Infrared Heat Therapy
• Ear, Nose, and Throat Conditions Relieved with Infrared Heat
The Use of Infrared Heat to Produce Cardiovascular Conditioning
The August 7, 1981 issue of the Journal of the American Medical Association (JAMA) reported what is common knowledge today: Many people who run do so to place a demand on their cardiovascular system as well as to build muscle. What isn’t well known is that it also reported the “regular use of a sauna may impart a similar stress on the cardiovascular system, and its regular use may be as effective as a means of cardiovascular conditioning and burning of calories as regular exercise.”
It has been found that the infrared sauna makes it possible for people in wheelchairs, those who are otherwise unable to exert themselves, and those who won’t follow an exercising/conditioning program to achieve a cardiovascular training effect. It also allows for more variety in any ongoing training program.
Blood flow during whole-body hyperthermia is reported to rise from a normal five to seven quarts a minute to as many as 13 quarts a minute.
Due to the deep penetration of infrared rays (over one and a half inches into body tissue), there is a deep heating effect in the muscle tissue and internal organs. The body responds to this heat with a hypothalamic-induced increase in both heart volume and rate. Beneficial heart stress leads to a sought-after cardiovascular training and conditioning effect. Medical research confirms the use of a sauna provides cardiovascular conditioning as the body works to cool itself and involves substantial increases in heart rate, cardiac output, and metabolic rate. As a confirmation of the validity of this form of cardiovascular conditioning, extensive research by NASA in the early 1980’s led to the conclusion that infrared stimulation of cardiovascular function would be the ideal way to maintain cardiovascular conditioning in American astronauts during long space flights.
Infrared Heat, Caloric Consumption, and Weight Control In its Wellness Letter, October 1990, the University of California Berkeley reported that “the 1980’s were the decade of high-impact aerobics classes and high-mileage training. Yet there was something elitist about the way exercise was prescribed: only strenuous workouts would do, you had to raise your heart rate to between X and Y, and the only way to go was to “go for the burn.” Such strictures insured that most ‘real’ exercisers were relatively young and in good shape to begin with. Many Americans got caught up in the fitness boom, but probably just as many fell by the wayside. As we’ve reported, recent research shows that you don’t have to run marathons to become fit – that burning just 1,000 calories a week…is enough. Anything goes, as long as it burns these calories.”
Guyton’s Textbook of Medical Physiology reports that producing one gram of sweat requires 0.586 kcal. The JAMA citation above goes on to state that “A moderately conditioned person can easily sweat off 500 grams in a sauna, consuming nearly 300 kcal – the equivalent of running two to three miles. A heat-conditioned person can easily sweat off 600 to 800 kcal with no adverse effect. While the weight of water loss can be regained by rehydration, the calories consumed will not be.” Since a sauna helps generate two to three times the sweat produced in a conventional hot-air sauna, the implications for increased caloric consumption are quite impressive.
Assuming one takes a sauna for 30 minutes, some interesting comparisons can be drawn. Two of the highest calorie output exercises are rowing and running marathons. Peak output on a rowing machine or during a marathon burns about 600 calories in 30 minutes. An infrared sauna may better this from “just slightly”
up to 250 percent by burning 900 to 2400 calories in the same period of time. It might in a single session simulate the consumption of energy equal to that expended in a six- to nine-mile run.
The infrared sauna can therefore, play a pivotal role in both weight control and cardiovascular conditioning. It is valuable for those who don’t exercise and those who can’t exercise and want an effective weight control and fitness maintenance program, and the benefits regular exercise contribute to such a program.
History of the Sauna and Development of Infrared Technology
The Finns popularized sauna use. 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 BC from an area northwest of Tibet to their present location in Finland. Native American Indians used sweat lodges for cleansing and purifying, recognizing the health benefits of a sweat as well.
Dr. Tadashi Ishikawa, a member of the Research and Development Department of Fuji Medical, received a patent in 1965 for a zirconia 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.
World-Wide Reports on Infrared Sauna 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 to 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.
Musculoskeletal Improvements with Infrared Heat
Success has been reported from infrared treatments by Japanese researchers for the following musculoskeletal conditions:
Effects of Infrared Heat on Rheumatoid Arthritis
A case study reported in Sweden worked with a 70-year-old man who had rheumatoid arthritis secondary to acute rheumatic fever. He had reached his toxic limit of gold injections and his Erythrocyte Sedimentation Rate (ESR) was
still 125. After using an infrared heat system for less than five months, his ESR was down to 11.
The rheumatologist worked with a 14-year-old Swedish girl who had difficulty walking downstairs due to knee pain from the age of eight. This therapist told her mother the girl would be in a wheelchair within two years if she didn’t begin gold corticosteroid therapy. After three infrared sauna treatments, she began to become more agile and subsequently took up folk dancing without the aid of conventional approaches in her recovery.
A clinical trial in Japan reported a successful solution for seven out of seven cases of rheumatoid arthritis treated with whole-body infrared therapy.
These case studies and clinical trials indicate that further study is warranted for the use of whole-body infrared therapy in the care of patients with rheumatoid arthritis.
Other Therapeutic Effects of Infrared Heat
The following information has been summarized from Chapter 9 of Therapeutic Heat and Cold, Fourth Edition, Editors Justus F. Lehmann, M.D., Williams, and Wilkin, or concluded from data gathered there.
Generally it is accepted that heat produces the following desirable therapeutic effects:
- Infrared heat increases the 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 does not occur in these same tissues when stretched at normal tissue temperatures. Therefore 20stretching sessions can produce a 10 to 18 percentage 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 synoviurn that have become scarred, thickened, or contracted. Such stretching at 45 degrees Celsius caused much less weakening in stretched tissues for a given elongation than a similar elongation produced at normal tissue temperatures.
Experiments cited clearly showed low-force stretching could produce significant residual elongation when heat is applied together with stretching or range-of-motion exercises. This is safer than stretching tissues at normal tissue temperatures.
- Infrared heat decreases joint stiffness. There was a 20 percent decrease in rheumatoid finger joint stiffness at 45 degrees Celsius (112 degrees Fahrenheit) as compared with 33 degrees Celsius (92 degrees Fahrenheit), which correlated 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.