Almost every gym in America has a sauna or steam room, but they’re usually neglected as we sprint past them for the treadmill and weight room. To most of us, a stint in the sauna may seem an indulgent treat, like a festive holiday beverage, rather a necessary part of our wellness routine.
But the opposite is true in other cultures where the benefits of sauna time are considered vital to health. In Finland, sauna tradition dates back to the 12th century, and the country is still crazy about saunas: Finland boasts approximately one sauna for every three people, and 99 percent of Finns sauna it up at least once per week! A bunch of other cultures have their own versions: the Turkish hammam, Russian banya, and Korean Hanjeungmak, to name a few. While each has a unique take on the hot and/or steamy room concept, all emphasize its cleansing and healing properties. Could these cultures be on to something?
Breaking a Sweat
“Sauna” and “steam room” tend to be used interchangeably in the U.S., but there are a few differences between the two. A sauna gets super hot—between 160 to 200 degrees Fahrenheit—and has low humidity, while a steam room runs at a more reasonable 110 to 120 degrees. Steam rooms, as the name implies, also have much higher humidity.
While a hard workout can leave us dripping wet, saunas and steam baths provoke the same physical response without the effort. During exercise, body temperature rises and a response system kicks in to avoid overheating. Circulation picks up, blood flow goes to the skin, and sweat pours out—all in the name of keeping us cool Temperature regulation during exercise. Gleeson, M. International Journal of Sports Medicine, 1998; 19 Suppl 2:S96-9.. During a short sit in a sauna, the average individual’s pulse will rise by 30 percent as blood flow goes to cool the skin. As the circulatory system kicks into gear, one can sweat out about a pint of fluid in less than 20 minutes.
Rumor Has It...
A number of popular claims exist regarding the health benefits of steam rooms and saunas, but many lack strong scientific backing. Sweating has traditionally been regarded as a cleansing practice that offers numerous health benefits Environmental determinants of chronic disease and medical approaches: Recognition, avoidance, supportive therapy, and detoxification. Sears, M. E., & Genuis, S. J. Journal of Environmental and Public Health, 2012; 2012:356798., and sauna devotees claim that getting all hot and bothered can detoxify the body. However, this claim belongs in the category of juice cleanses. While certain environmental contaminants can make their way into body tissues, sweat plays a very minor role in taking out the trash. The body’s detoxification system relies on the kidney, liver, and lungs to get rid of all of the junk.
Weight loss is another draw for sauna-goers. Although some calorie-burning claims exist, they’re likely exaggerated. Some research shows that exercising in the heat may boost metabolism by a small amount—but probably too small to cause a big boost in caloric burn Effect of temperature on muscle metabolism during submaximal exercise in humans. Starkie, R. L., Hargreaves, M., Lambert, D. L. et al. Experimental Physiology, 1999; 84:775-784.. Likewise, simply sitting and sweating is unlikely to burn more than a couple of extra calories. The scale will certainly show a slight drop because losing water easily shaves off a few pounds. However, fat and muscle won’t budge no matter how high you crank the heat, which means the weight loss is only temporary, and with that sweat-induced weight loss, dehydration can be a risk. Bottom line: If you shaved off a few digits on the scale with sauna time, it’ll just return once you rehydrate.
Although sweating it out in a hot room isn’t the magic bullet for weight loss or squeaky-clean insides, sauna therapy may offer some real benefits to both healthy people and those with chronic disease such as hypertension, diabetes, and heart failure Beneficial effects of sauna bathing for heart failure patients. Blum, N., & Blum, A. Experimental and Clinical Cardiology, 2007; 12:29-32..
A few recent studies suggest that regular sauna therapy may strengthen vascular function, lower blood pressure, and improve insulin sensitivity Regular thermal therapy may promote insulin sensitivity while boosting expression of endothelial nitric oxide synthase--effects comparable to those of exercise training. McCarty, M. F., Barroso-Aranda, J., & Contreras, F. Medical Hypotheses, 2009; 73:103-105. Beneficial effects of sauna bathing for heart failure patients. Blum, N., & Blum, A. Experimental and Clinical Cardiology, 2007; 12:29-32.. However, the science on this topic is pretty new, so anyone with chronic disease should be sure to talk to a doctor before adding this to his or her treatment plan.
Those of us without chronic disease can also benefit from sweating it out. Several studies with healthy young men and women as subjects demonstrated a decrease in LDL cholesterol (the “bad” cholesterol) and in total cholesterol after several weeks of sauna bathing The effect of sauna bathing on lipid profile in young, physically active, male subjects. Gryka, D., Pilch, W., Szarek, M. et al. International Journal of Occupational Medicine and Environmental Health, 2014; 27:608-618. Changes in the lipid profile of blood serum in women taking sauna baths of various duration. Pilch, W., Szygula, Z., Klimek, A. T. et al. International Journal of Occupational Medicine and Environmental Health, 2010; 23:167-174.. Although these studies were very small and more research is needed, the findings are impressive.
And here’s more good news for sauna lovers: There’s some scientific evidence indicating that regular sauna sessions enhance athletic performance. One small study found that three weeks of post-exercise sauna time increased athletes’ endurance capacity, likely by increasing blood volume Effect of post-exercise sauna bathing on the endurance performance of competitive male runners. Scoon, G. S., Hopkins, W. G., Mayhew, S. et al. Journal of Science and Medicine in Sport / Sports Medicine Australia, 2007; 10:259-262.. Other research shows that a 30-minute sauna boosts strength and power in healthy young men, though unfortunately it appears to decrease muscular endurance The effects of acute heat exposure on muscular strength, muscular endurance, and muscular power in the euhydrated athlete. Hedley, A. M., Climstein, M., & Hansen, R. Journal of Strength and Conditioning Research / National Strength & Conditioning Association, 2002; 16:353-358.. And finally, after a hard workout, it could pay to hit up the steam room, as a heated mist bath (similar to a steam room) may accelerate muscle recovery Physiological functions of the effects of the different bathing method on recovery from local muscle fatigue. Lee, S., Ishibashi, S., Shimomura, Y. et al. Journal of Physiological Anthropology, 2012; 31:26-6805-31-26..
Even if lowering cholesterol or post-workout recovery are not on the agenda, we could all use a little R & R. Ample anecdotal evidence (and first hand “research” by the present writer) supports the claim that saunas and steam baths offer a great way to relax and reduce stress. Since “relaxation” is pretty subjective, there’s not a whole lot of strong science on the subject. However, one research study found that in depressed patients, sauna use led to higher levels of relaxation and reduction of other mental symptoms Repeated thermal therapy diminishes appetite loss and subjective complaints in mildly depressed patients. Masuda, A., Nakazato, M., Kihara, T. et al. Psychosomatic Medicine, 2005; 67:643-647..
Those in search of a detox or weight-loss magic bullet, look elsewhere. But for people looking to improve heart health, boost athletic performance and recovery, or just relax, a sauna or steam room might be worth checking out. Research is still limited and lots more needs to be done, but sweating it out (without the workout) appears to be safe and beneficial for most people as long as they follow a few guidelines:
• Skip the booze before and after
• Keep it to 15 to 20 minutes
• Hydrate before and after (a couple of glasses of water should do the trick)
• Head for the door if you start to feel sick or dizzy