Following a tough workout, many individuals choose to relax in a sauna or steam room.
Others choose to spend some time in a hot box as a means to unwind and re-center themselves amidst the chaos that can be daily life.
Saunas are also experiencing a surge in usage amongst massage clinics, physical therapy offices, health spas, beauty salons, and even the homes of biohackers looking to take advantage of the benefits of heat stress.
Today, we discuss the potential benefits of using a sauna or steam room as well as the differences between saunas and steam rooms.
What is a Sauna?
Saunas are small rooms or small buildings that are heated to temperatures between 150-195°F (65-90°C).
The inside of a sauna usually contains wooden benches along with an unpainted wood interior, in addition to temperature controls to regulate how hot you make the room.
Historically, saunas were heated by burning wood, a practice that is still used in rural parts of Finland today.
Modern saunas, like the kind you may find in your gym, are typically heated by a rock-filled electric heater, which creates heat and maintains the hot atmosphere. Water can be poured onto these rocks to generate steam and increase humidity in the sauna.
Today’s saunas can also be heated via infrared heaters.
Infrared saunas usually operate at slightly lower temperatures than traditional saunas (113°F to 140°F). <1>
Infrared heaters emit two types of wavelengths -- near or far-infrared wavelengths.
Near-infrared wavelength heaters use incandescent bulbs to produce thermal radiation of varying wavelengths, ranging from near-infrared to middle-infrared wavelengths.
Far infrared wavelength heaters use ceramic or metallic heating elements that radiate energy in the far-infrared range, similar to the type of energy produced by the sun.
As we mentioned above, saunas can be either dry or hot.
Saunas used in Finland typically use dry heat, while Turkish-style saunas (hammam) use a higher moisture environment, more akin to the modern steam room.
Other examples of saunas used throughout history include the Russian banya, which is traditionally more humid than a Finnish sauna. <2>
While Turkish saunas are typically assumed to be more humid, the original model was dry, modeled in the fashion of the Roman thermae. <2>
Now, you might wonder if there’s any difference between being in a dry heat or moist (humid) heat.
Well, moisture conducts heat to the skin more effectively than dry air (via the release of latent thermal energy). <2>
This is why steam rooms may feel “hotter” or “as hot” as dry saunas, even though the temperature in a steam room is typically lower than a sauna, which brings us to our next topic of conversation...
Sauna vs. Steam Room -- What's the Difference?
On the surface, both saunas and steam rooms seem quite similar.
At their core, they both are (relatively speaking) small, heated spaces where you sit and "relax" for a specified period.
However, when you start to dig into the specifics, you’ll realize there are some significant differences between saunas and steam rooms.
For starters, the method used to heat each room is different.
Traditionally, saunas use dry heat, created using a closed stove or rock-filled electric heater.
Steam rooms are usually heated by a generator filled with boiling water that spews hot steam into the air.
(Note: As we mentioned above, not all saunas are “dry.” Turkish-style saunas use higher moisture environments compared to saunas done in the Finnish fashion.)
This difference in heating brings us to the next significant difference between saunas and steam rooms.
Steam rooms are usually significantly more humid than saunas.
This increase in moisture content may feel (subjectively) hotter compared to a dry sauna due to a decrease in the amount of evaporative cooling that can take place. Further, these wet environments may also be harder on the cardiovascular system. <3>
As we mentioned above, saunas also tend to be heated to a higher temperature than steam rooms.
On average, saunas are heated to temperatures between 150-195°F (65-90°C) while steam rooms are heated to temperatures between 100 and 120°F.
But, the significantly higher humidity of steam rooms makes them feel as hot (or hotter) than saunas.
Anyone that’s spent time in a very “wet heat” (a la New Orleans) will attest that it’s just as hot (perceptually) as very dry heat environments (Austin, Las Vegas, etc.).
Now, let’s delve into what happens within the body while you’re sweating inside the hot box.
What Happens to the Body During Sauna?
Given the popularity of “sweat bathing” in recent years, researchers have started to take a keener interest in how heat stress affects the human body (as well as what benefits may be derived from exposure to it).
Some of the claimed health benefits from saunas and steam rooms include:
- Increased Metabolism
- Detoxification
- Weight Loss
- Anti-aging
- Increased Circulation
- Pain Reduction
- Improved Cardiovascular Function
- Skin Rejuvenation
We'll address the potential benefits of sauna bathing in a moment, but first, let's discuss how exposure to heat stress ("sauna bathing") may affect human physiology.
To date, researchers have proposed several mechanisms by which sauna bathing may confer health effects.
Research notes that exposure to heat increases cardiac output and reduces peripheral vascular resistance. <4,5,6,7,8>
It also has been noted to help decrease systolic and/or diastolic blood pressure, increase heart rate variability (HRV), boost cardiac function, enhance vasodilation, and improve flow-mediated dilatation. <9,10>
Additionally, studies show that short-term heat exposure increases skin temperature and core body temperature.
It also activates specific thermoregulatory pathways via the hypothalamus and central nervous system (CNS), which subsequently activate the autonomic nervous system.< 11>
Activation of the sympathetic nervous system and, as a result, the hypothalamus-pituitary-adrenal (HPA) axis and the renin-angiotensin-aldosterone system, leads to increased cardiac output, heart rate, and skin blood flow. <12,13>
Research also indicates that sauna bathing may increase sweating, which may help eliminate various industrial toxicants from the body, such as heavy metals, pesticides, and other petrochemicals. <14>
At the cellular level, exposure to heat stress (both wet and dry forms) induces notable changes in the <14>:
- Increase in nitric oxide availability
- Decrease of reactive oxygen species (ROS)
- Production of heat shock proteins
- Reduced oxidative stress and inflammation pathway activities
- Enhanced insulin sensitivity
- Positive changes in specific endothelial-dependent vasodilatation pathways
A recent systematic review of saunas also noted that <14>:
“The mechanisms for these effects may include increased bioavailability of NO (nitric oxide) to vascular endothelium, heat shock protein-mediated metabolic activation, immune and hormonal pathway alterations, enhanced excretions of toxicants through increased sweating, and other hormetic stress responses.”
Up next, let’s see how these changes may lead to benefits for those of you interested in trying a sauna bath.
Benefits of Using a Sauna
Cardiovascular Health
Rigid, inflexible blood vessels are a primary indicator of cardiovascular disease (CVD).
By extension, anything that increases nitric oxide production encourages more flexible vasculature (blood vessels) and promotes higher blood flow is typically viewed as beneficial for cardiovascular health.
Research indicates that spending some time in a sauna may benefit the cardiovascular system via its ability to improve vasodilation (the ability of blood vessels to dilate). This encourages greater blood flow and a (beneficial) reduction in blood pressure (since a significant portion of the population suffers from high blood pressure -- hypertension). <17,18>
You see, when you sit in a sauna, skin temperature rapidly increases, and within minutes of entering, you begin sweating.
This is a protective measure by the body as it functions to help keep core temperature within a safe range.
Additionally, heart rate and blood flow increase while blood pressure decreases to accommodate the rise in circulation.
Research demonstrates that heart rate may increase between 100-150 beats per minute (BPM) during sauna bathing sessions (depending on the intensity of the heat environment used), which is similar to increases in heart rate observed during moderate- to vigorous-intensity physical exercise. <16>
Furthermore, the increased skin blood flow that occurs during sauna bathing may also improve vascular function.
Additional research suggests that saunas may reduce oxidative stress in the body, which may provide yet another avenue by which sauna bathing can reduce heart disease and other inflammatory disorders. <14>
May Help Relieve Pain
While many individuals choose to sit in the sauna as a way to relax, others find it helpful for ridding the body of aches and pains.
Research in individuals with chronic musculoskeletal disorders, including rheumatoid arthritis (RA) and ankylosing spondylitis, found that 4-weeks of sauna sessions decreased feelings of pain, stiffness, and fatigue. <19>
May Improve Feelings of Well-being
Stress is a regular occurrence of everyday life.
Yet, despite our best efforts to keep stress levels under control, it gets the better of us far too often.
Left unchecked, chronic stress leads to sustained elevations in cortisol -- the primary “stress hormone” in the body.
The adverse effects of chronically elevated cortisol levels are well known, including <20>:
- Difficulty Sleeping
- Impaired Immune Function
- Reduced Cognitive Function
- Poor Mood
- Promotes Cancer Development
A 4-week study investigating the effects of sauna bathing noted improvements in relaxation scores in 28 patients diagnosed with mild depression.< 14>
Promotes Brain Health
Cognitive decline is caused by a multitude of factors, including:
- Impaired Cardiovascular Function,
- Inflammation
- Oxidative Stress
- Aging
Recent research suggests that regular “dips” in the sauna may exert neuroprotective effects. <22>
A prospective cohort study involving 2,315 Finnish men (aged 42 to 60) found that men who took 4-7 sauna sessions/week compared to men who only used the sauna one time per week had a 66% and 65% reduced risk of dementia and Alzheimer disease, respectively. <22>
Research also shows that exposure to heat stress as well as exercise increases the expression of brain-derived neurotrophic factor (BDNF), a protein in the brain that supports the growth of new neurons and maintenance of existing ones. <21>
More research is needed to fully elucidate the mechanism(s) by which sauna bathing may confer cognitive benefits, but the preliminary evidence is encouraging.
Additional Benefits
Researchers continue to investigate the many potential benefits of regular sauna bathing. A few other preliminary findings that have been attributed to sauna bathing, include<17>:
- Reduced occurrence and intensity of headaches
- Decreased symptoms associated with psoriasis
- Improved health-related quality of life
- Lower risk of vascular diseases such as high blood pressure, cardiovascular disease (CVD), and stroke
- Improved cholesterol profile
Supplements to Enhance Sauna Benefits
Sitting for any meaningful length of time in a sauna is sure to have you sweating. Still, if you're looking to intensify your experience, SteelFit® offers several thermogenic pre-workouts and supplements the complement your time spent sweating it out. We also have curated stacks to help you tighten and tone.
Steel Sweat®
Steel Sweat® is a thermogenic powder formulated to enhance calorie burning, energy expenditure, and perspiration. It serves as a great low-stim option for cardio workouts, or as a delicious mid-day pick me up to get you through the afternoon.
In addition to supplying prominent thermogenic supplements such as Paradoxine®, CapsiAtra®, and GBBGO®, Steel Sweat® also provides essential electrolytes, including potassium and sodium, to support hydration.
Shredded Steel®
Shredded Steel® is a stimulant-powered thermogenic capsule supplying quality doses of research-backed supplements that support fat burning and weight loss, including caffeine, Paradoxine®, KSM-66®, and Yohimbine.
Steel Core®
Steel Core® is a stimulant-free thermogenic weight loss aid that supports increased energy expenditure and fat burning from multiple directions. Notable thermogenic features of Steel Core® include 40mg Paradoxine® and 3mg CapsiAtra®. Steel Core® also contains Morosil® (Sicilian Red Orange Fruit Extract) and Alpha Lipoic Acid (ALA) for their antioxidant benefits, which help combat oxidative stress and inflammation.
Takeaway
Saunas provide another means for relaxing and unplugging from our hectic lives. Beyond its stress-relieving properties, regular sauna bathing may also help lower stress and improve several markers of cardiovascular health.
A 2018 systematic review concluded that <14>:
"Regular infrared and/or Finnish sauna bathing has the potential to provide many beneficial health effects, especially for those with a cardiovascular-related and rheumatological disease, as well as athletes seeking improved exercise performance."
Finally, make sure you properly hydrate before and after using the sauna due to the immense amount of fluids and electrolytes lost as a result of sweating. To help replenish minerals and electrolytes lost during sauna bathing, we like to drink a serving of Steel Fuel®.
Steel Fuel® is a delicious-tasting amino acid + hydration supplement providing essential minerals (including sodium, magnesium, and potassium) along with 5 grams of 2:1:1 BCAAs to support hydration, muscle repair, and protein synthesis.
*Disclaimer: The Institute of Medicine recommends a daily water intake of 3 liters or more for active individuals. Sweating increases this recommendation. Consuming inadequate amounts of water increases the risk of dehydration, kidney stones, poorer cognitive and physical performance, dangerous cramping and electrolyte imbalances. Always consult a licensed physician before taking any supplements or starting a new workout regimen.
References
- Beever, R. Far-infrared saunas for treatment of cardiovascular risk factors: summary of published evidence Can Fam Physician 55, no. 7 (July 2009): 691–96.
- Tsonis, J. (2017). Sauna Studies as an Academic Field : A New Agenda for International Research, 41–82.
- Pilch W, Szygula Z, Palka T, et al. Comparison of physiological reactions and physiological strain in healthy men under heat stress in dry and steam heat saunas. Biol Sport. 2014;31(2):145–149. doi:10.5604/20831862.1099045
- C. Tei, T. Imamura, K. Kinugawa et al., “Waon therapy for managing chronic heart failure - Results from a multicenter prospective randomized WAON-CHF study,” Circulation Journal, vol. 80, no. 4, pp. 827–834, 2016.
- M. Miyata, T. Kihara, T. Kubozono et al., “Beneficial effects of waon therapy on patients with chronic heart failure: results of a prospective multicenter study,” Journal of Cardiology, vol. 52, no. 2, pp. 79–85, 2008.
- H. Miyamoto, H. Kai, H. Nakaura et al., “Safety and efficacy of repeated sauna bathing in patients with chronic systolic heart failure: a preliminary report,” Journal of Cardiac Failure, vol. 11, no. 6, pp. 432–436, 2005.
- S. Biro, A. Masuda, T. Kihara, and C. Tei, “Clinical implications of thermal therapy in lifestyle-related disease,” Experimental Biology and Medicine, vol. 228, no. 10, pp. 1245–1249, 2003.
- T. Kihara, S. Biro, M. Imamura et al., “Repeated sauna treatment improves vascular endothelial and cardiac function in patients with chronic heart failure,” Journal of the American College of Cardiology, vol. 39, no. 5, pp. 754–759, 2002.
- M. Sobajima, T. Nozawa, H. Ihori et al., “Repeated sauna therapy improves myocardial perfusion in patients with chronically occluded coronary artery-related ischemia,” International Journal of Cardiology, vol. 167, no. 1, pp. 237–243, 2013
- T. Ohori, T. Nozawa, H. Ihori et al., “Effect of repeated sauna treatment on exercise tolerance and endothelial function in patients with chronic heart failure,” American Journal of Cardiology, vol. 109, no. 1, pp. 100–104, 2012.
- Z.-D. Zhao, W. Z. Yang, C. Gao et al., “A hypothalamic circuit that controls body temperature,” Proceedings of the National Academy of Sciences, 2017.
- K. Kukkonen-Harjula, P. Oja, K. Laustiola et al., “Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath,” European Journal of Applied Physiology, vol. 58, no. 5, pp. 543–550, 1989.
- M. L. Hannuksela and S. Ellahham, “Benefits and risks of sauna bathing,” American Journal of Medicine, vol. 110, no. 2, pp. 118–126, 2001.
- Hussain, J., & Cohen, M. (2018). Clinical Effects of Regular Dry Sauna Bathing: A Systematic Review. Evidence-Based Complementary and Alternative Medicine, 2018, 1857413. https://doi.org/10.1155/2018/1857413
- ukkonen-Harjula, Katriina, Pekka Oja, Kai Laustiola, Ilkka Vuori, Jukka Jolkkonen, Simo Siitonen, and Heikki Vapaatalo. Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath European Journal of Applied Physiology and Occupational Physiology 58, no. 5 (March 1989): 543–50. doi:10.1007/bf02330710.
- Taggart, P., P. Parkinson, and M. Carruthers. Cardiac Responses to Thermal, Physical, and Emotional Stress BMJ 3, no. 5818 (July 1972): 71–76. doi:10.1136/bmj.3.5818.71
- Laukkanen, J. A., Laukkanen, T., & Kunutsor, S. K. (2018). Cardiovascular and Other Health Benefits of Sauna Bathing: A Review of the Evidence. Mayo Clinic Proceedings, 93(8), 1111–1121. https://doi.org/10.1016/j.mayocp.2018.04.008
- Laukkanen, T., Kunutsor, S. K., Zaccardi, F., Lee, E., Willeit, P., Khan, H., & Laukkanen, J. A. (2018). Acute effects of sauna bathing on cardiovascular function. Journal of Human Hypertension, 32(2), 129–138. https://doi.org/10.1038/s41371-017-0008-z
- Oosterveld, F.G.J., Rasker, J.J., Floors, M. et al. Infrared sauna in patients with rheumatoid arthritis and ankylosing spondylitis. Clin Rheumatol 28, 29 (2009). https://doi.org/10.1007/s10067-008-0977-y
- Mariotti A. The effects of chronic stress on health: new insights into the molecular mechanisms of brain-body communication. Future Sci OA. 2015;1(3):FSO23. Published 2015 Nov 1. doi:10.4155/fso.15.21
- Kojima, Daisuke, Takeshi Nakamura, Motohiko Banno, Yasunori Umemoto, Tokio Kinoshita, Yuko Ishida, and Fumihiro Tajima. Head-out immersion in hot water increases serum BDNF in healthy males International Journal of Hyperthermia 34, no. 6 (November 2017): 834–39. doi:10.1080/02656736.2017.1394502.
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