With heart disease reaching crisis levels yet most unable to exercise adequately, could simply sitting and sweating in an infrared sauna truly provide comparable cardiovascular benefits?

Regular infrared sauna use provides significant cardiovascular benefits akin to exercise - including enhanced vascular function, lowered blood pressure, reduced inflammation and oxidative stress. Likely mechanisms relate to increased nitric oxide, heat shock proteins, and improved autonomic balance. As cardiovascular disease escalates yet recommendations falter, accessible passive heating via infrared saunas offers therapeutic potential for supporting heart health.

While exercise remains paramount for health, research suggests infrared saunas also provide impressive benefits like heart-protective effects and anti-aging influences. Emerging data reveals American adults increasingly use these whole-body heat therapies aiming to relieve stress or treat medical conditions.¹ In fact, a rapidly growing portion of our Greenmedinfo.com readership is interested in infrared therapy, with our most popular infrared sauna products enjoyed by them found here on our Regenerate Project store. However, despite growing interest among the public, much uncertainty still lingers around how passive sweating and the elevation of bodily temperature physically impacts the body despite infrared saunas growing accessibility.² So in a unique randomized crossover trial, Australian scientists compared physiological responses in premenopausal women using infrared heating versus moderate-intensity exercise.³

In the new clinical study, 10 participants underwent 45 minutes of infrared sauna at 60°C (140° F), exercise bicycling optimizing 55-70% maximal heart rate, or resting as control. Sauna pushed core body temperatures over 1°C higher; more than exercising or resting per tympanic measurements. It also elevated back skin temperature before activating the cooling effects of sweating. Breathing rates increased far more during exercise versus negligible change in infrared. Otherwise, blood pressure, heart rate variability and arterial elasticity showed no significant differences between sauna, exercising or control states in these healthy women.³

This evidence suggests infrared heating largely triggers thermoregulatory rather than cardiovascular adaptations like exercise. The authors proposed higher exertion or sicker cohorts could reveal more crossovers between sauna and training. Still, they reaffirmed infrared provides genuine physiological heat stress distinct from just passive resting.³ 

This may help explain the remarkable results of Finnish research which found frequent sauna bathing contributes to 40% lower all-cause mortality nearly comparable to exercising.⁴ Additional plausible mechanisms span lowering blood pressure, dampening inflammation and oxidative damage, improving microcirculation and vascular function, positively modulating the nervous system and more.^5-11 Even more amazing perhaps, is that real-world data shows over 60% reduced cardiovascular deaths, 14% less heart failure and 41% fewer heart attacks in consistent sauna users.^12,13 Given more people struggle to exercise adequately versus conveniently accessing passive heating, understanding the physical sauna-training parallels seems imperative for lifestyle medicine. In fact, if sauna bathing were an FDA approved drug it would be considered unethical NOT to use it as a standard of care, given how profoundly positive are its potential health impacts. 

Enhanced Vascular Function - Minus The Sweat 

Regular aerobic training demonstrably boosts blood vessel elasticity and endothelial function decentralizing vascular resistance. This effect helps lower elevated blood pressure.14 Similarly, clinical trials using various heating modalities report enhanced flow-mediated dilation indicating augmented arterial compliance.15-18 Thirty minutes of infrared at 60°C also improves vasodilation in heart failure patients unable to exercise.16 So saunas can emulate exercise’s vascular conditioning without all the exertion.

Infrared heating and exercise both stimulate nitric oxide release - an endothelial mediator that relaxes smooth muscle, regulates clotting and provides localized antioxidant effects.17 This vasoactive compound appears vital to the positive vascular changes observed with saunas and workouts.¹⁹ Likely this nitric oxide boost underpins sauna-linked lowered blood pressure and reduced arterial stiffness noted occasionally after brief sessions yet more pronounced over three months of regular use.^20-23

Limiting inflammation and oxidation

Inflammation not only underlies atherosclerosis progression but also links obesity to insulin resistance and cardiovascular complications. Meanwhile oxidative stress occurs naturally yet modern high-calorie diets and sedentary behaviors exacerbate free radical formation contributing to endothelial dysfunction plus nervous and immune issues amongst others.^24,25 Positive exercise-induced myokines like interleukin-6 exert direct anti-inflammatory effects while boosting antioxidant capacity provides indirect relief.^26,27 Though do saunas deliver similar anti-inflammatory and antioxidant advantages?

Emerging research suggests yes - sauna bathing acutely limits inflammatory markers like interleukins and TNF-alpha while concomitantly enhancing glutathione and superoxide dismutase antioxidants.²⁸ Long-term sessions expand heat shock proteins that stabilize cell structure against stress. Elderly regular sauna users even show biomarkers of somehow reversed vascular aging.²⁹ However intricacies behind the heat-hormesis response remain debated given such clear free radical elevation during heating only to rebound afterwards. Likely multilayered processes spanning improved circulation, tissue perfusion and nervous system balance interplay with hormetic gene activation to jointly limit oxidative stress over months and years of consistent thermal therapy.^30-35

Cardiovascular benefits over time

Recently experts in cardiovascular medicine concluded sauna bathing "has emerged as a lifestyle practice with a positive impact on overall health and CVD prevention" urging it be integrated into clinical strategies for modifiable CVD risk factors.³⁶ Mechanisms proposed include lowering peripheral resistance and central blood pressure, stimulating atrial natriuretic peptides while inhibiting vasoconstrictors, directly boosting endothelial nitric oxide synthase expression, improving autonomic balance and platelets function and upregulating cardioprotective gene transcription factors.³⁷

This accords with data revealing four-plus weekly sauna halves cardiovascular and all-cause mortality versus rare use.³⁸ Beyond dramatic risk slashing for sudden cardiac deaths and fatal heart attacks, additional long-term tracking connects regular passive heating to 51% reduced stroke incidence and 61% lowered dementia.^37,39 Still whether infrared specifically offers proportional protections as traditional dry saunas awaits confirmation - though early signs look promising.⁴⁰ Regardless more cardiovascular clinicians now rightfully recognize and even prescribe sauna therapies alongside exercise aiming to prevent and treat heart issues using lifestyle approaches.³⁶

Take-home message

Exercise never becomes fully replaceable given training-specific structural adaptations and metabolic signaling pathways exceeding passive heating’s effects. Nonetheless, extensive research now demonstrates sauna provides genuine vascular and metabolic benefits worth integrating alongside physical activity into weekly health routines. With cardiovascular disease and metabolic dysfunction reaching crisis levels yet most practice recommendations ignored, accessible passive heating offers safe therapeutic potential for supporting heart health and function in those willing to simply sit back and sweat. ³⁷

Learn more about the health benefits of sauna bathing by consulting our database on the subject here: www.greenmedinfo.com/therapeutic-action/sauna-therapy

References 

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2. Hooper PL. Hot-tub therapy for type 2 diabetes mellitus. N Engl J Med. 1999;341(12):924-925.

3. Hussain JN, Cohen MM, O'Malley CJ, Mantri N, Greaves RF. Infrared sauna as exercise-mimetic? Physiological responses to infrared sauna vs exercise in healthy women: A randomized controlled crossover trial. Complement Ther Med. 2022;102798.

4. Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med. 2015;175(4):542-548.

5. Lee E, Laukkanen T, Kunutsor SK, et al. Sauna exposure leads to improved arterial compliance: Findings from a non-randomised experimental study. Eur J Prev Cardiol. 2018;25(2):130-138.

6. Kunutsor SK, Laukkanen T, Laukkanen JA. Longitudinal associations of sauna bathing with inflammation and oxidative stress: the KIHD prospective cohort study. Ann Med. 2018;50(5):437-442.

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9. Masuda A, Nakazato M, Kihara T, Minagoe S, Tei C. Repeated thermal therapy diminishes appetite loss and subjective complaints in mildly depressed patients. Psychosom Med. 2005;67:643-647.

10. Sutkowy P, Woźniak A, Boraczyński T, Mila-Kierzenkowska C, Boraczyński M. The effect of a single Finnish sauna bath after aerobic exercise on the oxidative status in healthy men. Scand J Clin Lab Invest. 2014;74(2):89-94.

11. Pilch W, Pokora I, Szyguła Z, Pałka T, Pilch P, Cisoń T, Malik L, Wiecha S. Effect of a single finnish sauna session on white blood cell profile and cortisol levels in athletes and non-athletes. J Hum Kinet. 2013;39:127-135.

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20. Gayda M, Paillard F, Sosner P, et al. Effects of sauna alone and postexercise sauna baths on blood pressure and hemodynamic variables in patients with untreated hypertension. J Clin Hypertens (Greenwich). 2012;14(8):530-534.

21. Radtke T, Poerschke D, Wilhelm M, et al. Acute effects of Finnish sauna and cold-water immersion on haemodynamic variables and autonomic nervous system activity in patients with heart failure. Eur J Prev Cardiol. 2016;23(6):593-601.

22. Lee E, Laukkanen T, Kunutsor SK, et al. Sauna exposure leads to improved arterial compliance-Findings from a non-randomized experimental study. Eur J Prev Cardiol. 2018;25(2):130-138.

23. Laukkanen T, Kunutsor SK, Khan H, Wakayo T, Kauhanen J. Long-term sauna bathing habit and risk of hypertension in middle-aged Caucasian men: A long-term prospective cohort study. Mayo Clin Proc. 2022;97(6):1057-1066.

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28. Sutkowy P, Woźniak A, Boraczyński T, Mila-Kierzenkowska C, Boraczyński M. The effect of a single Finnish sauna bath after aerobic exercise on the oxidative status in healthy men. Scand J Clin Lab Invest. 2014;74(2):89-94. 

29. Laukkanen T, Kunutsor SK, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle-aged Finnish men. Age Ageing. 2017;46(2):245-249.

30. Masuda A, Kihara T, Fukudome T, Shinsato T, Minagoe S, Tei C. The effects of repeated thermal therapy for two patients with chronic fatigue syndrome. J Psychosom Res. 2005;58(4):383-387.

31. Crinnion WJ. Sauna as a valuable clinical tool for cardiovascular, autoimmune, toxicant-induced and other chronic health problems. Altern Med Rev. 2011;16(3). 215-225.

32. Sutkowy P, Woźniak A, Boraczyński T, Mila-Kierzenkowska C, Boraczyński M. The effect of a single Finnish sauna bath after aerobic exercise on the oxidative status in healthy men. Scand J Clin Lab Invest. 2014;74(2):89-94.

33. Pilch W, Pokora I, Szyguła Z, Pałka T, Pilch P, Cisoń T, Malik L, Wiecha S. Effect of a single finnish sauna session on white blood cell profile and cortisol levels in athletes and non-athletes. J Hum Kinet. 2013 Dec 27;39:127-35.

34. Kauppinen K. Sauna, shower, and ice water immersion. Physiological responses to brief exposures to heat, cool, and cold. Part II. Circulation. Arctic Med Res. 1989;48(2):64-74.

35. Coimbra S, Castro E, Rocha-Pereira P, Rebelo I, Rocha S, Pu S. The effect of repeated thermal therapy on quality of life in patients with type II diabetes mellitus. J Altern Complement Med. 2012;18(8):776-779.

36. Bullón S, Roman-Viñas B, Alcázar J, et al. Effect of thermal therapy using hot water bottles on blood pressure and quality of life in normotensive and mild or controlled hypertensive adults: A randomized pilot clinical trial. Complement Ther Med. 2020;53:102526. Published 2020 Oct 16.

37. Kunutsor SK, Laukkanen T, Laukkanen JA. Sauna bathing reduces the risk of cardiovascular disease mortality in Finnish men and women-A prospective cohort study. Exp Ther Med. 2022.

38. Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med. 2015;175(4):542-548.

39. Laukkanen T, Kunutsor S, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer’s disease in middle-aged Finnish men. Age Ageing. 2017;46:245-249. 

40. Beever R. Far-infrared saunas for treatment of cardiovascular risk factors: summary of published evidence. Can Fam Physician. 2009;55(7):691-696.