The claim

“Sauna boosts testosterone.”

Stretched. In most sauna studies testosterone did not change, and the null results include a week of two hour-long sessions a day and three months of regular use. Two studies found short rises right after the heat, and one of those rises came only when men were pushed to exhaustion.

Updated Sep 24, 2026 · 1 study reviewed

A real finding has been pulled well past what the study showed.

People say it in places like these

Ben Greenfield's blog
Sauna usually raises your growth hormone and testosterone.
Men's health sites
A sauna session gives your testosterone a natural boost.

The research found this

Leppäluoto's 1986 study is best known for its 16-fold growth hormone figure. Its ten men sat at 80°C for an hour twice a day for seven days, and their testosterone did not change. Their LH and FSH levels held steady as well.Source 1 · Clinical trialEndocrine effects of repeated sauna bathingLeppäluoto J, Huttunen P, Hirvonen J, et al.. Acta Physiologica Scandinavica, 1986.Read the paper ↗PubMed ↗

Two studies found rises, and both measured them right after the heat. Eight young Finnish men took three sauna exposures, and testosterone rose only in the one that turned humid and ran until they were exhausted. By then their oral temperature had climbed 3.2°C.Source 2 · Clinical trialHaemodynamic and hormonal responses to heat exposure in a Finnish sauna bathKukkonen-Harjula K, Oja P, Laustiola K, et al.. European Journal of Applied Physiology and Occupational Physiology, 1989.Read the paper ↗PubMed ↗ The abstract does not say how big the rise was.

In the second study, 27 recreationally active men who were used to saunas sat in a traditional sauna at 70°C, and their testosterone was 15% higher at the post-sauna blood draw.Source 3 · Clinical trialAcute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a SaunaRissanen JA, Häkkinen A, Laukkanen J, et al.. Journal of Strength and Conditioning Research, 2020.Read the paper ↗PubMed ↗ Their maximal leg force was still 4.1% lower 24 hours later. When the men took the sauna after a workout, it added nothing to the hormone rise the exercise produced.

Other studies found no change. Thirty young men who did four 12-minute rounds at 90–91°C with cold plunges between them went from 4.04 to 4.24 ng/ml, and the change was not significant.Source 4 · Clinical trialEndocrine Effects of Repeated Hot Thermal Stress and Cold Water Immersion in Young Adult MenPodstawski R, Borysławski K, Pomianowski A, et al.. American Journal of Men's Health, 2021.Read the paper ↗PubMed ↗ Ten active men showed no change after 30 minutes in infrared and humid saunas at 35–50°C.Source 5 · Crossover trialEffects of far-infrared sauna bathing on recovery from strength and endurance training sessions in menMero A, Tornberg J, Mäntykoski M, et al.. SpringerPlus, 2015.Read the paper ↗PubMed ↗ Over three months of 15-minute sessions at 80–90°C twice a week, ten men had no significant change in sex hormones, while their sperm counts fell and later recovered.Source 6 · Clinical trialSeminal and molecular evidence that sauna exposure affects human spermatogenesisGarolla A, Torino M, Sartini B, et al.. Human Reproduction, 2013.Read the paper ↗PubMed ↗

Recent reviews land in the same place. A 2026 review of testosterone strategies in athletes called sauna neutral, and a 2025 review of men's health therapies found some temporary increases.Source 7 · ReviewTestosterone-Optimizing Strategies in AthletesLazarev A, Pujalte GG, Philibert C, et al.. Sports Health: A Multidisciplinary Approach, 2026.Read the paper ↗PubMed ↗Source 8 · Systematic reviewA systematic appraisal of emerging alternative therapies in men’s health and wellnessYazan Qaoud, Morcos M, Macdonald M, et al.. Canadian Urological Association Journal, 2025.Read the paper ↗PubMed ↗

The dial reads 68°H for four reasons

How the reading adds up

20 + 20 + 18 + 10 = 68°H

EvidenceWhat kind of evidence exists in people?
20/25
Several small studies have measured testosterone around sauna use, and most found no change, whether over one session or three months.Source 1 · Clinical trialEndocrine effects of repeated sauna bathingLeppäluoto J, Huttunen P, Hirvonen J, et al.. Acta Physiologica Scandinavica, 1986.Read the paper ↗PubMed ↗Source 4 · Clinical trialEndocrine Effects of Repeated Hot Thermal Stress and Cold Water Immersion in Young Adult MenPodstawski R, Borysławski K, Pomianowski A, et al.. American Journal of Men's Health, 2021.Read the paper ↗PubMed ↗Source 5 · Crossover trialEffects of far-infrared sauna bathing on recovery from strength and endurance training sessions in menMero A, Tornberg J, Mäntykoski M, et al.. SpringerPlus, 2015.Read the paper ↗PubMed ↗Source 6 · Clinical trialSeminal and molecular evidence that sauna exposure affects human spermatogenesisGarolla A, Torino M, Sartini B, et al.. Human Reproduction, 2013.Read the paper ↗PubMed ↗
ConsistencyHas the finding held up?
20/25
Two studies found rises right after the heat, and one of them saw the rise only at exhaustion in a humid sauna.Source 2 · Clinical trialHaemodynamic and hormonal responses to heat exposure in a Finnish sauna bathKukkonen-Harjula K, Oja P, Laustiola K, et al.. European Journal of Applied Physiology and Occupational Physiology, 1989.Read the paper ↗PubMed ↗Source 3 · Clinical trialAcute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a SaunaRissanen JA, Häkkinen A, Laukkanen J, et al.. Journal of Strength and Conditioning Research, 2020.Read the paper ↗PubMed ↗ The longer studies found none.Source 1 · Clinical trialEndocrine effects of repeated sauna bathingLeppäluoto J, Huttunen P, Hirvonen J, et al.. Acta Physiologica Scandinavica, 1986.Read the paper ↗PubMed ↗Source 6 · Clinical trialSeminal and molecular evidence that sauna exposure affects human spermatogenesisGarolla A, Torino M, Sartini B, et al.. Human Reproduction, 2013.Read the paper ↗PubMed ↗
MagnitudeDoes the claim match the size of the effect?
18/25
The largest rise on record was 15% at a blood draw right after the sauna.Source 3 · Clinical trialAcute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a SaunaRissanen JA, Häkkinen A, Laukkanen J, et al.. Journal of Strength and Conditioning Research, 2020.Read the paper ↗PubMed ↗ Neither study that saw a rise reports correcting for plasma volume lost in sweat.Source 2 · Clinical trialHaemodynamic and hormonal responses to heat exposure in a Finnish sauna bathKukkonen-Harjula K, Oja P, Laustiola K, et al.. European Journal of Applied Physiology and Occupational Physiology, 1989.Read the paper ↗PubMed ↗Source 3 · Clinical trialAcute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a SaunaRissanen JA, Häkkinen A, Laukkanen J, et al.. Journal of Strength and Conditioning Research, 2020.Read the paper ↗PubMed ↗
DoseDoes the studied protocol match how people use it?
10/25
The null results include realistic routines: 15 minutes at 80–90°C twice a week for three months, and four 12-minute rounds at 90–91°C.Source 6 · Clinical trialSeminal and molecular evidence that sauna exposure affects human spermatogenesisGarolla A, Torino M, Sartini B, et al.. Human Reproduction, 2013.Read the paper ↗PubMed ↗Source 4 · Clinical trialEndocrine Effects of Repeated Hot Thermal Stress and Cold Water Immersion in Young Adult MenPodstawski R, Borysławski K, Pomianowski A, et al.. American Journal of Men's Health, 2021.Read the paper ↗PubMed ↗ One of the two rises needed a humid sauna until the men felt exhausted.Source 2 · Clinical trialHaemodynamic and hormonal responses to heat exposure in a Finnish sauna bathKukkonen-Harjula K, Oja P, Laustiola K, et al.. European Journal of Applied Physiology and Occupational Physiology, 1989.Read the paper ↗PubMed ↗

The claim drifts from the data here

The claim turns two short-lived rises into a general boost. One needed a humid sauna run to exhaustion, and the other was a 15% bump measured straight after a session.Source 2 · Clinical trialHaemodynamic and hormonal responses to heat exposure in a Finnish sauna bathKukkonen-Harjula K, Oja P, Laustiola K, et al.. European Journal of Applied Physiology and Occupational Physiology, 1989.Read the paper ↗PubMed ↗Source 3 · Clinical trialAcute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a SaunaRissanen JA, Häkkinen A, Laukkanen J, et al.. Journal of Strength and Conditioning Research, 2020.Read the paper ↗PubMed ↗

Neither of those abstracts says the values were corrected for plasma volume. In one sauna study plasma volume fell 7% to 10.2%, and a smaller plasma volume raises the concentration of what remains in the blood.Source 9 · Clinical trialEffect of a Single Finnish Sauna Session on White Blood Cell Profile and Cortisol Levels in Athletes and Non-AthletesPilch W, Pokora I, Szyguła Z, et al.. Journal of Human Kinetics, 2013.Read the paper ↗PubMed ↗

The pituitary hormones with the most consistent responses to sauna are growth hormone and prolactin, and those changes return to normal within a couple of hours.Source 10 · ReviewEndocrine effects of sauna bathHuhtaniemi IT, Laukkanen JA. Current Opinion in Endocrine and Metabolic Research, 2020.Read the paper ↗Source 11 · ReviewHow the sauna affects the endocrine systemKukkonen-Harjula K, Kauppinen K. Annals of clinical research, 1988.Read the paper ↗PubMed ↗

Put it to use

Don't count on a sauna to raise your testosterone. If you train, the workout raised it in the one study that compared the two, and a sauna afterward added nothing.Source 3 · Clinical trialAcute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a SaunaRissanen JA, Häkkinen A, Laukkanen J, et al.. Journal of Strength and Conditioning Research, 2020.Read the paper ↗PubMed ↗

From our sister magazine

Sauna Monthly reviews saunas that hold the 80–90°C these studies used

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These outdoor saunas reach Finnish temperatures

Sauna Monthly compares barrels and cabins that run hot-rock heaters.

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The heater decides whether a room reaches 80°C

Sauna Monthly sizes electric heaters and wood stoves to the room.

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Check these claims next

60°H

Stretched

Heat

“A sauna session raises your growth hormone 16-fold.”

The 16-fold rise came from ten men doing two hour-long saunas a day for a week, and it faded by day three. One ordinary session gives a small, brief bump in younger men and none in older men.

30°H

Likely

Heat

“Regular sauna use lowers your sperm count.”

In a small Italian study, two 15-minute sessions a week at 80–90°C for three months cut sperm count and motility in 10 men. Every measured change had reversed six months after they stopped.

81°H

Hot air

Cold

“Cold plunges boost testosterone.”

The studies that measured it found testosterone falling or holding steady after cold water. A few minutes in water below 4°C lowered total testosterone by about 19% in young men, and a 15°C soak after squats blunted the usual post-workout rise.

We cited these sources

01Leppäluoto J, Huttunen P, Hirvonen J, Väänänen A, Tuominen M, Vuori J. Endocrine effects of repeated sauna bathing. Acta Physiologica Scandinavica. 1986;128(3):467-470. doi:10.1111/j.1748-1716.1986.tb08000.x PMID 3788622
02Kukkonen-Harjula K, Oja P, Laustiola K, Vuori I, Jolkkonen J, Siitonen S, et al.. Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath. European Journal of Applied Physiology and Occupational Physiology. 1989;58(5):543-550. doi:10.1007/BF02330710 PMID 2759081
03Rissanen JA, Häkkinen A, Laukkanen J, Kraemer WJ, Häkkinen K. Acute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a Sauna. Journal of Strength and Conditioning Research. 2020;34(2):313-322. doi:10.1519/JSC.0000000000003371 PMID 31490429
04Podstawski R, Borysławski K, Pomianowski A, Krystkiewicz W, Żurek P. Endocrine Effects of Repeated Hot Thermal Stress and Cold Water Immersion in Young Adult Men. American Journal of Men's Health. 2021;15(2):15579883211008339. doi:10.1177/15579883211008339 PMID 33845653
05Mero A, Tornberg J, Mäntykoski M, Puurtinen R. Effects of far-infrared sauna bathing on recovery from strength and endurance training sessions in men. SpringerPlus. 2015;4:321. doi:10.1186/s40064-015-1093-5 PMID 26180741
06Garolla A, Torino M, Sartini B, Cosci I, Patassini C, Carraro U, et al.. Seminal and molecular evidence that sauna exposure affects human spermatogenesis. Human Reproduction. 2013;28(4):877-885. doi:10.1093/humrep/det020 PMID 23411620
07Lazarev A, Pujalte GG, Philibert C, Meek SE, Broderick GA, Zapp DG, et al.. Testosterone-Optimizing Strategies in Athletes. Sports Health: A Multidisciplinary Approach. 2026;18(3):477-488. doi:10.1177/19417381251411933 PMID 41630126
08Yazan Qaoud, Morcos M, Macdonald M, Shoeib A, Qureshi Y, Mak M, et al.. A systematic appraisal of emerging alternative therapies in men’s health and wellness. Canadian Urological Association Journal. 2025;20(4). doi:10.5489/cuaj.9368 PMID 41406341
09Pilch W, Pokora I, Szyguła Z, Pałka T, Pilch P, Cisoń T, et al.. Effect of a Single Finnish Sauna Session on White Blood Cell Profile and Cortisol Levels in Athletes and Non-Athletes. Journal of Human Kinetics. 2013;39:127-135. doi:10.2478/hukin-2013-0075 PMID 24511348
10Huhtaniemi IT, Laukkanen JA. Endocrine effects of sauna bath. Current Opinion in Endocrine and Metabolic Research. 2020;11:15-20. doi:10.1016/j.coemr.2019.12.004
11Kukkonen-Harjula K, Kauppinen K. How the sauna affects the endocrine system. Annals of clinical research. 1988;20(4):262-266. PMID 3218898

People say it in places like these

The research found this

The dial reads 68°H for four reasons

EvidenceWhat kind of evidence exists in people?

ConsistencyHas the finding held up?

MagnitudeDoes the claim match the size of the effect?

DoseDoes the studied protocol match how people use it?