The claim

“Sauna boosts testosterone.”

Stretched. Most sauna studies, including a week of two hour-long sessions a day and three months of regular use, found no change in testosterone. Two studies found short rises right after the heat, and one of those came only when men stayed in until they were exhausted.

Updated Sep 24, 2026 · 1 study reviewed

The claim pulls a real finding 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 in an 80°C sauna for an hour twice a day for seven days. Their testosterone didn't change, and the pituitary hormones LH and FSH held steady too.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. In the first, eight young Finnish men took three sauna exposures, and their 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 doesn't give the size of the rise.

In the second study, 27 recreationally active men who were used to saunas sat in a traditional sauna at 70°C, and blood drawn right afterward showed their testosterone 15% higher.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 from the exercise.

The other studies found no change. Thirty young men did four 12-minute rounds at 90–91°C with cold plunges in between. Their testosterone went from 4.04 to 4.24 ng/ml, and the change wasn't statistically 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 ↗ In ten active men, 30 minutes in infrared and humid saunas at 35–50°C left testosterone flat.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. 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 see it much the same way. 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 human evidence exists?
20/25
Several small studies have measured testosterone around sauna use. Most of them found no change, and they ran from one session to 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 ↗
ConsistencyHave other studies found the same thing?
20/25
The two rises on record both came in blood drawn straight after the heat, and one appeared only when a humid sauna ran until the men were 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 ↗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 week-long and three-month studies found no rise.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 the fluid the blood loses to 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 dose match how people use it?
10/25
Routines that look like real use, such as 15 minutes at 80–90°C twice a week for three months or four 12-minute rounds at 90–91°C, found no change.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 that ran 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 the fluid lost in sweat. In one sauna study, plasma volume fell 7% to 10.2%, and less fluid in the blood makes everything in it more concentrated.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 that respond to sauna most consistently are growth hormone and prolactin, and both 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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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 after the third day. 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, 10 men took two 15-minute sessions a week at 80–90°C for three months, and their sperm count and motility (how well sperm swim) dropped. Every change the researchers measured had reversed six months after the men stopped.

81°H

Hot air

Cold

“Cold plunges boost testosterone.”

The studies that measured testosterone found it 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 human evidence exists?

ConsistencyHave other studies found the same thing?

MagnitudeDoes the claim match the size of the effect?

DoseDoes the studied dose match how people use it?