How sauna affects recovery and performance for running, OCR, and endurance sports
Thomas Solomon, PhD.
Updated onReading time approx 7 minutes (1500 words).
What you’ll learn:
A sauna is a hot room (often wooden) where people sit to relax, sweat, and feel very Scandinavian for a bit.
Right now, it’s unclear whether sauna boosts post-exercise recovery. But regular post-exercise sauna can help you adapt to heat (heat acclimation), which may improve endurance performance in hot conditions.
Curious about the how and why? Scroll down for the details, the nuances, and the nerdy bits.
The information I provide is not medical advice. Before making any changes to your habits of daily living based on any information I provide, always ensure it is safe for you to do so and consult your doctor if you are unsure.
What is sauna?
A sauna is usually a small heated room—often a wooden cabin—with heat coming from hot stones/embers. The air temperature is typically around 60 to 80°C (140 to 176°F). Some saunas are “wet” (you throw water on the hot stones, humidity goes up—often more than 50%). Others are “dry” (low humidity—often less than 20%). Either way, the core experience is basically: you sit, you heat up, you sweat, you think about life choices.
In a wet sauna, you usually feel sweaty because the air is already humid, so sweat doesn’t evaporate as easily. In a dry sauna, you can still sweat a lot, but the sweat can evaporate fast—so you might feel oddly less drenched, even though you’re still losing fluid. Many people walk out feeling relaxed, refreshed, and ready to hug a tree. Many also do not. I sit in the latter camp. A sauna makes me feel extra fatigue-y, like my body is filing a formal complaint. The one part I genuinely like is breathing in the warm air, which my asthma-infested lungs find weirdly soothing. Ah, the complexity of life.
The list of proposed health benefits of sauna is, errr, longer than a blue whale’s migration route. Some podcasters and “influencers” regularly promote sauna as a miracle tool (e.g. here). And to be fair, some experimental studies report that regular sauna use can reduce stress, anxiety, inflammation, etc (reviewed here and here).
One of the biggest datasets comes from Finland: the Kuopio Ischemic Heart Disease Risk Factor Study. It followed about 3000 middle-aged Finnish men and women for 20 years and found that sauna use was associated with lower risk of hypertension (high blood pressure), stroke, cardiovascular-related mortality (death), and dementia (including Alzheimer’s disease), even after accounting for age, socioeconomic status, diet, and physical activity.
That sounds impressive — and it is interesting — but it’s important to remember what this type of evidence can (and can’t) prove. These findings mostly come from a cohort studyA cohort study is a type of observational study that follows a group (a cohort) over time to see how exposures affect outcomes. I.e., a cohort study tracks people forward (prospective) to see what happens. Cohort studies are used to study causes and risk factors over time, and can show the association between exposure and outcome or new cases over time (incidence). E.g., Does regular running reduce the risk of heart disease over 10 years? design where people report habits (like sauna use) rather than being assigned to a sauna routine. To show a direct cause-and-effect relationship, we’d need a randomised controlled trialThe “gold standard” approach for determining whether a treatment has a causal effect on an outcome of interest. In such a study, a sample of people representing the population of interest is randomised to receive the treatment or a no-treatment placebo (control), and the outcome of interest is measured before and after exposure to the treatment and control..
Some evidence — mostly from animal models — also suggests passive heat exposure (like sauna) without exercise might help maintain muscle mass and/or force development (see here and here). But, again, we need more high-quality human trials before we can say that with confidence.
Also yes, the Finns absolutely swear by sauna. I’ve been lucky enough to sauna with many a Finn across their great country — many apartment buildings literally have a sauna in the basement. And nothing beats giving a scientific talk to university academics when several of them have already seen your full monty in the sauna earlier that day. Academia is glamorous.
Anyway. Let’s bring this back to runners, OCR athletes, and endurance training: what about sauna for recovery of performance after exercise?
What is the scientific evidence on the effect of sauna on recovery and athletic performance?
Quick note: this section is about recovering performance after training (and adapting to training). It is not about recovering from injury/illness, and it’s not a deep dive into sauna for general health maintenance.
Also: this is not a heat-acclimation “how-to” guide. If you want that rabbit hole (it’s a good one), go here: veohtu.com/heatacclimation.
When you sit in a sauna, lots of “exercise-like” things happen: heart rate goes up, breathing rate goes up, sweat rate goes up, oxygen consumption (VO2) increases, cardiac output increases, and blood pressure changes. But here’s the key point: short-term changes during heat exposure are not automatic proof of long-term benefits. Often, they just show your body trying to keep itself stable (maintain homeostasis) under heat stress. A bacterial or viral infection can also raise heart rate and oxygen consumption — so “it looks like exercise” is not the same as “it causes the same adaptations.” Be wary of anyone selling that leap as settled science (e.g. here and here).
Because heat exposure increases sweating, pay attention to thirst and drink enough to stay hydrated. Dehydration can impair recovery from training and blunt how well you adapt to training. Also, always avoid heat stress — so if you feel like poop, exit the (hot) building. (Hydration deep dive here: veohtu.com/hydration-1-whatweknow.)
Most sauna research that’s relevant to exercise recovery has been done in rodents. That’s useful for ideas and mechanisms, but it does not automatically translate to humans (sadly, we are not just giant hairless mice with Garmin watches).
There are very few human studies on sauna and post-exercise recovery, and there is currently no meta-analysisA meta-analysis quantifies the overall effect size of a treatment by compiling effect sizes from all known studies of that treatment. that focuses on this topic.
The small human literature is mixed. Some studies found that post-exercise sauna can impair next-day performance, including a study reporting worse swimming time trial performance the following day (30 trained swimmers and triathletes). Another study reported that maximal voluntary contraction (MVC) force, a marker of muscle strength, is reduced following a sauna in untrained people. So, it’s probably unwise to sauna immediately before, or even the day before, a maximal-effort session or race. On the flip side, one small study in 10 healthy men found that a far-infrared sauna after a ~40-min maximal-effort endurance session may restore neuromuscular performance (countermovement jump height). Bottom line: we need larger, better-controlled trials to know what’s real and what’s noise.
Practical take: if you consistently leave the sauna feeling calm, loose, and psychologically “reset,” then it might be useful for you. If you leave feeling flattened, cooked, or grumpy, then congratulations: you’ve just learned something about your own physiology, and you don’t need to force sauna into your recovery toolbox. That said, using post-exercise sauna as part of a heat acclimation strategy might improve performance in the heat (see veohtu.com/heatacclimation).
Can sauna enhance recovery and athletic performance?
Because there are so few good human studies, it’s currently unclear how post-exercise sauna affects recovery of performance after training.
That said, regular post-exercise heat exposure (hot water immersion or sauna) is likely to induce heat acclimation, which may improve endurance performance in the heat (go deep on heat acclimation at veohtu.com/heatacclimation). However, the current evidence suggests that the effect sizeA meta-analysis quantifies the overall effect size of a treatment by compiling effect sizes from all known studies of that treatment. is trivial to small.
Because of limited research, it’s unclear whether effects differ between trained athletes and untrained people, and between males and females.
Across the limited studies available, effects look broadly similar in trained and untrained participants, and in males and females. But, because the evidence is sparse, these comparisons are uncertain. Also, more research is needed in females because women are underrepresented in this field.
Keep in mind: because of limited research, the overall certainty of evidenceCertainty of evidence tells us how confident we are that the published results accurately reflect the true effect. It’s based on factors like study design, risk of bias, consistency, directness, precision, and publication bias. Low certainty means more doubt and less confidence, and that future studies could easily change the conclusions. High certainty means that the current evidence is so strong and consistent that future studies are unlikely to change conclusions. is lowA low quality of evidence means that, in general, studies in this field have several limitations. This could be due to inconsistency in effects between studies, a large range of effect sizes between studies, and/or a high risk of bias (caused by inappropriate controls, a small number of studies, small numbers of participants, poor/absent randomization processes, missing data, inappropriate methods/statistics). When the quality of evidence is low, there is more doubt and less confidence in the overall effect of an intervention, and future studies could easily change overall conclusions. The best way to improve the quality of evidence is for scientists to conduct large, well-controlled, high-quality randomized controlled trials.. Additional high-quality randomised controlled trials are needed to understand potential effects and (eventually) to enable a proper meta-analysis.
The nice part: for most people, post-exercise sauna doesn’t look like a consistent recovery “harm”. That said, a few studies suggest it can impair next-day performance, especially if you do it close to a maximal effort. So, if you like sauna and it makes you feel good, fine — use it. Just remember that time and money spent doing a recovery method with no clear benefit might be better spent sitting down, resting, eating something nutritious, and doing something calm. Also be aware that because increased core temperature can impair performance, pre-exercise heat exposure is probably best to avoid. Read all about that at veohtu.com/heat.
Also remember that drinking to thirst to prevent sauna-induced dehydration will help prevent dehydration-related drops in recovery and performance. And always leave the sauna if you feel unwell. Go deep on hydration at veohtu.com/hydration.
How to use this: If you’re going to sauna, treat it like a comfort tool, not a magic spell. Keep it away from key maximal-effort workouts and race days (and ideally the day before). Use it after easier sessions if it helps you unwind, and drink enough to satisfy thirst. If you leave feeling wrecked, skip it — your recovery “plan” is allowed to be boring.
Information you can trust. All content on Veohtu is meticulously researched and written by Thomas Solomon, PhD. He does not sell supplements, recovery products, or ad space, and he has no sponsorships, brand affiliations, or ambassador roles. Everything you read reflects his independent views, shaped solely by peer-reviewed scientific evidence — and that will never change.
Full list of meta-analyses examining sauna for recovery
Here are the meta-analyses I've summarised above:
There are currently no meta-analyses of sauna for recovery from exercise. However, there are some analyses examining the role of post-exercise heat exposure (via a hot bath or sauna) on heat acclimation and performance:
Effects of Post-Exercise Heat Exposure on Acute Recovery and Training-Induced Performance Adaptations: A Systematic Review. Ahokas et al. Sports Med Open. 2025
The effect of post-exercise heat exposure (passive heat acclimation) on endurance exercise performance: a systematic review and meta-analysis. Solomon and Laye. BMC Sports Sci Med Rehabil. 2025
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Who is Thomas Solomon?
My knowledge has been honed following 20+ years of running, cycling, hiking, cross-country skiing, lifting, and climbing, 15+ years of academic research at world-leading universities and hospitals, and 10+ years advising and coaching in athletic performance and lifestyle change.
I have a BSc in Biochemistry, a PhD in Exercise Science, and over 90 peer-reviewed publications in medical journals.
I'm also an ACSM-certified Exercise Physiologist (ACSM-EP), an ACSM-certified Personal Trainer (ACSM-CPT), a VDOT-certified Distance Running Coach, and a UKVRN Registered Nutritionist (RNutr).
Since 2002, I’ve conducted biomedical research in exercise and nutrition and have taught and led university courses in exercise physiology, active recovery, biochemistry, and molecular medicine.
And, with my personal experience of competing on the track (800m to 10,000m), the road (5 k to marathon), on the trails, and in the mountains, by foot, bicycle, cross-country ski, and during obstacle course races (OCR), I deeply understand what it's like to train and compete — I've been there, done it, and gotten sweat, mud, and tears on my t-shirt.
Disclaimer: I occasionally mention brands and products, but it is important to know that I don't sell recovery products, supplements, or ad space, and I'm not affiliated with / sponsored by / an ambassador for / receiving advertisement royalties from any brands. I have conducted biomedical research for which I’ve received research money from publicly-funded national research councils and medical charities, and also from private companies, including Novo Nordisk Foundation, AstraZeneca, Amylin, the A.P. Møller Foundation, and the Augustinus Foundation. I’ve also consulted for Boost Treadmills and Gu Energy on R&D grant applications, and I provide research and scientific writing services for Examine.com. Some of my articles contain links to information provided by Examine.com but I do not receive any royalties or bonuses from those links. Importantly, none of the companies described above have had any control over the research design, data analysis, or publication outcomes of my work. I research and write my content using state-of-the-art, consensus, peer reviewed, and published scientific evidence combined with my empirical evidence observed in practice and feedback from athletes. My advice is, and always will be, based on my own views and opinions shaped by the scientific evidence available. The information I provide is not medical advice. Before making any changes to your habits of daily living based on any information I provide, always ensure it is safe for you to do so and consult your doctor if you are unsure.