So you’ve heard about infrared saunas, and you’re wondering if a quick session before your workout is a performance hack. Maybe you’ve seen claims about improved circulation or faster recovery. Here’s the answer: maybe, but probably not in the way you’re hoping.
Limited research investigates how saunas affect exercise routine and ideal time to try them (David Church, PhD), and most studies look at sauna use in general—not right before or after exercise. The 2025 systematic review on the topic found only nine short-term recovery studies, and only two of those used infrared saunas specifically, which is why I was keen to explore infrared saunas with red light therapy after noticing big HRV increases from red light panels alone. David Church, PhD, Benjamin Gordon, PhD, Cas Fuchs, PhD, and Essi K. Ahokas have all pointed out that we’re working with indirect clues, not a settled protocol.
Fitness Drum’s trend data shows rising search interest in this topic, but the evidence base hasn’t kept up. This article is a guide to what we know—not a list of marketed benefits.
Key takeaways
- The 2025 systematic review found only 2 studies that examined infrared sauna for recovery, and results were split: 4 studies showed some benefit, 4 found no effect, and 1 showed worse performance
- Using a sauna before most workouts likely causes dehydration and increased body temperature, which hurts performance—except for athletes preparing to compete in hot weather
- Post-workout sauna has more supporting evidence but still has real limits: it may improve how you feel but doesn’t consistently speed up actual muscle repair
What Sauna Heat Does to Your Body (and Why Timing Matters)
Before you decide when to sauna, it helps to understand what’s happening under the skin.
Blood Flow, Heart Rate, and the Cardiovascular Upside
Heat makes your blood vessels dilate, which boosts circulation and sends more oxygen and nutrients through your body. Regular sauna use after exercise linked to lower cholesterol, blood pressure, better cardio fitness. That’s a real benefit, backed by studies like the 2015 JAMA Internal Medicine research that found regular sauna users had lower risks of heart disease and early death.
Heat exposure also raises your heart rate and makes you sweat—so much so that it can feel similar to light exercise. That’s why some people assume a sauna session counts as a workout. It doesn’t. Your heart might work harder, but you’re not building the same adaptations you get from actual movement.
The important caveat: these are long-term health associations, not proof of a pre-workout performance boost. Feeling like you “worked out” in the sauna is not the same as building training adaptations.
Sauna Stress Is Not Exercise Stress
Heat is a complement to your training, not a substitute.
The Evidence Gap: Only Two Infrared Sauna Recovery Studies
This is the check. The evidence for infrared sauna timing is thinner than most marketing suggests.
What the 2025 Review Actually Found
A 2025 systematic review examined whole-body heating after exercise—that includes infrared saunas, traditional saunas, and hot-water immersion. Here’s what it turned up:
- 14 studies with a total of 194 participants
- 9 studies examined short-term recovery, but only 2 used infrared saunas
- Results were split: 4 studies reported some benefit, 4 found no effect, and 1 observed worse performance
- Overall evidence quality was rated low to moderate, and every study had at least some risk of bias
The finding: whole-body heating showed little or no reliable effect on markers of muscle damage or inflammation. That’s a problem if you’re hoping the sauna will help your muscles repair faster.
Why the Infrared Recovery Picture Is So Hard to Trust
No placebo sauna exists. Participants always knew they were sitting in a hot room. That makes subjective reports of “feeling better” unreliable—you can’t separate the physiological effect from the expectation that heat should help.
As Benjamin Gordon, PhD, put it: “There’s not really much out there to really say clearly, ‘This is what actually happens in the body.'”
The difference participants feel might be warm muscles, not faster tissue repair. That’s not nothing, but it’s not the same as recovery.
Field note: The lack of a placebo control means “feeling better” after a sauna could be expectation, not physiology.
Pre-Workout Sauna: Why It Usually Backfires
If you’re thinking about hitting the sauna before training, here’s what you’re up against.
Pre-workout sauna dehydrates you and raises core temperature — both work against performance.
Dehydration and Heat Stress Can Sabotage Performance
For most sports, a sauna session before will likely cause dehydration (Fuchs) and increase your body temperature—neither of which helps you perform.
Pre-heating decreases exercise time to exhaustion in neutral environment and self-paced exercise intensity in hot environment (Essi K. Ahokas).
Dehydration could put you at risk for heat stroke or heat exhaustion, especially if exercising in heat after sauna (Gordon). As Gordon notes, if you’re already dehydrated from the sauna, exercising in heat could push you toward heat exhaustion or worse.
The Exception: Heat Acclimation for Hot-Weather Events
Only reason Fuchs could see a pre-exercise sauna session helping is for preparing for athletic event in hot weather. Spending time in a sauna over a few weeks before a hot-weather event can simulate those conditions and help your body adapt, and you can find discussions on infraredsaunas for more context on this approach.
This theory is supported mostly by a hot-water immersion study where 17 men exercised then bathed in 40°C water for 40 minutes on six consecutive days. That group experienced less physiological strain and improved 5km running performance in hot conditions. Those results can’t be applied to infrared heating, since the heat source and delivery are different.
For the average gym-goer training in a climate-controlled room, pre-workout sauna is unlikely to help and likely to hurt performance.
A Sauna Is Not a Warm-Up
Even though it increases body temperature and activates cardiovascular system, it doesn’t activate neuromuscular system (Ahokas).
The long-term effects of regular pre-workout sauna use on strength, muscle growth, or endurance are unknown. There is no dose-response data to guide optimal duration or temperature for a pre-workout sauna.
As Essi K. Ahokas from the University of Jyväskylä points out, no coach would recommend that route.
Older adults or anyone with joint pain or arthritis might theoretically feel less stiff during exercise after little time in sauna (Church). If you do decide to sauna bathe immediately before exercise, ‘keep it short and use milder temperatures’ (Ahokas).
Post-Workout Sauna: Recovery Benefits and Real Limits
If pre-workout sauna is mostly a risk, post-workout sauna has a stronger case—though it’s not the magic bullet some marketing suggests.
The relaxation you feel after a sauna can mask early fatigue signals, potentially leading you to push too hard in your next training session and increase injury risk.
What Post-Workout Sauna May Do Well
Post-workout sauna can improve how you feel. It may ease muscle soreness and promote relaxation, which can help you sleep better—and good sleep is essential for recovery indirectly. As Dr. Amy Zack notes, sore muscles often respond to heat, which is why a sauna can feel soothing after a tough workout. But using red light therapy after exercise can help speed recovery by increasing the quality and rate of tissue repair.
There’s also a physiological mechanism worth noting: regular post-workout sauna use can increase plasma volume, a condition called hypervolemia. Two trials showed athletes who took sauna baths after daily workouts showed increased plasma volumes, which enhances blood flow and delivers more oxygen and nutrients to muscles. That can increase stroke volume—the amount of blood your heart pumps per beat—which may improve performance.
The Physiological Catch: Skin Gets the Blood, Muscles Wait
Whole-body heating (versus localized heating) increases blood flow to skin in attempt to cool you down, rather than to muscles (Fuchs).
After intensive exercise, sauna bathing might be an extra stressor and slow down recovery (Ahokas). A small 2019 study published in the International Journal of Sports Physiology and Performance found that swimmers who sat in a sauna after their workout performed worse the next morning. If you worked out hard and lost a lot of fluids, you also risk worsening dehydration by sweating more in sauna afterward (Fuchs).
What Infrared Recovery Studies Actually Show
The two infrared-specific studies give a mixed picture. A a 2015 study reported that infrared sauna after an endurance workout improved jump recovery and eased muscle soreness—but it was only 10 men, so take that with a grain of salt. A 2023 study indicated partial benefit for jump performance and soreness in basketball players.
Neither study showed faster muscle repair or consistent recovery of strength or sprinting. Based on current research, sauna bathing is a possible tool to accelerate recovery and ease muscle soreness (Ahokas), but it’s not a substitute for proper nutrition, sleep, and active recovery.
Infrared vs. Traditional Sauna: What the Research Doesn’t Say
The “infrared” part of your question is important, because the answer is that we don’t have the data to say one is better for fitness.
How the Two Saunas Heat the Body Differently
Infrared saunas use radiant infrared energy to directly heat body; traditional saunas raise air temperature. This means infrared saunas operate at lower air temperatures—typically 40-60°C (100-140°F)—and warm up in about 15 minutes, which is one reason to consider a home infrared sauna. Traditional saunas run at 70-100°C and take 45-60 minutes to reach temperature.
The lower temperature makes infrared saunas more comfortable for longer sessions. That’s a difference in experience.
Why “Infrared Is Better” Isn’t Backed by Head-to-Head Data
No studies compare traditional and infrared saunas directly (Ahokas). The claimed benefits of specific infrared wavelengths—like deeper penetration into muscle tissue or cellular repair—are speculative, though infrared sauna market trends suggest growing commercial interest. Infrared cabins have a smaller footprint and lower electrical demand than traditional sauna enclosures, creating tradeoffs in contrast therapy equipment options for gyms.
Should You Ever Use an Infrared Sauna Before a Workout?
This depends on what kind of workout you’re doing and what your goals are.
Match Sauna Timing to Workout Type
For strength training, save the sauna for after. Pre-workout sauna can leave you dehydrated and drained, which undermines your ability to lift heavy or push hard.
For cardio and endurance training, same answer. Post-workout sauna is more supportive and restorative. Starting a run or bike ride in a heat-stressed state will make the session feel harder than it needs to be.
For yoga, flexibility work, mobility sessions, or recovery days, a short, mild pre-sauna session might actually help. The heat can loosen tight muscles and ease joint stiffness, making it easier to move through ranges of motion. This is the one scenario where pre-workout sauna makes sense.
For beginners, lean toward post-workout use and shorter durations (10-20 minutes). You don’t need to avoid saunas entirely, but starting after exercise is easier on your body while you learn how heat affects you.
The Separate-Time-of-Day Option
Experts like Cas Fuchs, PhD, suggest decoupling sauna from exercise entirely. If you sauna in the morning and train in the evening—or on separate days—you avoid the dehydration and performance declines that can happen in either direction.
The 20-Hours-Before Hypothesis
Researcher Essi K. Ahokas has a hypothesis: sauna about 20 hours before a workout might activate repair proteins that benefit muscle recovery. Might take that long to activate certain proteins that could help muscle repair, based on research on other whole-body heating methods.
No current research investigating this timing. Don’t rearrange your schedule around it until we have data.
Sauna Safety Rules You Can’t Ignore
Saunas are generally safe when used responsibly, but there are rules you need to follow.
Medical Clearance and Who Should Skip the Sauna
Get green light from doctor, especially if you have any kind of heart concerns. That said, a 2018 review in Mayo Clinic Proceedings noted that saunas can be safe for some people with heart disease—your doctor can help you find the right approach. Dr. Zack advises avoiding sauna use in certain situations and checking with a healthcare provider before use. Patients with asthma or COPD should also consult their primary care physician or specialist before sauna use.
Pregnant people should avoid saunas entirely, per the American College of Obstetricians and Gynecologists (ACOG).
Never use sauna if you’ve been drinking alcohol.
Hydration, Duration, and Session Limits
Typical safe sessions run 5 to 20 minutes. Infrared sauna with red light therapy works best when used 2-3 sessions per week, but start slower. Wear light, loose-fitting clothing such as shorts with no shirt, a sports bra, or swimsuit to stay comfortable and allow your skin to cool properly.
- Drink at least 8 ounces of water before your session
- Replenish fluids and electrolytes after
- Beginners: start with 15 minutes
- After a workout, wait 5-15 minutes before entering the sauna
- Allow 5-10 minutes of natural cool-down afterward before showering or hitting the cold plunge
Signs You Need to Stop
Dizziness, nausea, unusual weakness, headache, cramping, or confusion are red flags. Leave the sauna immediately and cool down. Listen to your body—heat stress can escalate quickly.
The Hype Gap: What Infrared Sauna Marketing Overpromises
Let’s be direct about what infrared sauna marketing gets wrong.
Claims Without Evidence: Detox, Deep Repair, Better Sleep
The idea that infrared saunas “detoxify” your body by sweating out toxins is not supported by research. Your liver and kidneys handle detoxification, not your sweat glands. These survey findings cannot prove that sauna use caused the reported benefits, so take anecdotal success stories with caution.
Deep muscle repair? The 2025 review found no consistent effect on muscle damage markers. Better sleep? A 2023 study reported no improvement in sleep duration or quality after infrared sauna use.
Weight loss? Sauna leads to water loss, not fat loss. You’ll weigh less on the scale immediately after, but that’s temporary dehydration, not body composition change.
What General Sauna Research Actually Supports
Better-supported claims include anxiety reduction, general sleep improvement (not specific to infrared), heart health benefits with regular use, and pain relief for conditions like arthritis and chronic back pain. These benefits come from regular sauna use over time, not from strategic timing around workouts.
The Placebo Problem in Sauna Studies
Many of the reported benefits could be placebo effects—especially since objective markers of muscle damage don’t consistently improve.
You can still use an infrared sauna and enjoy it. Just don’t expect it to be a magic repair tool for your muscles.
Bottom line: Sauna benefits are real for general wellness and relaxation, but the research doesn’t support using it as a pre-workout performance hack.
The Bottom Line: Use Saunas for Recovery, Not as a Pre-Game Ritual
Here’s the practical takeaway: for most people, the safest, most evidence-aligned approach is to save sauna bathing for after exercise or a separate part of the day.
Pre-workout sauna is mostly a performance risk unless you’re acclimating for a hot-weather event or doing very low-intensity mobility work. Post-workout sauna has more evidence behind it, but the benefits are modest and inconsistent—you might feel better, but your muscles aren’t necessarily repairing faster.
Use them as a tool for relaxation and general wellness, not as a pre-game ritual or a shortcut to fitness gains.
Frequently Asked Questions
Is 20 minutes in an infrared sauna enough?
For most people, 20 minutes is within the typical safe range of 5 to 20 minutes per session. Beginners should start with shorter sessions around 15 minutes to see how their body handles the heat. The key is to stay hydrated and listen to your body—if you feel dizzy or nauseous, it’s time to get out.
Can infrared saunas reduce belly fat?
No, infrared saunas do not reduce belly fat. Any weight lost immediately after a sauna session is water weight from sweating, not fat loss. Fat loss requires a calorie deficit from diet and exercise—sitting in a hot room won’t change your body composition.
What toxins do infrared saunas remove?
Infrared saunas do not remove toxins in any meaningful way. Your liver and kidneys are responsible for detoxification, not your sweat glands. While you do sweat out some water and electrolytes, the idea that saunas flush out heavy metals or other toxins is not supported by research.
What do 10 minutes in an infrared sauna do?
A 10-minute session can raise your heart rate, dilate blood vessels, and make you sweat, which may feel relaxing or mildly stimulating. However, it won’t produce significant fitness or recovery benefits on its own. For general wellness, shorter sessions are a safe starting point, but don’t expect performance gains.
Should I use an infrared sauna before or after a workout?
For most workouts, save the sauna for after exercise. Pre-workout sauna can cause dehydration and raise your body temperature, which hurts performance—especially for strength training or cardio. Post-workout sauna may help you feel better and ease soreness, but it doesn’t consistently speed up muscle repair.
Is there any research showing infrared saunas improve workout recovery?
The research is mixed and limited. A 2025 systematic review found only two studies that specifically looked at infrared saunas for recovery, with results split: some showed benefit, others found no effect, and one showed worse performance. Overall, the evidence quality is low to moderate, and no study has shown faster muscle repair.