What Should You Do Before, During, and After a Sauna Session?

Written by: Kate Korom
Published on: November 2, 2026

You warm up before a workout and cool down after it. A sauna session works the same way.²

Heat is a mild, controlled stressor. Your heart rate rises, your blood vessels widen, and you sweat to shed heat. In a Finnish study of 100 adults, one 30-minute sauna session lowered average systolic blood pressure from 137 to 130 mmHg.³ The same group showed improved arterial compliance right after the session.⁴

Those shifts are part of why sauna use is so well tolerated. A 2018 systematic review of 40 clinical studies and 3,855 participants found only one small study reporting an adverse effect.⁵ Still, a short warmup and cooldown routine before and after each session helps your body adjust smoothly.

An infrared sauna adds a twist. It warms your body directly, so the air feels gentler than a traditional sauna. You can sweat freely without feeling overheated, which makes hydration easy to underestimate.

Drink at least 8 oz of water

Sunlighten recommends at least 8 oz of water before you step in, to prepare for the rise in core temperature.¹ The American College of Sports Medicine advises starting to hydrate “several hours before” heat stress, not just minutes before.⁶ A glass with your “before” routine, plus one right before your session, covers both.

Preheat your sauna

Preheat your Sunlighten sauna for 45–60 minutes. It warms about one degree per minute, depending on room temperature.² Signature and Amplify saunas can start automatically in Reservation Mode. On the mPulse Intelligent Sauna, you can schedule a start time or use the preheat setting built into any program.²

Set out your towels

Lay one towel on the bench to absorb sweat and keep a second nearby for your face.² Sunlighten’s CELLIANT® towels are designed for this.

Check your health first

If you are pregnant, take medication, or have a heart or other medical condition, talk with your doctor first. Review Sunlighten’s contraindications page before your first session.⁷

Pick a program for your goal

Decide what you want from the session: unwinding, recovering, or simply relaxing before bed. The mPulse Intelligent Sauna offers goal-based programs for Relaxation and Muscle Recovery, powered by the PulseIQ™ infrared intelligence platform. Choosing one upfront takes the guesswork out of time and temperature.

Start slow and build up

If you are new to infrared, Sunlighten recommends 10–15 minute sessions at 100°F, every other day.¹ Keep early sessions at or below 130°F.¹ Over time, build toward 40-minute daily sessions in your ideal temperature range.² For a full progression, see How Long Should You Stay in a Sauna?

Take a cooling break if you need one

You don’t have to finish a session in one stretch. If you feel too warm, open the door or step out for a few minutes. Sip some water, let your breathing settle, then go back in or end the session.

Breaks are built into many sauna routines and research protocols. One study compared two 20-minute sessions split by a 5-minute cooling break with a single 30-minute session.⁹ In a 2005 study, a 15-minute session at 92.3°C was split by two 2-minute showers at 20–22°C.⁸

Be clear on what breaks do and don’t do. A 2017 review suggested short cooling breaks “may maximize benefits” but noted this is not proven.⁹ Think of breaks as a comfort and safety tool, not a shortcut to better results.

Know when to stop

Get out if you feel dizzy, nauseous, or lightheaded.¹ Your body’s signals matter more than the timer.

Don’t worry if you barely sweat

You may not sweat much in your first few sessions.¹ Sweating typically increases as your body gets used to regular heat. Consistency matters more than how drenched you feel on day one.

Cool down gradually

Sit in the sauna with the door open for about five minutes before you stand up and move on.¹ This gives your heart rate and core temperature time to come down.

Rehydrate with at least 24 oz

Sunlighten recommends at least 24 oz of water or an electrolyte drink after each session.¹ Sweat carries electrolytes as well as water, so post-session hydration matters.¹²

Go further: track your sweat rate. Want a personal number? Weigh yourself before and after a session, then add any water you drank.¹⁰ Each pound you lose equals about 16 oz of fluid to replace.¹⁰ The American College of Sports Medicine recommends keeping fluid losses under 2% of your body weight.⁶

Rinse off with a lukewarm shower

Once your core temperature has come down, take a lukewarm shower.¹ Sunlighten advises against cold water right after a session.¹ A rinse also clears sweat and other residues from your skin to prevent reabsorption.

Using your sauna after a workout

If you sauna after training, the research is promising but small. In a 2015 study of 10 active men, 30 minutes of far infrared at 35–50°C after maximal endurance exercise improved jump performance compared with seated rest.¹¹ The same study found no recovery difference after strength training.¹¹ The study was partly funded by sauna maker Harvia.¹¹

Keep your sauna clean

Towels on the bench absorb most sweat and moisture during regular use.² At least every six months, wipe the wood with Sunlighten All Natural Wood Cleaner and the glass with Sunlighten All Natural Glass Cleaner.² Dust the outside with a dry cloth, treat interior stains with light sandpaper, and never use chemical cleaners.² The Natural Sauna Cleaning Kit is available from the Sunlighten Online Store.²

Does more sweat mean a better session?

No. Sweat rate varies from person to person, and it often increases as you use your sauna more regularly.¹ A lighter sweat doesn’t mean the session didn’t work.

Is water always enough?

Sunlighten’s guidance allows water or an electrolyte drink.¹ For longer or more frequent sessions, an electrolyte drink helps replace what you lose in sweat.¹² Your sweat-rate number is the best guide.

Do I have to push through the whole session?

No. Taking a cooling break or ending early is always an option. Listening to your body is part of good sauna practice.¹

• First Timers Guide to Sitting in a Sauna
• Sauna Skin Care Tips
• How to Create Your Own Personal Hydration Plan
• What’s Your Sweat Fingerprint?
• Sauna Contraindications