A gym sauna session is straightforward: shower first, sit on a towel, stay for 5 to 20 minutes, hydrate generously, and cool down before going about your day. Most gym saunas are dry saunas kept between 150°F and 195°F, and the biggest mistakes people make are staying too long, not drinking enough water, and skipping the cool-down. Here’s how to do it right from your first session.
How Long to Stay In
If you’ve never used a sauna, start with 5 to 10 minutes. That’s enough to raise your core temperature and start sweating without overwhelming your body. As you get comfortable over several sessions, you can work up to 15 or 20 minutes. UCLA Health recommends capping sessions at 20 minutes, and even experienced sauna users rarely need more than 30 minutes at a time.
The key variable is how you feel. If you notice dizziness, nausea, or a pounding headache, leave immediately. These are signs of overheating, not toughness milestones. You can always step out, cool off for a few minutes, and go back in for a second round if you want more time. Breaking your session into two shorter rounds with a 5-minute cool-down in between is a common and effective approach.
Before or After Your Workout
Use the sauna after your workout, not before. Post-exercise sauna use has the strongest research behind it. A controlled trial published in the journal Complementary Therapies in Medicine found that adding just 15 minutes of sauna time after each workout, three times a week for eight weeks, produced measurable improvements over exercise alone: cardiorespiratory fitness increased by an additional 2.7 mL/kg/min, systolic blood pressure dropped an extra 8 mmHg (nearly an entire blood pressure category), and total cholesterol fell by 19 mg/dL more than in the exercise-only group.
Using a sauna before lifting or cardio is counterproductive. It raises your heart rate, depletes fluids, and loosens muscles in ways that can reduce your performance and make you more prone to dehydration mid-workout. Save it for after.
Hydration Makes or Breaks It
You lose a surprising amount of water in a sauna session. A practical target is at least 16 ounces of water for every 10 minutes you spend inside. You can drink before, during, or after, but the total volume matters. A 15-minute session means roughly 24 ounces of fluid on top of whatever you’d normally drink.
Plain water works, but you’re also losing electrolytes through sweat. Adding a pinch of sea salt to your water, or drinking a beverage with electrolytes, helps replace sodium and other minerals. This is especially important if you’ve already sweated heavily during your workout. Alcohol is a hard no: drinking before or during sauna use increases the risk of dangerous drops in blood pressure, irregular heart rhythms, and in rare cases, sudden cardiac events.
What to Wear and Bring
Most gym saunas require a swimsuit or shorts. Wear as little as your gym’s rules allow, since clothing traps heat against your skin and can feel suffocating. Avoid anything with metal zippers or buttons, which heat up fast and can burn. Leave jewelry in your locker for the same reason.
Bring two towels: one to sit on (this is non-negotiable for hygiene and bench protection) and one to wipe sweat. Wear flip-flops to and from the sauna. Gym sauna floors stay warm and wet, which is a perfect environment for athlete’s foot and other fungal infections. Flip-flops also help with traction on slippery surfaces.
Leave your phone and electronics outside. Sustained heat above 113°F damages batteries and screens, and gym saunas run well above that. Smartwatches tend to survive because your body absorbs some heat away from the device, but they’ll still degrade over time with repeated exposure.
Step-by-Step Session
A complete sauna session has three phases: preparation, heat exposure, and cool-down.
- Shower first. A quick rinse removes sweat, lotion, deodorant, and gym grime. This keeps the sauna cleaner for everyone and opens your pores so you start sweating more efficiently.
- Enter and sit on your towel. The upper benches are hotter because heat rises. If you’re new, sit on a lower bench. Set a timer on a clock outside (not your phone inside) or use the sauna’s built-in timer if it has one.
- Breathe normally and stay still. There’s no need to do stretches or exercises inside. Sit or recline, breathe through your nose, and let the heat do its work.
- Exit and cool down gradually. Step out, sit somewhere at room temperature for 5 minutes, and let your heart rate come down. A lukewarm shower works well. Cold water is fine if you’re comfortable with it, and alternating between heat and cold exposure can amplify some metabolic benefits.
- Rehydrate. Drink your 16-plus ounces of water or an electrolyte drink before you leave the gym.
Sauna Etiquette in a Gym Setting
Gym saunas are shared spaces, and the unwritten rules are simple. Keep your voice low or stay silent. Many people use sauna time for quiet relaxation or low-grade meditation, and loud conversations change the atmosphere for everyone. If you’re in there with a friend, a quiet chat is fine, but read the room.
Don’t sprawl across an entire bench when others are waiting for space. Sit upright and keep your towel footprint compact. Never shave, apply lotions, or use oils in the sauna. These products evaporate in the heat and create unpleasant or potentially irritating fumes in an enclosed space. Save all grooming for the shower area afterward.
Health Benefits Over Time
Occasional sauna use feels good. Regular sauna use changes your cardiovascular profile. The same trial that measured post-workout sauna effects found that consistent use (three sessions per week for eight weeks) significantly improved the body’s ability to use oxygen during exercise, lowered resting blood pressure, and reduced total cholesterol. These aren’t small effects. An 8 mmHg drop in systolic blood pressure is comparable to what some people achieve with early-stage lifestyle interventions like dietary changes.
Heat exposure also increases blood flow to muscles, which can ease soreness after heavy training. Your blood vessels dilate in response to the heat, improving circulation in a way similar to light aerobic activity. This is why many athletes use saunas as a recovery tool on training days.
Who Should Be Cautious
Sauna use is safe for most healthy adults, including during uncomplicated pregnancies (contrary to a common myth). However, people with unstable chest pain, a recent heart attack, or severe narrowing of the aortic valve should avoid saunas entirely. If you have a heart condition that’s well-managed, talk to your cardiologist before making sauna use a regular habit.
The most common problems in saunas come from dehydration and alcohol, not from the heat itself. Very few acute cardiac events happen in saunas, and the ones that do are strongly linked to drinking alcohol during or just before a session. Stay hydrated, skip the drinks, and listen to your body when it tells you it’s had enough.