The heart in the sauna

What happens to pulse, blood pressure and blood vessels during a SaunaGus, and what the long studies show.

Turban Sauna // Journal

Guests often ask us what the heat does to the heart. Here is what happens during a round, after it, and what the long studies show.

The heat opens the blood vessels

In the sauna your skin warms quickly. To get rid of the heat, the blood vessels in the skin widen and send a large share of your blood out towards the surface. Your skin turns red and warm. To keep blood pressure steady while so much blood sits in the skin, the heart beats faster and pumps more blood with every beat.

What researchers measured

In a German study, researchers measured pulse and blood pressure in 19 healthy adults during 25 minutes in a sauna at 93°C. Both rose steadily throughout the session. The load on the heart matched moderate physical work of 60 to 100 watts on an exercise bike. For a healthy heart that is a manageable load, and it is the reason heat and the heart belong in the same conversation.

After the round, blood pressure falls

Once the participants left the heat, their blood pressure fell below their starting level, and their pulse came down steadily during the rest. That is also why you can feel light-headed when you stand up: some of the blood is still out in the skin and the legs. Stand up calmly and sit for a moment before you walk.

Then the cold

When you go from the heat into the cold plunge, the blood vessels in the skin narrow within seconds, and blood pressure rises briefly. Read more about that reaction in What happens in your body in the cold plunge.

What the long studies show

A Finnish study followed 2,315 men aged 42 to 60 for about 21 years. The men who used the sauna 4 to 7 times a week had about a third of the risk of sudden cardiac death compared with the men who went once a week. In the same group of Finnish men, those who went 4 to 7 times a week had about half the risk of developing high blood pressure.

These are observational studies of Finnish men. They show a link, and the researchers themselves call for trials that can show the cause. People who are healthy may also simply use the sauna more.

Who should talk to a doctor first

Talk to your doctor before your first SaunaGus if you have unstable angina, have recently had a heart attack, have severe narrowing of the aortic valve, often feel dizzy from low blood pressure, or are pregnant. Alcohol before or during the sauna adds strain to the heart and the blood pressure, so save it for later.

Looking after your heart at TURBAN

Drink water before and between rounds, and take the rounds at your own pace. The lower bench is cooler than the top one. If it gets too much, step out and join again at the next round. Read our safety information before your first visit.

Sources

Ketelhut & Ketelhut (2019): The blood pressure and heart rate during sauna bath correspond to cardiac responses during submaximal dynamic exercise

Laukkanen et al. (2015): Association between sauna bathing and fatal cardiovascular and all-cause mortality events

Zaccardi et al. (2017): Sauna bathing and incident hypertension

Laukkanen, Laukkanen & Kunutsor (2018): Cardiovascular and other health benefits of sauna bathing