Sauna and heart failure: a small pilot in a common type
Eighteen people with a common type of heart failure took a supervised sauna twice a week for ten weeks. They could exercise longer, but the gains faded after they stopped.
Worth knowing: Published in 2026. Letters in the same journal have debated how much a pilot of this size can show.
The short version
SAUNA-HFpEF tested supervised sauna in 18 people with heart failure with preserved ejection fraction, a common type with few treatments that help exercise. They took a 60°C sauna twice a week for ten weeks, building from 8 to 15 minutes. Peak oxygen uptake and walking distance improved, as did leg strength and some quality-of-life scores, and there were no adverse events. Three months after stopping, the fitness gains had declined. With no comparison group and 18 people, it shows sauna was safe and doable here, not that it works.
Keep in mind
No comparison group and 18 people: it shows the sauna was safe and doable under supervision, not that it caused the improvements.
What they found
Eighteen patients completed the study. They attended 97% of sessions, and there were no adverse events.
Peak oxygen uptake rose from 18.2 to 20.6 mL/kg/min, and the six-minute walk from 494 to 527 meters. Leg strength, a measure of heart filling, a depression score and social functioning also improved.
Three months after the sauna stopped, peak oxygen uptake had declined again. Body fat kept falling.
What this means for your practice
If you have heart failure, this is not a reason to start sauna on your own. The sessions here were short, mild and supervised. Talk to your heart team first.
This does not establish a sauna routine to follow.
Methods and limitations
What the researchers did
The researchers invited stable outpatients with heart failure with preserved ejection fraction (HFpEF), a type in which the heart pumps normally but is stiff, and exercise capacity is often poor.
Participants took a supervised sauna at 60°C twice a week for ten weeks, starting at 8 minutes and building to 15. Blood pressure and heart rate were checked three times each session.
Everyone was tested before, at the end, and three months after stopping: an exercise test, a six-minute walk, leg strength, heart ultrasound, questionnaires and muscle biopsies. There was no group that did not take a sauna.
How much can this tell us?
This is a pilot: it asks whether a treatment is safe and practical enough to test properly. For that question, the answer here is encouraging.
Without a comparison group, the improvements cannot be put down to the sauna. Extra attention, regular visits and the chance to rest in company can all help people with heart failure feel and do better.
Unlike most earlier heat studies in heart failure, which used infrared therapy in Japan, this used a sauna, at a mild 60°C. The researchers say a larger randomized trial is being planned.
What makes it useful
- Supervised, with blood pressure checked every session
- Good attendance and no adverse events
- Measured again three months after stopping
What limits it
- No comparison group
- Small: 18 people completed it
- Short sessions at a mild 60°C, under supervision
Where this study fits
Where this study fits
We score claims, not single studies. This one is part of the evidence for:
Heat therapy helps people with heart failure. Some support
Low certaintySize not reportedBody signals
Read the original
Bekfani T, Abo Hwach A, Moebert R, Seibel S, Burger A, Kaehne T, et al. Effects of Sauna bathing on Exercise Capacity and Muscle Function in HFpEF. Eur J Heart Fail. 2026. doi:10.1093/ejhf/xuag082.
DOI 10.1093/ejhf/xuag082 · PubMed 41831305