Need another reason to relax in a sauna? Research shows that 15-minute sauna sessions not only improve heart function in people suffering from chronic heart failure, but also actually help the heart repair itself.

In a study published in January 2012 in the American Journal of Cardiology, 42 people with chronic heart failure (CHF) sat in saunas for 15 minutes five times per week for three weeks. Following the sauna sessions, the study participants had an increase in blood flow and in the distance they could walk during a six-minute period. 

The saunas also improved function of the participants’ endothelium—the membrane that lines the inside of the heart and controls blood vessel constriction and dilation. This is significant because it indicates that the sauna treatments triggered the study participants’ hearts to repair and heal.

These benefits coincide with previous studies showing that saunas benefit heart function.

A 2002 study published in the Journal of the American College of Cardiology reported that two weeks of sauna therapy improved symptoms in 17 out of 20 heart failure patients, while no improvement was seen in the group that did not use saunas. 

A 2004 study published in the journal Circulation demonstrated that sauna treatments reduced the number of premature ventricular contractions (abnormal heartbeats) in CHF patients from over 3,000 per day to 850. And a larger and longer study published in 2008 in the Journal of Cardiology that featured 188 CHF patients showed that those who used saunas had significant improvement in several key measures of heart function.

The Journal of Cardiology also published a five-year clinical trial in April 2009 showing the heart-health benefits of saunas. In this study, 64 of 129 patients with CHF took a week’s worth of daily saunas, and then continued sauna treatments at least twice a week after they were discharged from the hospital. Five years later, the sauna group was less than half as likely to have died or been rehospitalized than the study participants who didn’t use saunas.

In all these studies, a sauna session consisted of 15 minutes in a far-infrared sauna heated to 60 degrees Celsius. Immediately afterward, study participants lay flat for 30 minutes, covered with a blanket to stay warm. 

No negative impacts have been reported in any of these studies involving sauna treatment.