Sauna bathing is a popular, low-cost, and easily accessible type of whole-body thermotherapy that has been used for social, religious, health, and hygienic reasons for thousands of years. There is strong evidence to support the various physiological and psychological benefits of sauna bathing. The positive effects of regular sauna use have been explained by a number of mechanisms of action, including increased cardiac output, reduced peripheral vascular resistance and other physiological changes in cardiovascular parameters such as decreased systolic and/or diastolic blood pressure. Additionally, the psychological impact of sauna bathing may occur due to a combination of factors that include the release of endorphins, relaxation, placebo effects, and psychological and social interactions that likely occur around frequent sauna activity. Taken together, it is possible that acute and regular sauna bathing may impact sleep quality.

Inclusion Criteria:

• good general health assessed by physician
• written consent to participate

Exclusion Criteria:

• medication or dietary supplements, which could potentially impact the study outcomes
• history of sleep or neurological disorders
• regular sauna use
• professional athlete
• shift worker