Brain Sleep Inc. has conducted a study on the effects of sauna bathing on sleep in cooperation with Kyoritsu Maintenance Corporation, which operates the “Dormy Inn” business hotel, 100plus Inc. The results of this study showed that sauna bathing is effective in improving sleep. The results showed that taking a sauna bath in addition to taking a bath before bedtime tended to improve the duration of sound sleep and the degree of sound sleep in the first cycle, which plays the most important role in sleep quality, compared to taking a bath alone.
■Contents and Results of the Verification
In this study, the effects of taking a sauna bath in addition to taking a bath on sleep were examined. 9 subjects in their 20s to 60s were measured and compared their sleep state after taking a bath only and after taking a bath plus a sauna bath.
Sleep state was evaluated using an activity meter, an autonomic neuropathometer, and an electroencephalograph as objective indices, and a questionnaire using the VAS (Visual Analogue Scale) method as a subjective index.
The results suggested that sauna bathing may lead to the following improvements in sleep quality.
①Significant improvement in sleep latency and wake-up latency, which indicate the quality of falling asleep and waking up.
②An improvement in the duration of sound sleep and the degree of sound sleep during the most important first 90 minutes of sleep (the first sleep cycle)
③Relaxation, reduced fatigue, feeling refreshed upon awakening, and feeling energized after waking up