The consideration of melatonin concentration and subjective evaluation in the various bathing methods

In Japan, evening bathing as a means of both cleaning and relaxation has been a well-established custom from ancient times. The effects of bathing, its environment, the method of bathing, the time of day and similar details have been studied extensively in Japan. For example, Lee et al. [1] reported that both a full immersion bath and a mist sauna are effective in facilitating recovery from muscle fatigue. Sauna therapy was shown to improve the cardiac index, mean pulmonary wedge pressure, systemic and pulmonary vascular resistance, and cardiac function [2]. Furthermore, Hashiguchi et al. [3] reported that after bathing, low relative humidity and high air velocity have negative effects on humans, i.e., a decrease in body temperature and dryness of the skin and eyes.