Effects of radium hot spring bathing on flow – mediated dilation, physiologic values, and subjective feeling were investigated in healthy adults. Sixteen adults (8 men and 8 women)were subjected to bathing for 20 min and staying in rest until 2 h postbathing. During the period of bathing and postbathing,effects on brachial artery flow – mediated dilation (FMD and vascular diameter),physiologic values,and subjective feeling were measured and analyzed.　Average values of FMD and vascular diameter,7.5±0.8％and0.27±0.03ｍｍ,before bathing increased significantly to 9.3±1.0％and0.35±0.03ｍｍ during 20 min bathing and then these significant increases were sustained for 2 h after bathing, respectively. Subgroup analysis of these changes for men and women revealed that significant increases after bathing were sustained only in a women’s group. The average values of systolic and diastolic blood pressures, body weights, and body fat percentages decreased significantly during bathing and after bathing in comparison with those before bathing, but pulse rates and body temperatures increased significantly only during bathing. Subjective feelings containing cheerfulness, relaxation, and physical activity were measured using

Visual analog scale (VAS) and improvement of them was observed during and after bathing. These results indicate that radium hot spring bathing exerted beneficial effects in increase of flow – mediated dilation, decrease of blood pressure, and improvement of subjective feelings.

Key words:radium hot spring bathing, flow – mediated dilation,FMD, blood pressure, subjective feeling