To test the hypothesis that mist sauna is a safer way of bathing than dry sauna, we compared changes in circulatory and thermoregulatory functions during 10 min sauna bathing in mist sauna at 40℃ with relative humidi...To test the hypothesis that mist sauna is a safer way of bathing than dry sauna, we compared changes in circulatory and thermoregulatory functions during 10 min sauna bathing in mist sauna at 40℃ with relative humidity of 100%, and in dry sauna by infrared ray at 70℃ with relative humidity of 15%. Subjects were seven healthy young men aged 29 ± 6 yrs (mean ± SD). We measured blood pressure, heart rate, skin temperatures at chest, forearm, thigh, and leg, tympanic temperature (Tty) by thermistors, skin blood flow at forearm by laser Doppler flowmetry, and sweat rate by ventilated capsule method at 1 min intervals throughout the experiment. Total sweating and change of hematocrit were also measured for dehydration analysis. Blood pressure was elevated more and changes in heart rate and total sweating were larger in dry sauna than mist. A significant hematocrit increase was observed in dry sauna bathing only. Mean skin temperature and Tty in dry sauna were elevated higher than those in mist. Heat stress of the dry sauna may be stronger than that of the mist, leading to dehydration and hypovolemia by sweating. Percent plasma volume loss was significantly larger in the dry than mist sauna. Changes in skin blood flow and sweat rate/Tty during mist sauna were significantly larger than those during dry sauna bathing despite heat stress of the mist sauna. The mist sauna bathing may thus be safer physiologically, and provide more effective vascular dilatation and sweating than the dry sauna bathing.展开更多
Physicians often observe patients’ complexion (their natural skin color) as an indicator of health. The complexion may depend on the internal environment, however, very few researchers studied its evidence. We previo...Physicians often observe patients’ complexion (their natural skin color) as an indicator of health. The complexion may depend on the internal environment, however, very few researchers studied its evidence. We previously reported various benefits of a mild hyperthermia treatment on human health using the nano-mist sauna (NMS), including acceleration of gas exchange (O2 and CO2) in the venous blood, enhancement of immunity, and the modulation of autonomic nervous system. However, the effects of NMS on skin appearance are unknown. There is a historical and widespread belief that mild hyperthermic treatments such as hot springs are good for improving skin appearance. However, the effect of NMS on the skin appearance has not been examined. In the present study, we examined the color of venous blood using the CIELAB (a color space specified by the French Commission internationale de l’éclairage) method, and then compared the color changes before and after NMS stimulation. Next, we examined correlations of blood gas parameters with color elements of the venous blood, which are highly dependent on oxygen. Our results suggest that the colors and appearance of the face depend on the internal environment, because there are numerous vessels under the skin. Thus, the color of the venous blood may provide medical evidence of changes in complexion. This new method may be useful for assessment of medical complexion by physicians, for use in determining internal health based on skin color information.展开更多
文摘To test the hypothesis that mist sauna is a safer way of bathing than dry sauna, we compared changes in circulatory and thermoregulatory functions during 10 min sauna bathing in mist sauna at 40℃ with relative humidity of 100%, and in dry sauna by infrared ray at 70℃ with relative humidity of 15%. Subjects were seven healthy young men aged 29 ± 6 yrs (mean ± SD). We measured blood pressure, heart rate, skin temperatures at chest, forearm, thigh, and leg, tympanic temperature (Tty) by thermistors, skin blood flow at forearm by laser Doppler flowmetry, and sweat rate by ventilated capsule method at 1 min intervals throughout the experiment. Total sweating and change of hematocrit were also measured for dehydration analysis. Blood pressure was elevated more and changes in heart rate and total sweating were larger in dry sauna than mist. A significant hematocrit increase was observed in dry sauna bathing only. Mean skin temperature and Tty in dry sauna were elevated higher than those in mist. Heat stress of the dry sauna may be stronger than that of the mist, leading to dehydration and hypovolemia by sweating. Percent plasma volume loss was significantly larger in the dry than mist sauna. Changes in skin blood flow and sweat rate/Tty during mist sauna were significantly larger than those during dry sauna bathing despite heat stress of the mist sauna. The mist sauna bathing may thus be safer physiologically, and provide more effective vascular dilatation and sweating than the dry sauna bathing.
文摘Physicians often observe patients’ complexion (their natural skin color) as an indicator of health. The complexion may depend on the internal environment, however, very few researchers studied its evidence. We previously reported various benefits of a mild hyperthermia treatment on human health using the nano-mist sauna (NMS), including acceleration of gas exchange (O2 and CO2) in the venous blood, enhancement of immunity, and the modulation of autonomic nervous system. However, the effects of NMS on skin appearance are unknown. There is a historical and widespread belief that mild hyperthermic treatments such as hot springs are good for improving skin appearance. However, the effect of NMS on the skin appearance has not been examined. In the present study, we examined the color of venous blood using the CIELAB (a color space specified by the French Commission internationale de l’éclairage) method, and then compared the color changes before and after NMS stimulation. Next, we examined correlations of blood gas parameters with color elements of the venous blood, which are highly dependent on oxygen. Our results suggest that the colors and appearance of the face depend on the internal environment, because there are numerous vessels under the skin. Thus, the color of the venous blood may provide medical evidence of changes in complexion. This new method may be useful for assessment of medical complexion by physicians, for use in determining internal health based on skin color information.
