Effect of Water Temperature on Respiratory Regulation during Head-Out Water Immersion / 日本温泉気候物理医学会雑誌

ABSTRACT

The purpose of this study was to determine the effects of water temperatures on respiratory regulation during head-out water immersion (HWI). A total of eight healthy young male and female subjects were immersed in water at temperatures of 25, 30, 36, 38, 40, and 42°C for 10 minutes, and breathing frequency, tidal volume, ventilation, oxygen consumption, heart rate, and sublingual temperatures were measured over a period of 40 minutes before, during, and after HWI at each water temperature. Both oxygen consumption and ventilation increased during HWI at any temperature. It was hypothesized that the increase in oxygen consumption at 25°C was due to the increase in tidal volume and that at 40 and 42°C was due to the increase in ventilation caused by the increase in breathing frequency. These results suggest that the respiratory regulation during HWI is closely related to the body temperature regulation in response to water temperatures.