Impacts of barometric pressure on metabolic rate: A plateau experimental study

Abstract

Metabolic rate is a fundamental parameter influencing thermal comfort, which further affects the well-being and productivity of the occupants. Here, the impacts of barometric pressure on respiratory parameters, metabolic rate, heart rate, and blood oxygen saturation are studied through pressure chamber experiments. The results indicate that the minute ventilation of the subject rises significantly with declining barometric pressures, and usually, this is accomplished by increasing respiratory depth rather than breathing frequency. When the barometric pressure declines from 72.1 kPa to 66.2 kPa, the metabolic rate of subjects at sitting and 1, 2, 3, and 4 km/h walking activities rises by 4.8 %, 7.2 %, 3.5 %, 2.5 %, and 4.3 %, respectively. As the barometric pressure decreases further to 61.9 kPa, the metabolic rate rises again by 3.0 %, 9.8 %, 6.4 %, 5.0 %, and 2.4 %, respectively. In addition, there is often a risk of overestimation when using the heart rate to estimate the metabolic rate at high altitudes, thus this method should be used cautiously. The results are significant in laying the groundwork for elucidating the relationship between metabolic rate and barometric pressure. Further, it is essential for the establishment of thermal comfort standards at high altitudes.