Weissman C, Askanazi J, Rosenbaum S H, Hyman A I, Milic-Emili J, Kinney J M
Clin Sci (Lond). 1986 Nov;71(5):553-8. doi: 10.1042/cs0710553.
Low level exercise is frequently used to assess cardiac and pulmonary function. This study examines the differences in both metabolic and respiratory patterns between the sitting and supine position. Six normal male subjects were studied in both positions during four levels of exercise (12.5, 25, 37.5 and 50 W). Oxygen consumption (VO2), carbon dioxide production (VCO2) and minute ventilation (VE) were greater when sitting as were the ventilatory equivalents to O2 (VE/VO2) and CO2 (VE/VCO2). Respiration was compared at equivalent workloads; the greater minute ventilation observed during sitting was due to greater tidal volumes (VT) and mean inspiratory flows (VT/TI). Expiratory time (TE) was longer and inspiratory duration shorter under most conditions when sitting. When breathing patterns were compared at similar degrees of minute ventilation, VT, TE and VT/TI were greater when sitting, while respiratory frequency (fR) was slower.
低强度运动常用于评估心肺功能。本研究考察了坐姿和仰卧位时代谢和呼吸模式的差异。对6名正常男性受试者在四个运动水平（12.5、25、37.5和50瓦）下的两种体位进行了研究。坐姿时的耗氧量（VO2）、二氧化碳产生量（VCO2）和分钟通气量（VE）以及通气当量（VE/VO2）和二氧化碳通气当量（VE/VCO2）均更高。在同等工作量下对呼吸进行了比较；坐姿时观察到的分钟通气量更大是由于潮气量（VT）和平均吸气流量（VT/TI）更大。在大多数情况下，坐姿时呼气时间（TE）更长，吸气持续时间更短。当在相似的分钟通气量程度下比较呼吸模式时，坐姿时VT、TE和VT/TI更大，而呼吸频率（fR）更慢。
