Zusammenfassung

Objective: While supine position is the classical method to measure resting metabolic rate (RMR), the effects of postural changes on RMR is not clear. The aim of this study is to examine the effect of postural changes on RMR and substrate utilization. Material and Methods: RMR was measured in 23 sedentary male subjects (age: 26.7±5.8 yr) after an overnight fast for 10 min in random order for supine, sitting and standing positions. An automated gas analysis system was used to measure oxygen consumption (VO2), carbon dioxide production (VCO2), minute ventilation (VE), and heart rate (HR) to determine RMR. RMR was calculated with Weir’s formula, whereas rates of carbohydrate (CHO) and free fatty acid (FFA) utilization were calculated with Frayn’s formula. One way ANOVA with Bonferroni post hoc test was used to calculate the effect of postural changes on variables, and one sample t-Test was used to identify the difference between resting VO2 and 1 MET levels. Results: RMR values measured in supine and sitting positions were similar, both of which were significantly lower than those measured in the standing position (p