Leff M L, Hill J O, Yates A A, Cotsonis G A, Heymsfield S B
JPEN J Parenter Enteral Nutr. 1987 Jul-Aug;11(4):354-9. doi: 10.1177/0148607187011004354.
Resting metabolic rate (RMR) usually is measured by indirect calorimetry for a brief interval, and the results are then extrapolated to 24-hr resting energy production. The aim of the current study was to examine the validity of this approach by measuring the within- and between-day variability in RMR. The RMR was measured hourly in 14 healthy adults from 8:00 am to 4:00 pm after an overnight fast on two separate days. The results indicated that, during day 1, RMR remained unchanged from early morning to late afternoon, and there was no significant difference between RMR measurements 1 through 8. Based upon analysis of variance and intraclass correlation coefficients, the averages of the first and the last three RMR measurements were found to be unreliable. RMR reliability was improved by averaging all measurements taken during the day, and maximum reliability was obtained by averaging the middle three RMR measurements. A similar pattern of results was observed during day 2, although the overall trend was for the reliability of RMR measurements to improve relative to day 1. The average RMRs on days 1 and 2 were not significantly different. These results indicate that the current practice of establishing a patient's RMR based upon a single measurement potentially can lead to large errors in determining energy needs. Measurement reliability can be improved by serially measuring RMR, eliminating the initial measurement, and averaging the remaining two to three values.
静息代谢率（RMR）通常通过间接测热法在短时间内进行测量，然后将结果外推至24小时静息能量产生量。本研究的目的是通过测量RMR的日内和日间变异性来检验这种方法的有效性。在两个不同的日子里，14名健康成年人在禁食过夜后，于上午8点至下午4点每小时测量一次RMR。结果表明，在第一天，从清晨到傍晚RMR保持不变，第1次至第8次RMR测量之间没有显著差异。基于方差分析和组内相关系数，发现第一次和最后三次RMR测量的平均值不可靠。通过对一天中所有测量值求平均值提高了RMR的可靠性，对中间三次RMR测量值求平均值获得了最大可靠性。在第二天观察到了类似的结果模式，尽管总体趋势是RMR测量的可靠性相对于第一天有所提高。第一天和第二天的平均RMR没有显著差异。这些结果表明，目前基于单次测量确定患者RMR的做法可能会在确定能量需求时导致较大误差。通过连续测量RMR、排除首次测量值并对其余两到三个值求平均值，可以提高测量的可靠性。
