Van Loan M D
US Department of Agriculture, Western Human Nutrition Research Center, San Francisco, CA 94129.
Am J Clin Nutr. 1990 Oct;52(4):586-90. doi: 10.1093/ajcn/52.4.586.
The accuracy of total-body electrical conductivity (TOBEC) for body composition assessment was examined in 50 teen-agers (33 males and 17 females) aged 11-19 y. Body composition measures included densitometry, hydrometry, bone mineral density of the one-third distal radius, and TOBEC. Fat-free mass (FFM) was calculated by using one-, two-, and three-compartment models: densitometry, FFMd; densitometry and hydrometry, FFMdw; and densitometry, hydrometry, and bone mineral density, FFMdwb. Correlations between TOBEC variables and the three calculations of FFM were highly significant (r = 0.88-0.95; P less than 0.01). No significant differences were observed (ANOVA) between the TOBEC estimate of FFM (FFMT) and FFMd, FFMdw, and FFMdwb. Similar results were observed when the data were analyzed by gender. The TOBEC estimate of FFM was equivalent to the estimates of FFM derived from one-, two-, and three-component models. Its ease of measurement and its prediction accuracy (R2 = 0.933; SEE = 2.45 kg) in teen-agers make it a preferred technique for body composition assessment.
对50名年龄在11至19岁的青少年（33名男性和17名女性）进行了全身电阻抗（TOBEC）评估身体成分准确性的研究。身体成分测量包括密度测定法、体液测定法、桡骨远端三分之一处的骨矿物质密度以及TOBEC。无脂肪量（FFM）通过单室、双室和三室模型计算得出：密度测定法，FFMd；密度测定法和体液测定法，FFMdw；密度测定法、体液测定法和骨矿物质密度，FFMdwb。TOBEC变量与FFM的三种计算方法之间的相关性非常显著（r = 0.88 - 0.95；P < 0.01）。在FFM的TOBEC估计值（FFMT）与FFMd、FFMdw和FFMdwb之间未观察到显著差异（方差分析）。按性别分析数据时也观察到类似结果。FFM的TOBEC估计值等同于从单室、双室和三室模型得出的FFM估计值。其在青少年中易于测量且预测准确性高（R2 = 0.933；SEE = 2.45 kg），使其成为身体成分评估的首选技术。
