已报道的在腕和踝之间测量阻抗是一种简单、无损的测定人体总含水量及其变化的技术。一些研究人员已经使用多频或扫频的方法,来确定总含水量和细胞外含水量。使用多频方法来确定细胞外含水量是基于细胞膜在低频时具有高阻抗这种性质,在低频情况下,电流主要在细胞外空间通过。尽管细胞外含水量和人体总含水量之间的差别在理 It has been reported that measuring impedance between the wrist and the ankle is a simple, nondestructive technique for determining total body water content and its changes. Some researchers have used multiple or swept methods to determine total and extracellular water content. The use of multifrequency methods to determine the extracellular water content is based on the property that the cell membrane has a high impedance at low frequencies and that the current mainly passes in the extracellular space at low frequencies. Although the difference between extracellular water content and total body water content is reasonable