著者

田中 喜代次 金 憲経 中西 とも子 天貝 均

出版者

日本運動生理学会

雑誌

日本運動生理学雑誌 (ISSN:13403036)

巻号頁・発行日

vol.6, no.1, pp.37-45, 1999-01-30

被引用文献数

14

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The results of early work completed using bioelectrical impedance for body composition assessment was limited by technological problems. Most of the research has focused on bioelectrical impedance conducted at a frequency of 50 kHz. It has been recently determined that low- and high-frequency bioelectrical impedance measurements can be used to distinguish the volume of extracellular water (ECW) from the volume of total body water (TBW). Therefore, a multi-frequency bioelectrical impedance method allows an independent assessment of ECW, TBW, and intracellular water (ICW). Using dual energy X-ray absorptiometry (DXA; Lunar DPX-L) as a reference method, we examined the validity of bone mineral content and bone-free lean tissue mass (LTM) measured by a multi-frequency bioelectrical impedance instrument (MLT-100, Sekisui) using a number of frequencies ranging from 2.5 kHz to 350 kHz applied to the right side of the body. The subjects were 52 men and 109 women, aged 23 to 86 years (men: 53.2±17.37 yr, women: 52.5±17.07 yr). The average LTM determined by DXA were 49.4± 5.92 kg for men and 35.6±4.35 kg for women. Multiple regression equations developed in the present study for estimating LTM were: LTM=0.306X_1+0.003X_2+0.098X_3+3.44 (R=0.948, SEE=1.93 kg) for men LTM=0.169X_1+0.003X_2+0.186X_3+5.75 (R=0.917, SEE=1.76 kg) for women where X_1=Ht^2/R_<HIGH>, X_2=H^3/1000 and X_3=Ht^2/R_<LOW> an R_<HIGH> and R_<LOW> stand for resistance of TBW and resistance of ECW, respectively. These equations may be used to evaluate body composition for a wide range of Japanese adults with reasonable accuracy.