title: Accuracy of plantar electrodes compared with hand and foot electrodes in fat-free-mass measurement.
abstract: This paper investigates the measurement of fat-free mass (FFM) by bioimpedance using foot-to-foot impedancemeters (FFI) with plantar electrodes measuring the foot-to-foot resistance R34 and hand-to-foot medical impedancemeters. FFM measurements were compared with corresponding data using Dual X-ray absorptiometry (DXA). Equations giving FFM were established using linear multiple regression on DXA data in a first group of 170 subjects. For validation, these equations were used on a second group of 86 subjects, and FFM were compared with DXA data; no significant difference was observed. The same protocol was repeated, but using electrodes on the right hand and foot in standing position to measure the hand to-foot resistance R13. Mean differences with DXA were higher for R13 than for R34. Effect of electrode size and feet position on resistance was also investigated. R34 decreased when electrode area increased or if feet were moved forward. It decreased if feet were moved backward. A proper configuration of contact electrodes can improve measurement accuracy and reproducibility of FFI.
authors.affiliation: Department of Biological Engineering, Technological University of Compiegne, UMR CNRS 7338, Compiegne Cedex, France.
authors.forename: Michel Y
authors.initials: MY
authors.lastname: Jaffrin
authors.affiliation: Department of Biological Engineering, Technological University of Compiegne, UMR CNRS 7338, Compiegne Cedex, France.
authors.forename: Sana
authors.initials: S
authors.lastname: Bousbiat
mesh_terms: D000328:Adult; D000368:Aged; D001823:Body Composition / Q000502:physiology*; D001834:Body Water; D001837:Body Weights and Measures / Q000295:instrumentation* / Q000379:methods; D017097:Electric Impedance; D004566:Electrodes; D004867:Equipment Design; D005260:Female; D005528:Foot / Q000502:physiology*; D006225:Hand / Q000502:physiology*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: bioimpedance; body composition; electrode design; foot-to-foot impedancemeter