APStracts 3:0400A, 1996.

Segmental body composition assessed by bioelectrical impedance analysis and dual x-ray absorptiometry in humans. Bracco, David, Daniel Thi[umlaut]abaud, Ren[umlaut]a L. Chiol[umlaut]aro, Michel Landry, Peter Burckhardt, Yves Schutz. Institute of Physiology, Faculty of Medicine, University of Lausanne, Switzerland, Dept. of Surgical Intensive Care, University Hospital, Lausanne, Switzerland, Dept. of Internal Medicine, University Hospital, Lausanne, Switzerland, Dept. of Radiology, University Hospital, Lausanne, Switzerland

APStracts 3:0400A, 1996.

The study assessed the relative contribution of each body segment to whole body FFM and impedance and explored the use of segmental bioelectrical impedance analysis to estimate segmental tissue composition. Multiple frequencies, whole body and segmental impedances were measured in 51 normal and overweight women. Segmental tissue composition was independently assessed by dual X-ray absorptiometry. The sum of the segmental impedance corresponded to the whole body (100.5 0.3% at 50 kHz). The arms and the legs contributed to 47.6% and 43.0% to whole body impedance at 50kHz respectively, whereas they represented only 10.6 and 34.8% of total FFM, as determined by DEXA. The trunk averaged 10.0% of total impedance but represented 48.2% of FFM. For each segment, there was an excellent correlation between the specific impedance index (length2/impedance) and FFM (r = 0.87, r = 0.87, r = 0.86 for the arm, trunk and leg respectively). The specific resistivity was in a similar range for the limbs (arm 159 23, leg 193 39 cm at 50 kHz), but was higher for the trunk (457 71 cm). This study shows the potential interest of segmental body composition by BIA and provides specific segmental body composition equations for use in normal and overweight women.

Received 21 July 1995; accepted in final form 25 June 1996.
APS Manuscript Number A797-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 29 August 1996