¹Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, USA

Correspondence: Dr EM Evans, Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, 352 Freer Hall, MC-052, 906 S. Goodwin Avenue, Urbana, IL 61801, USA. E-mail: elevans@illinois.edu

Received 21 January 2009; Revised 3 August 2009; Accepted 5 August 2009; Published online 11 November 2009.

Abstract

The objective of this study was to explore the accuracy of summing multiple dual-energy X-ray absorptiometry (DXA) scans to estimate whole-body soft tissue measures and the sarcopenic index in female subjects for application to an obese population. Forty-five women who fit within the DXA scanning region (Ms.d.; BMI=24.54.6 kg/m²) were scanned four times (one normal whole body (WB) scan, one head/trunk/leg scan allowing trunk delineation (TRK–H–L), one scan with body shifted right (LA) and one left (RA) to allow arm delineation). Fat mass (FM) and appendicular lean mass were determined from the WB scan (aLM_WB), with the latter determined by summing arm and leg mineral-free lean mass (MFLM). Strong agreement and no differences (Ms.d._DIFF) were found between FM_WB and FM_SUM (–0.120.38 kg, P=0.37; r=0.999, P<0.001); MFLM_WB and MFLM_SUM (0.020.36 kg, P=0.80; r=0.998, P<0.001); and aLM_WB and aLM_SUM (0.120.32 kg, P=0.63; r=0.994, P<0.001). Summing DXA scans is a valid method for determining the risk for sarcopenic obesity and may aid research regarding obesity and risk for disability.