Validity of fan-beam dual-energy X-ray absorptiometry for measuring fat-free mass and leg muscle mass

Abstract

The aim of the study was to examine the accuracy of fan-beam dual-energy X-ray absorptiometry (DEXA) for measuring total body fat-free mass (FFM) and leg muscle mass (MM) in elderly persons. Participants were 60 men and women aged 70-79 yr and with a body mass index of 17.5-39.8 kg/m(2). FFM and MM at four leg regions were measured by using DEXA (Hologic 4500A, v8.21). A four-compartment body composition model (4C) and multislice computed tomography (CT) of the legs were used as the criterion methods for FFM and MM, respectively. FFM by DEXA was positively associated with FFM by 4C (R(2) = 0.98, SE of estimate = 1.6 kg). FFM by DEXA was higher [53.5 +/- 12.0 (SD) kg] than FFM by 4C (51.6 +/- 11.9 kg; P < 0.001). No association was observed between the difference and the mean of the two methods. MM by DEXA was positively associated with CT at all four leg regions (R(2) = 0.86-0.96). MM by DEXA was higher than by CT in three regions. The results of this study suggest that fan-beam DEXA offers considerable promise for the measurement of total body FFM and leg MM in elderly persons.

Accelerated Loss of Skeletal Muscle Strength in Older Adults With Type 2 Diabetes

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Estimación de la Masa Muscular de los Miembros Apendiculares, a Partir de Densitometría Fotónica Dual (DEXA)

“…Kim et al, fueron capaces de estimar la masa muscular total por medio del método DEXA (Kim et al, 2002(Kim et al, , 2004Shih et al, 2000;Levine et al, 2000;Visser et al, 1999), pero no consiguieron dividir este compartimiento por segmentos corporales. Por este motivo, el desarrollo del método antropométrico de fraccionamiento por regiones y validado por DEXA, permitiría realizar comparaciones específicas entre la manera en que se distribuyen los tejidos (Lohman & Chen, 2005), y su influencia en el rendimiento físico, como la masas grasa y muscular, de acuerdo a la actividad deportiva que realiza cada individuo, teniendo de este modo información de la distribución y desarrollo físico diferenciado, que el simple análisis de la totalidad de cada componente de la composición corporal, no es capaz de proporcionar.…”

Densidade mineral óssea e absortometria de raio-x de dupla energia

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