Effects of procedure, upright equilibrium time, sex and BMI on the precision of body fluid measurements using bioelectrical impedance analysis

摘要: Background/Objectives: Extensive work has addressed the validity of bioimpedance (BIA) measurements and effect posture on fluid homeostasis. However, limited research investigated effects subject preparation. This study aimed to determine precision total body water (TBW) extracellular (ECW) using a stand-on multifrequency BIA (MFBIA seca mBCA 514/515), in three pre-test procedures: supine, sitting, following walking, with specific reference influence sex mass index (BMI). Subjects/Methods: Fifty healthy, ambulatory men (n=26, age:32.5±9.4 years) women (n=27, age:35.2±10.3 received repeat MFBIA (six from 0 15 min). Agreement were evaluated for each condition paired time points. Results: Significant TBW differences supine observed walking (females) sitting (males) postures. For BMI (24.9 kg m−2) significant both ECW also walking. There was no or (25.0 kg m−2) measures. Irrespective BMI, there close agreement over protocols. Conclusions: Practitioners can have confidence within 15 min period pre-testing conditions (supine, walking) healthy subjects, though must be cautious assessments when postures change. Further examine impact procedures measurements, including subjects disturbance, is warranted.