Bioelectrical Impedance Analysis
The MA801 uses Bioelectrical Impedance Analysis (BIA) to determine body composition. At
its core, BIA operates by treating the human body as an electrical conductor within an
alternating current circuit, from which the alternating current resistance and impedance is
measured.
Using a combination of existing population data and in-house research, body composition
analysis formulas can calculate results based on the Impedance, Height, Gender, Age, and
Weight of the subject. These formulas are formulated with reference to gold standard
measurements such as those listed above to confirm viability and accuracy.
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VIII. ABOUT RESULTS
B. Result Sheet Explanation
This section provides an overview of Body Composition and Bioelectrical Impedance
Analysis. For additional information, we recommend the study of relevant medical literature.
Body Composition Analysis
The human body is composed of a variety of elements that can be calculated and
measured separately using a combination of methods. The MA801 uses a 4-compartment
model that divides the body into water, protein, minerals, and fat. Their corresponding
measurement techniques can be found below:
Parameters
Total Body Water (TBW)
Extracellular Water (ECW)
Protein
Minerals
Fat-Free Mass (FFM)
Measurement Technique
Dilution method. Tracer: Deuterium
Dilution method. Tracer: Sodium bromide
Neutron Activation Analysis
Dual Energy X-Ray Absorbtiometry (DXA/DEXA)
Difference between weight and fat mass
Calculated using the 4-compartment model of Body
Composition - Total Body Water, Body Volume, Body Minerals
and Weight
Fat Mass (FM)
The direct measurement of fat mass in particular is technically complex, requiring the
combination of several different parameters. Further details below:
Parameters needed to measure FM
Minerals
Total Body Water (TBW)
Measurement Technique
Dilution method. Tracer: Deuterium
Densitometry - Underwater Weighing (UWW) or
Air Displacement Plethysmography (ADP)
Body Volume
Most of the above "gold standard" techniques are time-consuming, and use specialized
equipment which require trained medical staff to operate. As such, they tend to be
impractical for most facilities.
BIA is non-invasive and safe for all subjects, with the exception of people who have embedded
electronic medical equipment. The accuracy of BIA can be affected by various environmental
and biological factors. For more information on recommended measurement precautions,
please refer to Chapter VI. Instructions for Operation
Dual Energy X-Ray Absorbtiometry (DXA/DEXA)