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XII. FREQUENTLY ASKED QUESTIONS(FAQ)
A. Regarding Bioelectrical Impedance Analysis
If you have any questions about the MA601 relating to scientific basis not addressed in the
FAQ, please contact us at the following E-mail address: [email protected]
1. How are Body Composition results measured?
Bioelectrical Impedance Analysis (BIA) is a non-invasive measurement of body
composition, based on the fact that the human body consists of conductors and
non-conductors. Water (which comprises a significant proportion of muscle) is a good
conductor of electricity, where fat is a non-conductor. A small, safe, electric current (AC)
is sent through the subject's body. It measures the different levels of resistance
(impedance) as it passes through different types of body tissue. These impedance
values are then translated using clinically validated algorithms into estimations of water,
protein minerals, muscle, and fat. With multiple frequencies, more detailed information -
such as water inside and outside cells - can be analyzed. Each BIA device and brand
uses a different set of algorithms, which is why measurement results may differ when
using different devices.
The most common validation of accuracy is with DEXA, though other methods such as
MRI and CT are used in some studies. The most appropriate validation standard
depends upon what type of composition is measured.
2. Is BIA safe for everyone?
Individuals with implanted medical devices such as pacemakers, defibrillators, or other
internal medical devices should not use BIA machines. A low level electrical current is
sent through the body during measurement, which may have a potentially disruptive
effect on the implanted device.
In addition, BIA measurements can be conducted for the following populations, but there
may be difficulties in measurement and drop in result accuracy:
■ Individuals that are outside the permissible range of measurements (above 300kg)
may receive less accurate results, due to insufficient research data.
■ Women undergo a wide range of body composition changes during pregnancy,
including but not limited to change in fat percentage and body water, which can affect
the accuracy of BIA results.
■ Individuals who cannot hold onto the hand electrodes during testing may find it difficult
to complete measurements.
■ Individuals with prosthetics/amputations cannot complete measurements, as BIA
requires contact with all 8 electrodes (2 for each hand and 2 for each foot).
