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1.4 Bio impedance analysis (BIA)
BIA is the common measurement method among Body Balance body analysis scales. This method does not
directly measure values like body fat, body water, and muscle mass but instead measures the electric resistance
(impedance) of the body. The respective body values are then calculated based on the personal values (body
weight and measured body impedance). The evaluation of the body values is based on a scientific study of a
European reference population group.
The impedance measurement is performed by electrodes located on the platform of the scale. This is done by a
harmless, weak electrical signal, which is send through the body (< 0.1 mA). The electric current is able to flow
better through body fluids (water), which are contained chiefly in the muscles of the human body, than through body
fat. The higher the body‘s resistance against the electric signal, the higher the body fat content and the lower the
body water content. And vice-versa: the higher the muscle mass in percent, the higher the body water content in
percent and the lower the body fat content in percent.
The body water content is grouped in intracellular water (in the cells) and extracellular water (outside of the cells).
1.5 The body mass index (BMI)
The foundation of this calculation is the body mass index - an index number that can be used to interpret body
weight in terms of the risk it poses to your health.
The index number is calculated based on the body weight in kilogram, divided by the body height squared
(example: BMI = = 24.5)
Classification of the body weight based on BMI
(Source: World health organization, 2000)
BMI (kg/m²)
Classification
< 18.5
Underweight
18.5 - 24.9
Normal weight
25.0 - 29.9
Overweight
≥ 30.0
Adiposity
30.0 - 34.9
Adiposity level I
35.0 - 39.9
Adiposity level II
≥ 40.0
Adiposity level III
75 kg
1.75 m x 1.75 m