Biospace inbody s10, User Manual

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1. More about the InBody S10
A. How does BIA work?
The Bioelectrical Impedance Analysis (BIA) method is based on the fact that the human
body consists of conductors and non-conductors. Generally, 50~70% of the human body
consists of water which functions as a conductor, whereas body fat functions as a non-
conductor.
The classic BIA method measures the impedance of the whole body on the assumption that
the human body can be considered a cylinder for the application of this model. If A is the
cross sectional area, and L is the length, the impedance of the cylinder can be expressed as
follows.
If both sides are multiplied by L, We get the new expression as follows.
According to this expression, if we know the L and the impedance value, we get the volume.
That is to say, if we know the height of the human body (acting as a conductor), and know
the impedance value, we can get the volume of body water. Here, the volume represents
examinee’s height. Therefore, the two directly used variables in body composition analysis
are impedance and height.
The principle of the InBody S10’s body composition analysis is explained by the following;
the volume of body water, an electrolyte, is calculated first with a measured impedance
value. Then, we can get the value of fat free mass using the volume of body water. Body fat
mass is determined by deducting the lean body mass from the measured weight.
Height should be entered by the user. Weight can be directly measured on the InBody S10.