The estimated bioelectrical impedance of arm, trunk and leg can be used to directly calculate FFM (non-fat mass). Baumgartner and others show that the ratio of trunk reactance to resistance (phase angle) is closely related to %BF (percentage of body fat).
The principle of the human body tester is to measure various indexes of the body through the flow of bioelectricity in the body. Because different tissues of the body, such as muscle and fat, have different resistances to electric current, all indicators should be measured.
Extended data:
The basic component of the human body is cells. Cells are covered by a semipermeable membrane with special structure and function, called cell membrane or plasma membrane, which allows some substances to pass selectively while strictly maintaining the stability of substances in cells. Cell membrane is not only a barrier between cells and the surrounding environment, but also a gateway for cells to accept the influence of the outside world or other cells.
Various physical stimuli in the cell environment, chemical stimuli such as hormones and transmitters produced in the body, and some drugs that enter the human body. Many first act on the cell membrane and then affect various physiological functions in the cell. The nature and changes of cell membrane reflect the physiological and pathological state and changes of human body from the cellular level.
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