| 摘要 |
A system for the accurate determination of human body composition comprises the measurement of the conductive potential of the body, which is directly related to the lean tissue content, using electrodes and an impedance bridge circuit. Measurements of body impedance are made over two different frequency ranges in order to distinguish between intra-cellular body cell mass and extra-cellular body mass, and furthermore both total body impedance and segmental impedance measurements are made, in order to predict distribution and changes in total body water. Electrodes are placed in a tetra-polar arrangement for the total body measurement and on anatomical extremes (e.g. arm, leg) for the segmental measurements. The resultant "bio-impedance signal" (three digit number, between 1 and 1000 ohms) is entered into modifying means to predict the body composition of the tested individual. The modifying component, in one embodiment, comprises prediction formulae derived from biological data inputs, including a patient's height, weight, age, and sex, to determine a "population prediction variable", and therefore interpreting the bio-impedance readings as "population specific". This specificity is related to morph-type, leanness, body water and age. |
