The present invention concerns an assembly for determining bio-impedentiometric sequential values of (R, Z, Xc, Phase φ), in particular impedance Z, resistance R, reactance Xc, of segments of the body under observation from which to obtain the bioelectric volume or impedance index of each segment or a form correction factor (K), of a conductor, for example a human body, and comprising: First means (1, 2, 4) for injecting a first current (Ii) in the body Second means (3, 10, 15, 16) for detecting a voltage drop following the injection of the first current (Ii) Said second means comprising a device (10 200) having at least a part thereof (12 220) of conducting material in such a way as to detect said voltage drop when said part (12 220) of conducting material results to be in contact with said body. In accordance with the invention, the device (10 200) is configured to result to be advanceable along a course and is further configured to allow to select a predetermined pace (A-B) of advancement so that, each time said pace (A-B) of advancement is traveled, at least one point belonging to the part of conducting material cyclically enters in contact with said course, in order to acquire the impedentiometric values relative to the segment contacted.
