The paper presents the results of experiments of the relationship between the change in electrical impedance and the force of brush compression determination. Within the framework of the research, an isometric compression stand was developed, which allows recording the brush compression parameters. On the developed stand, experiments were carried out, during which the simultaneous registration of the impedance signal from the muscles of the forearm and the compression force of the stand was carried out. The relationship between the impedance change and the action force was determined. The use of this dependence in the development of bio-controlled devices will allow to control it more accurately.