Improved "active" electrodes for recording bioelectric signals in work physiology

Conventional recording techniques of bioelectric signals using surface electrodes are often very sensitive to artefacts, in particular when carrying out physiological investigations in ergonomics and sports. An "active" electrode, by means of impedance-converting-amplification, was developed to reduce motion artefacts in recording of bioelectrical signals. The application of these electrodes on the skin surface does not differ from that of conventional electrodes. The circuit elements of the impedance-converting-preamplifier, including a power-supply, are placed in a small portable housing. A qualitative comparison between conventional Ag/AgCl electrodes and "active" electrodes in ECG and EMG recordings with artefact simulation shows a high degree of artefact suppression for the "active" electrodes.