Bioelectric

Bioelectricity, electric potentials and currents produced by or occurring within living organisms.Bioelectric potentials are generated by a variety of biological processes and generally range in strength from one to a few hundred millivolts.

Basics of Measuring Bio-Electricity

Bioelectric signals are provoked by electrically active tissue like the heart, the muscles or the brain. This active tissue can cause some concentration differences in the extra-cellular fluid that includes ions like Na+, K+, and Cl-. That is the reason that one can measure signals like ECG, EEG or EMG from outside the body on the surface of the skin, by means of electrodes.

The electrode builds an interface between the extra-cellular fluid and the metal of the wire. The electrode is a sensor consisting of a metal and often a salt-bridge, which converts the local differences of the concentration of charged ions into an electrical signal. The bioelectric signal measured from the surface of the skin is mostly in the range of 0-2000 µV (2 mV).

Electrical stimulation

Also known as neuromuscular electrical stimulation (NMES)

electrical muscle stimulation