Eddy currents are electrical phenomena that take place when a conductor is exposed to an oscilation of the magnetic field due to the relative motion of the field source and conductor; rewind. You have a conductor, say a copper tube, and a magnet. One moves relative to the other and you’ve got current (basically a circulating flow of electrons). These currents also generate heat as well as electromagnetism, and can be harnessed. I won’t go into additional details which you can find on wikipedia or physling, but instead, I’m gonna show you this video, which is just another example of how amazing physics really is.
Finally, an exosuit that does both.