If you see someone in the gym holding yourself with an "electric drill", don't worry about it. Often, their hands are the "relaxing artifact" of the popular fitness circle-the fascia gun.
We can see from various European and American sports events that many athletes use fascia guns to relax their muscles during the game. Fascia guns are used in the United States MLB, NFL, NBA, NHL professional teams, European football club teams, professional athletes in Europe and the United States, the United States Army and sports enthusiasts.