Medical Definition of Z LINE. : any of the dark bands across a striated muscle fiber that mark the junction of actin filaments in adjacent sarcomeres.Britannica.com: Encyclopedia article about Z line.efinition of Z LINE. : any of the dark thin bands across a striated muscle fiber that mark the junction of actin filaments in adjacent sarcomeres. ADVERTISEMENT.
The average fb speed in the MLB is 91-92ish. Catchers compete with this when trying to throw down a runner at 90ish. The average throw speed from third base is 80 MPH. As for the rest of the positions I am not sure of the exact average, but it is not as fast or faster than pitch speed.
I'm in a serious debate. I say Mickey Mantle was one of the fastest, if not the fastest, ballplayer of all time. Of course, there's dissent and I need facts to prove my case. I read that he was once clocked at 3.1 seconds to first base. That would put him at around 4.1 seconds for 40 yds. That's world class speed, even by today's standards.