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.
Major League Scouts consider 90 mph an average major league fast ball. 95 mph is considered a plus fastball velocity, and +97-98 mph a plus, plus velocity. the 90 range is a good speed for an mlb pitcher. some pitchers do pitch in the high 80s though.real good pitchers pitch 100mph too. Randy Johnson threw a 103 mph fastball.5 mph is considered a plus fastball velocity, and +97-98 mph a plus, plus velocity. the 90 range is a good speed for an mlb pitcher. some pitchers do pitch in the high 80s though.