The purpose of this "rolled ball" drill from Rice University's Genny Volpe is to warm up your players and get their feet moving on defense.
How it works: a coach at the net rolls balls towards a defending player in middle back. The player needs to hustle to roll back (or just touch) 10 balls in order to complete the drill.
A variation you could use to get additional players involved could have two or more players doing pushups (or another exercise) outside the court until the player on court reaches 10 touches.
