Shell defense is where you have four defensive players and four offensive players. 4 on 4 on 4 is a defensive/offensive drill to help on backside defense.
You have have three teams of four. one team starts up the floor and the defense gets into shell ‘D’. And the offense must pass the ball three times, after the three times you are live four on four. If the offense gets the rebound the defense must run a line drill, and the offense goes to the other end of the of the court and does the same.
offense/defense
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TLC: Pål Degerstrøm 2000-2008