A site must be build for explain all the defense system. This is only few examples.
Defense -Diving & Rolling :
Players made a line.. The coach at 9 meters of the players make a forearm set in a zone situated at 6 meters of the players. The diggers must shares to go up the goal to the setter area.
Defense-Dig :
The coach forward the net served on the « 3 meters area ». Diggers (on position 6) must dig the ball.
Better Defense :
The coach stand up on a bench forward the net have all the balls. Diggers make a lap on going touch the target and dig the ball spiked by the coach.