Aim: Develop explosive power from the deck and defensive leg drive.
One player holding a contact shield across his chest performs four up and downs onto the deck on the four points of an imaginary cross as quickly as possible. As he gets up after the fourth one he braces himself and his partner, who is standing waiting for him hits into him and drives him backwards.
Emphasize speed onto and off the ground. Ensure correct body position with the drive. Straight back, good shoulder, not arm, contact, and bent legs.