The box used for this drill should be small to promote quick repetitive hops. Drive laterally with the inside foot (foot on top of the box) to clear the box and land on the other side with the opposite foot now on the floor. Land softly as possible on the box and floor, and drive back with the inside foot (foot on top of the box) to the starting position as quickly as possible. The idea is to have minimal contact time with the ground, and perform many reps in a short period of time. FOR INSTRUCTIONAL PURPOSES EXERCISE IS PERFORMED AT SUB-MAXIMAL SPEED!