This is a lower-body explosive, plyometric exercise.
1. Begin by standing on the floor, in front of a box that you can comfortably jump on top of. Generally, if you are accustomed to this exercise the box would be 18 inches or more in height.
2. Flexing your knees and forcing both arms upward to help propel you motion, jump on top of the box, landing with both feet – on the balls of your feet.
3. Jump back down to the starting position. You have completed one repetition and are ready for the next. Perform the required number of reps and sets for your program.