- Start with both feet on the ground in front of the box.
- Jump on top of the box attaining full extension at the top (lock out your knees).
- Jump or step back down and repeat.
- Note: You may attain full extension of your body in the air after jumping off of the box as long as it is attained while your body is still over top of the box and not behind the box.
And here’s Dr. Paul at age 55 doing ‘rock jumps’: