The critical part of the box jump is that your center of mass moves the entire height of the box. This can be accomplished by stepping up or jumping up. The most efficient and dynamic way to complete the box jump is to jump up, jump down and immediately jump back up, spending as little time on the ground as possible. To improve your speed on the box jump start with a low box you can cycle them on and gradually build up in height. Make sure your hip opens completely at some point after you have landed on the box.
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Workout:
For time:
225 pound Deadlift, 21 reps
400 meter Run
225 pound Deadlift, 18 reps
400 meter Run
225 pound Deadlift, 15 reps
400 meter Run
225 pound Deadlift, 12 reps
400 meter Run
