SEATED BOX JUMP
Active or deload week, these are a phenomenal dynamic effort and a valuable spin on the standard box jump. Seated at/or just above parallel you remove the stretch reflex utilized by loading the hamstrings and hips with a standard box jump. The video below isn’t perfect, but I included it because he actually does the initial jump fairly spot on.
Chest up and head up, you rock back briefly (feet coming up a touch), only then to slam the feet down and explode up. Meant to emulate the box squat.
Keep in mind the hands are equally important. As with any good jumper or sprinter you have to utilize the hands and arms correctly. On a jump like this, start with the hands extended out in front of you, eye level. As you perform that brief rock back while bringing the feet off the ground, bring the hands down quickly breaking the angle of the hip, to then snap them up to eye level as you progress through the jump. Even though we’re alleviating that stretch reflex in the legs, we can use the stretch reflex in the upper body.
Overall, using the upper body to its full potential on a box jump, vertical jump or even a broad jump may seem like a “moo” point, but it’s actually what can make the difference between plateauing and setting a new PR.