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Box Jumps Higher Than Vertical Jumps


#1

Why are box jumps always higher than vertical jumps?
I am not sure what category this belongs but there are some knlowledgeable guys here.


#2

You mean that when you jump off a box you can jump higher than if you just jump off the ground? Or are you talking about jumping up onto a box ???...

In the case of depth jumps -

There are people on here that could explain it better than I but I will have a crack at it ... - When you jump you are using what is called the stretch-shortening cycle - essentially your muscles have the ability to "store" energy for a brief time( like a rubber band). When you jump you are using some of the stored(potential) energy (gravity) and converting it into upward force. Therefore when you jump down from a box there is more potential force and therefore a higher jump.

This is why a box jump that is NOT higher than a regular jump is seen as a sign that the athlete is poor in his "reactivity" or something along those lines( his ability to convert potential energy to kinetic energy... I think). This is very common in women, especially untrained, as they often actual have a higher standing vertical than running vertical - they can't transfer the "horizontal" energy into upwards energy. The depth jump is along the same lines.

It's important to note that this only holds for drops in a certain range. ie - jumping off of something 15 feet high is not going to mean you jump 6 feet off the ground.....


#3

Because you can bend your knees all the way to your chest in box jumps.


#4

a box jump is going to be higher than a vertical jump because you lift your feet up/bend your knees on a box jump.

a vertical jump is the difference between your highest point reached while standing vs your highest point reached while jumping. it doesnt take into account the bending of your knees.


#5

I really hope the OP didn't mean jumping up ONTO a box..... or else, well, I really don't know ...

I gave him the benefit of the doubt.


#6

Da Fuck?? The energy stored in your legs before a jump has NOTHING to do with gravitational potential energy. Gravitational potential energy will do nothing to produce an upward force, since, last I checked, it is down...towards the center of the earth.


#7

Sorry yes I did mean jumping onto a box. But thanks for the explanation of depth jumps.
I know it seems stupid but it didn't occur to me that your knees keep travelling to your chest in the box jump.
Also I think you can get more backswing i.e. forcing you hands down which you can't do in a vertical jump.

Does anyone have any norms for the typical difference in stationary box jumps compared to stationary vertical jumps?


#8

No offense, but you are making this way more complicated than it needs to be. Do this: jump as high as you can. After that, jump as high as you can but tuck your knees into your chest. Which one has your feet further off the ground? That has nothing to do with back swing or hand placement. It's common sense man.


#9

I could very well be wrong..... but -

yes, the gravitational force is "downward" but it is my understanding that your muscles can store this energy. Its the same as jumping after a run - when your running the energy is "horizontal" but you can transfer it or "redirect" it into upwards force.

If im wrong could you explain to me why a box jump (jumping OFF a box) produces a higher jump than jumping off the ground ?


#10

I imagine it like this - you have an elastic band with a weight on one end and you hold the other end. You drop the weighted end and it starts traveling towards the earth reaches a point, stops, and then rebounds and travels in the other direction. This rebound is only possible because of the initial downward force because of gravity......the elastic band has stored the downward energy.


#11

You are looking at it the wrong way. The potential energy stored is internal, just like the potential energy in our legs that enables us to jump is energy stored in our legs. It HAS NOTHING to do with how high you are. You will NOT JUMP HIGHER JUST BECAUSE YOU START ON A BOX.


#12

I've never seen anyone come close to their vert off a box, and generally the higher the box the farther the discrepancy. Tmay's thinking, just has some stuff switched around.


#13

How come MANY coaches talk of depth jump vert vs standing vert and that if your depth jump is NOT higher than you lack reactivity? I have read this many times. Are these guys crazy ? I honestly want to figure this out, not trying to argue with you....

This is from Kelly Baggett -

"If your best vertical jump from a regular standing position is better then your best depth jump from even a very low box height (~ 8 inches) then you should use landings via drop jumps to increase your ability to gather energy and optimize force absorption capabilities. If your depth jumps are higher then your regular standing vertical jump then you are a good candidate for depth jumps. "

Again from Bagget -

Those who are faster than they are strong will tend to have many of the following characteristics:

E: Your bounce depth jump (from a box height of 12-18 inches or more) will be higher than your best standing verical jump.

Again - If plyometrics are already part of your training, use a box that results in your highest vertical. For example, if you can jump 30″ from a 12″ box, 32″ from a 18″ box, but only 31″ from a 24″ box. Use an 18″ box.

Those are just a few examples. I know that I have heard Defranco talk about assessing reactivity using depth jumps in the same manner but I can't find the info.

Thoughts?


#14

Can someone post a vid please? I have no idea what the fuck anyone is talking about anymore?

Whether I jump from 10feet above ground or off the ground, I will still hit the same vertical. Does this mean you can jump higher in the mountains, because you have more gravitational potential energy up there? C'mon...


#15

Ah, I see the problem.

We are not talking about jumping off the ground at higher elevations. But jumping off something elevated onto the ground. ie - Standing on a box - stepping off the box, falling 12 - 18inches, hitting the ground and then jumping up. THIS jump is higher because you DO have more potential energy as you're elevated OFF the ground.


#16

Like this(pathetic example..)-


#17

wooooowwwwwww.........impressive


#18

LMAO! Ok. I got it now. Yea, so gravitational potential energy is being converted into internal energy within the "spring" that is your legs. Got it.


#19

Not me.... I got hops,, unlike this dude....


#20

You have less gravitational potential energy in the mountains only because gravity is slightly less.

/douche