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Exercises Movements, technique & proper execution

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Old 12-18-2006, 05:53 PM   #1
Craig Uchimura
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We've been doing our box jumps from the top and jumping off then immediately go back to the top. Recently the videos posted with the WOD's show people starting at the bottom, jumping up and stepping off. Is this the preferred method? Or is it more of a beginner level?

I've done a search here but couldn't find an answer. Also remember reading that it is not necessary to come to complete extension at the top because you are extending at the bottom if doing it the plyometric way.

Any help would be greatly appreciated.
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Old 12-18-2006, 06:22 PM   #2
Lynne Pitts
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Craig,
I'll let others answer re starting point, although I've never seen or heard of it done any way but floor-box-floor. You MUST come to complete extension at the top. The only variant is, if you jump up onto the box, and then fully extend your hips on the jump off the box, you don't have to fully extend ON the box. I'll see if I can dig up a video clip of that.
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Old 12-18-2006, 09:26 PM   #3
Craig Uchimura
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Thanks Lynne,
I guess I somehow got it stuck in my head to think that the ground was like a hot stove and you want to spend as little time there as possible. Kind of like the video clip of box jumps on the exercise page.

I guess that's where I also thought you didn't need to come to a complete extension on the box as it appears that you are fully extended (although not under load) on the way down.

It would seem like such an easy task to 'jump on a box'. But I'd like to get the most benefit (punishment) possible.

Mahalo again.
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Old 12-19-2006, 08:35 AM   #4
Roger Harrell
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We do them both ways. We actually have them designated differently.
Box jumps stop at top
Box jumps stop at bottom

You don't really "stop" moving per se, but a stop at top is all about anticipating the ground and bounding off. This is for gymnastics punching drills and we do it on rebounding surfaces, not pavement,

Stop on bottom is about the jump up, power off the floor.
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Old 12-19-2006, 09:40 AM   #5
Craig Uchimura
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Thanks Roger,
Rebounding off the concrete is a little tough on the achilles.

When you say 'power off the floor' do you mean that it takes a little more 'oomph' to get up from the bottom in a static (not a complete stop but a crouch into a squat) stance rather than using the loading of the muscles from the landing portion of going top to the ground? That's how it feels to me. For days like Fight Gone Bad or Filthy Fifties it's seems easier to start at the top to keep the momentum.

I guess we'll switch to the ground up and see if we can develop more power.

Thanks for the info.

Mahalo,
Waikele Fire Station
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Old 12-19-2006, 03:12 PM   #6
Jeff Belyeu
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I certainly am no expert on this subject, but this may be (somewhat) related to a post by coach Rip I think about stopping at the bottom of Deadlifts vs a rebound type of action. Even if there isn't a bounce off the floor exactly, there is a resiliency or stretch and rebound type action in your muscles. I hope I am paraphrasing that correctly. I think this was part of the WOD posts from a couple of days ago with the 5x5 DLs. This may be a stretch of the logic, but I think there may be some correlation.

Here is part of it:

Anthony #173: Here is a little thing I'm working on now regarding the RDL vs. the deadlift, that might help:

But more important is the difference in the fundamental nature of the two movements. The deadlift starts with a concentric contraction as the bar is pulled from the floor, and the eccentric phase is not really emphasized since the lift is essentially over after it is locked out at the top. In contrast the RDL is like the squat in that the movement starts with an eccentric contraction that precedes the concentric. The bar starts from a position of knee and hip extension, the bar is lowered down into flexion and a stretch-shortening cycle or stretch reflex, initiates the concentric contraction back into extension.
Any concentric contraction is stronger when it is preceded by a stretch reflex, due to increased efficiency in motor unit recruitment as well as the ability of the elastic components of the muscles and connective tissues to store elastic energy developed during the eccentric phase. A jump is the best example of this; every time a jump of any kind is performed, it is preceded by a short drop of the hips and knees that creates a stretch reflex. It takes a great effort of will to jump without this drop – it is such a normal part of human movement that it is very difficult to exclude, difficult to the extent that most novice lifters “cheat” their deadlifts, cleans, and other pulls from the floor by attempting to do this right before pulling. This “bounce” out of the bottom of the RDL enables rather heavy weights to be used in the exercise despite the fact that the quads have been excluded from helping with the movement. (It also explains why bouncing the second through fifth reps of a set of five deadlifts off the floor is so popular.) RDLs take advantage of the stretch reflex just to the extent that it affects the hip extensors. The fact that the quads are excluded makes the movement quite a bit different from the deadlift or any partial version of it or any other pull, so it really is a separate exercise.


Comment #176 - Posted by Rippetoe at December 16, 2006 04:47 PM
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