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Exercises Movements, technique & proper execution

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Old 01-19-2011, 05:53 PM   #11
Lincoln Brigham
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Re: pushing from rack position in clean and jerk

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If you drop down while pushing yourself down under the bar you can accelerate down faster than with gravity alone while also slightly slowing the bar...
What I've noticed with the split jerk is that the heavier the weight, the faster my feet have to move to get into the same position.
That's assuming you haven't driven the bar up as high as with the lighter weights. Once we've driven the bar off the shoulders the thought process isn't to continue to drive the bar higher or retard its eventual descent. We're only trying to get our body down. As a physics teacher I'm sure you also realize that the heavier the bar the more force you can use to push yourself under it. Weightless mass pushing against weightless mass. Since the bar is expected to outweigh the lifter (we hope!) then the effect of lifter pushing against the bar will have more effect on the lifter's downward speed than the bar's upward trajectory.
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Old 01-19-2011, 07:43 PM   #12
Matt Haxmeier
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Re: pushing from rack position in clean and jerk

If you have a lot of time on your hands I found this article on the jerk extremely informative....

http://sportivnypress.com/documents/35.html (WFS)

Lots of good tidbits regarding pressing and how it ISN'T as applicable to jerking as one might think. It's really more about lower body strength than shoulders although speed/power are crucial for driving your body under the bar.

"The fact of the matter is that the lifter should not try to press the barbell in the jerk at all because pressing it involves lifting it with the arms and shoulders. One should use the arms and shoulders to push the trunk away from the barbell, i.e., to push the lifter into the split or half squat position (2,8,20,24,41). The kinetic energy of the descending body is transmitted to the barbell through the pressure of the hands on the bar (40,45)."

"The slow muscular contraction involved in strict pressing heavy weights is very close to isometric conditions. High muscle tonus can occur as a result of excessive or frequent use of isometrics (or what is essentially an isometric contraction when one presses or deadlifts a heavy weight). High muscle tonus is known to manifest a negative carry - over to the speed strength exercises: the snatch and the clean and jerk."

Last edited by Matt Haxmeier : 01-19-2011 at 07:48 PM.
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Old 01-19-2011, 09:29 PM   #13
Matt Haxmeier
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Re: pushing from rack position in clean and jerk

And another pretty nerdy study on the phases of the jerk...

http://w4.ub.uni-konstanz.de/cpa/art...File/2597/2448 (WFS)

"Vertical barbell displacement must be sufficient
enough to allow the lifter to fix the barbell overhead. This displacement is closely
related to the barbell velocity generated during the thrust phase."
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