Dartfish Technique Analysis - July 2014

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CJ Cummings' Clean & Jerk Technique

I took these clips at the recent USAW Youth National Championships. CJ Cummings displays very consistent technique in his three platform clean and jerk attempts. Trajectories are marked, along with lines indicating the recommended step forward distance during the split.

Note that Cummings does not move his front foot as far forward as is recommended. This failure to step out about 1.5 times the length of his shoe results in a greater amount of weight on his front leg while in the split. This causes no problems on his first and second attempts, where he is able to recover from the split as is normally recommended. But by his third attempt this failure to step through leads to his recovering forward.

Forward recoveries always result in horizontal movement of the bar. Although all three jerks are received at arms' length overhead, his record attempt at 153kg "gets away" from him and is lost due to this combination of small errors.

The lifts play in both regular and slow motion speeds. Utilize Dartfish's Next Frame option to watch the lifts frame-by-frame.


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