On a good Tsukahara vault the lead arm bends in order to PUSH. The far arm is kept straight to BLOCK.
This was true when Mitsuo Tsukahara first popularized this vault in 1976.
This is true even for very young gymnasts.
Woodward West Gymnastics Camp
The stronger the vaulter, the more the lead arm can be bent with a net gain in power.
Sadly some Women’s judges are still deducting that lead arm bend as “bad form”.
No deduction if gymnast’s lead arm bends during a ¼ on or Tsukahara entry vault. Deduct for bending of second arm.
NCAA Rules Women’s Artistic Gymnastics 2009
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