I looked @ some High speed clips in the archive trying to quantify some of the phenomena you've noticed Air Force.
I compared how many frames it took for each player on a first serve to go from a full extension of their left legs (an marker that the leg has completed it's contribution) to the start of internal rotation of their arms. The elbow is extending around this time as well.
It takes Agassi 3 frames whereas it takes Roddick 10 frames.
I'd guess that Roddick's flexibility allows him to stretch for a longer time before releasing that stored energy contributed by his lower body.
The next question I'd have is... Can you train this?
I compared how many frames it took for each player on a first serve to go from a full extension of their left legs (an marker that the leg has completed it's contribution) to the start of internal rotation of their arms. The elbow is extending around this time as well.
It takes Agassi 3 frames whereas it takes Roddick 10 frames.
I'd guess that Roddick's flexibility allows him to stretch for a longer time before releasing that stored energy contributed by his lower body.
The next question I'd have is... Can you train this?
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