Food for thought - How do the Pros adjust their nose angles with different starting angles, (briefcase, flat, reverse briefcase, etc.), and different reach back, power pocket and arm release angles? Is it grip, forearm pronation/supination and/or internal/external shoulder rotation?
It is very clear that GG, from a briefcase starting position, is going to have to rotate his arm, hand and disc in order to have a flat release. So I went in to my mocap software and measured the change in forearm rotation and shoulder rotation of briefcase hangers, RIcky and GG, and generally flatter throwers, Calvin and Chris Dickerson. Here is a very small sample size of unscientific data (I don't know their specific grips and I don't know their exact nose angles for the throws analyzed.). This is taking the relative positions of each joint center at max reach back (RB), deepest power pocket (PP) and release. Hard for many to understand, but I think many of us nerds on this forum may be able to grasp the following numbers. PP to release is relevant to this thread.
Ricky - From max RB to his deepest PP, 6° of supination and 17° of internal shoulder rotation. From PP to release, 10° of supination, and 23° of external shoulder rotation. Net hand rotation (forearm/shoulder) from PP to release in a nose down direction 33°.
GG - From max RB to his deepest PP, 10° of pronation and 22° of internal shoulder rotation. From PP to release, 19° of supination and 27° of external shoulder rotation. Net hand rotation (forearm/shoulder) from PP to release in a nose down direction 46°.
Calvin - From max RB to his deepest PP, 13° of supination and 28° of internal shoulder rotation. From PP to release, 3° of pronation and 15° of external shoulder rotation. Net hand rotation (forearm/shoulder) from PP to release in a nose down direction 12°.
CDick - From max RB to his deepest PP, he has 7° of supination and 33° of internal shoulder rotation. From PP to release, 16.5° of pronation, and 28° of external shoulder rotation. Net hand rotation (forearm/shoulder) from PP to release in a nose down direction 11.5°.
These world class pros have intuitively figured out a way to control their nose angles with varied body positions and timing. It appears that the primary driver is external shoulder rotation with help from forearm rotation. So when you look at wrist angles on 2D images, or are trying to understand turn the key, or pour the coffee, please realize that it is a complex learned coordination that getting there may be different for everyone. I hope to mocap some other pros later this year and I will combine with TechDisc and try to get better data.
