Originally Posted by liolio
TI looking at Terry when he swam did not but I guess some leel is ok for a healthy person wth otherwise healthy posture, etc. more and more our daily life promote position where the elbow pops out, the forearm is under pronated (max pronation is not reachable by many people), rounded shoulders; etc
=> many issues shoulder impingement but also thoracic syndroms (from the scalene to the pectoralis minor to various wrist nerves and vascular issues).
It is tempting to engage the big powerful muscles that rotates the humerus and moves the arm closer to the front of the torso when nowadays weaker back muscles is the basic (I got told by a teacher that it is safe to assume that most people lower trapezius are way to weak).
It is quite complicate but if you don't rely on internal rotation you have to move you scapula around and it is a pretty solid articulation (no real joint /serratus). As the scapula moves and you extend your arm and fore arm you hae to use the long head triceps more extensively (you keep you elbow closer to your body). It is significantly different kinetic chain, you have to feel it for your self I'm not sure if trained properly it is less efficient actually I would think Phelps does that (though he engage internal rotator for extra juice or not pull too deep).
I stepped slowly through your description, and from what I understand, you are saying that you can get the similar effect of arm pronation (internal rotation of the humerus on the glenoid fossa, i.e. the "joint" of the scapula) by rotating the whole scapula and sliding it up the posterior rib cage as you reach your mail-slot spearing arm along the line of the swimming direction, thus avoiding potential shoulder rotation repetitive strain injury.
This is a whole new idea for me, and I have never heard of it before. As you say, it involves a whole new kinetic chain. I would have no idea where and how to start training for this motion. Is there any existing literature out there that you know of that deals with this?