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Post by imperfectgolfer on Dec 9, 2010 1:47:09 GMT -5
At the BM Anti-Summit, Mike Finney asked Rob Neal whether the shoulders always have to turn around the upper thoracic spine at 90 degrees. Rob Neal said yes, and that answer seemingly satisfied Mike Finney. The reality is that it is possible to vary the shoulder turn angle relative to the upper thoracic spine. The sterno-manubrial joint (where the clavicles attach to the sternum) is a movable joint and one can vary the angle between the clavicles and the sternum. That happens when one shrugs one shoulders. Consider this posed Ben Hogan photo. Note that the shoulders are not perfectly at right angles to the upper thoracic spine in image 2 - the right shoulder is being depressed downwards, while the left shoulder is being elevated upwards. Here are the four possible independent shoulder movements - depression, elevation, retraction and protraction. Jeff.
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Post by ringer on Dec 9, 2010 11:56:05 GMT -5
In none of those images do I see a woman "turning" her shoulders.
I am quite sure that someone can lift their shoulder up or back as in a shrug, but when they rotate, it's 90 degrees. You could independently shrug a shoulder AND rotate which would give the appearance of it not turning at right angle to the spine, but ultimately the rotation of it is still 90 degrees.
I am not opposed to someone saying it doesn't always have to move 90 degree's because they could be doing both movements simultaneously thereby moving the shoulder joint in a non-right angle manner. But I don't think either way is wrong.
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Post by imperfectgolfer on Dec 9, 2010 11:57:53 GMT -5
See this 3 jack thread. richie3jack.proboards.com/index.cgi?board=general&action=display&thread=1488Dan wrote-: "Rohlio, perhaps he's talking about the pure rotational movement. Shrug one shoulder up, now turn. It's still going to turn in a "circle" and the center of that circle is still the spine... just that the two shoulders won't be tracing the same circle. If that's the way he's thinking, then fine, but I'm not sure that's in the spirit of the question or what Richie was after when he asked." Ringer then replied-: "I think that's precisely the distinction that should be made more. They rotate 90 degrees to the top of the spine, but not necessarily on the same plane." If the right shoulder is being depressed during its rotational movement in the early downswing, then it must be continuously changing planes (relative to the spine) while the upper torso rotates. Therefore, I cannot understand how it can be perceived to be rotating at exactly 90 degrees relative to the spine - unless the rate of depression of the right shoulder per unit time was perfectly time-coordinated with the rate of torso rotation per unit time. I don't think that happens in many golfers who depress their right shoulder during the club slotting phase of the downswing. Jeff.
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Post by imperfectgolfer on Dec 9, 2010 12:04:23 GMT -5
Ringer,
You wrote-: "In none of those images do I see a woman "turning" her shoulders.
I am quite sure that someone can lift their shoulder up or back as in a shrug, but when they rotate, it's 90 degrees. You could independently shrug a shoulder AND rotate which would give the appearance of it not turning at right angle to the spine, but ultimately the rotation of it is still 90 degrees."
In a golf swing, I don't think that one turns (rotates) the shoulders. I think that one rotates the upper torso around the spine, and this usually occurs at a ~90 degree angle. However, during that upper torso rotation process, the shoulders can move independently of the upper torso eg. right shoulder can be depressed and/or protracted. If the rate of independent shoulder motion occurs at a different rate than the rate of upper torso rotation around the spine, then I cannot understand why the shoulder arc path will always be at a 90 degree angle relative to the spine.
Jeff.
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Post by ringer on Dec 9, 2010 12:27:43 GMT -5
Ringer, You wrote-: "In none of those images do I see a woman "turning" her shoulders. I am quite sure that someone can lift their shoulder up or back as in a shrug, but when they rotate, it's 90 degrees. You could independently shrug a shoulder AND rotate which would give the appearance of it not turning at right angle to the spine, but ultimately the rotation of it is still 90 degrees." In a golf swing, I don't think that one turns (rotates) the shoulders. I think that one rotates the upper torso around the spine, and this usually occurs at a ~90 degree angle. However, during that upper torso rotation process, the shoulders can move independently of the upper torso eg. right shoulder can be depressed and/or protracted. If the rate of independent shoulder motion occurs at a different rate than the rate of upper torso rotation around the spine, then I cannot understand why the shoulder arc path will always be at a 90 degree angle relative to the spine. Jeff. I think everyone is pretty much in agreement with this. What is "optimal" is of course up for debate.
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