IGNORED
My favorite Peter Kostis analysis
Note: This thread is 2878 days old. We appreciate that you found this thread instead of starting a new one, but if you plan to post here please make sure it's still relevant. If not, please start a new topic. Thank you!
-
Topics Being Discussed Right Now on The Sand Trap
-
- 5 replies
- 247 views
-
- 2 replies
- 158 views
-
- 12,009 replies
- 1,124,893 views
-
"5 Minutes Daily" Practice Challenge 1 2 3 4 1064
By iacas, in Instruction and Playing Tips
- 5 minutes daily
- dedication
- (and 6 more)
- 19,136 replies
- 2,080,075 views
-
- 33 replies
- 5,615 views
-
Announcements
-
TST Partners
Coupon Codes (save 10-20%): "IACAS" for Mevo/Stack/FitForGolf, "IACASPLUS" for Mevo+/Pro Package, and "THESANDTRAP" for ShotScope. 15% off TourStriker (no code). -
Popular Now
-
-
Posts
-
No one should measure a joint mobility away from that joint. If you go to physical therapy, they are not measuring your knee mobility based on your midline. It is based at the joint. Shoulder mobility should be measured in reference to the shoulder joint. -
He's using a driver swing, while I used the iron swing. Bryson goes from about 65° B to 15° B, hence the 50°. If you bend your right elbow, you're going to pull your hands across your chest some. Conversely, if you abduct your right arm and hold onto a grip with your left arm, you can see how extending the right elbow as we do in the golf swing during the downswing will "pull" the right shoulder/humerus forward (adducting it, as going from 65° to 15° of abduction is). Even people who pull their right shoulder WAY too far around them eventually get it "back in front" when their right arm/elbow extends. So, such a motion shows up as shoulder adduction even though the movement that causes it is just widening the trail elbow. The left hand on the grip almost "pulls" the hands forward as the left arm can't stretch much (there's some shoulder protraction, but that's almost maxed out at P4). Oh, I downloaded it and watched it (and commented there) before he blocked me. It's what led to him posting the comment in the "update" above. 😄 Single shoulder range of 75°, and that's going out well into the follow-through. 50° Max range up to impact. Manavian's video is bad. He keeps saying "midline" which is just a horrible way to look at it. He also kept saying that the club was moving that amount — also wrong. Adding left and right together is really freaking dumb. Another golf instructor said "That's like saying the player has 100 degrees of knee bend (adding left knee bend to right knee bend) 🤦♂️" (similar to what the biomechanist said about squatting). Also, see my post above about elbow bend. That's why Plummer’s alignment stick demo is so intellectually dishonest. A golfer can't get anywhere near that position on the left with his left hand on the alignment stick (quoted below). -
That makes no sense at all. so, I watched that Instagram. Here is a summary... Bryson.... Address: Trail Shoulder 0 degrees adduction. P4: Trail Shoulder 65-deg abduction. Impact: Right shoulder 15-deg abduction. P9: 10 degrees adduction. Rory... Address: Trail Shoulder 16 degrees adduction. P4: Trail Shoulder 26 degrees abduction. Impact: Right shoulder 0 degrees abduction. P9: 18 degrees of adduction. DJ... Address: Trail Shoulder 4 degrees adduction. P4: Trail Shoulder 42 degrees abduction. Impact: Right shoulder 2 degrees abduction. P9: 15 degrees of adduction. Their point is that arm doesn't stay on the trail side. That the arms have to get across the chest from P4 to P9. I mean they do. What matters is the rate of which it happens relative to the position of the swing. The trail shoulder at P9 is not abducted a lot. The range of that total abduction movement is like 40 to 70 degrees. Bryson might be an outlier. Rory might be an outlier as well. A couple of points. 1. None of them had any adduction at impact. So, this tells me the trail arms stays on the trail side of the body at impact. Is it moving towards lead shoulder, yes. It doesn't happen till post impact. The right side of the body is moving towards the target, so the arms don't have to as much as people think. 2. Trail shoulder adduction from Impact to P9 is 18 to 25 degrees. 3. P9 adduction of the trail shoulder is only about 2 to 12 degrees more adducted than at address. The arms/hands stay in front of the chest a long-time post impact. If Rory, from his address position just rotated his body towards the target and raised up his arms so he is at P9. He basically didn't have to move his trail arm further across his chest than where he started at address. Visualize that for a bit. I bet for people who tend to stall and drag their arms across their body to hit the ball, that would emphasize how much the arms stay in front of the body and how much you have to turn.
-
By BrooksButlerHays · Posted
Do you know how Manavian is measuring his shoulder adduction-abduction that purports to demonstrate 50 degrees or motion in Bryson's downswing? I know the broader biomechanics research/scientific literature on this suggests shoulder adduction-abduction is only a modest contributor of force generation in the downswing, so I'm definitely not convinced by anything he's arguing, I'm just curious how different people can be claiming to use ostensibly the same "data" to tell a much different story. -
I have an update… I don't have much of a response, because the fact that they would ADD the numbers for the lead and trail shoulder together… I mean, wow. I was giving them too much credit. Nobody would think to assume they were doing THAT. That's beyond comical. One of the biomechanists I talked to put it this way: "So if I squatted down and went from 180 to 90 deg knee angle, then I would say 180 deg range of motion because I have two knees?" I'd type more (maybe), but honestly, I'm laughing a bit too hard. 🤣 Update: Mini Manavian blocked me on Instagram, so I cannot see his post showing Bryson with about 50° of range of motion (with a driver) from P4 to P7, and 75° only if you go out to the mid-follow-through. What a terrible loss for me. 😉
-
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now