Dr. Kwon’s DG 3D motion study

[Brychanus]

Can you break down how the hips are involved in translating momentum and ground force up through the body in disc golf, please? I mean could you use Wiggins' form as an example of how it's done right? 'cause I'm still trying to wrap my head around the specifics...

TL;DR: Exactly the same way as in ball golf, but swinging your arm and leveraging out the disc with one arm on a parabolic line rather than the club with two arms hitting the ball on a parabolic line.

Still TL; DR: Just do it.

Not Long Enough, Tell Me More:
You should watch The Hips golf videos SW linked closely and probably more than once. Visual memory helps you understand how to the hips move and why separating them arbitrarily from everything else is a mistake. Babies do this before they got all their adult-like schemas and anxieties and attention to verbal details and it helps them learn to move. It's good to be a baby when learning a new motor skill. For some reason people seem to have particular difficulty talking about the hips or even understanding what they are physically - maybe because they never had to think about learning to walk unless they are an adult going through rehabilitation.

Once you see the hips in motion and how fluid that action really should be, you need to see the fall in ball golf (and baseball, and tennis, etc). Start with it here, which is basically the smallest "shift from behind" you can muster. Clement is falling into the plant.
https://youtu.be/0CSHqnYNijw?t=145

Don't believe it matters or is there? Try a golf swing with and without that mechanism.

Then watch that entire video, and any of his other videos. He may not be your style, but he's a gifted instructor IMHO. His work is also basically the mechanics for a narrow-stance standstill in DG.

Once you understand that little fall, you just need to know that this is most of the DG swing (really, I'm not ****ting you):

How does that relate to the hips and momentum and ground force? He hops to fall onto the can. Gravity gives him momentum. That's what Clement is doing. Then, do you see how SW/seabas kinda compresses when he lands and his butt sticks out? That's part of the "ground force reaction" - generating a lot of weight when you land that powers the swing (gravity acting on mass and landing). Don't force it - that's just his leg resisting the ground when he lands in good posture. He's feeling that compression & leverage against the ground lead into his plant hip, and *zing* - now the shoulder and arm can come through (after being coiled into the rear side through his core). This little hop drill was one of the biggest "AHAs" I've had.

Why is this so much harder in DG? Well, it's in part because everyone just wants to X-step because they think it looks cool and doesn't realize all the other things that need to work well first. They get all twisted up and confused and lost (me too). And there are IMO still a couple things that make DG harder. The Door frame drills teach you to do this same thing - connecting the hips and the fall and everything else - but now shifting your weight together over a bigger vertical and horizontal shift and with a bit of diagonal than ball golf. You're really cooking from there if you get those ideas in your swing.

Conclusion:
Most people getting to throwing 300' have done it without learning to get this fluid posture and hip action connected to the fall and ground force reaction. Then usually soon after that they get trapped.*

This is one of the best posts here IMO tying these concepts together:
https://www.dgcoursereview.com/forums/showpost.php?p=3361690&postcount=6



Practical takeaways:
1. In high level players in DG and other sports, these mechanics are usually apparently much smaller when they're well-learned because the player has become so efficient. Know that, and use exaggerations to learn them the first time. These are some of the ideas that I usually find missing in instructional content and why I'm glad I came here.

2. Learn to fall and resist the ground as part of the shift. Narrow, wide, diagonal, and with feet moving.

3. I keep saying it recently because I think seabas/SW was well ahead of his time talking about horizontal and vertical forces. I think most players are doing themselves a disservice not working with the vertical, and not just because my body type prefers it.



Wisdom:
Sorry to be so self-referential, but I know my journey better than anyone's.

*I had a chat with a friend during a Sunday round. He knows I'm obsessed with mechanics, and we talked about the saturated YouTube space and I asked whether I should revise or redo my content, or if it even mattered. His response was interesting because he thinks mechanics-focused work might not be for everyone, and I might benefit from developing more (competitive play, challenging my swing to improve in different courses, etc.). But the most interesting thing to me was that we both agreed that learning "The Good Throw" - if that's what I'm learning here - is much harder to learn (not just because of DGCR), and it takes a major commitment compared to the exotic weaker swings out there. He can throw 330' with a Destroyer. He's not that bad at it anymore. That might be good enough for him. Sunk cost fallacy or not, it's not good enough for me. There is deep wisdom in knowing what you're getting yourself into and whether it's worth it to you.

My swing still needs work. But learning at DGCR, my body looks more like this. It didn't before. I'm not forcing it. It's on the right track. It was not before I embraced this journey. YMMV.

I hope something in there was helpful. Now you gotta go do it.

 

[Brychanus]

Cross linking to this post I just put in The Hips since it finally convinced me about how to think about learning the "ideal" action through the hips for a given body, regardless of whether you're a vertical or horizontal player. It does not contain all the answers but is relevant. As more wireframes show up I'll be curious to see more.

https://www.dgcoursereview.com/forums/showpost.php?p=3883071&postcount=79

 

[blayed]

re: That big Chris Taylor post ... I think Chris Taylor also, for better or for worse, has a big "pulling" model of the throw. Here is his response on one of Jaani's videos:

https://imgur.com/a/yagQF7x
(I know brychanus hates the use of active but I think we can understand what he means given the context of all the other stuff he has said recently)

I think it goes without saying that there's a spectrum of throwers. Is Dave Feldberg "pulling"? probably not, seems like a swing to me. But very few people throw like feldberg. I think Ezra and Eagle have clear "pulling" components to their throws, does that mean they lack any "Swing" mechanics? Probably not. Here's a video I took of eagle from behind:



I think there's a little bit of both in there.

 

[Brychanus]

re: That big Chris Taylor post ... I think Chris Taylor also, for better or for worse, has a big "pulling" model of the throw. Here is his response on one of Jaani's videos:

https://imgur.com/a/yagQF7x
(I know brychanus hates the use of active but I think we can understand what he means given the context of all the other stuff he has said recently)

I think it goes without saying that there's a spectrum of throwers. Is Dave Feldberg "pulling"? probably not, seems like a swing to me. But very few people throw like feldberg. I think Ezra and Eagle have clear "pulling" components to their throws, does that mean they lack any "Swing" mechanics? Probably not. Here's a video I took of eagle from behind:



I think there's a little bit of both in there.

I do think there are probably interesting differences in general for the moves past the disc vs. more swing or pendulum-style wind up in general. SW has written about that too from time to time. I have a couple not entirely speculative things on my mind there.

In the pendulum style (SW, Feldy, Philo, McBeth at times, younger Simon), to me, the arm is functioning like it's reacting to the tension formed in the backswing before being committed to the swing. The more "leave behind"/walk past folks like Wiggins or Eagle etc. have a little more going on with the arm motion and how the redirection works. I think their style is a little more sensitive to the integrity of what's happening on the rear side in transition (from my own experience). I suspect they're both tapping the same chain in terms of what the musculature does in sequence once they get loaded up. I personally have had an easier time accessing that with the pendulum (and now modified to a windmill) but I think that's just as much about how my body is shaped and moves for momentum and the path my own form development took as anything else.

Since the pull vs. swing abstraction is being talked about, I do think blayed is onto something that some forms may be more emphasizing a swing of the arm from the shoulder even if it's recruiting a lot or even all of the same sequence in the muscular sense. Some forms might be a little more emphasizing the pull - I think they're all still finding a way of shifting "past the door frame" and committing that chain that was pulled taut into throwing force once they land. As long as you're doing that and not collapsing posture and wasting the force you can make progress.

For instance, I've suspected for a little while that even though Eagle and Simon both have pretty horizontal forms now, Eagle has always looked to me like he has more effort earlier in his chain than Simon tends to. Eagle has always looked a little more like he is exaggerating a forceful shift and pull directly against the "door frame." Simon has that too, but it always looked like he has slightly more of a freeflowing "swing" of his arm from the shoulder. Simon's max effort 360 still looks a little more like a "swing" than Eagle's max "pull" to me. Is this true? Is one better or worse? For what? These questions remain open to me. Simon also had that pendulum action when he was younger so I've always wondered if that was part of what makes him and Eagle look so different to me. I still notice a kinetic difference in how they move in very short shots. It's subtle, but I think it might be there.



I find this easier to see a few years ago when Eagle's form was a little less smooth. I see more emphasis on "pull" potentially here than Simon ever really looked like to me:



(edit: direct link since the embedded might have a blocker there)
https://www.youtube.com/watch?v=fbn0QqWp0dE&ab_channel=TimoKoskinen

Simon of course hurt his elbow permanently, and I still wonder how much was just throwing at or near max effort too often vs. some of his mechanics or both. I kind of have a feeling that Eagle's style might wear on him more once he gets into his 30s, where if Simon keeps his impulses to juice it at bay he might keep chugging along for a while. On the other hand, maybe Eagle's is just fine and that's what his body likes to do. I personally just have gone after the smooth/parametric acceleration route however I get it since it's always easier on my body. I can also personally tell you that I can definitely find more "pull" power when I want it. I just try to integrate it into a swing to ride momentum as long as I can for efficiency. That's maybe easier to work with once parts of the swing are sufficiently developed to mold.

(I know brychanus hates the use of active but I think we can understand what he means given the context of all the other stuff he has said recently)

Totally, I'm always keen to rush to the "context" middle ground. I'm rightly called out for being a bit of a stick in the mud about the active/passive language. In an effort to get unstuck, I think that's just another case of my own verbal preference. In terms of how the action works, it was always easier for me personally to think about and build up the action more like the Clement video here. I think however you get there and whatever you call it, you want to get that flow of load and unload in sequence and good posture.

 

[timothy42b]

Since the pull vs. swing abstraction is being talked about, I do think blayed is onto something that some forms may be more emphasizing a swing of the arm from the shoulder even if it's recruiting a lot or even all of the same sequence in the muscular sense. Some forms might be a little more emphasizing the pull - I think they're all still finding a way of shifting "past the door frame" and committing that chain that was pulled taut into throwing force once they land. As long as you're doing that and not collapsing posture and wasting the force you can make progress.

There was an old study done by physicists at one of the London universities decades back that thought there were two different ball golf patterns to the swing. I've looked for it but not been able to find it again.

More recently there is Homer Kelley's The Golfing Machine, 1969. He believed you were either a hitter or a swinger. He uses some different terms also, like rope handle vs ax handle. I can't really recommend the book to most people; it is dense with his ideosyncratic terminology and hard to follow. However, the reason I bring it up is that he catalogued variations of the different elements of the swing, and came to the conclusion that while they all worked, some were incompatible with one or the other of the main swing types.

 

[sidewinder22]

I think Chris T is using a lot of the data from Sarah Hummel's thesis on the Frisbee Flight Simulation and Throw Biomechanics. This found that 50%+ of the power comes from the horizontal abduction of the humerus which Chris often states. The top velocity from this study was only 50mph and average was 26mph and throwing an Ultimate Frisbee, not golf discs.

4.5 Discussion

The data presented were based on the analysis of one thrower. It is unknown whether the results are representative of a larger group of Frisbee throwers.

67

Frisbee throws partially demonstrate the kinetic chain principle which states that peak angular velocities occur in a sequence from proximal to distal segments to generate maximum velocity at the end point (Krieghbaum and Barthels, 1996; Putnam, 1993). Peak torso twist rate occurs at –0.06 seconds followed by peak horizontal abduction, elbow and wrist extension rates at –0.04, 0.03 and 0.04 seconds respectively. In a kinetic chain, during acceleration of the proximal segment the adjacent distal segment lags behind. This is observed with the upper arm and forearm (Fig. 4-3). When the humerus begins horizontal abduction, elbow flexion begins to increase. However, in a kinetic chain all segments are contributing positive power, this is not the case with the Frisbee throw. Positive power is generated mainly by horizontal abduction and slightly by wrist flexion. However the power contribution from elbow flexion is negative throughout the throw, reaching a peak of -137 W after release. The negative power acts to decelerate the forearm, preventing a whip-like effect that may be observed in a kinetic chain.

Beginning throwers are often instructed to focus on increasing their wrist snap, but analysis of the Frisbee throw suggests otherwise. At release the power and work done at the wrist are only 8 W and 0.2 J respectively while the main components of power and work occur at the shoulder from horizontal abduction. The work done at release by horizontal abduction is 35 J while the total work of the joints is 34 J. This implies that novice throwers might experience larger improvements by instead concentrating on increasing the power at the shoulder by increasing the horizontal abduction rate. This increase in torque and angular velocity may translate, through the kinetic chain, to the wrist. While wrist snap, may be important for imparting maximum angular velocity to the Frisbee, it is possibly of secondary importance to Frisbee translational velocity for the beginning thrower.

68


The configuration of the thrower at release may be dependent on subconscious factors. At release the torso x axis, xT, is rotated 42° clockwise past the direction of the throw. The xT and xH axes are offset by only 3°, the elbow is flexed 57° and the wrist is 5° past full extension (Fig. 4-2). During the follow through, elbow extension reaches a maximum but still comes no closer than 27° to full extension. Non-full extension of the elbow during the throw suggests a subconscious reflex may be present. The configuration at release allows the thrower to somewhat face the throw direction, but does not allow maximum range of motion of horizontal abduction and elbow extension. Releasing the Frisbee when the elbow is closer to full extension might be more conducive to generating higher Frisbee velocity, however this configuration also would increase the risk of hyperextension and injury to the elbow. Subconscious protection mechanisms seem to inhibit full extension. This has been observed in other throwing events including baseball. Feltner and DePena (1986) found that at maximum extension the elbow is still 20° from full extension.

While the standard deviations are consistently narrow at release for all angles (Fig. 4-3), they vary widely throughout the throw. For example, torso twist standard deviation is as large as 25° 0.25 seconds before release but decreases to only 7° by release. This suggests that for 57% maximal effort throws, the torso twist range of motion may not heavily influence conditions at release. The small standard deviation at release for all DOFs, however, implies there may be a preferred configuration by the thrower, even at submaximal effort.

69


The kinematics and kinetics of the segments of the upper appendage have been presented. Frisbee throws result in nearly 140° horizontal abduction, 100° of which occurs before release. The elbow does not fully extend at any time during the throw. The negative power generated serves to decelerate the forearm and hand due to a possible subconscious reflex to prevent hyperextension. The positive power for the throw is primarily generated by horizontal abduction. Positive power can be maximized by facing perpendicular to the throw direction to allow for maximum range and angular velocity of horizontal abduction prior to release.

 

[drk_evns]

...so how do you throw faster than the people in the study...

lol

 

[Sard0nyx]

...so how do you throw faster than the people in the study...

lol

I don't think we should automatically discount the stuff he's teaching just because it might be based on old research....

I've had limited interaction with him, so I don't know what he's teaching, but it seems that he coaches many MPO players including David Wiggins Jr. So clearly he teaches people that throw farther than that study.

Disc golf teaching shouldn't always be about who's right and who's wrong. Cause sometimes you don't know what's right and wrong and other times, you find out they're really saying the same thing in a different way. Why can't we all focus on throwing far and talking about mechanics instead of critiquing different "methods". It's starting to feel like a witch hunt of any teachers that hop onto the scene.

 

[drk_evns]

I don't think we should automatically discount the stuff he's teaching just because it might be based on old research....

I've had limited interaction with him, so I don't know what he's teaching, but it seems that he coaches many MPO players including David Wiggins Jr. So clearly he teaches people that throw farther than that study.

Disc golf teaching shouldn't always be about who's right and who's wrong. Cause sometimes you don't know what's right and wrong and other times, you find out they're really saying the same thing in a different way. Why can't we all focus on throwing far and talking about mechanics instead of critiquing different "methods". It's starting to feel like a witch hunt of any teachers that hop onto the scene.

I actually enjoy his content a lot and have had a few short chats with him. I don't even know what/how he teaches—just responding to the study. I was being a bit tongue in cheek, but I think it's a fair question if anyone is basing their "method" on that particular study—though I doubt it's that simple.

To be fair, I'm skeptical of most "coaches" in disc golf these days and share my own opinions online much less than I used to. People are much less receptive to information unless they've specifically asked for it. Whenever I start typing out something I think might be worth sharing, I delete it and go do field work instead.

If you really want to effectively help someone, doing it in person is the way.

 

[Brychanus]

^Only thing to add there is that I believe in the role of humility and differences in emphasis & detail and the parable of the blind man and the elephant.

I'm often writing things here to help process information for myself and in the hopes someone else likes nerding out about this stuff or it inspires something positive in their journey.

I actually enjoy his content a lot and have had a few short chats with him. I don't even know what/how he teaches—just responding to the study. I was being a bit tongue in cheek, but I think it's a fair question if anyone is basing their "method" on that particular study—though I doubt it's that simple.

To be fair, I'm skeptical of most "coaches" in disc golf these days and share my own opinions online much less than I used to. People are much less receptive to information unless they've specifically asked for it. Whenever I start typing out something I think might be worth sharing, I delete it and go do field work instead.

If you really want to effectively help someone, doing it in person is the way.

I'd be sincerely curious what you often feel like saying and then deletes.

Only I'd want to say about your point about helping there is that I have worked mostly online with SW and a few others here, and it has made tremendous improvements in my swing. I do also think I would have picked up many things faster in person with him or another good coach as I do often with more experienced players in casual settings. I'm very happy with where it has taken me so far even though it might have been faster otherwise (public thanks again to SW for the lion's share of direct work & the many who have been helping me along, including drk_evns).

 

[Sewer bill]

Interesting point in sidewinders post about the study. The subconscious avoidance of hyper extending the elbow.

This is personally one of my key goals when throwing. At my peak of performance, over 10 years ago, I could push that limit of my swing to where I'd need to be fully warmed up and stretched out to put more than 75% into a distance throw or I would hyper extend my elbow. Coming back to disc throwing after nearly a decade I have much more strength right off the bat but I have had to work very hard to regain the flexibility necessary to throw that type of shot.

There's a double edge to the sword of form emulation and trying to convert visual information into your own swing. Some people are much more flexible than others and simultaneously, our vastly different lever lengths lend to needing a much more personalized approach to developing our own swing. If you could carbon copy someone else's form you could break your body just by having different lever lengths alone.

That's why I really like the multi step drills approach being taught here instead of some I have seen online trying to mimic the entire swing of some random pro who throws well. I'd bet money many people new to disc golf have actually hurt themselves by watching Simon eagle gg or any of the other big throwers and trying to emulate what they're doing.

 

[timothy42b]

Interesting point in sidewinders post about the study. The subconscious avoidance of hyper extending the elbow.

Yes, I caught that and thought it was unusually perceptive for a mechanical engineering student, even a grad student, to consider that possibility. I have a slightly different suspicion that might be involved.

I downloaded her thesis and read it last night. It's 2003 and technology has improved so much she could do it more easily and accurately today, and possibly Ultimate skills have changed as well. As mentioned, they are using an ultimate 175 g disc, and an "experienced" right handed male player. (too bad it wasn't Brodie) And it seems throws were in the range of 30 to 50 mph, though the ones in the table were not max throws.

I don't know much about ultimate, but obviously they have to throw accurately on the run from awkward positions while being guarded by opposing players, so this may not reflect the max throw as much as what is possible without the extras.

Here's what surprised me about her graphs. The thrower starts with arm in line with shoulders, adduction 0 degrees, and shoulder line pointing 20 degrees right of target. (no mention of hips) On backswing the torso rotates left to point 6 degrees right of target while the arm "flaps" through 100 degrees, basically pointing 90 degrees left of target. Don't confuse horizontal adduction with adduction - the arm is not straight out but has lowered. At the hit the arm is again in line with the shoulders, and the shoulders are turned away from target to the right about 45 degrees.

So, two conclusions, very tentative, from first reading of the thesis:
1. That's not a drive, that's a putt.
2. It's possible to get 50 mph without drive mechanics.

 

[Sewer bill]

Yes, I caught that and thought it was unusually perceptive for a mechanical engineering student, even a grad student, to consider that possibility. I have a slightly different suspicion that might be involved.

I downloaded her thesis and read it last night. It's 2003 and technology has improved so much she could do it more easily and accurately today, and possibly Ultimate skills have changed as well. As mentioned, they are using an ultimate 175 g disc, and an "experienced" right handed male player. (too bad it wasn't Brodie) And it seems throws were in the range of 30 to 50 mph, though the ones in the table were not max throws.

I don't know much about ultimate, but obviously they have to throw accurately on the run from awkward positions while being guarded by opposing players, so this may not reflect the max throw as much as what is possible without the extras.

Here's what surprised me about her graphs. The thrower starts with arm in line with shoulders, adduction 0 degrees, and shoulder line pointing 20 degrees right of target. (no mention of hips) On backswing the torso rotates left to point 6 degrees right of target while the arm "flaps" through 100 degrees, basically pointing 90 degrees left of target. Don't confuse horizontal adduction with adduction - the arm is not straight out but has lowered. At the hit the arm is again in line with the shoulders, and the shoulders are turned away from target to the right about 45 degrees.

So, two conclusions, very tentative, from first reading of the thesis:
1. That's not a drive, that's a putt.
2. It's possible to get 50 mph without drive mechanics.

I think your conclusions are sound and the angles are iffy to interpret just because of the larger disc diameter.

Distractingly, on the topic of bigger discs and form.

Throwing big discs is one of my theories of how to teach adults to throw like kids. You ever watch a little kid throw a disc and it's nearly intuitively perfect form? Sure most of them are way nose up but the swing is anatomically spot on. That's because the disc is comparatively like throwing a weighted trash can lid as an adult. The larger diameter and proportionally bigger mass to a child's body size forces the window of leverage obtained in the swing to shrink to a nearly go no go situation where bad form actually feels bad and good form clearly results in a further flight.

 

[drk_evns]

I'd be sincerely curious what you often feel like saying and then deletes.

Only I'd want to say about your point about helping there is that I have worked mostly online with SW and a few others here, and it has made tremendous improvements in my swing. I do also think I would have picked up many things faster in person with him or another good coach as I do often with more experienced players in casual settings. I'm very happy with where it has taken me so far even though it might have been faster otherwise (public thanks again to SW for the lion's share of direct work & the many who have been helping me along, including drk_evns).

I've learned most of what I know from reading and watching content online. The struggle is figuring out for yourself what works and what doesn't. What took me ~5 years to learn and understand on my own would be easily coached in days or months. It's a really fun hobby to improve and share your process/thoughts with like-minded individuals—however, if your goal is to become the best disc golfer you can be as quickly as possible—there are better avenues.

 

[Brychanus]

Oh - while we're mentioning pulls and swings (I'm gonna go ahead and call it a "swull" for now. "Throw" is also fine) and humerus abduction, the leverage and role of that humerus abduction are related to the role of the big lat muscles. This hotlink to a section on the lats in another thread made me think about it.

I think whether you prefer to think swing or pull, you can appreciate it anatomically. As usual, an anecdote:

What I lack in lower body strength I make up for in chest and lat muscles (I used to be able to bench more than I could squat or deadlift. That's not good and I'm not proud of it - don't be like me. Also, I'm having more fun and improving more with functional exercises - highly recommended!).

Once I got a lot of the upper body swing force moving reliably through the meat of my lat muscle group with better side bend, it was a clear increase in "effortless" power, and also clearly part of what makes my far shots go farther. I think the many people struggling with things like side bend lack access to this part of the chain. Wiggins and the big guns have it. Some people throwing pretty far but still leaving a bit on the table report that they get their muscle load up higher toward their traps and rhomboids and I worry that they're actually missing the muscle power that is generally higher going through the lats even if you don't spend a lot of time developing that muscle group. It's a big one in any case. Look at all this meat!

This also made me think of course about optimizing form to the person: on the one hand, you'd prefer to have the lower body better developed for your swing. On the other hand, you work with what you've got. I think that's another reason why my body has some of the form preferences it has - getting in postures that clearly support a strong lat contraction in the chain are always way more powerful than those that don't or are less optimal for me. If I get my most powerful muscle groups aligned better, I really feel that ripple of power behind the swing and my lats are doing something important - still low perceived effort, but loose, coordinated, and strong.

Maybe other people really do get a smaller percentage of their power form their lats when they're less dominant in their body, but I think it's likely to be necessary for a powerful chain in any body type due to the simple mass of that muscle group and it's role in the body's "slings" for throwing.

Just another unpatented rumination.

 

[BruisedOoze]

Yes, I caught that and thought it was unusually perceptive for a mechanical engineering student, even a grad student, to consider that possibility. I have a slightly different suspicion that might be involved.

I downloaded her thesis and read it last night. It's 2003 and technology has improved so much she could do it more easily and accurately today, and possibly Ultimate skills have changed as well. As mentioned, they are using an ultimate 175 g disc, and an "experienced" right handed male player. (too bad it wasn't Brodie) And it seems throws were in the range of 30 to 50 mph, though the ones in the table were not max throws.

I don't know much about ultimate, but obviously they have to throw accurately on the run from awkward positions while being guarded by opposing players, so this may not reflect the max throw as much as what is possible without the extras.

Here's what surprised me about her graphs. The thrower starts with arm in line with shoulders, adduction 0 degrees, and shoulder line pointing 20 degrees right of target. (no mention of hips) On backswing the torso rotates left to point 6 degrees right of target while the arm "flaps" through 100 degrees, basically pointing 90 degrees left of target. Don't confuse horizontal adduction with adduction - the arm is not straight out but has lowered. At the hit the arm is again in line with the shoulders, and the shoulders are turned away from target to the right about 45 degrees.

So, two conclusions, very tentative, from first reading of the thesis:
1. That's not a drive, that's a putt.
2. It's possible to get 50 mph without drive mechanics.

The 20 degrees is in reference to direction of throw, not target direction. The thesis indicated that the thrower is turning away from the target during the throw, which lines up with throwing understable discs to the left of the target.

 

[timothy42b]

The 20 degrees is in reference to direction of throw, not target direction. The thesis indicated that the thrower is turning away from the target during the throw, which lines up with throwing understable discs to the left of the target.

Are you sure? I went back and read it again. XsubN is "direction of throw." I used the word target but of course I don't know what the target was. It really seems to me that she was using direction of throw to mean direction the disc goes at release.

Google tells me that ultimate lids are understable. I didn't know that so thanks. But you mostly throw them nose up so they can be caught.

I also looked at elbow flexion again. In her study the elbow starts about 50 degrees flexed and peaks at 70 just before release, it never gets much below 50 through follow through. There is no way they get near a power pocket. This is essentially a one lever throw (plus wrist.)

 

[timothy42b]

Since the pull vs. swing abstraction is being talked about, I do think blayed is onto something that some forms may be more emphasizing a swing of the arm from the shoulder even if it's recruiting a lot or even all of the same sequence in the muscular sense. Some forms might be a little more emphasizing the pull - I think they're all still finding a way of shifting "past the door frame" and committing that chain that was pulled taut into throwing force once they land.

Thinking about Sara's emphasis on shoulder adduction, I was watching my playing partner during a round this weekend. On upshots I think it might be mostly shoulder adduction. There's some weight transfer but it doesn't look like it's driving the throw. And Simon's 40 mph throw that you posted on Hips could also be shoulder driven.

I looked at several tennis sites online. I don't know who's trustworthy and they differ more than we do, but they all referred to shoulder adduction as part of the tennis backhand. (there's some variation between people who refer to adduction and abduction and others who have positive and negative adduction, or I might be misunderstanding.)

 

[Brychanus]

^ Got interested in this. Shoulders are involved in the action too though this might vary a bit, and it's possible to overcook it and pull the body out of alignment. I think in general you want the arm swing to be aligned well with the shoulders as they swing through. Potential adduction vs abduction depends on which phase of the swing you mean, I think.

For instances, GG appears to have more pure shoulder-upper arm alignment:

We might see a little more shoulder (abduction?) action for Simon swinging through than some players:

Simon does a few things that are a bit exotic that get more torque coiled up in his form. I still like to point out that these mostly evolved after he transitioned from his younger pendulum vertical form.

 

[Brychanus]

Mmmm I think the shoulder abduction as you swing through the pocket can be part of the move. Always?