On Arm/Shoulder Ratios
This could also go under "
can anyone throw 500'?" but I intended it in a slightly different spirit since it's not really meant to inflame a debate about the "correct" model for determining max potential distance. IMO it's a multivariate problem like discussed the video at the top of the 500' thread and part but not all of what inspired my Expectations & Pushing Limits.
But one thing that's hard (for me) to object to is the idea that lever length matters for distance potential. Long levers matter, and intuitively especially the ratio of arms to shoulders. Shorter levers whipping longer levers should generate the most total leverage. So if you want "ideal" levers on the top line of the body, you want really long outer levers (fingers/hands>forearms>upperarms, relatively speaking) and relatively short inner levers (narrow shoulders).
I had some idle curiosity about this, so I went looking around for anything resembling data on the physical stats of players. Of course, there's not really anything useful out there. You hear anecdotes and can find the occasional speculation about
Ape/Gorilla Index (Wingspan/height) but even that's hard and doesn't necessarily correlate perfectly with arm/shoulder ratios. I definitely couldn't get anywhere with arm/shoulder ratios specifically. Anecdotally, it always looked to me like the furthest throwing pros tended to have longish arms and narrowish shoulders regardless of their height, but the eyes can deceive.
An Entirely Unprincipled but Potentially Interesting Thing
I took a painfully unscientific look at the follow through of various players the other day that ended up being more interesting than I anticipated. The angles, postures, etc. are impossible to square up perfectly, but I snipped images of various players and attempted to scale them somewhat reasonably. More importantly, I attempted to get snapshots when their arm was reaching peak extension into follow through viewed from the rear of tee when the shoulders were
sorta oriented to the camera. That allowed me to get a crude arm/shoulder ratio. I took the entire shoulder width relative to the throwing arm to help mitigate a bit of error variance trying to get a measure from the spine to the throwing shoulder, and I think the whole shoulder width functions like a lever in good form anyway.
I learned a few things from this. First, I wish I had a set of normative images/data (from adult population), which I might return to from player form reviews. But I had the benefit of my own image handy and compared it to some big guns.
Compared to those dudes, I look like a T-Rex. I expect that I'm on the low end of the distribution and there's a lot of imprecision in these images, but my guess is that the arm/shoulder ratios of all of these top guys are probably at the extreme high end of the population. From that vantage point for DG, I'd much rather be 5'7'' McBeth than 6'1'' me (yes, throwing the disc from a slightly higher release point will probably get a little distance, but I'd suspect it's much smaller than the lever advantage. Further speculation: maybe another reason McBeth likes to use that high arm slot when he can).
I was interested to see GG with the "least favorable" ratio among top throwers, but recall that he throws with an exceptionally large shoulder angle and late & large forearm supination, increasing his leverage into the hit and it's probably not a coincidence that he maximizes those mechanics throwing on hyzer.
Bonus image of SW22 afterward, who stacks up favorably in this specific dimension compared to a total Stumpasaurus like me, but would still need some surgery/bionics to catch those guys regardless of height.
One could get further meticulous and break this down by each part of the arm, but the procedure is faulty enough already that I didn't want to kid myself.
Anyway, enjoy (again, the ratio is probably the closest thing to interesting, ignore the raw inputs):
What's the moral of this story? I dunno. Maybe:
"Put in the work and enjoy the game."
