Disc Golf Course Review - The Twitch of the Hips

Disc Golf Course Review (https://www.dgcoursereview.com/forums/index.php)

- Technique & Strategy (https://www.dgcoursereview.com/forums/forumdisplay.php?f=4)

- - The Twitch of the Hips (https://www.dgcoursereview.com/forums/showthread.php?t=137717)

Quote:

Originally Posted by dreadlock86 (Post 3646263)

haha, you pinned him on the Oman thing so now he's arguing about levers again

How's the popcorn on the sidelines? Did they get enough butter and salt for your likening?

Quote:

Originally Posted by RocHucker (Post 3646315)

Mechanical engineer here, though I am plateaued at 375ish ft of max RHBH golf distance.

Assuming that one end of the "lever" is fixed at the center of rotation (what we're discussing as an approximation of our arm during the disc golf throw, though I suspect not an exactly accurate one):

A longer lever will translate to a faster linear speed of the disc *assuming an equivalent rotational speed*.

HOWEVER, I'm not sure that we can assume equivalent rotational speeds between short lever throwers and long lever throwers. In part because it takes more energy to accelerate the longer lever in this scenario, due to the fact that the Rotational Inertia (a measure of the amount of energy it takes to increase rotational speed) of an object increases as you move mass further from the center of rotation. I'm guessing that this is why the bent elbow backhand throw (like McBeth) has greater distance potential than the swedish style (like Feldberg). Bent elbow style keeps mass closer to center of rotation to make it easier to accelerate rotation, but then extends the elbow at the last moment in order to maximize the lever arm (increasing linear velocity of the disc).

All that being said, I'm not entirely sure that this is a very relevant discussion. It's pretty easy to maximize lever length (extend the arm) and I don't think that anyone is arguing against a long arm at the point of release. The difficult part, and the part that Rodeo is constantly at odds with the rest of the community on, is how to best achieve rapid rotational acceleration (how to spin really fast). Ultimately, the physics say that that *is* what is needed in order to throw far. And those in this community who have demonstrated that they can do this successfully have repeatedly said that the way to achieve that rapid rotational acceleration is by making a linear shift and then bracing against the front leg.

Now if only I could do that correctly :wall:

I agree with what you are saying about mass and rotation. Thanks, that's what I have been trying to say. I agree that there is a linear shift into a brace. My whole point is that before that linear shift happens at strong brace, there must be some initial rotation coming into that brace, otherwise there is no rotation that can be used to turn the torso around. Slow motion video of pros proves this fact.

Quote:

Originally Posted by RoDeO (Post 3646236)

So, it really comes down to strength. That is precisely why Bob Feller could throw as hard as Chapman despite diffetent lengths of levers. They were both putting in the same force which is right at the brink of what the human body is capable of.

I just need to add 41lbs of muscle and 14" of vertical and a new pair of ankles.
https://www.menshealth.com/fitness/a...f-tim-collins/
https://hips.hearstapps.com/hmg-prod...1445495401.jpg

A K-Vest performance graph for a baseball swing: The left-most vertical line represents "heel strike," while the red line represents rotation of the pelvis. From the graph it appears there is some amount of counter-rotation going into heel strike (below the x-axis) with a great deal of rapid rotation after heel strike. The second vertical line represents "first move," when the hitter's lead hand begins to rotate forward. It appears from the graph that at this point, hip rotation is near 0 degrees.

Heel strike: "this is meant to show when the hitter’s foot is planted and getting close to launch position."

This graph and the analysis in the article seem to support the position that the positive (targetward) rotation of the pelvis happens after heel strike/foot plant.

https://www.dgcoursereview.com/forum...ictureid=39076

"With the availability of 3D technology like K-Vest, we can now measure and see exact body positions throughout the swing—in real time. K-Vest provides a basic report that displays a hitter’s kinematic sequence and body positions at three different swing phases. This article dives deeper on what K-Vest has to offer by providing a framework for evaluating the performance graphs and the body positions associated with them."

Evaluating a Swing Using K-Vest Performance Graphs

From the same article, a discussion on torso side bend at the point of heel strike:

"Hitters who are “uphill” at this point in the swing (blue line swooping well above the x-axis) tend to hang back, which limits the ability to transfer weight to the front leg. These hitters gain little ground in the swing and also tend to “shift” their hips upon heel strike rather than immediately block with the front leg and go into rotation. These hitters are setting themselves up to “collapse,” which delays rotation, causing an arm dominant swing that can have trouble with the pitch up in the zone."

It would seem that this part of the article calls for shifting to the front leg, bracing/blocking, then going into rotation.

Quote:

Originally Posted by SaROCaM (Post 3646358)

That's why I like to look at the video evidence. Ozuna, perhaps the best slugger in the game right now. Looks like that hip is rotating before heel and brace plant. BTW, this was a home run swing.

https://i.makeagif.com/media/10-20-2020/LEokd8.gif

Quote:

Originally Posted by RoDeO (Post 3646363)

We know that it is possible to swing/throw in that manner. The article even speaks to variation based on adjusting to pitches vs. hitting off a tee. You have contended that it is impossible to swing/rotate if it doesn't start before the plant. This analysis supports the opposing position that it is indeed possible to shift, then plant/brace, then rotate.

Quote:

Originally Posted by RoDeO (Post 3646363)

That's why I like to look at the video evidence. Ozuna, perhaps the best slugger in the game right now. Looks like that hip is rotating before heel and brace plant. BTW, this was a home run swing.

Furthermore, the article speaks to "an arm dominant swing that can have trouble with the pitch up in the zone." So if the pitch isn't up in the zone, the swing can still be effective despite being "arm dominant." Even if it is up in the zone, the best hitters can adjust, and strong hitters can overcome with strength. Just like how it is possible to strongarm a disc 350' or more to overcome suboptimal positioning/sequencing. Yes, it works, but is it ideal? Or is it arm dominant? (That doesn't mean it is all arm, just arm dominant.)

For disc golf, we aren't needing to adjust to a pitch; rather, we have the disc in our control. So there is less reason to have variance from what may be ideal.

Quote:

Originally Posted by SaROCaM (Post 3646368)

May be possible but it never happens in disc golf and rarely happens in baseball.

So, here is a typical Paul Mcbeth swing. Have his hips started to rotate before his front heel comes into contact and strong brace? Yes. There's no refuting the evidence.

https://i.makeagif.com/media/10-21-2020/2sZQBP.gif