ThighMaster move from DG Spin Doctor

[Sheep]

I think the yellow line is the imaginary mathematical Axis of Rotation. The spine is not the axis, it precesses around the axis on a tilted spiral. The front leg itself is not really the axis either although it's close, the ankle is the base of the axis as everything pivots centered around it.

If the rear leg was the axis of rotation, then it would be moving/wandering around during the throw which would kill rotational velocity.
View attachment 338304

The rear leg kick impulse force really happens before it leaves the ground. Forces happen before motion.

The toe tap after disc release is recoil that happens from blowback from the brace/hit.

I'm not sure what fight you're trying to win so hard here. but... It's like. done, gone. nobody cares.

When I jumped into moderate and point out the problems, nobody cared about that either.

Lets be more constructive on other more important things.

 

[Brychanus]

I've heard they're average sex differences in some things like mentally rotating complex 3D shapes, where at the tails, men excel more but women excel more in other areas.

This is true in most studies I am aware and I like that you said "at the tails." For most very well-powered studies (thousands of subjects, so there are fewer of them) there are the classically taught splits in sexes, and discussions of gender/trans/other variables. It's always important to remember that the distributions otherwise highly overlap, and we still don't know how much is really attributed to environment/culture/upbringing/reinforcement etc.

That's awesome. I think we would all get on much better if more people adopted your outlook. I appreciate that a ton and strive to emulate it as much as possible. Have you studied Buddhist / mindfulness philosophy or did you get to where you are on your own? Admirable either way!


I think I'm following you on the "athletic resistance" point. Is the demo Josh does in his recent bracing video with his hands in his pockets hopping back and forth between feet while not moving his CG much what you're getting at? That is good athletic resistance, yes?

I agree on not overemphasizing anything, and I know its very easy for students to get hyperfocused on something small and miss the bigger picture. I think the adductor move falls into a 'maybe do it actively a bit to play with the idea' and then it will quickly become subconscious and that muscle activation will be more supporting good movement that causing it. I think that move falls into a 5% icing category rather than a 95% of the cake one... but at the same time I feel it is an understanding of those little cracks and corners of the movement that help me better understand and be able to teach the movement as a whole.

Hmm.. yea. "catching" is not good. "not dropping in the first place" is better. I like the idea of staying in balance, I think I need a level up on what exactly that looks like as the x step loads. That is kinda a weak spot in my understanding.

Yes! re:10 lines from 10 instructors. Me and Seabas have different ideas about where the axis is... including or excluding the front leg. As such it is difficult to understand each others thinking. I would love to clear that up, first step seems to be actually understanding what he thinks...

I think you are right that the hip adductors work together or not at all. My timing cue of rear leg and then front leg is probly more of a feel thing that a real physics thing. But I think that contraction of the adductors helps the weightshift more constructively bridge the gap from rear foot to front foot. I think we all agree on that point.

Brace firmness re:transient. Absolutely. It feels / looks to me as if you want everything to firm up (body tension) just before the hit. But In reality it seems to me that pro players have the rear leg kick just after release if I'm remembering right.

Thanks for the back and forth. Wish I had more time available to keep up!

Thanks man, good stuff to read in here. Yes, I did a brief stint with some Buddhist philosophy and a lot more time with mindfulness training, and physiological tone training via breathing and mentalization. Since I run on the "high anxiety and limbic" end of the spectrum, I learned a lot of tools to help my body and brain calm down. Even just 16 seconds of deep (diaphragmatic) breathing 4s in, 4s hold, 4s pause, and 4s hold before regular breathing has been shown to reduce sympathetic nervous system tone/calm people down. Easy to learn, hard to remember to implement. I teach it to all my classes since everyone is always stressed. I do it before I am about to do a stressful meeting, after 2 year old yells at me, etc. Helps more than you'd think.

I get what you mean @Sheep given the context of this thread. But in the spirit of "I'm just here for the mechanics," I did want to acknowledge that the below helped me get a refresher on how he integrates about all of the issues below, which I think gives clear points that people could compare, contrast, and discuss. I thought the tone was pretty neutral given where we all started

FWIW it took me a while to understand the balance line and "axis of rotation" distinction, which frustratingly in biology can apparently be in weird places in reality. I still don't completely understand it and based on a couple recent exchanges on my form thread I think we still need the smart biology modelers to help figure it all out.

The sidewinder version of the one leg drill is as he described. He uses this version to "verticalize" the axis of rotation from the ground to sky in this particular move. He also emphasizes swinging through the center and leading with the mAss, which is really a postural trick from other sports ideas.

I think other people's one leg drills have different concepts of (1) where the balance is slightly different and (2) where the use and sequence of body mass is different (again, I am going to talk to a couple people with data sources myself).

I do still suspect there is some player variance which is what I was tiptoeing into in my recent video and slightly different models for how moves can work. Notice I was VERY careful not to make any claims about right or wrong or novelty fwiw. Just my style.

Rather than "fight" about anything I suggest people just try to keep having a suddenly productive conversation. If they don't want to, they don't have to of course!

 

[Brychanus]

Quoting this again below so it gives ease of access to people.

Btw one of the reasons people have trouble understanding sidewinder is he reasons very abstractly like a physicist when he wants to.

When people argue about center of mass movement, sometimes they are talking about literal body mass.

They are not the same thing.

It's better when people actually talk about this stuff. I'm scheduling a couple calls because I am learning more and more about what people disagree about, but sometimes I cannot tell if it is just due to using a different frame of reference or not. That's my current project and I'll leave that there for now.

Enjoy:

I think there is a difference in coaching a specific student/fixing issues, vs general skill building instruction for the masses. Coaching one student might require specific advice or cue that would be terrible for another student, and the same advice or cue for two students with the same issue might yield two completely different results due to the differences in how people learn and/or physical differences between students. I'm not sure there is a OSFA One-Size-Fits-All method that will work for everyone. Lots of other sports have spent a lot more time and money and technology and there is still a lot of debate between those coaches' methods and styles.

I don't know about you, but I found absolutely nothing about the disc golf backhand to be natural or instinctual. If it was natural then I wouldn't bother to have learned as much as I can about it. The only reason I found forehand "naturally" is due to prior acquired motor skill throwing baseballs/footballs/skipping rocks etc. Even the "simple" act of walking is not purely innate or natural or instinctual, like breathing or swallowing. In fact walking is quite complex and complicated to explain how 200 muscles are being used. Some people forget how to walk, some walk inefficiently and could improve. That is not to say that all people will walk identically, because everyone is physically built differently, so their most efficient way to walk will be unique, but the same fundamentals can be applied.

When throwing, if you were to just keep your rear arm relaxed it will fly out and drag behind you when you transition into forward rotation due to inertia. It requires conscious effort to tuck the rear arm into the body while rotating. Imagine telling a figure skater to just let the arm/s relax and do what it does naturally vs telling them to tuck their arm/s into the body, or raise them overhead to spin even faster.

After the skill has been learned into memory, only then can they begin to focus on their performance and not focus on mechanics.

When I came back to throwing after a lower spine injury, I kept hurting it again because my rear arm was too passive and naturally dragging the shoulders behind the hips increasing lower spine torsion/separation. This was the time I started to experiment with the Marc Jarvis style rear hand on thigh which reduced the rotational separation/torsion on the lower spine and my spine finally stopped hurting and I was also throwing further with less effort all the sudden.

Powering through with your arms

I frequently have runners tell me that they have bad running form and I always think to myself, “Well, have you ever seen me run? I look like I’m about to tackle someone because my posture is...

www.runwithgina.com

"To be more efficient runners, we need arm drive to be turned on and this is accomplished by a balance between the muscles in the front and the back of the shoulder joint. As mentioned earlier, the shoulder joint is the most mobile of all joints so there are several muscles that contribute to movement about the joint but the prime movers for flexion (arm driving forward) are the pectoral muscles and the prime movers for extension (arm driving backward) are the latissimus dorsi and posterior deltoid muscles. Get these puppies in balance folks! In addition to decreasing the forward momentum of the body if the arms aren't driving efficiently, it will also allow for more twisting through the torso and pelvis.

In a 2008 study by Pontzer and colleagues, control of arm swing during running was investigated in a passive arm swing model vs an active arm swing model. In the passive arm swing model, subjects were asked to fold their arms across their chest, which in turn also decreased the moment of inertia. It was noted in the passive arm swing model that there was a lot of upper body movement, but it was not from flexion and extension at the shoulder joint as observed in the active arm swing, but from rotation coming from the torso. In an active arm swing model, shoulder musculature drives arm swing, but equally important, the arms act as mass dampers, decreasing rotational movements of the torso. Low back pain anyone?

Not only can the extra rotation of the torso cause low back pain when arms are not flexing and extending during running, observational research has measured larger joint angles at the hip, knee, and ankle when arm swing during running is not efficient (Miller et al., 2009). Not only is this not energy efficient, it puts the distance runner at greater risk of strain injuries."

I think the yellow line is the imaginary mathematical Axis of Rotation. The spine is not the axis, it precesses around the axis on a tilted spiral. The front leg itself is not really the axis either although it's close, the ankle is the base of the axis as everything pivots centered around it.

If the rear leg was the axis of rotation, then it would be moving/wandering around during the throw which would kill rotational velocity.
View attachment 338304

The rear leg kick impulse force really happens before it leaves the ground. Forces happen before motion.

The toe tap after disc release is recoil that happens from blowback from the brace/hit.

 

[disc-golf-neil]

View attachment 338304

This is a great picture to help see the tilted axis in still frames.

@Brychanus I think it would go well with your tilted spiral thread, also, what about Earth's wobble, could it be a useful to make the connection?

 

[Brychanus]

This is a great picture to help see the tilted axis in still frames.

@Brychanus I think it would go well with your tilted spiral thread, also, what about Earth's wobble, could it be a useful to make the connection?

Yeah nice dude. Sidewinder also just shared related images in my thread worth staring at for a bit so I'll consolidate all this stuff over there!

 

[TrebuchetDiscGolf]

Ok Quoting SW22's post for ease of reference.

I think the yellow line is the imaginary mathematical Axis of Rotation. The spine is not the axis, it precesses around the axis on a tilted spiral. The front leg itself is not really the axis either although it's close, the ankle is the base of the axis as everything pivots centered around it.

If the rear leg was the axis of rotation, then it would be moving/wandering around during the throw which would kill rotational velocity.

Dr. Yeager vid is time stamped to axis of rotation. He says the axis of rotation is about the front leg.
View attachment 338304


The rear leg kick impulse force really happens before it leaves the ground. Forces happen before motion.

The toe tap after disc release is recoil that happens from blowback from the brace/hit.

Ah Ok, I think I understand now. You are right. Your axis model is correct for the throw as a whole. I am also right in that my frame of reference is not the throw as a whole as yours is. My frame of reference is just the energy that gets directed into the disc. So my frame is timestamped from peak reachback tot he hit. That is the axis I am describing. In the way I am teaching the throw ( a Wiggins based model, rather than a SW22/GG vertical move, rather than a KK / Nick Krush brace in passing move) that axis of rotation is head to rear foot. Once my time frame ends then we transition back to your model being more useful for modeling the follow through. This is where my comments previously about the axis shifting came from, there is one relevant axis as I describe before the hit, then your front leg inclusive model takes over to handle the follow through.

In my coaching I don't worry about cuing he follow through. People need enough help getting the hit right so I focus on setting that up. Working on the assumption that if you do the hit right, your follow through will be workable.

SW22, do you feel like I'm on the right track to understanding your model?

 

[HyzerRoc]

Ah Ok, I think I understand now. You are right. Your axis model is correct for the throw as a whole. I am also right in that my frame of reference is not the throw as a whole as yours is. My frame of reference is just the energy that gets directed into the disc. So my frame is timestamped from peak reachback tot he hit. That is the axis I am describing. In the way I am teaching the throw ( a Wiggins based model, rather than a SW22/GG vertical move, rather than a KK / Nick Krush brace in passing move) that axis of rotation is head to rear foot. Once my time frame ends then we transition back to your model being more useful for modeling the follow through. This is where my comments previously about the axis shifting came from, there is one relevant axis as I describe before the hit, then your front leg inclusive model takes over to handle the follow through.

Sorry if I missed it but can you show a picture of what you are talking about when you say the axis of rotation is head to rear foot? Much easier to follow pictures than words with form for me.

 

[timothy42b]

I think I see what caused my confusion. It may have nothing to do with the TDG difference, dunno.

The SW22 bullriding pole rotates around that yellow vertical axis. The lower end is essentially fixed, the upper end describes a circle around that axis. The figure "swept out" would look like a cone, small end down.

But. The pole itself is rotating. So there is a second axis of rotation, and that one is moving.

 

[TrebuchetDiscGolf]

Well yea, the axis of rotation isn't stationary... on the top. The top of the pool cue moves around a bit from south to north. Whereas the bottom stays closer to stationary.







Magenta line is the Axis of rotation that creates the power going into the hit. The left hip folding in towards the right thigh, caused by the ground force in the brace.

Then an instant later the follow through starts and the axis shifts to the more vertical yellow line.

I focus my teaching on building an awareness of the magenta line because that is what I have noticed to be deficient in most AM throwers.

 

[TrebuchetDiscGolf]

And the point of the magenta line idea is that it allows the front leg to act as a piston resisting the ground and adding snap to the rotation around the magenta line. The front leg is NOT included in that rotation... but then it is included in the yellow axis an instant later. The axis shifts over time...

 

[sidewinder22]

And the point of the magenta line idea is that it allows the front leg to act as a piston resisting the ground and adding snap to the rotation around the magenta line. The front leg is NOT included in that rotation... but then it is included in the yellow axis an instant later. The axis shifts over time...

Not sure you ever saw my response to one of your other posts on the subject:

Like I've said before, it can get kind of weird applying some math concepts, so I understand the confusion.

I think the question you need to ask is, where are you are basing or anchoring or setting up your axis to rotate from most efficiently with a tight center like Simon, or catapulting the torso whip from like James Conrad?

If the rear leg is your axis of rotation then it's moving around during the throw which would kill rotational velocity.

View attachment 337821

I think a lot of the confusion is based on that you seem to be using a Free Rotation of Rigid Body definition that is Not stable or fixed or Braced to the ground, like throwing in outer space. In a throw we are Braced against the ground to give ourselves a stable or Fixed Axis of Rotation to orbit around. The axis of rotation is an imaginary line, it does not have to be through the whole body or leg, the axis of rotation does not rotate or move, everything rotates in a circle around it.

Rotation around a fixed axis - Wikipedia

en.wikipedia.org

"This type of motion excludes the possibility of the instantaneous axis of rotation changing its orientation and cannot describe such phenomena as wobbling or precession. According to Euler's rotation theorem, simultaneous rotation along a number of stationary axes at the same time is impossible; if two rotations are forced at the same time, a new axis of rotation will result."

The backswing Axis of Rotation is about the rear leg and the forward swing is about the front leg like I talk about in Crush the Can like Lizotte (should be timestamped to about 7min). Wiggins and Simon rotates around the front ankle during the forward swing. The spine and rear leg rotates/precesses around the axis.

 

[Jaani]

I'm not qualified to talk about the axis (here my vocabulary starts to lack). But I think there is one big myth to bust here publicly, and that is the hip hinge throwing anhyzers, would you agree Seabass? I mean, many people still adamantly suggest tilting the axis applies to hyzer only, right? Whereas, looking at Simon there, he seems to throw at least flat if not anny, and still hinges quite a bit. Am I right?

 

[sidewinder22]

I'm not qualified to talk about the axis (here my vocabulary starts to lack). But I think there is one big myth to bust here publicly, and that is the hip hinge throwing anhyzers, would you agree Seabass? I mean, many people still adamantly suggest tilting the axis applies to hyzer only, right? Whereas, looking at Simon there, he seems to throw at least flat if not anny, and still hinges quite a bit. Am I right?

Yes, you still hip hinge posture on all shots. The balance of the tilted spiral changes to the shot.

I think Simon would say he was throwing flat there, but it's slightly hyzer.

Most top pros throw about 20 degrees hyzer for what they consider "flat".

Straight & Flat Swing Plane Does Not Exist!

So I think a lot of players really struggle finding that effortless distance because they are trying to throw straight and flat by pulling the disc with the arm in a straight line and trying to manipulate the spin of the disc flat by actively curling the wrist and arm into horizontal flexion and...

www.dgcoursereview.com

 

[Jaani]

Yeah, exactly what I thought. Even annies (the actual shot shape) are basically flat releases. Because this is very confusing for amateurs. They think, to throw an annie you have to lean on your back...

 

[Brychanus]

All interesting and I'll cross link some axis chatter to the spirals and tilted axis thread. I think I'm starting to understand better why trebuchet and sidewinder don't agree about axes. A major difference is that sidewinder encodes the CoG/CoM as part of the concept.

There's some interesting variance in details, but here was a sketch where I was interested in the posture and arm angulation. Approaching max distance the body is usually moving such that "anhyzers" even pitch slightly hyzer (I'm not really saying anything different than sidewinders image above, just emphasizing arm angulation at and near the release point which contains information about the gravity effect in the move). You can describe that the axis of rotation seems to be the "principal component" of how most pros control the move. It's interesting how power shots are usually exploiting a bit of a bit of hyzer gravity advantage. Watched in real time, there's some interesting action late in the hand/wrist motion/tip of the whip in most pros that is important to the final release angle.

Post in thread Repository of Cool Images

 

[Dr. Steve Brule]

Isnt Simon basically leaning backwards here demonstrating an anhyzer?

 

[disc-golf-neil]

Isnt Simon basically leaning backwards here demonstrating an anhyzer?

Imo it feels and looks like he's leaning back, but there's a temptation to lean forward to be in a more athletic stance and in order to resist that temptation you have to feel like you're leaning back just to stand up straight, which is what it looks like he's doing to me when I look and think through that lense. Compared to a roller where you are really leaning back if you need it to come out on a lot of anny.

And this is why people with the TechDisc are often surprised that when they feel like they're leaning back a lot, they're barely getting a flat release angle when it feels like they are throwing a lot of anny. But most of the time you only need a flatish release angle for a lot of turn so it's fine.

 

[timothy42b]

Isnt Simon basically leaning backwards here demonstrating an anhyzer?

If the East/West spine tilt controls the hyzer angle, what controls the elevation angle? North/South tilt? Because sometimes we need to throw level or below, sometimes much higher?

 

[jupiterboy]

If the East/West spine tilt controls the hyzer angle, what controls the elevation angle? North/South tilt? Because sometimes we need to throw level or below, sometimes much higher?

I think the more lean/steeper hyzer angle the more you have to be able to control speed and grip. Disc selection, also critical. It's basically how you would throw a spike hyzer, but if you have a flippy disc and accelerate it well it can flatten out to a low bullet. If I'm not warmed up and throwing like this, I'll often burn them into the ground or sky the shots. Messy.

 

[disc-golf-neil]

If the East/West spine tilt controls the hyzer angle, what controls the elevation angle? North/South tilt? Because sometimes we need to throw level or below, sometimes much higher?

In Drew Gibson's reclaiming the crown episode one he throws a little too low and on says he is going to try to tilt his shoulders to angle more upwards to correct that.

Other than that, lots of people think about reachback height and pulling through on that plane, e.g., lower reachback = steeper upwards pull through.

If you stand perpendicular to where you are looking and you look up, you'll notice you sidebend and tilt your shoulders on an upwards angle. I think focusing on the Y axis much harder, like you would focus on a higher or lower chain link for putting, is the easiest way to intuitively control the launch angle. I often remind myself though that on hyzer flips I have to aim/look lower on the Y axis than I want to throw because hyzer angles are easier to throw higher. This is why Paul U recommends looking at the ground but a decent ways in front of you for hyzer flips. You don't have to look down very far to look at the ground far away, but it removes the temptation to look at the height you want the disc to be when it's out there which often ends up resulting in throwing too high. Or if I'm hyzer flipping and looking at a tree that's closer that I want the disc to turn to the right of, I look a few feet lower on the tree than the height I want the disc to be at.

When I throw more extreme hyzer flips, the more I hyzer the easier it is to throw higher than I want, so in addition to the above I also raise my reach back a bit more. If you hold your arm out in front of you with elbow extended and the arm parallel to the ground, then bend forward at the waist (hyzer lean) you'll notice your arm is pointing more downwards which will create an upwards arc follow through.

I think many good pros have a really consistent reachback height even when they are adjusting their launch angle though to minimize the amount of changes and rely more on the body tilt to give them the launch angle but for me, I think when I do a lot of hyzer lean I am more tempted to let my reachback become lower and so I have to think about raising it to keep it the same height. E.g., hyzer flip with like 30-40 deg hyzer and a really flipping disc to get around a corner and then late flip to flat.

Some pros have a really low reach back as a default, which if they pulled through on that same angle would always be throwing high, so I think in this situation they level out that angle during pull through to throw lower heights. Ezra A doesn't reachback this low normally but it's an exaggerated demo he did:



Here's AB throwing a low-medium height hyzer on top and then a like 70 degree plus launch angle spike hyzer on bottom, reachback height looks pretty consistent but arm height in 3rd picture of the spike hyzer looks a bit lower but it's hard to tell from the different camera angle. Shoulder tilt difference is very noticeable though.