David Chan

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Hi,

As we start to push towards fall, time to start thinking about Movement Analysis and training again.

These are just some late spring turns at Squaw Valley. Shirley Lake Race area. (4th chute)

Shmedium to Short radius turns.

Remember, the goal here is to try to look at ski snow interaction, Ski performance, body performance. and try to leave out any corrective opinions. By learning how to do MA by breaking down actual movements, how the five fundamentals are being applied, etc, It really allows the observer to figure out what the cause is and then how they might affect an change/outcome.

Please remember I'm not looking for any specific fixes, drills or corrective items (but if you want to send me private messages with suggestions I'm happy to hear your observations) The goal here is to help people learn how to do effective observational Movement analysis.

You are welcome to ask questions if you need clarification.
 

karlo

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Turns to left, good articulation of all joints. Turns to right, quite stiff. Put another way, more angulation on left turns, more inclination on left turns. I think that causes the problem, below camera, in transition, resulting in being back on a left turn. After that bobble, the subject seems to pull it together, linking turns both left and right with good joint articulation, and a quiet upper body.
 
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LiquidFeet

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....These are just some late spring turns at Squaw Valley. Shirley Lake Race area. (4th chute)
....shmedium to Short radius turns.
....Remember, the goal here is to try to look at ski snow interaction, Ski performance, body performance. and try to leave out any corrective opinions. By learning how to do MA by breaking down actual movements, how the five fundamentals are being applied, etc, It really allows the observer to figure out what the cause is and then how they might affect an change/outcome......
I see consistent shortish radius turns in what looks like dense, settled spring glop that used to be bumps.
The blue pitch (?) gives skier some speed.
Skis are not sinking deep into the snow, but they are embedded in it, not floating on top. Guessing Head Titan, shortish turn radius, waist 80?
General turn radius is being heavily influenced by the bend in the ski, although some muscular rotation is happening at the top of the turns.
In a few turns the skis are moving diagonally across the snow (ex: 0.13-0.15), in others they are slicing through it with tails following tips.
Skier's head is up and he is looking where he is going.
Stance width is narrowish and stays constant during the whole run.
Tip lead is minimal.

Snow spray in the frame below indicates the both skis are engaged. The spray comes off the fronts as well as the backs of the skis, indicating skier is centered. This snow spray pattern appears to be fairly consistent throughout the run, indicating the skier is keeping impactful weight on the inside ski. Depending on the snow, this weight distribution may be helping with what float there is.
Screen Shot 2019-08-22 at 8.09.18 AM.png


I'd like to see a side view taken by a videographer moving alongside the skier. This is needed to determine if the skier is moving fore-aft along the skis through each turn. Only a profile shot offers certainty. My first guess is that the skier is working to stay centered fore-aft through the turns.

But in the shots below, the only side-ish views in the video, the skier's ankles appear to be open. Spine tilt does not match shin tilt. Perhaps the skier is moving the skis ahead to load the tails here at turn's end, in order to get them to grip. Not enough side-views to see if he is doing this consistently or not.
Screen Shot 2019-08-22 at 8.21.54 AM.png
Screen Shot 2019-08-22 at 8.53.41 AM.png

Skier releases old turns and initiates new ones by lengthening and shortening each leg simultaneously. As a result, his body moves up and down a bit with each turn. He also tips the new inside ski to its little toe edge ahead of the outside ski, as in the frame below. This makes him look bowlegged momentarily, and functionally keeps his skis parallel during initiation. He also rotates the skis around in the top half of the turns, using femur rotation. This gives the top of his turns a tighter radius than the bottoms.
Screen Shot 2019-08-22 at 8.34.21 AM.png

Maximum underfoot pressure happens a bit after fall line, about here in the frame below. In some turns the skis slide out a bit as the skier sinks lower and this pressure maxes out. Frame below 0:11.
Screen Shot 2019-08-22 at 9.12.36 AM.png

After this "pulse" the skier quickly initiates the next turn.
Pulse, release, pulse, release. This change from old turn (with body low and maximum underfoot pressure) to body moving up (with skis lightened) is quickly executed.
Screen Shot 2019-08-22 at 8.12.28 AM.png


Skier's upper body stays quiet. He is limber enough at the hip sockets to bend forward there, and to rotate his femurs there. The spine stays stable without twisting or bending down and straightening up. His angulation directs pressure to the outside ski, but not totally.
Screen Shot 2019-08-22 at 8.27.36 AM.png Screen Shot 2019-08-22 at 8.27.27 AM.png

There's a whoopsie at 0.19. Looks like one of the skis hit something. Does not appear to be caused by skier imbalance. Followed by quick recovery.Screen Shot 2019-08-22 at 8.29.33 AM.png

Hand-arm-pole management is consistent, excluding the one frame above. Elbows are out, hands stay out and a bit below elbows. Right hand flicks pole basket ahead to plant it in front of toe piece, left hand does not do this and consequently basket taps snow behind foot. I see no unfavorable consequences in ski-snow interaction from this lack of symmetry in this run. If this is an habitual pattern, this asymmetry impact other turns on different terrain and in different conditions.

I don't look at turns through the filter the PSIA five fundamentals provide. I prefer to do what I just did. I would use that filter for MA in a certification exam, however, since that's what they want.
 
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karlo

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Ok, we’re on our way home from our beach vacation and the alternator goes, just as we’re headed out and just as we come upon a service station. It’s a 2-1/2 hr job. The Good Wife has transferred into the vehicle our daughter is driving and they’re on their way home. Me, I’m waiting for the job to be completed and relegated to a local bar,

0ABD96D4-7E25-43B4-879C-44D7C7186BE1.jpeg

and, bar

636F9A86-6CDB-41FE-A5C6-7FEA20D46F01.jpeg

What’s a guy to do?!

Reading @LiquidFeet ’s post, ohhh! That’s what advanced MA is!

Ok, I’d better expand on my previous observations . Looking uphill, here’s the transition going into the well-articulated left turn,

B294ADE9-5166-4345-AE37-92CE92A92500.png


And, here’s the transition going into the stiffer ( I would also say more rushed) right turn,

5B0514C7-A937-4B2A-974F-BF018D426A9B.png


In both cases, the stance is solid. Good athletic platform. The difference, I believe is where the transition is relative to the fall line. In the former, the skis are pointed more across the hill. In the latter, the skis are pointed more down the hill. I.e., the left turn, though made with good articulation, is incomplete.

Below the camera, here are the two transitions. The one going into the left turn,

310EBCCE-10B3-4099-BAA1-5496A427C202.png


and, the transition going into the right turn.

F707E950-A2FD-4B7A-A810-83F377302B98.png


The subject now seems to be skiing more directly down the fall line, but the transition going into the right turn is still, compared to the other, more pointed downhill, as seen by both ski direction and upper body-lower body rotation (this subject has no problem facing downhill). Despite the difference, the problematic transition is still pointed more across the hill than it was uphill of the camera. Here, downhill of the camera, both left and right turns now have smoother transitions and are more symmetrical; turns are nicely linked. Both left and right turns start relatively high, with apex at the belly. Upper body is much quieter.

BTW, I didn’t catch it watching the video, but looking two photos up, it appears that the skis got lifted by and the new inside ski is coming down first, which suggests to me that the subject is not shifting pressure to the new outside ski in transition, rolling from little toe edge to big toe edge on the new outside ski.

Does this count as MA? Or, does it lean too far towards prescription?
 
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David Chan

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Does this count as MA? Or, does it lean too far towards prescription?
Lots about stance, some about timing and tactics. How about some more info about turn mechanics, ski/snow performance, and body (be specific about which joint/s, body parts) performance? Try not to inject (much yet anyway) what to fix. Just what's going on.

Not to say you are right or wrong, however beside the pitch coming towards the camera, there is a side pitch where the left side of your screen (facing up hill) is higher than the right, (side hill). I know the camera doesn't really show that but if that weighs in to your analysis, or helps you with what's going on...

And the comment about "advanced" for the subject, this level of MA might be something you'd get in a L3 exam or maybe a high functioning L2 candidate may get this skier for MA. A L1 or practice L2 exam would not be as high level. Lots of subtle things going on.
 
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David Chan

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Also as much as I’ve tried to become more symmetric in my left-right I’m sure it has a ways to go. I did break a Femur a while back and while I am convinced that the surgeon did a fantastic job of getting the alignment right, I’m sure there are things still showing as asymmetry in my skiing. And of course we all have some asymmetry in our skiing. We are human after all.
 

Bad Bob

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Also as much as I’ve tried to become more symmetric in my left-right I’m sure it has a ways to go. I did break a Femur a while back and while I am convinced that the surgeon did a fantastic job of getting the alignment right, I’m sure there are things still showing as asymmetry in my skiing. And of course we all have some asymmetry in our skiing. We are human after all.
Broke your right one? That would explain the favoring at 10 seconds and 19.
 
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David Chan

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Broke your right one? That would explain the favoring at 10 seconds and 19.
The turn at 10, and 19 I think were more a symptom of terrain, not favoring one leg over the other but who knows. I don’t consciously favor either. If anything I should have been favoring the left. I strained an mcl and hamstring on my left leg and a minor LCL strain on the right leg during the Division Trainer in March. There was probably a little more pain on my left leg on this day. Getting old sucks. It takes a lot longer to heal these days.
 

rustypouch

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My initial thoughts (that doesn't seem to be have mentioned yet) are that everything is happening too late in the turn.

A clear sign is that the skier is holding onto the turn too long, with the maximum pressure happening towards the end of the turn, and the skier stays on his edges and traverses a bit between turns.

As a cause/effect (depending on how you look at it) the skier isn't engaging the new edges until the skis are pointed down the fall line, instead of at the top of the turn.
 

karlo

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there is a side pitch where the left side of your screen (facing up hill) is higher than the right, (side hill)
So, looking uphill at the subject, if one drops a ball, it rolls down and to the right?

this level of MA might be something you'd get in a L3 exam or maybe a high functioning L2 candidate may get this skier for MA.
I think I’ve given one lesson since getting L2; and, I haven’t taken an MA course yet. Most of what I know is from reading about it here at Pugski. So, I’m both disadvantaged and privileged :)
 
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David Chan

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So, looking uphill at the subject, if one drops a ball, it rolls down and to the right? Yes



I think I’ve given one lesson since getting L2; and, I haven’t taken an MA course yet. Most of what I know is from reading about it here at Pugski. So, I’m both disadvantaged and privileged :)
We all have to start somewhere.
 

LiquidFeet

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....
I think I’ve given one lesson since getting L2; and, I haven’t taken an MA course yet. Most of what I know is from reading about it here at Pugski. So, I’m both disadvantaged and privileged :)
Karlo, congrats on that L2!
 
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David Chan

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Yes. Agreed. Congrats on the L2. Not a gimmee by any stretch.
 

geepers

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So, looking uphill at the subject, if one drops a ball, it rolls down and to the right?



I think I’ve given one lesson since getting L2; and, I haven’t taken an MA course yet. Most of what I know is from reading about it here at Pugski. So, I’m both disadvantaged and privileged :)
Well done.
 

razie

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Looks to me that the release is mistimed and the skier's jamming the boots, sent flying over the handlebars often, especially on that variable snow. Part of the reason is that the upper and lower body are coupled too much. It gets actually quite a lot better in the last 2 turns, which are the best in this run: there is still a push to get off the ski, which could continue to cause trouble on that snow, but there is some counter and flexion to smooth things out, as the turns quicken.
 

karlo

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Thanks all.

How about some more info about turn mechanics, ski/snow performance, and body (be specific about which joint/s, body parts) performance?
I'm not going to read other MA's for now, after having read Liquidfeet's. Doing so would make it an open-book exercise.

Looking uphill, the transition is smooth. But, I get a sense that these are static turns. Edges get on a certain angle and just stay there. Getting to that angle is smooth, but once there, it stays there for a big part of the turn before beginning to release for the next transition. "Park and ride" - took me a while to remember the term. I also get a sense that there is a strut, with the inside foot being projected forward as a means of shortening the inside leg. Regarding the pole plant, the right arm is not quiet. It swings forward at the shoulder to reach for the pole plant, then swings back. The left arm, the pole plant is almost non-existent. If fact, it actually is non-existent in at least one of the turns. And, this goes back to the inclination thing. The waist and all else above it are not consistently parallel to the plane of the slope.

Looking downhill, after the bobble, things edge angle increase and decrease become smoother. Perhaps this is because the turns are shorter and there is less opportunity to hold one edge angle; or, it could be intent of the subject.
 
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David Chan

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for overall "image" that's a good start. Read that to yourself and then close your eyes and visualize a skier doing that. Then watch the video again. Did you see that skier in your mind?
 

karlo

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for overall "image" that's a good start. Read that to yourself and then close your eyes and visualize a skier doing that. Then watch the video again. Did you see that skier in your mind?
Yes, I still see it. Reinforcing that impression of park and ride, I now paid closer attention to both upper body and lower body. At a point in the turn, they become static relative to each other, as do the two legs relative to each other.

Yes, I still see left pole plant missing in some places. Perhaps not totally, but effectively. I still see right arm swing from the shoulder.

Now, I feel like cheating and opening the book. :)
 

tube77

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Indeed this is very good opportunity for a skier like me who was never trained for the MA or learned ski by him/herself from youtube.
Before I forget what I observed I would like to start making some quick notes.

1. Pole plant.
The skier plant the pole mostly only on the right hand/arm.
He barely pole plant with his left hand. In a few straight turns he just dragged the left pole.
Also when he pole plant on the right side, he mostly moves his entire right arm forward rather without wrist movement.
His needs to more activate his wrist movement.

2. counter rotation or upper/lower body separation
I don't see much of counter rotation or upper/lower body separation for short turns.
His upper body or femur/pelvis looks very well aligned with the direction of the ski rather than constantly facing the down hill.
In this case, art frame drill using poles would help to fix the upper body down the hill.
Looks like he's mostly doing the medium radius turns.

3. No A-frame
His leg stays consistently in parallel without A-frame problem so that both tips move in a same angle.

4. angulation/inclination
I see the skier more inclined when turning to the left. On the other hand, he is more angulated when turning to the right.
 

JESinstr

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There's a whoopsie at 0.19. Looks like one of the skis hit something. Does not appear to be caused by skier imbalance. Followed by quick recovery.View attachment 78913

I don't look at turns through the filter the PSIA five fundamentals provide. I prefer to do what I just did. I would use that filter for MA in a certification exam, however, since that's what they want.
Those poor ole Snow Snakes, They get blamed for everything! :)

But let's take another look and this time use the 5 fundamentals.

The whoopsie turn begins with a hooking (bowed leg lead) of the new inside leg accompanied by an inward inclination (lean) of the upper body. Violation of Fundamental #2: Control pressure from ski to ski and direct pressure toward the outside ski . His inside edging movements and body lean at this point in the process produces a bias for directing pressure to the inside ski. This non-adherence also creates a divergence situation between the skis.
upload_2019-8-24_13-37-31.png


In regards to Fundamental #1 Control the relationship of the Center of Mass to the base of support to direct pressure along the length of the skis
With the divergence comes a "to the rear" bias affecting the COM-to-BOS relationship hence the need to rotate (Skid) the outside ski to try and "Catch up" with the inside as is evidenced by the resulting spray.
upload_2019-8-24_13-41-3.png


But it is a losing effort as tip lead increases and the ill fated, compensatory effort of pressing harder into the outside cuff just increases pressure to the front of the ski but does little to fix the fore and aft imbalance.
upload_2019-8-24_13-49-49.png


So when he hits an imperfection in the surface he is not centered and in no position to appropriately deal with the disruption.
Whoopsie!
upload_2019-8-24_13-56-0.png


In summary, this imbalance situation began with intentional moves to the inside prior to establishing a solid, centered COM to BOS relationship with the outside ski. I see this in a majority of his turns. Remedy: experiment with Inside Leg Extension (ILE) initiation and practicing the "Get over it" Drill, and work on active shortening of the inside leg.

In regards to Fundamental #3: Control edge angles through a combination of inclination and angulation . I agree with many of you, there is work to be done here.

In regards to Fundamental #4:Control the skis rotation (turning, pivoting, steering) with leg rotation, separate from the upper body . He does a fairly decent job with this but lateral separation issues are delt with by #3

Finally in regards to Fundamental #5: Regulate the magnitude of pressure created through ski/snow interaction. We need to realize that a SOLID centered stance, through the arch of the foot and the proper implementation of the hinge complex (Ankles/Knees/Hips) is priority one for effective regulation of pressure.
 

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