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MA please. Spinal engine vs lower extremity engine theory - Page 3

post #61 of 84
Quote:
Originally Posted by LiquidFeet View Post
 
Quote:
Originally Posted by chad View Post

Starting with a principle from physics: It is easier to add stages to an already functional sequence than to go back and modify earlier steps

 

Looking at movement development: natural meaning, without instruction, shaped  by our time moving in our world.

 

Stage 1: primitive reflex control.  I'll spare you the ins and outs.  they are autonomic, endowed to us.  We are born largely under developed and these are the baseline of our movements.

Stage2: we develop connections up to the midbrain/higher levels.  we begin to move based of desires, intention, e tc. Gaining head control, gaze, progressing up too standing and walking.  The development of these movements is based on teh inhibition of the stage 1 patterns.  They don't disappear, that are inhibited.

Stage 3: we gain access to the upper brain.  We are conscious of our movement, creative adjustments, etc. Final develpment is based on the movements and inhibition of the lower patterns.

 

That is a very rough outline.  the main point is we develop by not only gaining structural strength but also by inhibiting patterns that may be counter productive to our ability to move.  With relation to skiing, the autonomic patterns are still there, when we are in survival mode they fire.  They may not appear int he same format of extremity sequences but they interfere with the coordination of our movement.  Because they are largely directing spinal orientation they interfere with the dynamic control of the spine.  The spinal engine theory supports tthat the most efficient movement incorporates as many segments/joints as possible.  I was looking to see if there were any training programs designed to look at spinal mobility/coordination.  there is plenty of training for strengthening, but are there any land based or on snow programs looking at educating a person on these interfering patterns and how to identify and inhibit them.  thanks for any feedback. hope that is clearer.  I thought looking at MA for the trunk and spine would have been helpful, maybe it was just confusing. Maybe this is ridiculous all together.

There's the issue of "functional tension."  This term gets bandied about amongst ski instructor circles.  Here are three maneuvers that illustrate what it means.

 

Two people face each other on flat snow.  One is on skis (Skier); the other is not (Boots).  Boots grabs Skier's ski tips and pulls them forward.  Skier flails backwards.  Boots asks Skier to tighten the core, naming this "functional tension."  "Tension" because the core is tight enough to withstand another jerk; "functional" because the core is loose enough to move the right amount to not flail backwards.  Boots pulls skis forward and backward.  Boots continues pulling and pushing the ski tips until Skier is able to balance and not flail.  "Functional tension" has been achieved.

 

Another one of these:  Boots has Skier hold two poles horizontal out in front of body.  Skier assumes "functional tension" in whole body, including arms  Boots pulls poles forward and pushes them backward.  Skier's skis need to move fore and aft with the poles;  Skier's stance on skis, including arms, should remain stable.  If this works, Skier has "functional tension."  

 

One more:  Skier stands with poles horizontal, only this time stands in a countered position; one ski a little forward, same for hip, shoulder, arm, and hand on that side.  Boots attempts to twist poles and thus pull Skier's upper body to either side out of that countered position.  Skier's task is to maintain the countered stance, and not allow the arms no core to turn to the side.  If this is successful, then there's functional tension there.

 

Functional tension is not static when Skier skis.  Skiers upper bodies and lower bodies move in relation to each other.  But functional tension should accompany that movement.  Point of all this:  skiers who ski with functional tension are going to be more balanced throughout their turns as they encounter unexpected terrain challenges.  

 

Something else happens, too.  The core, with its tension intact, becomes a strong active player in the body's actions as a whole.  It stops being a passive reactor.

 

Is that something like what you were looking for in the blue above?


Edited by LiquidFeet - 1/13/14 at 3:59pm
post #62 of 84
Thread Starter 
Quote:
Originally Posted by LiquidFeet View Post
 

 

Chad, I have a theory that people in survival mode point their toes, i.e., they plantarflex.  Is there any research on this?  Am I crazy?  My newbie adults do it day one.  The open up those ankles... pressing their calves into the back of their boots (a clearly self-defeating action on skis).  I'm wondering if this is a learned behavior issuing from walking on dry land for many years, or something else... perhaps your "primitive reflex control."  Do you know?

look at the response of the tonic labyrinthine reflex with regard to primitive patterns, head velocity goes back(sliding down hill) if there is no familiar pattern to rely on than some of that motor pattern fits your issue with new students. It shouldn't be totally relative, there should be some variations in the response since they at least are able to move. 

 

thanks for the info, I have read some stuff here with regard to functional tension, it still seemed highly vague, although a cool sensory drill, I guess I was imagining something had been developed along the lines of the lower body analysis to teach skiers where their trunk restrictions and coordination could be refined and how they could relate that to their skiing.

post #63 of 84
Quote:
Chad, I have a theory that people in survival mode point their toes, i.e., they plantarflex.  Is there any research on this?  Am I crazy?  My newbie adults do it day one.  The open up those ankles... pressing their calves into the back of their boots (a clearly self-defeating action on skis).  I'm wondering if this is a learned behavior issuing from walking on dry land for many years, or something else... perhaps your "primitive reflex control."  Do you know?
Don't know about the plantar flexing but they definitely throw arms back and lean back. Pretty much like when slipping on ice while walking.
I always show people the emergency position. Grab your knees and if you can't turn out of it then bail to side. Adults resist the knee grabbing or holding even while just moving along. Sometimes I'll tell them to touch their knees and the hands go to the thighs. And that after we've been through it not moving.

I think there may be something to people not "having their feet" - they slip so the ground reference is off This throws the whole system off as people over ride the balance system with panic. Their reactions are 10x what is needed and just creates more problems.
I have no study evidence to back that up, just observation.
Honestly, if we could somehow dial down most peoples reactions with substances yet keep the coordination, they'd learn much quicker.

Ideally, initial learning would take place in a gently sloping flat single fall line slope with a rise at the end so they will stop. I'd have people just go straight and get used to gliding. Do that for 1/2 hour to an hour. Longer for some. That way they'd shut down a lot of the panic response. .
post #64 of 84
Quote:
Originally Posted by Tog View Post
 
Quote:
Chad, I have a theory that people in survival mode point their toes, i.e., they plantarflex.  Is there any research on this?  Am I crazy?  My newbie adults do it day one.  The open up those ankles... pressing their calves into the back of their boots (a clearly self-defeating action on skis).  I'm wondering if this is a learned behavior issuing from walking on dry land for many years, or something else... perhaps your "primitive reflex control."  Do you know?
Don't know about the plantar flexing but they definitely throw arms back and lean back. Pretty much like when slipping on ice while walking.
I always show people the emergency position. Grab your knees and if you can't turn out of it then bail to side. Adults resist the knee grabbing or holding even while just moving along. Sometimes I'll tell them to touch their knees and the hands go to the thighs. And that after we've been through it not moving.

I think there may be something to people not "having their feet" - they slip so the ground reference is off This throws the whole system off as people over ride the balance system with panic. Their reactions are 10x what is needed and just creates more problems.
I have no study evidence to back that up, just observation.
Honestly, if we could somehow dial down most peoples reactions with substances yet keep the coordination, they'd learn much quicker.

Ideally, initial learning would take place in a gently sloping flat single fall line slope with a rise at the end so they will stop. I'd have people just go straight and get used to gliding. Do that for 1/2 hour to an hour. Longer for some. That way they'd shut down a lot of the panic response. .

Oh yes, same thing here.

Oh my that would sure help.

In my dreams!  At my hill it's turn to a stop or plunge into something unfriendly.  Before we push off, I demo the emergency stop:  sit down to the side on your hip!  Then I get to demo getting up. Works just fine, and they all laugh.  


Edited by LiquidFeet - 1/13/14 at 6:56pm
post #65 of 84
Thread Starter 
Quote:
Originally Posted by Tog View Post


Don't know about the plantar flexing but they definitely throw arms back and lean back. Pretty much like when slipping on ice while walking.
I always show people the emergency position. Grab your knees and if you can't turn out of it then bail to side. Adults resist the knee grabbing or holding even while just moving along. Sometimes I'll tell them to touch their knees and the hands go to the thighs. And that after we've been through it not moving.

I think there may be something to people not "having their feet" - they slip so the ground reference is off This throws the whole system off as people over ride the balance system with panic. Their reactions are 10x what is needed and just creates more problems.
I have no study evidence to back that up, just observation.
Honestly, if we could somehow dial down most peoples reactions with substances yet keep the coordination, they'd learn much quicker.

Ideally, initial learning would take place in a gently sloping flat single fall line slope with a rise at the end so they will stop. I'd have people just go straight and get used to gliding. Do that for 1/2 hour to an hour. Longer for some. That way they'd shut down a lot of the panic response. .

All extension Tog.  It certainly does make the feet rigid boards.  I think these things are easy to see in someone new coming into a sliding sport or even a change in surface. They are harder to see in the  upper intermediate and expert skier as they won't appear as whole body movements, they will potentially just screw up the muscle tone/tightness levels making their desired movement more difficult and to slow, to slow=balance problem.  I think they aren't necessarily over riding the system, problem is they have a conscious process that has been contextualized, they have no bodily experience yet in the specific context of the trail you choose, change the context and because they don't have the control loops designed they have to rely on less precise movements.

 

Using the ice example, you don't get better at going across it by tightening up, you have to actually soften the legs, very counter intuitive for  lower motor control.  How to speed up re writing and re hardwiring people's motor program is my question I suppose.

 

thanks for the thoughts 

post #66 of 84
Quote:
Originally Posted by Tog View Post


Don't know about the plantar flexing but they definitely throw arms back and lean back. Pretty much like when slipping on ice while walking.
I always show people the emergency position. Grab your knees and if you can't turn out of it then bail to side. Adults resist the knee grabbing or holding even while just moving along. Sometimes I'll tell them to touch their knees and the hands go to the thighs. And that after we've been through it not moving.

I think there may be something to people not "having their feet" - they slip so the ground reference is off This throws the whole system off as people over ride the balance system with panic. Their reactions are 10x what is needed and just creates more problems.
I have no study evidence to back that up, just observation.
Honestly, if we could somehow dial down most peoples reactions with substances yet keep the coordination, they'd learn much quicker.

Ideally, initial learning would take place in a gently sloping flat single fall line slope with a rise at the end so they will stop. I'd have people just go straight and get used to gliding. Do that for 1/2 hour to an hour. Longer for some. That way they'd shut down a lot of the panic response. .

 

 

I had lady like this yesterday arms waving leaning into the turn. would also way try to turn by twisting her upper body and leaning it in.

 

solution I told her foot movement demoed them from her while standing still, and her try them while standing still. then I had her try while in gliding wedge with no demo from me and without her knowing which way it was going to turn her. Guide and discovery turning. worked like charm with out knowing which way to throw her body she just did the movements and ended up turning.

post #67 of 84
Quote:
Originally Posted by Josh Matta View Post
 
Quote:
Originally Posted by Tog View Post


Don't know about the plantar flexing but they definitely throw arms back and lean back. Pretty much like when slipping on ice while walking.
I always show people the emergency position. Grab your knees and if you can't turn out of it then bail to side. Adults resist the knee grabbing or holding even while just moving along. Sometimes I'll tell them to touch their knees and the hands go to the thighs. And that after we've been through it not moving.

I think there may be something to people not "having their feet" - they slip so the ground reference is off This throws the whole system off as people over ride the balance system with panic. Their reactions are 10x what is needed and just creates more problems.
I have no study evidence to back that up, just observation.
Honestly, if we could somehow dial down most peoples reactions with substances yet keep the coordination, they'd learn much quicker.

Ideally, initial learning would take place in a gently sloping flat single fall line slope with a rise at the end so they will stop. I'd have people just go straight and get used to gliding. Do that for 1/2 hour to an hour. Longer for some. That way they'd shut down a lot of the panic response. .

 

 

I had lady like this yesterday arms waving leaning into the turn. would also way try to turn by twisting her upper body and leaning it in.

 

solution I told her foot movement demoed them from her while standing still, and her try them while standing still. then I had her try while in gliding wedge with no demo from me and without her knowing which way it was going to turn her. Guide and discovery turning. worked like charm with out knowing which way to throw her body she just did the movements and ended up turning.

I'm gonna try that next time I get a flailer.  Great teaching tactic.  

The other big issue with flailers is too-big boots.  Sunday I had a guy who wears 11 size street shoes, in a 12 boot.  He rented the boots from a shop 20 minutes drive away, so couldn't go change.  

The flailing did not stop.  At the end he certainly knew why he needed to go back and get smaller boots for the next day.  I skied him down with me backwards, then gave him a plan for day #2. 

post #68 of 84
Thread Starter 

nice Josh.

 

really demonstrates the importance of breaking the general, whole body control.  Question for me then is what/where do you as instructors go when the skier demonstrates good foot/ankle control.  I know is all relative, but refining the movement happens every time we go out, are there cues beyond extremity awareness?  Leaving the body response to automaticadjustment  is fine, I only wonder if there could be cues that would expidite even this.

post #69 of 84

What do you think of JF Beaulieu's osteopath's advice about core and breathing, He seems to think this has taken his skiing to another level.  Most people only think of the deep abdominals and forget the other 3 components of the core.  He talks about the pelvic floor and the diaphragm here.  My friend did some breathing stuff with me whilst training, it was quite strange and unfamiliar but I thought it had value and worth further exploring breathing.  What do you think, as I'm sure you know the top of the core is our diaphragm!

 

post #70 of 84

I completely agree.  If people laugh at you for this then just ski away.

 

BTW - if your abs aren't sore below your belly button after skiing well then you probably can ski even better. 

post #71 of 84
Thread Starter 

great to hear such things are being recognized.  these are precisely some of the things I am wondering about.  What JFB describes in his movement you can feel in a pelvic tilt exercise, you can play with your inhalation and exhalation during the alternation of the movement and feel which is more natural for yourself.  Most will have improved mobility and muscle power with the sequence he describes in his skiing. The antagonist pattern of inhale with tilt down and exhale with tilt up will change the mobility of the spine.

 

Personally, I think it can be even more specific, the breath coordination he is using is still relying on the change in the mechanics in the turn sequence. looking at the speed of his turns I can't imagine he is breathing at that high of a rhythm, so the coordination of the diaphragm can be even more amplified for our control and on the other side of the coin, the more control the less interference we will have with trunk and pelvic control.

 

Ultimately, we should/can have the sensory ability to use the diaphragm muscle and the pelvic floor (top and bottom of the core jth :) ) completely removed from certain patterns of pelvic control. A skier could save energy and maximize power with this. you can feel it once you know how.

 

 

thanks jth - this needed more practicality and less theory.

post #72 of 84
Thread Starter 

 Some interesting film angles from 1:36-1:48

 

http://www.youtube.com/watch?v=2FgbGFBiR1I

 

 

Obviously some beautiful lower body control, but also some significant spinal mobility in these turns at that speed. Spinal engine is contingent on the combination of movement in 2 planes.

 You can see at the moment the legs reciprocate the extension in his lower back, followed by the spinal flexion through the transition, very fast pelvic tilt essentially. check for sagittal plane.

 Look for the amount of side bend/lateral flexion,  the lengthening of the inside rib basket, the compression of the outside ribs show dynamic mobility for the second plane. check for frontal plane.

 

so, the lumbar extension/flexion in combo with the thoracic lateral flexion are what generate the spine's axial torsion in SET. A skier unable to get access to these two planes of movement will not have the full capacity of the spine and the elastic energy we generate in the lengthening of the associated tissues. Throw in a body busy trying to maintain balance, unable to coordinate reflexive responses, inability to disassociate the diaphragm, etc and the access the potential energy afforded via spinal axial rotation is lost, the legs/arms have to make up the difference.

post #73 of 84

We had a number of white out powder days early this year and I am posting a link of Bridger's video of the day on Dec. 21st. I am on there for only a few seconds starting at 20 seconds (green jacket, black helmet), and at this time we had about 12" of fresh, and it was coming down at the rate of several inches per hour. It does show a stable flexible core, which I am relying on because it's white out and I can't see what's coming and the bumps underneath are disguised. This is a 30+ degree slope and I am totally skiing from my core, using my feet as feelers and my legs as shock absorbers. There are many other skiers on this video so there is some opportunity to compare core functionality. Chad, I'm appreciative of your perspective on this subject.

 

http://bridgerbowl.com/media/daily_archive/2013-12/584

post #74 of 84
Quote:
Originally Posted by RicB View Post
 

We had a number of white out powder days early this year and I am posting a link of Bridger's video of the day on Dec. 21st. I am on there for only a few seconds starting at 20 seconds (green jacket, black helmet), and at this time we had about 12" of fresh, and it was coming down at the rate of several inches per hour. It does show a stable flexible core, which I am relying on because it's white out and I can't see what's coming and the bumps underneath are disguised. This is a 30+ degree slope and I am totally skiing from my core, using my feet as feelers and my legs as shock absorbers. There are many other skiers on this video so there is some opportunity to compare core functionality. Chad, I'm appreciative of your perspective on this subject.

 

http://bridgerbowl.com/media/daily_archive/2013-12/584

Nice turns. Can definitely see it. Especially versus the full body rotators.

How does one train that though?

 

With Balance drills like these shown on Felix Neureuther's, (GER) slalom, website?

It's in German. They start at about 35secs. They also do things with the feet while juggling balls with the hands.

 

http://vimeo.com/31687063                              http://www.felix-neureuther.de/

post #75 of 84
Thread Starter 

nice video Ric, full on sensory skiing :)

 

 

Tog, there is portion of that video that I think has a lot of applicability, well all of it does, but especially the slack line work. Anyone who has ever had to stand on one knows how relaxed you have to try and keep the foot/ankle, the stiffer it is the more wobble, similar issues on a downhill skateboard with speed wobbles. They aren't perfect translations to standing on a ski, but the premise that the torso control can provide for efficient use of the legs is still applicable IMO.  Back to your conditions Ric, I think what you describe is why so many become powder hounds, the 3D aspect to the glide allows for more relaxation in the ankle/foot, there is a less precise fine tune needed to guide the skis, it really accentuates the role the more proximal pieces play. It was cool to see all the different ways the people in your vid found their own organization, some look more relaxing than others, that will afford better balance dynamics and lower body control, as you could feel.

 

Tog- training balance is fun, I do every day with people. I think if people could feel  where they colud shift their control back and forth from the torso/foot/torso/foot it makes the lessons even deeper.  Part of that torso control is first having the mobility and the coordination to use the mobility, the spine control is no different that training hip ROM of ankle ROM/control.  The funny part is the control of our trunk is one of the first things to develop, and after we rarely go back and address its restrictions and dysfunctions we develop through our lives.

 

reading other threads here it seems almost impossible, but could it be that some believe the spine really shouldn't move?  I think your video Ric showed the effects of that quite well.  How could it be the sense of effortlessness we  get in running, walking, rolling, jumping, etc all require dynamic spinal mobility and coordination, yet that isn't applicable to skiing?  Are things really so automatic, JFB found out they were not, imagine what the rest of us could find.

post #76 of 84
Thread Starter 

another look at how hip and pelvic motion on one side effect the upper body on the other side.

 

http://thegaitguys.tumblr.com/post/13869907052/arm-swing-in-gait-and-running-part-1-there-is

 

To save anyone from actually reading the article, I thought this was especially relative to skiing mechanics...

 

" Internal hip rotation is a precursor to hip extension. In other words, the hip must pass through the internal rotation phase before it starts into hip extension. This means that the opposite shoulder must do the same thing. Go ahead, get up and walk and you will note it yourself. But what you must realize is that if shoulder internal rotation range is lost or limited then the posterior sling will be insufficient and hip extension cannot be achieved as effectively. It works both ways gang ! Remember, it is not only a mechanical phenomenon, it is a centrally mediated neurological phenomenon as well."

 

Looking at stills of skiers this is apparent, the more neutral the spine the more neutral the shoulder and hip, the more spinal mobility/counter rotation in the segments the more the rotation of both hip and shoulder joints follow.  I think the prereq of the hip internal rotation to engage the extensors also supports the importance of the foot/ankle control issues. The article makes the implication that issues in the upper portion of these synergies will have as much influence  as from the bottom up.

 

jth mentioned sling function, I am sure it has appeared here before, but anyone could look at anterior and posterior sling components. The coordination to create the  contralateral movement is a definition of more efficient movement, the upper and lower body are not working independently of each other, the seperation and counter rotation is inherent to maximize speed and control of movement.


Edited by chad - 1/23/14 at 7:45pm
post #77 of 84

Chad, did you ever do any courses or read anythings from Thomas Myers on anatomy trains?  Interesting stuff, he's presenting nearby and I'm considering going to see him and learn more about motion and fascia.

post #78 of 84
Thread Starter 

His book, anatomy trains is one of my references and i read it often.  I am still a couple years away from attending his trainings, pretty consumed with feldenkrais training right now.  I have studied fascial work through john barnes ideology, it was getting a little off track in my mind and like the structural integration/ida rolf philosophy better. If you want to begin some background reading I would highly recommend the work being done by Robert Schleip out of Germany and the Stecco family in Italy. The past decade has been tremendous for better understanding the role connective tissue has in our movement.

post #79 of 84

Interesting stuff. Chad the key is to promote movements or activities people can do.

 

Here's something you might like. Shot at 300 frames/sec. Slo mo of Felix Neureuther skiing slalom at Kitzbuhel a few years ago. He won the race. Interesting side fact- his mom is Rossi Mittermaier, multiple Olympic gold medalist in skiing, and his dad skied slalom on the World Cup.

 

You can see the tremendous upper body stability. He was the one on the slack line video above.

 

http://youtu.be/Fe4sW5yfJHk

 

Just to give you an idea of how much the above video was slowed down, here's Felix in the same race in full speed. Not sure if it's the exact same run, but it's the same race.

 


Edited by Tog - 1/29/14 at 6:07am
post #80 of 84
Thread Starter 

thanks tog, haven't watched those before, those guys and gals are incredible to watch move, just follow the separation from the upper part of the thoracic spine compared to the positioning of the pelvis  through those vids, not to take away the dynamic control of the hips and legs, but damn, how can anyone not appreciate the dynamic stability they have and what it does for setting the placement of the feet/legs. 

 

been reading some stuff about rhythmic movement training and the  role of reflex integration, a blurp from it I thought was particularly relative and also more clearly answers JASP's suggestion, thinking about developing skiers, here is the flow of infant development...

 

1. breathing- the foundation of movement pattern development

2. mouthing- particularly grasp control (ok, maybe that is not so relevant to skiing)

3. naval radiation- also termed core-distal connectivity, development of the sense of our own center before we use the extremities

4. upper-lower connectivity- development of the sense of how the upper and lower halves effect one another to achieve stability

5. body half connectivity- sense development of the left and right halves of the body, allows for mobility in all directions

6. cross lateral connectivity- all the above patterns need to be integrated well to allow this final stage, sense and development of of the opposite arm and leg to maximize efficient movement.

 

with respect to skiing, changes in context on the hill, conditions, terrain, fatigue, etc we are constantly cycling up and down, poor use of of patterns higher on the list will make using the more complex patterns difficult, pretty common sense I suppose, but instruction beyond attention to feet even in the midst of developing that skill may enhance the learning of the skier.

post #81 of 84

I'm sure the guys that are at the top of their game will have fitness coaches that will work on movement on multiple plane on top of their skiing skills.  Obviously these movement specialist are not used by most instructors. 

post #82 of 84

This Bode video has some of his unusual excercises he does.

Quote:
Originally Posted by sibhusky View Post

Another interesting one.
post #83 of 84
Thread Starter 

a couple thoughts to add, Mr. Cook has a great discussion on his joint by joint approach to movement, in relation to skiing, when the lower body is engaged at the moment of highest compression or when at the stage of the turn where they are relatively unweighted, how would this application change in the skier, do you think it even changes?.  It also has a nice description of the importance of the foot sensory abilities.

 

In addition, from his book, "The skeleton is supported against gravity through movement by the constant and coordinated work of stabilizing movers.  These small , deeper muscles enhance the efficiency and power of the prime movers by creating resistance, stability and support of movement at one movable segment, and allowing freedom of movement at another This interaction happens in milliseconds and occurs without conscious control."   Knowing that movement is context dependent and the roles of a muscle can shift from a prime mover to a stabilizer, I wonder what some of your thoughts on how these roles shift in the body in the various stages of ski movement.

 

http://graycook.com/?p=35

 

included this link, has a nice description of the role of the legs in spinal engine theory

 

http://www.bsmpg.com/Portals/52884/docs/Morgan.2012.pdf

post #84 of 84
Thread Starter 

a few provoking thoughts relative to efficient management of our bodies I thought applied well to skiing

 

http://www.bettermovement.org/2010/three-essential-elements-of-good-posture/

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