The holy Grail

PMTS Forum

The holy Grail

Postby skier_j » Wed Oct 13, 2004 5:39 pm

One of the things that is consistently ignored or argued incessantly among ski fanatics of all ilks is that which is not part of the methods used in whatever ilk you happen to subscribe to.

I'd like to throw out a premise and see where it takes us , if I may.

My brief CV is: skier for almost 40 years, next to no formal lessons, Snowboarder starting at 40 something with the help of a generous AASI level II instructor. In 40 years I have had maybe 15 days of formal ski instruction and maybe that many days of snowboard instruction as well.

One last item is I am a member of NSP for the past 15 years, currently a division level officer in that organization.

I have always followed the best skiers I could find---wherever I happen to be at the time--- and tried to emulate what they did that worked. I try not to get mixed up in definitional debates.

However, there seems to be, on this site, a complete a complete dismissal of two terms, and the resultant skiing tools that give rise to those terms, that have an origin in PSIA terminology, this distresses me greatly.

I have mentioned to one member here in private messages that to summarily dismiss them is (in my mind) to hope that you never get injured on the hill and require the services of a patrol sled pilot.

Right, wrong or indifferent---I have never come across a sled pilot that did not use a wedge and rotary movements EVERY time they drive a loaded sled.

As many have said, the more tools you have at your disposal, the better you will ultimatly be as a skier.

My query is why are these movements so despised within this PMTS community?

Harald---I'd love to here your view on this, admittedly, very narrow view.

I'll add that in NSP I have heard it said, with more and more frequency these days, that we have to train our newest members the effective use of these movements because more and more frequently, the population of new NSP members have no background (either PSIA or PMTS) to perform these movements.

Why? DTP methodology thats why.

With PSIA you can at least get an instructor to help teach these skills.


Thanks in advance

Jeff
Whee!
skier_j
 
Posts: 33
Joined: Thu Jun 24, 2004 6:00 am

wedge and rotary

Postby Rusty Guy » Wed Oct 13, 2004 8:00 pm

I think I will surprise all with one point.

Keep in mind, negotiating a sled down any pitch, is often primarily a defensive endeavor. It's an "I don't want to go there type of skiing". That may be the reason for inherently defensive skiing such as a wedge.

I also want to toss out an idea that I hope is not glossed over. There is a difference between a "snowplow" and what is termed a gliding wedge. It is different functionally and different interms of where it leads teaching.

Knowing your background, perhaps you can help me get this point across. Tipping a ski on edge, whether it is a tiny amount of edging or the type evidenced in a WC turn involves "rotary" biomechanics. This seems to set people off. By this I mean the tib/fib rotates, the femur rotates in the hip, even the mere inversion/eversion of the foot involves lateral or medial rotation due to the complexity of a tri-planar joint system. All the rotary movement that I reference may translate into merely tipping the ski on edge with no rotation of the ski. I'm differentiating between roary movement and rotation of the ski or pivoting.

It's another sermon to suggest WC slalom racers don't redirect/pivot/turn their skis, as a tool, if needed.

By the way, every skier owes a tremendous debt of gratitude to every patroller regardless of having ever needed assistance. It can be a wonderful job and at times miserable.

FYI I pro patrolled for years prior to teaching full time
Rusty Guy
 

Hopefully Harald will answer you

Postby John Mason » Wed Oct 13, 2004 8:55 pm

I don't see a contradiction. Rusty's distinction is quite good. A braking snowplow is taught in PMTS (and it doesn't take long to teach) and is in HH's book as a LMD or line manauvering device. The vast majority of skiers that come to HH already have this skill (as should be no surprise as it's the normal first lesson).

It just as a student wanting to learn to ski, like you, your want to ski like whatever your perception of the best skier on the hill is. I can tell you, I have never wanted or looked forward to learning to ski with an extreme snowplow required to take some 230 lb athlete with a blown knee off a double black like the ski patrol had to do with my son last summer.

That looks like WORK not fun. I'm sure it's rewarding work. I have the utmost respect for the ski patrollers out there.

PMTS just doesn't happen to focus on the wedge as a learning tool or progression for PMTS's stated reasons. It doesn't mean never ever wedge.

Likewise, a ski patroller, I would think would not want to ski with a super grippy super stiff great carving ski, because these are more difficult to modulate a snowplow in. I would think they would find a softer ski that lets the snowplow be modulated easier would be better.

PMTS movement patterns still can change the direction of the snowplough though. The traditional bad snowplough that everyone seems to agree not to teach, press the big toe on the grape while twisting that outside ski in the direction of the turn can be flipped a bit. A snowplow will still turn by a lightening and tipping of the inside ski rather than focus on pivoting the outside ski.

Basically what you're bringing up is a totally different skiing situation. It might as well be like saying PMTS is weak because you can't learn cross country skiing from it.

The discussion of how many ways a phantom move generated turn and it's resultant rotary (as rusty pointed out) can be combined with different edge angles to create different turns is another discussion. Rotary exists in PMTS. But it's more of a result than a "pivoted input".

The two footed release that beginners are started in, the phantom move with flat skis create a very shmeared turn. It's certainly not what most people would think of as a carved turn. You can revert to this turn whenever. If your not able to carve steeps, two footed release works fine if you find yourself in over your head. It's also a nice fall back turn where you just want a different style down the hill.

But, you have brought up a totally true point. A accomplished PMTS skier that has all the versitality of a skier like Eric Deslauriers in his All Mountain book (which also doesn't teach or cover the snowplough), is going to need some serious help and practice dealing with a heavy sled with a person in it on a steep slope.

You guys are the true "firefighters" of the slopes. I salute you. My son salutes you.
John Mason
 
Posts: 1050
Joined: Wed Feb 18, 2004 10:52 pm
Location: Lafayette, Indiana, USA

Postby Rusty Guy » Thu Oct 14, 2004 6:01 am

Probably a great way to teach folks to "release" their skis would be to have them perform a falling leaf with 300 lbs in a sled. You cannot rotate your upper body because you have a death grip on the handles. The movements all have to begin in the sub talor and must be exceedingly subtle. As I harken back the upper body isn't going to move much either. It's going to remain fairly static. Other tan a little inversion/eversion there would be subtle fore/aft adjustments to create the falling leaf effect.

You mentioned training. I pro patrolled in Canada while living there. We had a wonderful arrangement with the local ski school where we joined them in clinics. I have instituted a similar arrangement here in the US where I work. One minor issue is the bulk of our patroller are on AT or teli gear.

Most just keep their heel down when they clinic.
Rusty Guy
 

Postby SkierSynergy » Thu Oct 14, 2004 5:28 pm

Most of this has been said over and over, but I'll try to say it again in a slightly different framework.

In PMTS there are a few basic principles that guide decisions related to technique and if something violates one of these principles, in PMTS, don?t do it. You can see these principles woven into the books. They are presented more obviously in the instructor?s manual though I don?t think they are all in one place as principles. However, if you do any instructor?s training at a PMTS Cert workshop they are presented as basic principles.

1.Development of dynamic balance (as opposed to stability) is most important.

2. Use movements that allow fine motor control.

3. Use only the most efficient movements that most take advantage of the skis' design.

4. In learning, use only movements that don?t have to be unlearned.

There are maybe one or two more that can be added, but these are good enough for now.

So now consider steering and rotary motions in light of these principles.

1. Development of dynamic balance (as opposed to stability) is most important. Use/develop movements that aid dynamic balance. These are movements that occur as low in the kinetic chain as possible and do not have negative consequences on balance later in the turn. Eversion/inversion/dorsiflexion/plantar flexion are primary here. Leg flexion is higher up the chain, but it aids in the foot movements by freeing up more range of motion. It is also key in adjusting transfer of weight from one foot to the other, and in itself has few negative consequences later in the turn (this could be thought of as an efficiency principle). Rotary movements are negative on both accounts. They originate higher in the kinetic chain and they have dramatic consequences that have to be tightly controlled and finely adjusted through the turn in order to balance properly. So in terms of balance, rotary movements are not preferred.

2. Use movements that allow fine motor control. Again, movements in the foot and ankle are primary here. They allow the finest motor control. Leg flexion is next in line. However, because they originate in such large and unbalanced sets of muscles, rotary movements have very poor fine motor control ? it gets worse the more dynamic the situation. It gets even more difficult if you are trying to finely ?blend? it with other movements. The ?unwanted later consequences corollary? also applies here. Once rotation is started it has to be eliminated by the end of the turn or it gets very difficult to release properly. Further, if steering and rotation are used, they have to be reversed for the next turn. So, the skier must eliminates the rotation by countering it (doing steering and rotary movements in the opposite direction), but now we have to not only finely adjust and control the initial movements, but finely adjust and control the counteraction. It?s like trying to control a constantly changing reverberation of negative effects with a tool that doesn?t offer fine enough control. If anyone can do all this, hats off to them, but it seems simpler to not start the whole cycle in the first place ? especially when, you don?t need to (except for very special circumstances and then you have to live with the tradeoffs). If you analyze the movements of anyone who uses steering and rotary movements it is a constant, tensioned athletic fight with these issues. Also, physiologically, it ends up being much easier to initiate rotation into the system -- this also makes it harder to control. Therefore, it?s better to concentrate on the movements/skills that prohibit and restrain it. If you teach it and try to use steering and rotary motions as desirable skills, you?ll never get rid of them when you most need to. I grew up learning traditional ski teaching methods and only learned PMTS movements in the last several years. Only just recently have I really felt like I have consolidated the right movements. I know because during non-thinking emergency maneuvers ? like a hole suddenly coming up or someone suddenly being in the way I no longer get on the big toe edge right away and stem and rotate. Instead, I go hard to the little toe edge and flex the inside leg hard. One thing that really helped consolidate these movements into muscle memory was using the Harb Carvers. If you do try to steer or have any hip or upper body rotation into the turn with the Carvers, they start to skid and that gets scary. On Harb Carvers, Primary movements are the only ones that will work well, so very quickly you learn to do it right.

3. Use only the most efficient movements that most take advantage of the skis' design. I think I said enough on efficiency already. However, I might add that this is an important point for those of us who are getting a little older. I regularly get out skiing with competitive skiers in their early 20s and get less tired than they do (I find this is especially true in the bumps). I know this is a direct result of learning PMTS technique. I have also seen this really improve my AT skiing. Once you put a good size pack on and ski, any extraneous or negative movements become amplified and are really hard to deal with.

4. In learning, use only movements that don?t have to be unlearned. If high level parallel skiing is the goal, then develop those movements right from the start. The rotary-stem connection is very strong. They reinforce each other and the reinforcement gets stronger the steeper the terrain gets. So, if you want parallel skiing with efficient releases and dynamic balance, why not start working on those skills right from the get-go rather than developing exactly the opposite of what you need at expert levels your whole beginner and intermediate career.

Rusty,

I have skied with a mountaineering pack sled before and you are absolutely right about the necessity of proper release skills with a sled on the steeps.
SkierSynergy.com -- comprehensive services for the girlfriends of skiers
SkierSynergy
 
Posts: 305
Joined: Tue Jul 20, 2004 11:05 am
Location: Mt. Hood -- Portland Oregon

Postby milesb » Fri Oct 15, 2004 10:48 am

Skier Synergy, that was very informative. I have a question about accuracy. Pointing with the feet is nowhere near as accurate as pointing with the hands (due to the large vs fine motor control), however, I have done some simple exercises that have made this action much more accurate. The question is, can indirectly controlling direction by indirectly tipping the stance ski using the free foot ever be as accurate as merely pointing the feet? I was planning on working on this this coming season, is it worth it?
Also, you said If anyone can do all this, hats off to them, but it seems simpler to not start the whole cycle in the first place ? especially when, you don?t need to (except for very special circumstances and then you have to live with the tradeoffs).
What are the special circumstances you have in mind?
YouTube channel https://www.youtube.com/channel/UCH78E6wIKnq3Fg0eUf2MFng
User avatar
milesb
 
Posts: 981
Joined: Sat Feb 21, 2004 10:17 am
Location: Los Angeles

Postby Harald » Fri Oct 15, 2004 11:10 am

As Ski Syn remarked, the PMTS principles are outlined throughout the first and second ?Anyone can be an Expert Skier?, books and also in the PMTS Instructor Manual. It is always good to hear someone else?s application of them especially from skiers like SS, as he has interpreted PMTS for his own use. If skiers of his ability can in such a short time internalize and utilize the system successfully it speaks to its effectiveness and friendliness. People like SS also help evolve and refine PMTS. PMTS is holding up favorably in all skiing situations with the basic principles still solid. We have added to and adjusted them slightly, but almost unnoticeably, as there has been little need to change the original concepts.
An old Navajo proverb,"Tradition is the ememy of progress." We never want to becometraditional.

PMTS has a number of very bright people to thank for helping refine the logic and definitions during the development years. My contribution was the mechanical structuring of the progression and technique, but many suggestions and refinements came from such people as Bob Hintermeister, Kim Peterson, Rich Messer, Mel Brown and of course Diana Rogers.

What more could you possibly ask for, an extraordinarily talented group. I am so proud of the fact that PMTS has attracted such energetic bright and devoted skiers. I can?t list them all here but Ski Syn is a new contributor, one of the many. Here on this short list we have three doctors of education, one of biomechanics and a Master Engineer. In the early NASA years, they had the brightest and the finest, that's how I feel working with the people I work with in PMTS.

Diana is not just an engineer; she is a brilliant engineer and a brilliant skier (she used to work for a division of NASA). She can interpret dynamics and physics into skiing and vice versa. I have never met anyone who could interpret the fundamental concepts and movements of skiing and apply them to the laws of physics the way she can. I have worked and discussed skiing with others who are educated at her level, others who have written about skiing in technical terms, Juris Vagners, PhD. and John Howe for example. Diana can not only make skiing simpler to understand, but she can also ski at the highest levels.

I first met Ski Syn when he attended our Kicking Horse All Mountain Camp. He was easily recognized as an excellent skier and had no problem skiing anywhere. He could have passed any PSIA full cert course in the country at that time. He was not satisfied with his skiing yet. This demonstrates his passion for knowledge and a burning desire to improve. Ski Syn vowed to improve and I gave him a list of technical areas to work on. He worked and he accomplished. He is still improving, yet he is already one of the finest skiers on any mountain. Diana is the same way, she is a great skier, but not a complacent skier, and she strives to be better every time she skis. She is getting better even though she is already at a very high level, a level that it takes National Ski Team skiers to out ski her. She continues to gain ground every season on younger racers, who are training full time at ski academies.

PMTS Direct Parallel is not only a Direct Parallel system for beginning skiers, it encompasses coaching techniques for skiers at the highest level, including racers working toward the World Cup level. In that process of course we include our boot alignment and foot bed construction knowledge. No matter what level of skier you are, PMTS movement techniques can elevate your skiing rapidly. We have the coaches who can coach the coaches. We have the coaches who can coach the best racers. We have the coaches that can improve the beginners or motivated recreational skiers.

Mel Brown has been an examiner in PSIA her who life, the youngest PSIA examiner ever, she coaches high school racers now and she uses PMTS methods. Mel has developed young racers the last two years and brought them to the US National Development Team level and she attributes her success to PMTS techniques. We know Mel is a great coach, but she still attributes her success to PMTS.

Again, I?m not saying there aren?t other ways to learn skiing, but if you want to understand what you are trying to accomplish, have a plan and realistic goals and you want to get it done fast, you won?t be disappointed. I can suggest if you do want to take a different road, book early, because all of our coaches and camps are in high demand and often booked months in advance.
Harald
 

Postby Guest » Sun Oct 17, 2004 12:18 pm

One thing I said almost as an afterthought in the original post was that possibly setting I described was admittedly a very narrow application.

Rusty's defining these techniques in this context as "defensive skiing" is exactly right---I had not given sufficient thought to that point. To expand on that point however--- How would I reposition my sled at the end of a traverse to point in the opposite direction---and keep things under sufficient control---without a very strong rotary move?

While I agree that a braking wedge is something we can all ski without---except in narrow situations such as I have described---rotary movements to me are not so limited or limiting.

One final thought on equipment. I buy skis for everyday skiing and if I wanted a 6 star or slalom ski as my everyday ski, I could use them to bring a sled down the hill. No doubt some ski's are better suited than others, just as ultra wide powder skis make those conditions easier, It is all in what you get used to and have available. It really boils down to the pilot, not the tools.

Thanks

Jeff
Guest
 

Postby ydnar » Tue Oct 19, 2004 12:17 am

Skier Synergy,

Rotary movements do not have to originate higher up the kenitic chain than tipping movements. Just as I can feel myself tip the foot inside my boot and have that action work through the kenitic chain to tip my skis on edge I can also feel myself pointing where I want to go with my foot and through the actions of the kenitic chain have my skis take me there. In fact I often find that the pointing feel produces finer control to go just where I want to go.

yd
ydnar
 

Postby piggyslayer » Tue Oct 19, 2004 6:46 am

Ydnar, all,
Just my comment: the concept of "pointing" has been discussed on this forum last year. It was introduced by Mechanic and you can find the discussion, for example, in the "How does PMTS generate rotary turns like at the top of Mogul" thread:
http://www.realskiers.com/pmtsforum/viewtopic.php?t=165&start=0&postdays=0&postorder=asc&highlight=

In a nutshell, PMTS-ians did not like the idea. Harald has confirmed the importance of striving to eliminate any rotary input placed on the skis.
Piggy Slayer
let the piggy breathe
piggyslayer
 
Posts: 320
Joined: Tue Nov 04, 2003 9:27 pm
Location: New Jersey

fine motor control and the origin of rotation

Postby SkierSynergy » Tue Oct 19, 2004 4:13 pm

I thought I'd answer a couple of questions from previous posts

Milesb,

Actually the foot has very fine motor control -- only second to the hand. Many primates use their feet with great dexterity and people who have to adapt and use their feet as hands can do amazing things with them -- including write and paint.

I think a big problem is that people buy boots (either in design or fit) that restrict/prohibit the amount of fine control that is available.

ydnar wrote:Rotary movements do not have to originate higher up the kenitic chain than tipping movements. Just as I can feel myself tip the foot inside my boot and have that action work through the kenitic chain to tip my skis on edge I can also feel myself pointing where I want to go with my foot and through the actions of the kenitic chain have my skis take me there. In fact I often find that the pointing feel produces finer control to go just where I want to go.



The main issue here is which joints and sets of muscles produce the effect of being able to point (i.e., rotate) the foot.

By themselves, the foot and ankle have very limited ability to unidimensionally rotate (Abduct/induct) the foot. One joint in the ankle only offers plantar/dorsiflexion flexion. The other joint moves the foot in all three directions of movement at once. and is related to a person?s tendencies to pronate and/or supinate when the foot is weighted or un-weighted.

Rotation that originates in the foot/ankle is

1) not produced in isolation ? it is produced along with eversion/inversion of the heel and plantar/dorsiflexion

2) is of little consequence to turning the skis ? especially in comparison with the tipping movements that are produced at the same time and

3) are actually in opposition to the turning direction of the skis when the pronation and supination occurs: during supination when the heel is inverted to press the ankle to the outside of the boot and produce a turn in that direction, the foot actually adducts (turns inward); during pronation when the heel everts and puts pressure on the inside edge, the foot tends to abduct (turn outward). In either case the pressuring and the rotation are in opposite directions.

So, if active rotation doesn't come from that low in the kinetic chain where does it originate. The knee/lower leg and the hip/upper leg. Grab your knee with one hand and your ankle with the other. If you try to rotate the foot while not moving the knee and keeping the foot flat, you will feel the muscles in your leg start to activate. There is a limited amount of rotation available in the lower leg alone and quite a bit more available by adding joints and muscles in the upper leg and hip. However, there are numerous negative consequences and difficulties related to these movements ? especially when one tries to combine them with wider stance widths. Some of the skiing related issues have already been outlined above, and in numerous threads such as ?Not holding back on rotary skills teaching?:
http://www.realskiers.com/pmtsforum/viewtopic.php?t=180&highlight=teaching+rotary

A search of the forum using these terms pulls up a lot of stuff.

The negative long term health and injury related issues started in a post by me in
http://www.realskiers.com/pmtsforum/viewtopic.php?t=228

SkierSynergy wrote:One good researcher on issues of stance width is Tom Andriacchi from Stanford University. He is one of the top researchers on knee injuries and does a lot of work with these issues in bike racing. It turns out that the relationship between flexion, stance width, and lower leg rotation are really important for injury issues in bikers.

More recently he gave a presentation in the Biomechanics section of the International Congress of the International Society of Ski Safety 2003. His analysis of knee mechanics in deep flexion during skiing have some interesting conclusions. the following are my interpretations of his stuff.

1. Andriacchi's data on deep flexion concludes that lower leg rotation is to some extent inherent in the action of flexing the knees. When the knees are flexed the tibia naturally rotates a bit. the extent increases with the deepness of the flex (just how much also varies among individuals). In a stance no wider than the hips, the affects are minimal. However, the effects increase dramatically as the stance widens or moves into a wedge. Flexion with either a wide stance or wedge greatly increases the rotational force while also putting most of the force on the tail of the ski.

I read this as an inevitable recipe for skidding at some point in the turn - probably the end. In order to reduce these effects, Andriacchi suggests a narrower stance with emphasis on little toe edge tipping. As far as I know he is not familiar with PMTS.

2. More importantly, his work also concludes that either a wide stance or a wedge with flexion dramatically increases stress on the ACL. Again, a narrower stance with emphasis on little toe edge tipping generally reduces stress on the knee. In addition, contracting the leg muscles to pull the leg back also reduces the stress on the ACL by reducing anterior translation of the tibia (stabalizing the head of the tibia in it's more natural position).

Considering that knee injuries of various types account for approximately 30-40% of all alpine ski injuries ? and that there are probably even more complaints about sore or tired knees (especially from older skiers) one should take this advice seriously.

On this research, the traditional advice of a horizontally wide stance with flexing and inward driving of the knee is the worst thing you could do for either edge hold or knee stress; and an move toward a horizontally narrower stance with emphasis on little toe edge tipping enhances both carving hold and reduction of knee stress.

You can also see Dr Mike Langran's summary of the Congress at:

http://www.ski-injury.com/lrn.htm#Biomechanics

I don't think Andriacchi has published the ski paper in any journal, though he is at Stanford. I have several of his other papers dealing with these issues in bike racers. I will look for them. Originally I think I got them while doing searches under his name on the Stanford website and the sites of the international Society for Biomechanics in Sports.

Hope this is interesting.

Jay


And became the following thread:

http://www.realskiers.com/pmtsforum/viewtopic.php?t=225&start=45

I think it?s fair to say that steering and rotary movements could be picked out as a prime choice for the most negative movements available to use in skiing. At the same time they are the most tempting to use psychologically and physiologically Therefore, they are the movements which are the most important to eliminate in instruction? of course they are eliminated not by addressing them directly in any negative sense, but by replacing them with more effective, efficient and healthier ways to ski .
SkierSynergy.com -- comprehensive services for the girlfriends of skiers
SkierSynergy
 
Posts: 305
Joined: Tue Jul 20, 2004 11:05 am
Location: Mt. Hood -- Portland Oregon

Answer to Piggyslayer

Postby Harald » Thu Oct 21, 2004 3:11 pm

Piggyslayer, your posts are always right on the mark. In most cases your questions and views are more enlightening, accurate and focused than instructors with years of tradition only training.

Remember they have a limited view of the world, a one sided belief system. You have the experience of participating in both worlds. You don?t follow ideology blindly, you use what works for your skiing.

I know many instructors who compromise their own skiing and teaching progress, quality and ability because of the ideology they blindly follow or are forced to follow. You can?t prove to a fundamentalist that Darwin is the way the world evolved, just as you can?t convince a Darwinist that the bible is right about how we appeared on earth. It is futile to enter into the debate.

The traditional instructor/skier (less so the skier) will tell you they are skiing well and correctly, even if their performance doesn?t stack up. Even when the skier himself, from the video thread posted here from Epic, responded by admitting that the skiing in the video was below standard, others gushed over the same turns. What does that tell you about their movement analysis model?

When you have nebulous standards and a dart board movement analysis format, it?s very difficult to measure performance. It may not be more difficult to teach skiing this way, however, because you can move your lesson all over the place and the skier never knows if they are actually making progress.

I agree the public should not have to find out they had lessons that took their skiing in the wrong direction after years of trying. Too bad it can?t be a better kept secret!!! Most of our clients exactly make that comment. They are disillusioned, often angry and definitely not going back to traditional ski instruction.

Remember it doesn?t matter how you ski, as long as you like how you ski, can talk about how you think you are skiing and that everyone around you agrees that you like the way you ski.

Unfortunately that?s not enough for a large majority of the population and definitely not enough for the perceptive skier who finds PMTS. You know what, if it wasn?t for PMTS, skiers would never know that their skiing was headed in the wrong direction.

Notice how after kinesthetic and biomechanical explanations appear, as on some of the previous posts, there are no arguments or posts to support traditional teaching or skiing. There are many backdoor exit strategies used when these people are exposed, but they may not have an exit strategy for science and research. Why it is that traditional views on skiing are not represented at the International Congress of Skiing and Science? How could they possibly respond, ?The PhDs are wrong??

Oh Yes, I forgot, that?s what they (PSIA instructors) said after the PMTS Instructor Manual came out, which has contributions and was edited by two PhDs and an engineer. But what do two PhDs and an engineer, who also happen to be PSIA certified, and PMTS accredited, know about skiing? They can?t possibly be credible! Why, because they turned to the dark side. It is beyond ridicules. I am just speechless, many are only outraged.
Harald
 

Postby ydnar » Thu Oct 21, 2004 4:57 pm

Skier Synergy,

Sorry for taking so long to respond, I'm fighting a computer in its death throes.

You point out how pointing the foot is biomechanically limited. Isn't tipping the foot also limited biomechanically? Also isn't the amount that the foot can tip further restricted by the ski boot to the point in some instances that with hard footbeds and too tight boots the tipping can be inhibited to the point that the foot can't function properly and the skier is forced to use the larger joints/muscles to accomplish tipping? This last case results in a skier with little fine control over their ski and all the problems that can result from using large muscles to try to fine tune the ski snow interaction.

I can only point so far without involving joints further up along the kenitic chain but I can only tip the foot so far without involving joints further up the kenitic chain, and isn't this the idea behind the kenitic chain. As I understand from my reading of Harald's first two books the idea was that a simple basic movement, a cue if you will, will serve to activate the kenitic chain and result in the necessary movements of the larger parts of the body without having to focus on conciously moving those large powerfull body parts with the added plus that recruitment of the large muscles in this manner means that they will be less likely to make overpowering movements. Further, correct me if I am wrong here but I seem to have gotten the idea that one of the things that free foot tipping recruits along the kenitic chain is what Harald refers to as passive rotation of the femur in the pelvic socket. Personally, I can sense no difference in the feel of this femur rotation whether it is recruited by foot pointing or by foot tipping. Either way the outcome is the femur rotating in the hip socket as a secondary effect of the basic movement.

As you point out rotation of the foot and tipping of the foot are very intricately involved with each other. When introducing tipping of the foot to students one of the things I watch for is a inward rotation of the heel as they try to tip the foot further and further. This is particularly a problem with long time skiers who has some kind of a heel push as a major part of their technique on traditional skis. The cure for this in my experience is to have the student add a little pointing of the toes in the direction of the turn as they are focusing on primarily tipping the foot. Conversly, when working on pointing the foot one has to watch for diverging of the tips of the skis, the cure here being making sure that the foot is tipped before too much effort has been put into pointing it.

You comment that when avoiding an obstacle you no longer stem and rotate in an effort to avoid it, you just tip the foot a little more and change the arc of the turn to miss the obstacle. In the same situation my trained reflex is to just point my toes to change the arc of the turn to miss the obstacle. Either way, the outcome is the same. By the way the reason that pointing is my reflexive action is becuse I'v been skiing by pointing my right foot right and left foot left for well over twelve years while tipping my foot is something that I haved only been playing with for the six or seven years since I read Harald's first book.

Sorry, I just cant't agree with your blanket statement that rotary movements are bad and must be eliminated. Rotaty actions/movements need to be understood and have to be a part of every good skiers range of skills. Just as rotary moves can be something that can create problems if missused rotary moves can be something that can aid in recovery when something else goes wrong. Even in this day and age racers sometimes need to use rotation to redirect their skis onto the line they want. True, they don't like to have to do this because it slows them down but it's better than missing the next gate.

yd
ydnar
 

Response to ydnar

Postby SkierSynergy » Thu Oct 21, 2004 6:58 pm

Edited on 10/22/ for clarity, etc.

ydnar,

Thanks for the thoughtful response. I think you have been polite in your questioning of my posts and I hope you have found my responses the same. I think the interchange will be fruitful.

Some of what you say is true and I would agree with. For example that many people choose boots and fit their boots so that many functional aspects of the ankle movement is fatally restricted. These people are forced to use movements originating higher up. A change in equipment or fit would do more than a year of lessons to improve their skiing.

The difference with tipping is that inversion/eversion activates the turning design of the ski and so a little motion will do a lot. If you rotate/steer with movements higher up the chain they will have also have big effect to redirect the ski, but then there are other negative affects and consequences that you have to live with. If you have to do this because of an error or special circumstance (getting behind in the gates, obstacles, etc.) then you do, but what one does as a result of errors and special circumstances should not form the model what skills are most effective in the rest of our skiing.

ydnar wrote:I can only point so far without involving joints further up along the kenitic chain but I can only tip the foot so far without involving joints further up the kenitic chain, and isn't this the idea behind the kenitic chain.


Actually, I was trying to say that you can not point your feet (rotate your legs) into the turn from the ankle. You must use movements that start high in the chain. Any rotation that has it's roots in the ankle (from the subtalar joint) are actually are in the wrong direction and are more of an idiosyncratic property of an individuals anatomy ( the tendency to pronate or supinate) than something that is controlled through skill. Why this is important will become clear in a bit.

Also, you are correct that other movements further up the chain help. However, active rotation is not one of them. The main issue is not whether movements higher up the chain are recruited in the tipping movements. Some movements are extremely important for facillitating the effect of tipping movemements started in the ankle. Leg flexion is a key one here. It frees up more range of external rotation of the femur so that the tipping that starts in the ankle can have a more efficient and bigger effect and it also makes plantar/dorsiflexion easier and more controlled-- the movemenst that control fore and aft movement.

[By the way, if anyone understands the topic on Epic about how pointing your toes at the start of the turn while keeping your shins pressured into your boot fronts, brings you forward (the ballerina turn). Please PM me about what movements could press your shins forward and bring you into the front seat while you are busy pointing your toes. Sorry for the digression.]

The main issue is in the causal direction of the movements. If the movements start in the ankle they can do their job with little effect on balance. If the movements originate higher up, then they tend to be larger to begin with, harder to control, and have a bigger effect on balance. There is a dramatic difference between tipping done at the ankle with the leg is flexed enough to allow the other joints higher up to rotate passively and any active rotation that must originate higher up.

If the causality is not taken into account then one will see no difference between active and passive rotation of the femur. However the difference between active and passive is everything.

In the case where the tipping is started in the ankle while the leg is flexed, both the lower leg and the femur passively rotate. The rotation of the bones is an effect of the tipping and flexion. They are not produced by rotation related muscles higher up and therefore, the rotation in the joints does not add rotational force or torque into the system as a whole. The rotation "follows" the turning effect produced by the skis. Movements like flexion and counter action help allow the "following". In active rotation the leg rotation is "leading" the skis creating a rotational effect that disturbs the entire system. It isn't that one can't deal with the added and harder to control forces. People do it every day. However, even a casual analysis of their skiing shows that it's less efficient, harder to control, more susceptible to inconsistency (and injury), tends to disturb balance, and requires more athleticism (and its probably slower in the course, though that's not my real focus) -- all when there is an easier alternative.

In descriptions such as those given by Bob Barnes active and passive rotation are seen as essentially the same. See the "Most Basic Ski Movement Patterns" thread on epic -- where he chooses independent leg steering as "the most important, basic movement pattern of contemporary skiing, the one that applies in some form in nearly every good turn." I think his writing is clear and direct, so it's interesting to take a look at.

The argument is something like "even when one tries not to steer, there is passive steering. So, don't say steering isn't desirable or necessary." To use his favorite analogy of car steering, I would say that this kind of arguement would be like not making a distinction between passive changes in toe in/out as a result of castor and camber changes and active steering input from the wheel by the driver. Each affects direction, but they are radically different in nature (I am an avid motorsports enthusiest and work on all my own cars). Now, he also has other reasons for arguing for steering which aren't relevant here, so please don't respond saying I'm over-simplifying his position. If you throw both types of rotation into the same basket, I think this results in a vague and imprecise use of the term and fails to recognize the most important thing about the distinction. In another thread, Am I the only one ... ) he celebrates the vagueness in order to argue against Si's desire for more precision in ski terms. PMTS is more precise about these definitions. Active steering involves muscular effort in the direction of the turn. Passive rotation of the joints as a facilitating act is not steering. In fact not much is said about passive rotation in Harald's books or PMTS materials because it is not something one can control -- i.e., it's a passive effect. The thing that makes the turn are the other primary movements.

The description should help one see why even very good traditional skiers look to be almost flailing in their movements to a PMTS eye and why PMTS skiewrs look obsessively "hunkered down" to a traditional eye. In any case the difference in movement patterns is very noticeable.

With all this said I would point out a seemingly subtle though I think crucial difference in our interpretations of Harald's writing.

[Quote="ydnar"]Harald's first two books the idea was that a simple basic movement, a cue if you will, will serve to activate the kenitic chain and result in the necessary movements of the larger parts of the body without having to focus on conciously moving those large powerfull body parts with the added plus that recruitment of the large muscles in this manner means that they will be less likely to make overpowering movements.[/Qoute]

If I understand things correctly the point is not to avoid conscious use of rotation originating in muscle groups higher in the kinetic chain, so that you don't do it too much. The point is not to "use" those movements (muscles) at all to rotate into then turn. Any leg rotation that originates in the muscles of the leg that actively rotate the legs into the turn shoud not be used. If they happen passively, that's another issue.

The movements lower in the chain do not "lead" to "necessary movements of the larger parts of the body. " The lower chain movements are sufficient in themselves. They are primary. Movements higher up either facilitate or get in the way. I think they are referred to as "secondary movements" in the books and PMTS manual. It is not that movements in the foot and ankle "cue" the legs to actively rotate. The tippping and flexion effort is enough in itself to make the turn. This may seem like a small difference, but I think it's important. Maybe, Harald can comment of this.

By the way, a similar distinction is what is behind upper body movements in PMTS: turning to the outside of the turn early (counter action) and progressively following the skis with the body until one is square to the skis at the transition. Again, this is opposite of the traditional notion of leading with the body into the turn (committing with the hips and shoulders and staying square to the fallline) and countering to stay square with the falline at the end. Maybe someone else will extend that discussion. The first is designed to prohibit and control rotation into the turn, the other attempts to actively use it.
Last edited by SkierSynergy on Fri Oct 22, 2004 2:31 pm, edited 1 time in total.
SkierSynergy.com -- comprehensive services for the girlfriends of skiers
SkierSynergy
 
Posts: 305
Joined: Tue Jul 20, 2004 11:05 am
Location: Mt. Hood -- Portland Oregon

Postby piggyslayer » Thu Oct 21, 2004 7:41 pm

Harald, thank you for these kind words, I learn a lot from the forum, reading and posting here motivates my learning. I think the forum is a great idea, it is a bit of like having a look into chefs kitchen and see what is cooking. Reading your Instructors Manual was/is a great eye opener for me. What is the most fascinating for me is that the more I learn PMTS, the more I see how much thinking and science went into creation of PMTS.

Learning PMTS and skiing PMTS is fun. The rest is politics and that is always ugly. Each time there is a new way of doing things which contradicts status quo there will be people extremely aggravated by it. I know this is an outsider observation and it is easier for me to say it than for people involved to live it. But I hope the seed is planted, however small the group of PMTS-ians is, we will get better and better, and we will be easy to notice on the slopes and others will follow.

Thanks for spending time to answer my posts and for always being there to help me and my wife with skiing questions and problems.

Robert
Piggy Slayer
let the piggy breathe
piggyslayer
 
Posts: 320
Joined: Tue Nov 04, 2003 9:27 pm
Location: New Jersey

Next

Return to Primary Movements Teaching System

Who is online

Users browsing this forum: Google [Bot] and 71 guests