Body Mechanics discussion

A snowHead

Instead of discussing geometry and carving how about talking about biomechanics and what the body can and cant do when skiing. As we have numerous medics on snowHead

's hopefully they can chip in along with a few people that like debating about "how skiing works".

I will kick off with an explanation on why I think doing braquage drills for upper/lower body separation can create bad habits.

Each lower joint has a range of movement. Sit at your desk and hold you shin still you can only move your ankle a few degrees back and forth. now hold your knee still you can move your foot about 10 degrees inward and 20 outward. now stand up and bring you knee up off the ground and swing your leg in and out keeping hip perfectly still...i can get about 60 deg out and 20 inwards.

so without twisting the upper body i recon my joints will let me move one leg outward around 80 degs, but the other leg will only move inwards 30 or so.

This will obviously vary with individuals but the principle i think holds for most skiers. If you wish to rotate the lower joint separately from the upper body using only the lower body you are constrained and by doing "full" 90 degree across the slope braquage you must twist the upper body which is not generally a good thing. so perhaps a better form of braquage is not to try to get to 90 deg across the fall line but do say 45 deg each side to ensure upper lower body separation by only moving the lower joints.

Discuss and please add any other thoughts with regards to body mechanics.

A snowHead

There are two pivot points for separating upper and lower body: hips and waist. Most people use both their hips and waist when doing braquage drills, and it's possible to sweep the skis more or less 180º. The femur in the hip socket has, as you say, far less rotation available, so it's not possible to get the skis all the way from one side to the other, although using rotation in hip sockets-only for me is a much quicker way to change the skis' direction (in bumps, for example). A good exercise to focus on using rotation from the hips only is to hold a ski pole horizontally in both hands and push it so that it rests across your pelvis at hip level. Then do a braquage drill, but make sure that the ski pole does not have any rotation.

Well, the person's real but it's just a made up name, see?

rob@rar, skimottaret, Did your instructor courses give advice on what to do with skiers that have joint mobility problems? I have quite restricted knee and hip (1) movement and have really struggled with some exercises.

You need to Login to know who's really who.

skimottaret, Interesting post. As a fairly new skier I've been told numerous times, by people with a lot more experience than me, that I should 'keep my upper body facing down the fall-line'. This details pretty well why I think that's just about impossible for a learner, when skiing wide zig-zags across the fall-line.

I guess one argument for the practice sessions might be to try and increase the range of motion in the joints? (One for the doctors and physios?) Any improved mobility might then help with technique in turns. However, there does seem an obvious risk of ingraining bad habits of body rotation, as you point out.

Anyway, snowHeads is much more fun if you do.

skimottaret,

and then there is the question of how much counter you really want to ski with.... Except for doing a hockey stop and those pivot slips that Vail Sno Pro is doing I'm trying to think of other times I'd want as much counter as he develops at skis perpendicular to fall-line...

Surely it is a higher priority for most folks to learn to use appropriate counter than to learn to isolate femur rotation in hip socket so they can do those drills well?

You'll need to Register first of course.

skimottaret, little tiger has a good point. In the CSIA/CSCF, we have gone away from "forced" seperation, to "natural" seperation. In a nutshell, create seperation with the femur/hip socket as much as you can, and then if you still want to turn those skis further round, the hip (waist) as rob@rar alluded to has to rotate.

(However for the purposes of instructor exams, there are still quite a few old school examiners out there who want to see only femur rotation and zero hip/waist rotation).

This is kinda linked into counter, and tiplead (!) as well.

The days of deliberately creating counter should be well gone, and counter should be as a result of natural seperation.

However, braquage, done correctly, is still an excellent (high level) drill to free up those muscles and ligaments, plus you need that mobility when you are doing say short radius turns, and bumps, as any unwanted rotation (hips upwards) will be inefficient.

The other benefit of braquage, is, edging. The big thing at the momrnt is "pivoting to create edge angles" (another highly contraversial topic).

So to summarise my thoughts on braquague - It is an exceedingly useful drill, but only if you have the correct goals and outputs in mind.

Then you can post your own questions or snow reports...

After all it is free

*Ski* the Net with snowHeads

snowHeads are a friendly bunch.

rob@rar, you really want to raise this??!! Wink

A few schools of thought, amongst others:

1. Edging is all about lateral movements, and tipping. Therefore no rotary movements should be patterned. Ever.
2. Edging is all about lateral movements, starting with the ankle, to set up the kinetic chain, but to create the large angles, you need to rotate/pivot your femurs.

snow reports

You know it makes sense.

Otherwise you'll just go on seeing the one name:

A snowHead

A snowHead

rob@rar, thus pivoting to create edging Wink

But there are definitely race gurus out there that don't allow their athletes to do any braquage at all.

Well, the person's real but it's just a made up name, see?

veeeight, Not the ones I know.... canadian provincial coach, italian national team coach etc etc .... I've done my share of these things with those guys...

You need to Login to know who's really who.

Anyway, snowHeads is much more fun if you do.

Frosty the Snowman, do you adequately warm up prior to skiing or attempting movement exercises? I have arthritis and find that unless i am warmed up i really struggly with hip and knee movement exercises...

if there is a restricted movement you might need to find a compensation through moving other joints. Not everyone has high levels of flexability and the advice is work with what you have..

You'll need to Register first of course.

little tiger, veeeight,

Then you can post your own questions or snow reports...

Frosty the Snowman, IIRC Fastman has a buddy with a fused ankle who apparently skis at a pretty high level... You might want to see if he can shed any light on this stuff... Failing that find an instructor with some training in disabled skiing? I know many of our guys take Disabled course to make the ISIA second discipline requirement... in USA this is not very prevalent... and the Disabled schools seem more separate and less integrated...

After all it is free

skimottaret, ummmm I'm not of that school of thought re counter... I just think you need to learn to use appropriate counter... Getting all hung up on femurs in hip sockets does not seem the best way to focus on this IMHO - and remember I did spend many many many runs skiing with hands on knees/hands on hips/poles strapped around butt/etc etc etc in order to improve awareness of body position and learn separation...

Actually I think I improved a lot when Fastman taught me to create early counter rather than sit and wait for it to "just happen"..... That is another controversial one though!!! Twisted Evil

Frosty the Snowman, LT's post reminded me that I skied with a guy this season who had one foot that splayed outwards about 20 or 30 degrees after a very bad footy injury. his knee got sore when skiing but he manged to pass the Eurotest in that condition so the body can definitely compensate to stiff or misaligned joints. snowHead

little tiger, hmmm so you recon that creating counter as opposed to counter being a natural occurrence during skiing? I personally think we should counter a bit to initiate turns and that this can happen through projecting the body across and forward into the next turn whilst separating the upper and lower body.

*Ski* the Net with snowHeads

skimottaret, umm, hard to put into words, but when observing with a good eye, you can tell if a person has reached the end of their femur rotational limit or not. Watching Vail Sno Pro in the animated .gif above he has got an excellent range of femur rotation, before his hips start coming around.

Natural separation is evident when it is created as a result of the legs turning under the body, and not the body twisting (countering) first.

Here's the lovely Deirdre performing the Central Theme, but in her snowplough and plough parallel, she is displaying ZERO separation (and even rotating on some of her R turns Wink

) - some natural separation is shown when she gets to the parallel stage.

http://youtube.com/v/WFX7Cr3giXk

And someone with *superb* separation: Very Happy

http://feat.putfile.com/flow/putfile.swf?videoFile=RB-Ski-Classic-Short-Radius-Turns

snowHeads are a friendly bunch.

snow reports

Ahhhhhh..... but in modern slalom, you may have observed that the counter *point* has risen higher over the last few years, so in that instance they are countering with their upper back and shoulders, however, everything below the waist is still working as normal.

Whoo Hoo, when did this start? Laughing

You know it makes sense.

veeeight, fair enough on SL but i was thinking more of a GS type turn.

Otherwise you'll just go on seeing the one name:

Mind Mechanics. Cool

http://youtube.com/v/1r6gIBCMVLI

A snowHead

A snowHead

what about the back? safe and unsafe motions for the spine

SAFE: flexion extension front to back and rotational top/bottom
UNSAFE: tilting sideways!!!

i recently heard that there are 2 independant instructors in the US being sued right now for teaching an exercise involving an unsafe motion for the spine, there federation [PSIA] won't back them as ''they weren't taught to teach that drill'' they claim they were taught to teach it but not by the PSIA

Well, the person's real but it's just a made up name, see?

You need to Login to know who's really who.

This is a pretty good braquage sequence, I'd say 7.5 out of 10...... Smile

http://youtube.com/v/w63-yma3M_Q

Anyway, snowHeads is much more fun if you do.

veeeight, Piste is Past, Freeride, who want's t ski the piste?

You'll need to Register first of course.

skimottaret, excellent topic. Seems there's always a lot of question in regard to counter. First, consider it's purpose. Counter, combined with a forward posittion of the CM pronates the outside foot. That directs the pressure on that foot to the big toe side, which serves to positively engage the inside edge of the outside ski,,, exactly what we want. For that reason alone, establishing early counter is very helpful.

Another purpose is balance related. To stay balanced on the outside ski we often need to move our Center of Mass toward the outside ski. We do this by bending our body toward the outside of the turn at various joints. We call it angulation. Lateral flexion at the waist, and in the spine, has a limited range of motion, so we can only move our CM laterally a minimal amount via that manner. By countering our hips and upper bodies such that we face toward the outside of the turn, we can flex forward and move our center of mass further in the direction of our outside foot. This is because our forward flexion range of motion at the waist is much more than our lateral flexion range of motion. The more we counter, the further outside we can move our CM.

At low edge angles, this is not a crucial need, as the need for angulation grows as we increase how high we tip our skis on edge (called edge angle). Thus, when steering turns at low edge angles, little counter is required. Speed also plays a role in how much angulation is needed, as does your skis sidecut. At the same speed and edge angle, a ski with a smaller turning radius (more sidecut) will carve a sharper turn, thus producing more turning forces, and requiring less angulation to stay in balance. Different body types too plays a role in how much angulation is needed to maintain balance.

So,,, put it all together and determining how much counter is needed can get very complicated. Add to that, many different degrees of counter can be used by the same person with equal success, depending on how much you flex within that countered position. This shows very clearly on lthe WC, where skiers will show a variety of countered states, yet all perform at a World class level. The amount you counter can very much be up to personal discretion. In fact, part of my teaching is encouraging people to explore different states of rotation, and varying those states as they turn,,, just to gain comfort and versatility on their skis.

As far as when to initiate counter,,, as an ideal I encourage an early establishment, so as to create outside foot pronation, which will solidly engage the new outside ski early in the turn. That early counter is established in the manner skimottaret suggested. As you go through the transition, you extend the new outside (old inside) leg, which moves the hips and CM forward. As you do that, you drive the new inside hip forward, which creates the early counter. It does not have to be a drastic amount created early. Just a slight forward drive of the new inside hip will create all the counter you need to pronate the foot. From there you can add more as needed as you go through the turn and increase your edge angle.

You will see expert skiers (WC skiers) sometimes appear to go through the transition and into a turn actually rotated downhill. This is called an anticipated position,,, or "anticipation". Pay close attention to whether their transition into the new turn is arc to arc, or pivoted. While sometimes the anticipated position is a result of a delay in negating the strong counter from the previous turn (called skiing into counter), often there is a pivot involved in the transition, and the anticipation is being used to help power that pivot.

Which gets me to one final idea I need to share. Learning skiers who are still at the steering or low edge carving stage can be ill served by trying to use too much counter. At this level little angulation is needed, and using too much counter can put the skier in an anticipated position that actually encourages a pivoted transition. At the intermediate level a pivot is a common flaw that needs to be overcome,,, not encouraged even further. Squaring the stance such that only the minimal counter needed to pronate the foot, and maintaining that stance through the duration of the turn, will help promote a cleaner and more subtle entry into the new turn, while putting the skier in a more comfortable and functional stance from which to execute quality steering.

Then you can post your own questions or snow reports...

After all it is free

*Ski* the Net with snowHeads

You could have a go at some analysis? Laughing

Help!!

Body Mechanics discussion

snowHeads Forum Index >>> Bend ze Knees