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Feet stuff with Tom G.
It's not so much his height as much as the very straight upper body. Deliberately.
CSIA seem to prefer more hunched over - the 'bad dog' posture as one instructor put it.
I'd only ever seen a couple of his youtube vids, but picked him out on the hill in an instant the 1st time I saw him in real life.
Some folks' style just lodges in the mind. Can pick them out on a crowded hill at long distance. (Unfortunately not always the good styles.
I like how Gellie describes the use of “static” gravity to encourage an efficient “home based” flexion in our stance. This is the fore/aft stacking that is the most efficient, effortless and powerful. When we feel the forces of the turn, whether centripetal G forces and/or ground force reaction, compel itself onto our stacking and to compress the skeleton vertically, we want that pressure to transmit directly down through our feet at the cuff, ball and directly to the edge between the toe piece and shovel. Not rearwards to the heels and backseat hips where muscular activity is forced to maintain our upright status under the G’s in mid turn. While we may utilize a backseat “position” to mobilize retraction, that is during transition and not while these forces are at play. The key to this and any great skier’s aesthetic is also the key to their cost/benefit, effort to energy ratio. Skiing is where superior function is the superior aesthetic form and not anything else.
I don’t know how well you can see the diagram below of the CoM and the arrows pointing the direction it will go depending on your fore/aft stacking position, its resulting load bearing axis and how to use static gravity to support that position and outcome. A more upright stance over the front cuff and ball in well “fore/aft dialed” boots and more forward oriented stance over the forefoot/ball is what Gellie demos and explains so well.
Gellie’s stacking on the left and Curious George’s stacking on the right:
…. And let’s not forget about the metatarsal lever [lee-ver] that we use to control the tip to tail migration of pressure/load on the ski. Keep in mind that we need not actually “lift” our heel (or ball for that matter) to activate the metatarsal lever to shift all our pressure-weight-load to the ball to press the shovel into service and then all to the heel to ride the tail out of the turn. A few millimeters of vertical tension in the boot will suffice. Keep in mind that we only get navicular pressure for ankle tipping while on the ball and not on the heel which is why it is a “turn phase one” motor pattern and dorsiflexion is a “turn phase two” motor pattern. The powerful calves required are actually one of the easiest strengths to develop for most people if they wanted to develop a “skiing from the feet” advantage.
One of Gellie’s mentioned philosophies suggests that, if we were to redesign the ultimate human body based on the best skis available today, we could not do any better than the original human anatomy we are given. I agree. On skis, we are all high end machines. You just have to be able to conceive it that way to see it that way and then to ski it that way. As soon as we are able to translate everything and anything an instructor or coach may say to us to what our bodies, balance and proprioceptive feedback is saying to us, the need for that external verbal dialogue becomes less and less and, only then, do we become truly free to fully express ourselves on a pair of skis. The words in your head need to start coming from you and not other people. From where I sit, that is the key difference between an advanced intermediate and an expert skier.
Very interesting Doby. I'll have to think about it a bit more. It does seem to me that curious george's flexion will provide greater access to tipping of the lower leg though...
Mike
Mike
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Not sure how you come up with that.
How is " navicular pressure" only at initiation phase and only on the ball of foot? One has to be on ball of foot to tip the foot to big toe side? The navicular would be involved in any loading of the medial side of the foot. Or in pronation/supination.
It's hard to find depictions of anatomy actions in closed chain conditions.( foot fixed or in ground contact) Here's a general one. Seems to me the navicular is always involved.
As for part two, Reilly McGlashan would disagree I suspect, as would the multitude of people constantly lifting the toes to tense their foot. According to @Mike M 's report of McGlashan's clinic where the toes are lifted to set the heel and base of foot in footbed. Not lift it off.
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Re: straight vs hunched back. This is a subject of debate in the CSIA with no firm consensus on the matter.
The CSIA was definitely pushing the "Canadian Crouch" for many years, as seen with the demo teams of the last decade or so. I was drinking from that koolaid too and used to tell my customers/trainees things like "Imagine you're Quasimodo, not Urkel!!!!" It comes from Alpine Canada (racing) dogma where, for maximum mobility for high performance, the racer should bend the spine (in all axes) too.
In recent years there has been some pushback on this, especially since the CSIA is geared toward the recreational market where efficiency and spinal health should be prioritized. My own physiotherapist once worked for the Canadian national ski cross team and now advocates for a "neutral" spine because of all the "f***ed up backs" he saw racers end up with. And lately I've been hearing some senior CSIA peeps (e.g. Kristian Armstrong, BC Coordinator) suggest a "straight" back for the same reasons.
The CSIA was definitely pushing the "Canadian Crouch" for many years, as seen with the demo teams of the last decade or so. I was drinking from that koolaid too and used to tell my customers/trainees things like "Imagine you're Quasimodo, not Urkel!!!!" It comes from Alpine Canada (racing) dogma where, for maximum mobility for high performance, the racer should bend the spine (in all axes) too.
In recent years there has been some pushback on this, especially since the CSIA is geared toward the recreational market where efficiency and spinal health should be prioritized. My own physiotherapist once worked for the Canadian national ski cross team and now advocates for a "neutral" spine because of all the "f***ed up backs" he saw racers end up with. And lately I've been hearing some senior CSIA peeps (e.g. Kristian Armstrong, BC Coordinator) suggest a "straight" back for the same reasons.
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Yes, I see and appreciate the discrepancy you raise. However, if that video were to include dorsiflexion, we would see something different. I am speaking from the standpoint at which anyone reading this can immediately see for themselves what I am saying so we won’t have to rely on finding the “right” words to explain detailed biomechanics. So, for a minute, forget everything else and try the following: First, while standing upright, try rolling out the ankle/navicular on an upright, non-dorsiflexed inside leg (like the diagram below) and notice the ease with you can roll/invert the inside ankle outwards (to the inside of the turn) onto its outside ball and arch and pushing the navicular against the outer shell of the boot as depicted below on the right. Either open or closed chain. Now, try to maintain that ankle inversion that moves your navicular out and start dorsiflexing your ankle. You will see that you can no longer maintain that ankle inversion as your knee moves forward to create ankle dorsiflexion. The navicular moves back in and away from the boot shell. By turn phase two the pinky toe carving is no longer essential as the outside ski takes over and maintaining pressure until it becomes the new inside ski pinky toe edge once again. As a matter of fact, the more plantar flexion we create, the more ankle inversion is possible. You may also see that all diagrams that show inversion/eversion of the ankle are with no dorsiflexion. The reason why you won’t find one is because the two movements are incompatible (mutually exclusive mobility) and why they do not really occur within the same timing/turn phase. The benefit of lack of inversion and eversion during dorsiflexion is the increased lateral stability that we want through the heavily loaded dorsiflexion phase of the turn (phase 2 & 3) and an example of why stability and mobility are often mutually exclusive in the biomechanical context. All our joint’s range of mobility are almost always dependent on the position of the next adjacent joint such as is the kinetic “chain”. We are all familiar how the rotation we get from the hips down and through the legs is in different places when our knees are bent 90 degrees in transition compared to when they are only bent 30-45 degrees in phase 2. We also have more rotational capacity in closed chained or edge locked carving vs open chained or a skidded engagement, something Gellie touches on over a recent post of his on another thread. While an edlocked turn is "closed chain" and the foot lifted off the ground is "open chain", a non edgelocked but skidding ski is semi open/closed chain, a transition of which further complicates the details.
Oh, sheeet. I didn't realise a session of AIA had been scheduled.... (Actually, it's all good stuff, thought provoking stuff. Nerdy, but good.)
Well, that's interesting. Kristian was one of my assessors for L3 teaching component and that fits with a comment he made on the eval form about assessing 'students' that I was a bit puzzled about. The 'bad dog' comment was over a decade ago and can't recall any of the CSIA instructors making any comments about back posture recently.
"tomgellie" is a member here, don't know if he wants to particaipate but you could page him.
I've spent a fair amount of time on his platform, he's got some good ideas for sure and his skiing is enjoyable to watch.
I've spent a fair amount of time on his platform, he's got some good ideas for sure and his skiing is enjoyable to watch.
LF, just to be clear...when standing statically in shoes, you feel a definitive pressure bias in your forefeet? Is there more weight in one forefoot moreso than the other? Have you assessed your footpressures barefoot?
If someone were to view you from the side, again standing statically, would they observe your pelvis as being tilted sagitally forward or rearward, or somewhere in between?
I may have some ideas for you but I’d need more info....
zenny
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*word of caution, sometimes what ppl say they are doing is nothing close to what they are doing.
Great series of posts Doby. I tried this test. What I found depends on how I tip the foot. If i tip it and lift the bte metatarsel and toe it happens just as you say. However, if I tip my foot and simultaneously press down the big toe and aim to keep the bte metatarsel down, it does not happen. The navicular bone keeps more or less the same lateral tipping. When you tip the foot inside a tight boot I don't think you can lift the BTE side very much, hence I think the second method of tipping the foot is more like what you do while skiing.
Thanks @Jamt, I hear what you are saying and I think I may have that considered. However, not in line with the prevailing thinking about the navicular. The reason being is because, while we do articulate the inside ankle laterally, inversion, to carve the little toe edge, we do not articulate the outside ankle in the same direction beyond the state of “neutral” stacking so that its laterally neutral and strong to bear the primary load of the turn. In other words, big toe pressure requires no ankle eversion because that is destabilizing. Good ankle movement isn’t just about tipping that inside ski into the turn but also maintaining the strongest load bearing axis of the outside ski. That is neutral stacking without any ankle inversion or eversion. The “stability triangle” discussed above is only “stable” when it is stacked neutrally against the returning forces of the ski. When it is tipped off or away from the central load bearing axis, it becomes a “collapsed” ankle which is weak and that which is OK for the inside but not the outside. As far as I am aware, the navicular (really the cuboid on the outside of the navicularis) only moves out with ankle inversion not very far inwards with a neutrally stacked ankle. Good “ski boot fit support” prevents outside ankle eversion or, collapse, and good “ski boot fit mobility” encourages inside ankle inversion. Outside ankle eversion contributes to “A” framing (of the outside ski) and is preventative to the equal tipping and parallel shafts that inside ankle inversion works to achieve. All that said, I do believe the navicular does move to both the inside and the outside to some degree. For me, the focus is to press it to the outside and move it back in but not past neutral. So, for me at least, I really want space in my boot to move the cuboid towards the outer shell of the boot and not so much the navicularis to the inside of the boot shell if that makes any sense.
The straight and stacked load bearing axis of the outside ski:
Works the same for skating:
Below, we want the angle of the ankle in the middle foot for the outside ski and the ankle angle on the right for the inside foot. The foot on the left is a “collapsed” and weak ankle position for an outside load bearing foot.
Navicularis and the cuboid:
The straight and stacked load bearing axis of the outside ski:
Works the same for skating:
Below, we want the angle of the ankle in the middle foot for the outside ski and the ankle angle on the right for the inside foot. The foot on the left is a “collapsed” and weak ankle position for an outside load bearing foot.
Navicularis and the cuboid:
The rightmost setup is not in balance. There is a resulting moment which is non-zero.The straight and stacked load bearing axis of the outside ski:
This moment has to be taken up by the contact point between the foot/leg and the ski boot.
In this picture is seems the force would be way inside both the ankle joint and the knee. You would have to push the knee inside. However, if you allowed the foot to evert a proper amount the knee would also move to the inside. Everting does not necessarily mean that you are collapsing the foot arch.
David McPhail has an interesting website discussing these aspects a lot https://skimoves.me/
Pronation in the closed chain = the suspension phase wherein we can sense the ground and gather information about the surface. This suspension phase during gait is fairly brief, the rest of the time we spend on that foot is spent moving back towards supination (the foot re-supinates) the arch forms and the foot becomes rigid. During the brief pronation (suspension) phase, the talus is internally rotating which helps facilitate movement in the leg (not to discount the glutes, psoas, etc) so we observe internal leg rotation and adduction. This is significant in skiing very early on in the turn (and actually starts during ‘finishiaton’) because of, in part at least, of the everting paths. The foot and ski (outside) continue in one direction as the ski rolls over and the new turn begins whilst the leg begins to rotate out from the old turn and into the new. So a sort of ‘countersteering’ as Tom discusses in the videos. Now of course this pronation (to include eversion) of the foot is indeed not a ‘strong’ position, but that’s ok as there are no significant reaction forces yet, those come shortly thereafter. Which brings up....
Supination = the propulsion phase. As mentioned above this is when the arch begins to form, and the foot starts to become a rigid lever (perhaps a pseudo windlass, as the heel will generally remain planted). The talus will begin to externally rotate as will the leg. So we observe external rotation and abduction of the leg. This ‘re-supination’/supination phase (aka propulsion) takes up the preponderance of a ski turn (again, on the outside leg) just as it does during normal and efficient gait, and the strongest anatomical stacking can be found during it. A word of caution though, this is (or should be) fluid, we are never statically stacked, rather, optimal stacking is a moment in time....
Similarly, the inside foot goes through its phases in a ski turn but it is important to note that it very well may be more towards the open chain end of the spectrum as noted above. So again starting during ‘finsihiation’ the old outside/new inside nearly completes its supination phase (continued from its load bearing role during the old turn), gets unloaded (via flexing/relaxing) and then inverts in much the same way it would after toe-off durning gait. Important to note is that we see leg flexion, external rotation and abduction of this leg. But this too doesn’t last forever. As the turn progresses past the loading of the outside ski and balance begins to transfer to the Lte of the inside, we will then begin to see that foot to enter the suspension (pronation) phase once again. And now we have come full circle, so to speak . :-D
This is why (I’m pretty sure as I’ve spoken to him a few times about this very matter) Tom has the trainers in the vids feeling and noticing foot pressures throughout all phases of the ski turns and why he encourages the countersteering and other movement patterns. IMO.
It should be noted of course that this is all ideal. By that I mean not everyone can strongly form an arch with their feet, many are stuck in pronation with one or both feet. Many have weak feet, rigid feet, forefoot varus, calcaneal eversion/inversion, the list goes on and on....incidentally a lot of the can be remedied through work, and IMO orothotics are not always the best answer? Perhaps strengthening and improving foot/leg/hip/pelvic alignment is that way to go for some? This is the journey I have been on and am still on.
Just some thoughts. I said some unconventional things, should precipitate further discussion
I did NOT proof read this, hopefully it makes some kind of sense!
zenny
Supination = the propulsion phase. As mentioned above this is when the arch begins to form, and the foot starts to become a rigid lever (perhaps a pseudo windlass, as the heel will generally remain planted). The talus will begin to externally rotate as will the leg. So we observe external rotation and abduction of the leg. This ‘re-supination’/supination phase (aka propulsion) takes up the preponderance of a ski turn (again, on the outside leg) just as it does during normal and efficient gait, and the strongest anatomical stacking can be found during it. A word of caution though, this is (or should be) fluid, we are never statically stacked, rather, optimal stacking is a moment in time....
Similarly, the inside foot goes through its phases in a ski turn but it is important to note that it very well may be more towards the open chain end of the spectrum as noted above. So again starting during ‘finsihiation’ the old outside/new inside nearly completes its supination phase (continued from its load bearing role during the old turn), gets unloaded (via flexing/relaxing) and then inverts in much the same way it would after toe-off durning gait. Important to note is that we see leg flexion, external rotation and abduction of this leg. But this too doesn’t last forever. As the turn progresses past the loading of the outside ski and balance begins to transfer to the Lte of the inside, we will then begin to see that foot to enter the suspension (pronation) phase once again. And now we have come full circle, so to speak . :-D
This is why (I’m pretty sure as I’ve spoken to him a few times about this very matter) Tom has the trainers in the vids feeling and noticing foot pressures throughout all phases of the ski turns and why he encourages the countersteering and other movement patterns. IMO.
It should be noted of course that this is all ideal. By that I mean not everyone can strongly form an arch with their feet, many are stuck in pronation with one or both feet. Many have weak feet, rigid feet, forefoot varus, calcaneal eversion/inversion, the list goes on and on....incidentally a lot of the can be remedied through work, and IMO orothotics are not always the best answer? Perhaps strengthening and improving foot/leg/hip/pelvic alignment is that way to go for some? This is the journey I have been on and am still on.
Just some thoughts. I said some unconventional things, should precipitate further discussion
I did NOT proof read this, hopefully it makes some kind of sense!
zenny
It is really difficult to translate this stuff back and forth and I am a bit lost with your wording. I use the term "collapse" in regards to lateral ankle movement and not the arch. Regarding ankle "eversion" I do believe that is a move we use but only to get the ankle un-inverted and back to neutral. For me, the equitability of neutral stacking is the key to both effortlessness and power. That said, good stacking happens slightly prior to the forces they are designed to meet. Stacking needs to be proactive rather than reactive and therefore, slighlty ahead of the curve of building forces. The photo above is just to represent what I mean by the load bearing axis and I agree that the outside foot on the right would need to be tipped (by the leg rather than the ankle) to be balanced against turning or even standing forces if that is what would be happening in that diagram. If not, it would be a strong movement of ankle eversion to keep that ankle from collapsing to the outside. It can be very difficult to find and use the correct diagram or video to support a single point when it can often be used to make a conflicting point.
I think it is either you or Zenny who bases significant focus on a collapsing arch whereby I do not. There is a major division between bootfitters regarding a footbed supported and unsupported arch and I know which side you are on. I feel that the idea of a collapsing arch may be relevant to basic physiopedia in street shoes but do not see the logic translating directly to the foot in a ski boot, which to me a completely different biomechanical context and perhaps a discussion for another time. I have read a lot of yours and Zenny's and a few other's posts and find that 90% of any discrepancy in understanding lies in the wording, phrasing, conceptual framing its interpretation thereof rather than our core of understanding. Nothing is black and white, nobody is either 100% right or wrong and navigating the spaces between is not for everybody. I use a lot of wording in order to manage the highly variable context in which ski technique discussion must navigate to shrink those spaces but that which can never be eliminated altogether. It is great that there are at least a few folks here willing to tackle such a challenge.
@Zenny, great post. Yes! Stacking is fluid. The term stacking has a tendency to denote staticity. ... and yes, we often need to speak in ideals unless we are speaking on individual and/or their flaws, that of which we all have Though, I feel that speaking in absolutes is never a good idea as in there are really no “absolutes” in skiing. As an example, “perfection” is an absolute that leaves no room for the interactive margins of interpretation. Instead, I prefer to speak in ideals. An ideal is more of an immeasurable infinite than a specific absolute. Much of my writing is speaking in ideals in that it leaves room for the variables of interpretation which, in turn, leaves room for all the variables an individual brings to function in a manner that perfection and absolutes are not capable. The ability to hold two opposing ideas in mind, one our own, and find truth and falsity in both is a sign of good thinking.
Talking about ski technique and bio mechanics can be difficult, in particular on the internet.
You can evert the ankle by collapsing the arch, which is something that some people here advocate. I'm strongly against this since I don't believe that is a strong position to handle large forces, it kind of forces you to balance over the heel. You can also evert with strong arch. I want the ability to regulate the tipping of the foot, and that will mean I will feel the forefoot center of pressure change. When it is around the first metatarsel I will have strong grip. When the ankle is neutral it will be spread evenly and the grip will be in the borderline between edge lock and skidding, when it is closer to the outside of the foot I will be skidding/sliding.
My previous point was primarily of what neutral means. In the picture the ankle can be neutral, but not the knee.
Basically you may have to sacrifice the neutrality of the ankle, otherwise the boot will push on the leg.
I think it may be useful to look at what happens when the foot lengthens and the forefoot spreads a bit. I don’t like the verbage “collapse” as it implies a weakness or that something is wrong. But when the plantar fascia lenghten and spread under the initial contact, the tissues underfoot load eccentrically, which perfectly sets us up then for a strong concentric contraction i.e, a supinatory response and a stiffening of the foot...
Again, this presupposes an already strong foot which more than a few do not possess from what I understand.
Any arch flattening via initial reaction forces would of course have to very brief because it is the suspension phase, and is not strong as we all agree upon. It is therefore crucial one can muscularly form the arch and if not some support (small or great) underfoot is needed...
So let’s say you are set up neutral such that your hindfoot cannot evert and your arch cannot deform which is very common. You are then already in a resupinatory foot position and the availability for further contraction is diminished, in part because the arch is already formed and also because the muscles are in an already shortened, yet less active state (because the arch is being propped up with minimal muscular input)...there then is an actually diminished capacity to make the foot a rigid lever manually.
In general though, I think foot pronation gets a bad rap or is at least misunderstood like a bad stepchild :-D
zenny
Again, this presupposes an already strong foot which more than a few do not possess from what I understand.
Any arch flattening via initial reaction forces would of course have to very brief because it is the suspension phase, and is not strong as we all agree upon. It is therefore crucial one can muscularly form the arch and if not some support (small or great) underfoot is needed...
So let’s say you are set up neutral such that your hindfoot cannot evert and your arch cannot deform which is very common. You are then already in a resupinatory foot position and the availability for further contraction is diminished, in part because the arch is already formed and also because the muscles are in an already shortened, yet less active state (because the arch is being propped up with minimal muscular input)...there then is an actually diminished capacity to make the foot a rigid lever manually.
In general though, I think foot pronation gets a bad rap or is at least misunderstood like a bad stepchild :-D
zenny
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I agree, nothing wrong with pronation. Over-pronation though...
