And I'm now in the place where I do need a lot of free skiing to move toward autonomy.
Mike
Ha! You want to be autonomous like a hippopotamus. They tend to go exactly where they intend.
Mike, I think that the major conceptual division between your’s and LF’s description is whether one skis “from” the feet or skis “from” the hip. The former being more of a race coach construct vs the later, a more conventional and programmatically academic construct of instruction. Because skiing from the feet heavily relies on the contact pattern between the shell and foot, it is a “hidden” skill (can’t really see what is happening inside the ski boot) and therefore is not very conducive to the process of visual demonstration which is a staple modality of conventional instruction. If you can’t see it, you can’t be “shown” how to do it. Other than talking about it, an instructor can not demonstrate the most sophisticated and technically significant aspect of modern ski technique which is the relationship of the foot, ankle and lower shin to the inner shell of the boot or, referred to above as the “contact pattern”. Of course, minimal boot fit, function and performance will be key. A skier’s ability to find, tweak and ski the right boots has to develop along with their ski technique. The foot and ankle is the most biomechanically superior joint on the entire human anatomy and, as well, the only one that has immediate contact of 360 degree control with the ski boot/binding/ski as one unit. In regards to overall strength/power, balance, control, and precision the foot/ankle offers us in athletic performance capabilities, nothing else comes close. Where the foot, ankle and lower shin provide “direct” input to the ski to and through the hard boot shell, hip flexion and extension are merely “indirect” inputs (or outputs) where the ski is considered.
To me, skiing “from” a certain part of the body refers to where the primary kinesthetic focus is for turn initiation and timing of the entire kinetic chain turn cycle. It is where the DIRT that is utilized for the entire turn is being allocated, assigned and initiated. Using either flexion or extension to tip the skis is, literally as much as figuratively, putting the cart before the horse resulting in more work and an unnatural, augmented timing that is difficult with which to achieve good flow. “Active” leg shortening or active flexion such as “flex to release” is a physical input that some use to initiate of the kinetic chain turn cycle. Lifting to shorten the inside leg, forced retraction, forced initiation or an overtly instigated timing of flexion and extension is an active input that requires contractions of the hamstrings, hips and abs and is the primary force a skier will use to get the skis and legs tipped over. While using these motor patterns, specifically, as a spiral focus for development may be helpful, this “kinetic path” routes from the hips down to the feet and is longer (distance between CoM & BoS), slower (large muscle contractions vs the quick twitch ability of the ankle) and more laborious (active input/effort vs passive output/no effort) than skiing from the feet. However, when the ski is tipped with the feet and ankles as the initiating event in the turn cycle, inside leg shortening becomes a product of simply being loosey-goosey over the resultant ground force reaction of equally tipped skis which will force vertical separation of the feet (aka passive inside leg shortening). When skiing from the feet, leg shortening (flexion) is a large passive output resulting from the small active input of ankle tipping against the boot. Skiers that ski from the feet maintain constant dynamic tension (fore to aft and lateral) in the foot and ankle that is the equivalent to having your hands on the steering wheel of a race car.
Anyway, it appears you are riding the fence in the following statement: “Instead, it is a simultaneous shortening of the inside leg coupled with a tipping of the lower leg.” While there are both simultaneous AND sequential movements that occur up and down the kinetic chain of movement, a kinesthetic priority as a turn initiating focus exists over other movements, higher up the chain that do move simultaneous with the feet. All movements that occur higher in the chain but simultaneous with the feet are simply anticipatory movements - anticipatory to the feet. Movements or kinesthesis that works through the kinetic chain relies on the muscular-skeletal construction of the human anatomy with which to provide the appropriate or “natural” timing of movements as they flow through. Attempts to manipulate this natural chain of movement “mid-chain” or in pieces and parts is what gets us into trouble. Think of the energy and force that travels or “flows” through the cord of a whip. Snap the wrist and watch the wave of energy and movement flow through the cord until it reaches the end where that flow of energy is released with a loud crack at the very end. Anything one would do to make changes halfway through the whip’s kinetic chain would result in a loss of energy traveling through the whip. These overly augmented movements with overly instigated timing that people use in attempts for correction or advancement are all too often miserably ill fated.
On a side note, I think when you use the terms “lateral separation”, you may want to clarify to the readership that you are referring to angulation. Everybody understands “rotary separation” as it is used very often but, “vertical separation”” (flexion, extension) and lateral separation” (angulation), are not very typically used other than the parenthesized form and therefore may be confused for something else such as lateral separation vs vertical separation of the feet in regards to stance width inputs. Just a thought and a product of finding your comments both interesting and agreeable as are quite a few from others in this thread.
When we create ground force reaction with our feet and skis, we have to keep our CoM to the front and to the inside of it as if we are surfing a wave of ground force reaction (GFR) that rolls in from the uphill and outside of each turn and, an alignment of forces analogous to a dolphin surfing the bow wake of a ship. How we do that is by managing the CoM to BoS relationship, moving the CoM over the BoS (like moving an imaginary joystick to get over the right or left shovel) and keeping the downward vector between the Com and BoS “equal and opposite” (equal force, opposite direction) to the upward vector of GFR. Our power, balance and control comes from matching the vectors of CoM/BoS and GFR whereby tipping the CoM/BoS vector “off axis” from the GFR vector using inclination in the direction of the turn only ever so slightly to provide a change in the direction of our momentum back and forth across the slope. While we can anticipate and predict some of the upcoming GFR vector in general using our visual of upcoming terrain, it is the “immediate” feedback or, “feel”, from the GFR itself to the feet specifically (not the hips) that we use to stay on top of it just like we would on a balance board. In terms of understanding what “skiing from the feet” is, think of skiing as being on a balance board where your ankles/feet have complete kinesthetic priority over all other possible movements and where all gross movement patterns above the ankles are nothing but indicators of being out of balance.
Lastly, it is clear that the PSIA’s new 5 fundamentals (separate from the 5 fundamental movements mentioned above) are, finally, all based on the ski itself, its input and output rather than focus on individual movement patterns and sectional concepts, indirect mid-chain instructions, upper body focus, etc., etc. An advancing skier needs to be made to understand what needs to happen to the ski itself and how it needs to interact with the snow surface such as tipping, fore/aft/left/right pressure control, engaging both skis equally except for outside pressure dominance, creating ground force reaction and learning the feel associated with these ski based inputs and outputs. Earlier used in reference to the foot and boot shell, think about the "contact pattern' between the base and edges of the ski with the surface below. For example: What is inside leg shortening actually used for in relation to the ski specifically? Tipping and turning? Really? We are deciding where and how much to turn by how much we shorten our inside leg? Is that what some of us are thinking when initiating a turn? "Hmmmm .... If I soften/lighten/shorten my inside leg by this much, I should make the next gate/tree by six inches." Or, is the inside leg simply allowing input from the inside ski which is receiving "direct" input by the foot/ankle?