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舊 2010-02-04, 17:19   #1
eLeung
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PSIA - Pivot Slip Leapers

It may be a new version of Pivot Slip, enjoy! :)

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舊 2010-02-05, 04:15   #2
B2L2
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Leapers focus on the hop. i.e. you do a small hop to get skies off snow and do the init turn in the air.

So combining this with Pivot Slip, you then get the pivot slip leapers. :)

eLeung, here are all the videos from PSIA-RM (rocky mountain), if you haven't watched yet.
http://www.vimeo.com/psiarm/videos

- Brian
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舊 2010-02-05, 13:38   #3
eLeung
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eLeung, here are all the videos from PSIA-RM (rocky mountain), if you haven't watched yet.
http://www.vimeo.com/psiarm/videos
Wow! There are many video clips. Thanks!;)
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舊 2010-02-05, 23:50   #4
B2L2
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eLeung, enjoy then. The leaper/hop drills are there to promote quick and direct transition. By the end of the practice, one should reduce the hop and maintain snow contact. :)

- Brian
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舊 2010-02-08, 23:13   #5
eLeung
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eLeung, enjoy then. The leaper/hop drills are there to promote quick and direct transition. By the end of the practice, one should reduce the hop and maintain snow contact. :)

- Brian
Thanks, Brian, for your further explanation. :)
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舊 2013-02-26, 05:49   #6
Mike
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Here is the "Pivot Slips" without the leapers



You face down the hill with your hips and shoulders, while you rotate your femurs in your hip sockets. It's worth learning to do the Pivot slips, because rotating those legs independently of the upper body will help you maintain your balance as you ski. If you can't face down the hill with your upper body as your legs turn left and right, you will travel left and right, and the pivot slip fails.

You also have to manage the movement of that inside ski so it doesn't get hooked up and in the way, blocking the general pivoting of both feet. If the inside ski gets in the way, you travel right or left ... pivot slip fails.

You have to stay balanced in the right spot above your skis. You have to keep your COM moving down the hill along with your skis.

For a successful pivot slip, you need to be able to maintain just enough edge angle between the skis and the snow to provide enough grip so you slip down the hill at constant speed without making a face plant.
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舊 2013-02-27, 02:12   #7
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Excellent demo video and it is super hard to perform exactly the way he is showing. The slower you are, the harder to get this right.
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舊 2013-02-27, 10:41   #8
eLeung
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Excellent demo video and it is super hard to perform exactly the way he is showing. The slower you are, the harder to get this right.
Hi Brian, long time no chat :-) Wishing you a happy and healthy Year of the Snake! I am sure you will have nice skiing with Fish and your local gang. I really want to come but...

I totally agree that it is very hard to perform Pivot Slip. Could you share your experience with me how to practice this drill and what are the major benefits?
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舊 2013-02-27, 11:01   #9
Mike
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I totally agree that it is very hard to perform Pivot Slip. Could you share your experience with me how to practice this drill and what are the major benefits?
As explained by Bob Barnes in another ski forum,
I quote:
"Pivot Slips" are a useful and versatile exercise on skis that develops several important skills and sensations. First and most obvious, perhaps, is the rotation of the legs (femurs) in the hip sockets that is critically important in virtually all skiing maneuvers, from pure-carved arcs to hockey stops. Without this skill, skiers invariably rely on upper body exertions ("rotation" or "counter-rotation") and/or powerful blocking pole plants whenever they need to twist their skis. Upper body movements can twist or pivot skis only, causing skidding, and cannot be used to guide the skis or shape turns precisely. Without femur rotation (as with a fused hip), skiing as we know it is not possible at all. Beyond the obvious rotary effects, femur rotation is involved in edging movements as well.

Perhaps even more importantly, Pivot Slips help develop the feel for the edge release that marks the transition in offensive turns--again, whether pure-carved or brushed and guided. Such turns begin (and, if linked, end) in what I call "neutral," which is an attitude that is well-defined by Pivot Slips. The entire maneuver takes place in "neutral," on slipping skis with edges released. There should be no edge set, and no attempt to slow the slip at any point in the maneuver.

It's not the easiest of exercises, by any means. It is commonly used as one of several skill and discipline tasks for Full Certified instructor exams. Many people who "think" they're doing Pivot Slips are not!

Pivot Slips highlight the "release and guide the tips downhill, into the turn" initiation of modern, offensive turns. Perhaps the most common error when attempting them is the tendency to set the edge of the downhill ski, slowing or even stopping the slip, and then "pushing off" from the platform of that ski--pushing and twisting the uphill ski tail uphill, rather than guiding the downhill tip down the hill.

Fore-aft balance is critical in Pivot Slips. If it isn't just right, the skis will not slip directly down the fall line, and the pivot point will not fall directly under the foot, as in the animation above. It's a great way, therefore, to find a modern, neutral stance.

It's also effective at finding your optimal "ready" athletic stance for skiing--both vertically and stance-width-wise. Too narrow a stance compromises the power of the leg rotation involved (a locked-together stance makes it impossible). Too wide a stance, while powerful, creates problems with fore-aft balance, as one foot will be weighted forward and the other aft. A stance either too tall (knees and hips extended, femurs upright) or too short (knees and hips flexed) reduces the range of rotation available in the hip sockets.

Finally, while it hardly looks like an "edging drill," Pivot Slips develop the highly-refined sense of subtle edge control involved in the edge release and transition between turns. Learning to let go ("release") and maintain balance on released edges is critical in modern turns.

There are two ways to release a ski's edge: lift it off the snow (or at least, lighten it sufficiently), or reduce its edge angle until it lets go. Pivot Slips involve entirely the latter!
Nor is there a "down" move that might be associated with increasing the edge angle--because the skis slip continuously in this exercise."
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舊 2013-02-27, 20:34   #10
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I totally agree that it is very hard to perform Pivot Slip. Could you share your experience with me how to practice this drill and what are the major benefits?
Glad to hear other people saying it's hard.
My so-called "pivot slips" and "pivot slip leapers" were all over the place and came out totally wrong. I always thought that's me being so stupid that I couldn't get it right.
So may be it's not as easy as it looks and there are other people who can't do it either... that's reassuring.
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舊 2013-02-28, 03:57   #11
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Hi Brian, long time no chat :-) Wishing you a happy and healthy Year of the Snake! I am sure you will have nice skiing with Fish and your local gang. I really want to come but...

I totally agree that it is very hard to perform Pivot Slip. Could you share your experience with me how to practice this drill and what are the major benefits?
Hey eLeung, thanks and same wish for you. Yes, we were with Fish last Sunday and have a nice day. We will ski together for a few more days.

Mike's quote explained everything. For me, the toughness come in many areas:

1) leg rotation (femurs) in the hip sockets, this is an action that CSIA promotes. When doing this exercise, I then realize how little I could do that. Keeping knees bend is important in order to do this right.
(Bob's probably right that bending too much could also limit the motion, but I will have to experiment that too)
2) Very balanced stance in order to release the edge. Sometime, leaning forward down the hill is almost required.

For benefits from this exercise, for me there are many as well:

1) able to experience a cool way to create edge biomechanically. Rotating your leg in the hop sockets are using bigger leg muscles, however, we don't use this muscles a lot even as intermediate skiers, practice, practice, practice.
2) practice edge release, important step to do early edge release before fall line.
3) stable upper body, important step for short turns.
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舊 2013-02-28, 05:52   #12
Mike
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Mike's quote explained everything. For me, the toughness come in many areas:

1) leg rotation (femurs) in the hip sockets, this is an action that CSIA promotes. When doing this exercise, I then realize how little I could do that. Keeping knees bend is important in order to do this right.
(Bob's probably right that bending too much could also limit the motion, but I will have to experiment that too)
2) Very balanced stance in order to release the edge. Sometime, leaning forward down the hill is almost required.

For benefits from this exercise, for me there are many as well:

1) able to experience a cool way to create edge biomechanically. Rotating your leg in the hop sockets are using bigger leg muscles, however, we don't use this muscles a lot even as intermediate skiers, practice, practice, practice.
2) practice edge release, important step to do early edge release before fall line.
3) stable upper body, important step for short turns.
I have always been taught to face down the fall-line with my hip and shoulder and have a quiet upper body (also refer to http://hkssa.net/showthread.php?t=40009 ). It will be difficult to turn without rotating your femurs in your hip sockets..
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舊 2013-02-28, 06:03   #13
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Good for you, Mike.

Another thing is the range of the leg rotation. In my regular skiing, leg rotation was there, but very soon I "think" I'm hitting the limit. In fact it is my stance that "limited" my range of motion, which then triggered whole bunch of problems.

Looking at the demo above, the range of motion is there with the proper pose. That's why this practice is important for me.
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舊 2013-02-28, 09:22   #14
Mike
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In fact it is my stance that "limited" my range of motion, which then triggered whole bunch of problems.
Brian, what do you think is the problem with your "stance"? Too far apart?
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舊 2013-02-28, 10:21   #15
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Brian, what do you think is the problem with your "stance"? Too far apart?
Not enough bending of the 3 joints. When you stand pretty tall, doing leg rotation is not going to create much edging. It creates leg pivoting, but not much edging.

If you have enough bending particular in the knees (look at the video again), while leg rotates, it creates the edging we want.

What makes this edging interesting. :) We are creating edge angle without leaning much into the turn and the skies aren't far away from your body.
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