New video

Ken,

Since I've criticized your technique, here's a link to a video of me.

http://www.skinnyski.com/tools/video...eos/mora2007-3

The first guy finishing (the 30 km race) was Bjorn Battdorf, the
second guy was Andy Schakel, and then me (bib 2001). There's gaps
between the skiers, so no need to sprint, but I'm certainly pushing to
finish fast (almost a sprint).

You and I have taken completely different routes to working on
technique. You have video taped your technique, analyzed it, and then
tried to make refinements. I applaud your efforts. It's certainly more
scientific than my method.

I simply watched the 1992 4x10 Olympic relay a million times,
imitated, skied, worked on balance(!), being smooth, and trying to
"feel" my way to better power. This was the route recommended to me by
a former national team member. (Basically, watch the video and
imitate.) Some other info is that I alpine skied as a kid, and have
been xc skiing about 15 years. I think this is the first video I've
see of myself skating on snow. What I'm saying is I don't video tape
myself (but I probably should).

Another difference was that I was trying to learn by doing technique
like the 4x10 video, and I _think_ you're trying to apply more
iconoclastic ideas that certain unusual movements should give more
power, speed, etc.

Jay

That video is nice because it shows three different (steady) tempos of
doing V2. Jay's seems closer to a tired man's sprint than an all-out
power chase to the line a la Ahlsgaard and Zorzi, but the basic
movements are identical to that of the others.

rm

"Bjorn A. Payne Diaz" wrote:

Ken,

Since I've criticized your technique, here's a link to a video of me.

http://www.skinnyski.com/tools/video...eos/mora2007-3

The first guy finishing (the 30 km race) was Bjorn Battdorf, the
second guy was Andy Schakel, and then me (bib 2001). There's gaps
between the skiers, so no need to sprint, but I'm certainly pushing to
finish fast (almost a sprint).

You and I have taken completely different routes to working on
technique. You have video taped your technique, analyzed it, and then
tried to make refinements. I applaud your efforts. It's certainly more
scientific than my method.

I simply watched the 1992 4x10 Olympic relay a million times,
imitated, skied, worked on balance(!), being smooth, and trying to
"feel" my way to better power. This was the route recommended to me by
a former national team member. (Basically, watch the video and
imitate.) Some other info is that I alpine skied as a kid, and have
been xc skiing about 15 years. I think this is the first video I've
see of myself skating on snow. What I'm saying is I don't video tape
myself (but I probably should).

Another difference was that I was trying to learn by doing technique
like the 4x10 video, and I _think_ you're trying to apply more
iconoclastic ideas that certain unusual movements should give more
power, speed, etc.

Jay

On Feb 12, 12:56 pm, "Bjorn A. Payne Diaz"
wrote:
Ken,

Since I've criticized your technique, here's a link to a video of me.

http://www.skinnyski.com/tools/video...ng/results/200...

The first guy finishing (the 30 km race) was Bjorn Battdorf, the
second guy was Andy Schakel, and then me (bib 2001). There's gaps
between the skiers, so no need to sprint, but I'm certainly pushing to
finish fast (almost a sprint).

You and I have taken completely different routes to working on
technique. You have video taped your technique, analyzed it, and then
tried to make refinements. I applaud your efforts. It's certainly more
scientific than my method.

I simply watched the 1992 4x10 Olympic relay a million times,
imitated, skied, worked on balance(!), being smooth, and trying to
"feel" my way to better power. This was the route recommended to me by
a former national team member. (Basically, watch the video and
imitate.) Some other info is that I alpine skied as a kid, and have
been xc skiing about 15 years. I think this is the first video I've
see of myself skating on snow. What I'm saying is I don't video tape
myself (but I probably should).

Another difference was that I was trying to learn by doing technique
like the 4x10 video, and I _think_ you're trying to apply more
iconoclastic ideas that certain unusual movements should give more
power, speed, etc.

Jay

Looks nice to me!

Question: why does the announcer feel he has to say "Minneapolis
MINNESOTA" (my emphasis). Aren't they in Minnesota? Is there more
than one Minneapolis in another state somewhere?

Why do government officials, broadcasters and others say USA, when it
used to be U.S. or United States, and there's only one?

"Camilo" wrote:

Looks nice to me!

Question: why does the announcer feel he has to say "Minneapolis
MINNESOTA" (my emphasis). Aren't they in Minnesota? Is there more
than one Minneapolis in another state somewhere?

Good going Jay
--
JT
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OK, here's two videos of me at our "local" place for downstate New
York -- Fahnestock Winter Park -- last weekend.

http://www.jt10000.com/images/special/jtv220070218.wmv
http://www.jt10000.com/images/special/jtv120070218.wmv

Any thoughts on technique? In the V2 I'm using less abdominal
compression than I'd thought so will work on that.
--
JT
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Jay -

You sure make it look easy.
http://www.skinnyski.com/tools/video...eos/mora2007-3

Here's some observations:
Legs
(1) set-down of foot underneath, in between the two hips.
(2) out-sweep push using muscles on side of leg starts soon after set-down
. . (unlike the first guy he seems to glide for a while before he starts
his leg-push.)
(3) follow-thru goes at least 15cm into the air, then recovery of foot is on
a smooth downward path.
(4) recovery of foot goes further inward than its sideways position at
set-down, so the out-sweep move starts before set-down.
. . (like in a Per Elofsson V2 skate video from World Cup race)

Hips
(1) hip-knee line stays fairly stable sideways, to transmit both out-sweep
push and torso side-tilt force.
(2) hips fairly high
. . (which seems different from side-views I've got of Christian Zorzi
doing V2 skate in the middle of a World Cup race -- He drops his hips lower,
like more emphasizing "Classic" double-poling aspect of V2)
(3) slight tilting of pelvis from side to side.

Poling:
(1) Looks like some "crunch" or "curling" in upper abdomen (not easy to see
in front view)
(2) Shoulders do not drop very much (5cm?) - (not a lot of "forward fall"
onto the poles?)
. . (I see Christian Zorsi's shoulders dropping like 15cm, Elofsson
dropping at least 10cm)
(3) Hands in fairly close to shoulders (sideways, though I can't see
front-back relationship clearly)
(4) Elbows winged out significantly.
(5) Lots of range-of-motion in the arms.
(6) Pole tips farther apart than the hands -- each pole is aimed slightly
outward.
. . (Pretty similar to front-view of Per Elofsson doing V2)

Upper body:
(1) Torso + shoulders tilt away from the leg-push, looks like about 10cm to
each side, for a total amplitude of about 20cm.
. . (Pretty similar to front-view of Per Elofsson doing V2)
(2) Slight rotation about vertical axis to face partly toward the aim of
each ski, like say 10 degrees toward each side, for a total rotational
amplitude of like 20 degrees.

Interpretive thoughts:
(a) Positive management of both "ends" of the leg-push force-pair: The leg
pushes the ski outward against the snow in one direction, and the mass of
the rest of the body moves in the other direction, with pretty "straight"
transmission between the two ends.
(b) If I'm right that Jay is putting less emphasis on poling and more on
leg-push than Zorzi . . . then ? Perhaps that's simply an appropriate
strategy for the flat terrain in Jay's finish, versus the moderate uphill of
Zorzi's video clip? Or maybe that just shows that World Cup racers are
different from the rest of us, and can exploit more back bend and more knee
bend?

Ken

Jay (Bjorn A. Payne Diaz) wrote
You and I have taken completely different routes to working on
technique. You have video taped your technique, analyzed it, and then
tried to make refinements. I applaud your efforts. It's certainly more
scientific than my method.

In addition to video, I've also been to camps, taken lessons, and paid for
personal coaching.

I think I am required to learn differently because I do not have a special
propulsive-motion-learning module in my brain which I know some other people
do have. Lately researchers in neurology been discovering that significant
percentages of the population have specific mental deficits -- but learn to
work around them by adapting other modules in their brain to sorta learn to
perform similar functions, though less quickly and accurately. I think
that's what I've been forced to do with both my cross-country and downhill
skiing motions.

I know that two of my backcountry downhill ski partners are wonderful skiers
in all snow conditions and terrain but have never taken a lesson. One of
them got interested in ski-skating a couple of years ago. I told him (like
most people who ask me) that there's some good instructors where he lives
(in Utah), so he should take lessons from them, not a theorist like me. But
he's cheap and learns lots of things without lessons and we were in France,
so one day at La Feclaz I gave him a couple of general concepts and three
drills to play with for his leg-push. Two years later we got together at
Mountain Dell during a lunch hour this January, and I watched him skate --
and all I could do was tell him all the things he was doing _right_ with his
legs and hips.

He swore he had taken not a single skiing lesson during those two years
(even though two of his local backcountry skiing friends who I also know
have taken skating lessons). His brain has a module which can take a two
concepts and three drills from me, and extrapolate those into sound leg-push
technique. He was skiing better than I look in my videos. (His pole-push
was terrible, but I had not told him anything about that -- so I did give
him a couple of concepts and some moves to try for that . . . Maybe I'll
check back in a couple of years.)

The reason I insist on getting videos taken of my cross-country skiing
motions is because personal videos were the critical breakthrough for me in
learning downhill skiing as an adult (starting at age 29). My subjective
perception of my body positions had been completely (embarrassingly)
different than from what I saw in my videos. Only after seeing myself on
video did I recognized that all those drills that were supposed to force me
into "facing down the hill" had been completely ineffective. Also in
downhill skiing I took lots of lessons from instructors at the best
lift-served ski resorts, and read lots of books about concepts and
scientific theory. And it all made sense: There was agreement on the core
theory (often counter-intuitive) -- and each time I aligned my video
performance with scientific theory, I soon noticed a further obvious
substantial improvement in my downhill skiing control.

When Sharon got me into cross-country skiing, I decided to focus on Classic.
While I was surprised that the coaches and books and articles didn't seem to
show a clear understanding of the physics, it only took about a year to
clarify my understanding of most of it. Again, alignment of my drills and
video with the physics resulted in quick obvious improvement in my
performance.

Skating technique was said by all the experts to be simpler than Classic, so
a couple of years ago I applied the same approach to Skating: lessons and
video and scientific analysis. Quick obvious improvements ... Not!

I simply watched the 1992 4x10 Olympic relay a million times,
imitated, skied, worked on balance(!), being smooth, and trying to
"feel" my way to better power. This was the route recommended to me by
a former national team member. (Basically, watch the video and
imitate.)

Of course my response is that very likely a successful "national team
member" has an excellent genetically-wired and early-childhood-developed
specialized brain module for learning propulsive bodily motions. My view is
that national XC ski team members have lots more than just excellent VO2max
engines. (Anyway copying another good skier really is a good way for lots
of people to learn.)

Some other info is that I alpine skied as a kid, and have
been xc skiing about 15 years.

I started ice skating when I was 8 years old. Never took a lesson. Learned
lots of moves from copying other people and practicing and figuring it out
for myself (crossovers, skating backwards), just free skating at an outdoor
rink, or me and my buddies shoveling off some local lake. My backward
skating was so good that each hockey team made me into a defense-man, even
though I'm not a large guy. And as soon as a coach on a higher-level hockey
team saw my skating in a game, I immediately got asked to try out for his
team. I went to hockey camp in Toronto, and the instructors had some
sessions on improving skating technique, and I had almost _no_ interest. I
figured I could do virtually anything I wanted on ice skates with complete
comfort and balance, so what was the point.

I think this is the first video I've see of myself skating on snow.
What I'm saying is I don't video tape myself (but I probably should).

I've found there's lots of pitfalls with video.

Another difference was that I was trying to learn by doing technique
like the 4x10 video, and I _think_ you're trying to apply more
iconoclastic ideas that certain unusual movements should give more
power, speed, etc.

Yes I'm looking for better techniques to give me some "edge" (mostly by
trying to show from physics that "iconoclastic" moves by World Cup racers
like Alsgaard + Belmondo + Carl Swenson + Kikkan Randall are _correct_,
although different from lots of simplistic American coaching concepts). I
know from watching so many riders easily pass me on big bicycling climbs in
the mountains, that "VO2max engine" is _not_ going to be my edge. Technique
did seem to work for me for racing Classic.

Also my graduate research and thesis was on the control of humanoid robot
motions, and long ago other people wrote scientific papers giving plausible
"robot-like" analysis of the physics and biomechanics of other human-like
propulsive motions. So I've felt like, "How hard could it be?" for analyzing
cross-country Skating.

But after about four years of trying to understand scientifically the
physics and biomechanics of skating, and trying to improve my own skating,
and getting coaching and shooting videos . . . I'm still finding myself
wrong about things -- still learning and trying new things.

And having lots of fun with it.

Ken

John -

I say leave those videos up on your website and we can tell people where to
look to see solid V1 and V2 technique by an advanced racer on a nice snow
day.
http://www.jt10000.com/images/special/jtv220070218.wmv
http://www.jt10000.com/images/special/jtv120070218.wmv

I'm going to try my usual detailed part-by-part theory-based analysis
because that's just me. Hopefully you or somebody can find some some points
of stimulus in it somewhere, hopefully some sense of how to relate them to a
useful focus and actionable mental images. (Maybe if we're lucky someone
gifted like Zach Caldwell will offer a deeper holistic perception.)

First some detailed observations . . . (then some "interpretive thoughts") .
.. .

Legs
(1a) V2: set-down of foot underneath, in between the two hips.
(1b) V1: set-down a little outside its hip.
(2) out-sweep push using muscles on side of leg starts soon after set-down:
I see the knee moving a substantial inward distance away from the
push-direction of the foot.
(3) recovery of foot is on a smooth low path.
(4) recovery of foot goes further inward than its sideways position at
set-down (more so in V2 than V1) -- sorta like starting the out-sweep move
"in the air" before set-down.
. . (like in a Per Elofsson V2 skate video from World Cup race)
(5) "forward knee drive" move (ankle flexion or "dorsi-flexion") move soon
after set-down: I'm seeing the knee forward vertically over the toe.
(6) some ankle extension (or "plantar flexion") in the final phase of the V2
push.
. . (not as much as I remember in some elite racer videos)

Hips
(1) pushing-side hip moves somewhat outward sideways relative to its knee
(5-10cm?). So the sideways hip-knee move is opposite to the sideways
knee-ankle move. Another way to say it is that the hip joint moves sideways
less far from the foot than the knee does.
. . (my memory of front views of elite racer videos doing V1 + V2 is that
hip moves away from the pushing foot at least as far as its knee: The knee
moves distinctly inward and downward, and the hip appears to "track" along
with it.)
(2) hips fairly high in V2
. . (which seems different from side-views I've got of Christian Zorzi
doing V2 skate in the middle of a World Cup race -- He drops his hips lower,
like more emphasizing "Classic" double-poling aspect of V2)
(4) I think I see a slight rotation of the pelvis about its vertical axis so
that the non-pushing-side hip moves forward relative to the pushing hip
(tricky to tell since the 90-degree side-views are only a brief glimpse) --
or at least the non-pushing-side hip is "holding even" with the other hip,
and not dropping back.
. . (which fits with what I remember of side-views of elite racers skating)

Poling:
(1) V2: Looks like not a lot of "crunch" or "curling" in upper abdomen (as
you said).
(2) V2: Shoulders do not drop very much (less than 5cm) -- not a lot of
"forward fall" onto the poles.
. . (I see Christian Zorsi's shoulders dropping like 15cm, Elofsson
dropping at least 10cm)
(3a) Hands not as close to to the chest in forward-backward direction as I
remember from elite racer videos of V2: Elbow bend at start of pole-push
often looks like greater than 90 degrees.
(5) Lots of range-of-motion in the arms, with extension of hands finishing
out behind hips.
(7) V1: Often the recovery-side hand starts its push more on its own side,
instead of first crossing significantly into the center of the chest.
. . (like maybe the pole-push overall is not "aimed" sideways as much as
Carl Swenson climbing a steeper hill)
(8) V1 the recovery side hand finishes way outside.
. . (reminds me of front-view video of Carl Swenson's V1)

Upper body:
(1a) Torso + shoulders tilt sideways somewhat away from the leg-push: V2
looks like about 5-8cm to
each side, for a total amplitude of about 10-15cm.
. . (A little less than I see Per Elofsson doing V2)
(1b) V1 looks like around 10cm tilt toward each side, for a total amplitude
of like 20cm.
. . (I see Carl Swenson's steeper V1 showing a total side-to-side amplitude
of shoulders relative to hips of around 30cm)
________________
Interpretive thoughts:

(A) Almost of the key moves and positional angles of the elite racers are
_there_ in your technique -- but with smaller range-of-motion distances than
in elite videos. Some ideas about that:
* Elite racers are just different from the rest of us, and your current
range-of-motion distances are simply what's appropriate for your muscles.
Conscously forcing the range-of-motion of a couple of your moves to be just
like some video of Carl Swenson is not going to make you faster like Carl --
just burn out a couple of muscles in the first five minutes of the race.
* Many of those muscles required for those moves are not used hardly at all
for sound effective expert _bicycle_ pedaling technique. So maybe they're
not getting enough specific aerobic endurance base and specific theshold
intensity development to push in "proportion" with your bicycling-specific
muscles. (I'm guessing you've been doing some non-bicycling specific
training in the summer and fall to develop a "forward knee drive" move so
close to elite angle.)

(B) Hip-Knee-Ankle relationship
[esp. Hips observation (1) above] I think having that sideways
hip-relative-to-knee move somewhat opposite to knee-relative-to-ankle move
in the first phase of the leg-push means that the skier's body mass (other
than in the pushing leg) is _not_ getting moved as fast or far away from the
foot pushing into the ground. By Newton's Third Law, every force needs
something to push _against_ (like the downward push on the bicycle pedal
pushes mainly "against" the gravity of the cyclists' body weight). The
sideways component of the skating leg force pushes mainly "against" the
"inertial" force of the skier's body mass, so if more of that mass doesn't
get moving as fast sideways ("kinetic energy"), there's not as much
effective leg-push force thru the ski into the ground.

So I think there's an opportunity to gain power by keeping the sideways
hip-knee relationship more _stable_ to transmit force better between lower
leg and upper body -- by an near-isometric contraction of the "hip
abduction" muscles to try to press the hip inward (or the knee outward,
whichever way you want to look at it) -- to prevent the hip from "naturally"
being "left behind" to the outside as the knee moves inward. [Hip Abduction:
yet another muscle function not trained much by bicycling.]

Transmitting force always works both ways, so that means more force against
the sideways inward knee-relative-to-ankle move -- so I'm guessing that move
is going to lose some range-of-motion. So instead of two larger-distance
opposing moves, you get one smaller-distance move and one static
tranmission -- with higher force intensities -- and overall the net
contribution of Work is larger. (Which illustrates another big trap with
video analysis: It shows the distances and angles, but not the forces -- so
the range-of-motion Distance matches the elite racer videos, but the Force
is completely different.)

(C) Abdominal "crunch" and "Forward fall" in the pole-push.
The obvious idea is that if the elbows started more bent and the hands
closer into the chest, then the arms could hold more stable to _transmit_
abdominal-muscle and gravitational forces during the first phase of the
pole-push. The tricky consequence is that to _repeat_ that kind of pushing
down requires raising the weight of the torso and shoulders back _up_ again:
There's no free lunch. For adominal-crunch this implies that the
Back-Extension muscles must do active lifting work. Recovering from the
"forward fall" aspect requires the back-extension muscles to at least
statically _transmit_ substantial lifting forces from the hip-extension
muscles. [Back Extension: yet another muscle function not trained by
bicycling.] Anybody ever heard of serious racers getting back injuries?

My theory is that if your back-extension does not have enough specific
aerobic endurance base and specific threshold intensity development from
summer+fall training -- then you can consciously believe and decide to use
lots more abdominal crunch and forward fall, but your unconscious
neuro-muscular control is going to find a way to block it and reduce it --
to do its job to try to protect those muscles against injury. So the minute
you turn your conscious attention to something else (like the race
situation), I bet those good "crunch" and "fall" moves are going to shrink
right back down to their old way.

(I have to remember all those good suggestions I've gotten from previous
videos and personal coaching . . . How easy it was to execute them in
isolated practice . . . Then how quickly and often I reverted to my old
ways. My conclusion is that only a carefully designed long-term
multi-pronged approach is going to result in a sustainable increase in power
and speed. The job of a gifted coach, not a theorist.)

Ken

Any thoughts on technique? In the V2 I'm using less abdominal
compression than I'd thought so will work on that.
--
JT

JT,

Nice shots of you. On the V1, I noticed that you are "C" curving. In
other words, your upper body goes to the left when you are poling
left, but your hips stay towards the middle, which makes a "C" curve
in your body.

The way to correct this is to shift the hips more to the outside so
that they are over the ski, allowing for greater glide on each stroke
and a flatter ski.

Your upper body and ab compression look pretty good.

Greg Fangel