older ideas -- focused on Ski Skating in cross country skiing
what's here
- - Three Big Problems
- - Hills different from Flats
- - Spread load to More Muscles
- - Assist weak muscles + zones
- - Supporting moves | Don'ts
- - the Steeper the Hill . . .
- - Concepts + Perceptions versus Physics + Video
see also

[ under construction ]
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Handling the hills is the biggest deterrent to enjoying skating for most
cross country skiers: Skiing fast and gliding long on the
flats is the fun part. Climbing up a hill is just a struggle, and
even after going over the top, it can leave our legs too burning and tired
to enjoy the next section of long gliding on the flats.
What can be done to survive the hills well enough so we can
enjoy the rest of our skating?
The question is:
Slow -- How to skate up a hill slowly?
Here we analyze this problem from the perspective of biomechanics and
physics, and propose some solutions.
The big problems
The three big problems in skating up a substantial hill are:
(A1) how to keep the skating "magic" going -- that
combination of glide with pushing out to the side -- which is the
only way to utilize some of the skating muscles.
-
(B) how to stay away from the low-repetition peak-force strength
"stress injury zone" for specific muscles.
-
(C) skating up hills with poles effectively is perhaps the most
complicated mode of human-muscle-powered propulsion. How to
coordinate all the moves? How to learn them?
Gearing
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(E) Skating Ski: The "gear ratio" of the skating ski is
mostly determined the angle it is aimed out to the side: The
lower the speed, the larger the angle out to the side. The
higher the speed, the closer the ski points to forward.
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(F) Poling: The "gear ratio" of the pole is mostly
determined by its angle between vertical and backward: The
lower the speed, the more the pole is angled down toward the back.
The higher the speed, the closer the pole starts to vertical.
Physical Efficiency
Different from ski skating on Flats
Skating on the flats or up a gentle hill is:
-
Not subject to Principle D -- so moving the upper body up and
down to generate forward motion is often an effective approach.
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"Gear ratio" for ski angle makes getting forward less important.
At the higher speeds on the flats, the skis are aimed more forward,
so the push is directed more out toward the
side, with the line of force is more in toward the center, less
forward -- so there is less benefit to positioning the skier's
center-of-mass more forward.
-
"Gear ratio" for pole angle makes getting the shoulders up high
more important. At the higher speeds on the flats, the most
effective pole-push angle is more vertical.
-
Less need on the flats to worry about Principle A1 -- keeping
the glide going (except in slow snow or headwind). And less
problem with Principle B -- getting into high-peak-force
low-velocity stress zone (because not fighting to raise full body
weight against gravity). So less need to worry about
"low-power spots", like the pole-recovery phase in V2 skate
and Open Field Skate.
Therefore:
-
V1 ("offset", "paddle-dance") and
Single-Poling Skate ("coaches skate", "herringbone skate"), is a more effective technique for
climbing steep hills. While V2 ("1-skate", "double-dance") is
often better for gentle and flat terrain.
Because flat terrain permits the full and
efficient use of vertical up-and-down motion of the legs and upper
body to drive the pole-push -- and V2 has more pole-pushes than V1.
And flat terrain is forgiving of the "low-power" pole-recovery
period in the V2 stroke cycle, where on a steep hill V2 would either
stall out and lose the "magic" in the pole-recovery phase or require
high-stress peak forces to keep it going.
-
Steep V1 skate focuses on optimal leg-push, and compromises on
the pole-push. Single-Poling Skate simplifies the poling to
focus on leg-push. But gentle V2 focuses on optimal pole-push power.
-
Steep V1 uses lots of sideways motion of the upper body
to assist the leg-push. While gentle V2 uses lots of vertical motion of the upper body to assist the pole-push.
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Steep V1 and Single-Poling Skate use little vertical upper body motion (perhaps
V1 has some "chest crunch" during -- or before -- the start of the
pole-push). While gentle V2 uses little sideways upper
body motion (perhaps a turn toward the new ski during -- or
after -- the end of the pole-push).
The physically optimal poling motion is to align
the handle and tip of both poles straight with the skier's overall
forward motion direction, and push both poles back straight in the
skier's overall forward motion direction. (Not with the poles
or the push aligned with angle of the current ski.)
In V2 poling, the idea is to focus on that
physically optimal motion -- and to achieve that focus, to limit
shoulder-torso rotation or tilting motions in V2 (even if those could
help the leg-push). But in V1 the poling motion is a
deliberate compromise. Especially the recovery-side pole-push is
sub-optimal -- the hand starts low and it pushes toward the side.
V2 uses many muscles throughout the body to drive
the pole-push. But steep V1 uses mainly just the arms,
together with an "untwisting" of the shoulders, assisted
with a little "chest crunch" (but not "waist crunch" or "hip crunch"
with the lower abdominals).
In gentle V2 the idea is to fall forward
onto the poles. But in steep V1 the idea is more to stay
forward -- when there's any forward fall, it's to fall further
forward.
Forward hips is a temporary dynamic thing in V2.
But in steep V1, forward hips is closer to a static position
to be maintained.
Though even in V2, the idea is to drop the hips
down only as far as you have the strength to raise the hips
all the way up and forward to aggressively fall forward
to start the next stroke. Lots of skiers have the flaw
of their butt "getting stuck" sitting back there "down in the
bucket" -- in V2 as well as V1.
And even in V2, it does not help much to drop the
butt, if you do not have the strength in all of the abdominal,
trunk, shoulder, and arm muscles to transmit the butt-drop
force into the pole-push.
Variations on techniques
Even if there were one optimal technique for climbing up a hill, that
does not mean it's smart to use exactly that technique in all skiing
situations. Sometimes it's smart to practice a technique that
partly contradicts some of the principles of physics and biomechanics on
this website. There are several reasons to use and practice
variations:
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Simplified technique to manage the complexity while still
learning.
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Controlled isolation of weaker muscles in training
situations -- to strengthen them and raise their
sustained-power-delivery capacity.
-
Avoid weaknesses in fun and race-performance situations.
This is why most of us cannot simply copy the elite racers --
because we have not trained some of those special muscles all year
long.
-
Exploit our strengths in fun and race-performance situations.
Each of us has different strengths from other sports:
Like think of bicyclists versus inline-skaters versus kayakers.
-
Focus -- Prioritize the moves selected in fun and race-performance
situations: Focus on the moves that deliver the most
sustained-power benefit and ignore the others -- so we don't get
overwhelmed by the complexity.
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Which technique
-
Single-Poling Skate and V1 are better than V2 for steeper hills
-
V1 technique is the primary technique discussed on this
page, but most of the ideas are applicable to Single-Poling Skate.
Spread the lactate load across more muscles -- is the main answer to
problem (A).
direct leg-push
more muscles for the direct leg-push:
This is the key move for biomechanical Hip-Knee-Ankle
configuration -- its objective it to move the ankle joint back
behind the knee joint and hip joint -- just before the main
leg-push with the big strong knee-extensor (quadriceps) and
hip-extensor (gluteus maximus) muscles.
The biomechanics of getting intense force out of the main
leg-push just seems to work better if the ankle is strongly flexed,
so the ankle joint starts behind the hip and knee joints. At the
start of the skating leg-push when the next foot is first set down,
the hip joint is low and behind the ankle-joint. So it requires a
special move to bring the hip joint up and forward.
To me it's like standing up and forward on a bicycle, to pedal up
a hill without shifting down into a lower gear. (The problem with
skating on snow is that it does not provide us with enough "gearing"
options on the low end of the speed range.)
The mental image of flexing the ankle does not seem to helpful
for lots of people. What often works better is to think of driving
the knee down and forward. Or you might find it's more
helpful to try thinking about driving the heel back and down.
With good skating form, "it's all relative" --
since the hip, knee, and ankle joints are all roughly in a plane
with the current aiming of the pushing ski.
Do not bend the knee any further during this move, since flexing
the knee joint will move the hip joint lower and further back, just
the opposite of good biomechanics for the strongest leg-push needed
to raise your full body weight up the hill.
Too many well-meaning skate coaches preach to
"bend the knee more", when the true secret of hill-climbing is to
bend the ankle more.
Shin muscle -- getting the Knee-drive Hip-drive move is partly
mental image and balance -- but it's also about developing a
specific muscle -- the shin muscle on the front of the lower leg is
what must do the actual work of flexing the ankle.
It takes a few weeks to develop the specific
strength and specific endurance needed to develop that muscle. So
don't overdo it at first with this new move, or you can strain it.
Give it a careful program of progressive training, and time to
develop.
-
Hip abduction -- push the whole leg out to the side from the hip, using the
hip abductor muscles ("gluteus medius").
-
Toe-push -- using the calf muscle. But only at the very
end of the skate-push.
Many coaches warn that it's usually bad to
think consciously about toe-push. Some say that if you consciously
focus on strong forward-ankle-flex, your ankle will unconsciously
make the right un-flex push at the right time.
Ideas to play with: (a) Aim the toe-push out
toward the side, not back down the hill; (b) Slice the ski forward
as you make the toe-push; (c) Set the other ski down into the snow
before starting the toe-push.
weight-shift / reactive side-force
more muscles to help with weight-shift / reactive side-force:
- Shoulder-Torso swing -- rotate and tilt the weight of the chest and shoulders
sideways to generate reactive side-force.
Both the starting and the
stopping of the shoulder-torso-swing move can be timed to help the
leg-push.
- Sideways Arm-swing on the recovery-side.
The winning elite racers have a surprising move
with one arm. The recovery move of the arm on the
pole-recovery-side starts outward (and also upward).
Perhaps this could be synchronized with the second phase of the
hang-side leg-push to generate a small reactive side-force to help
that leg-push. But it's main purpose is to get into position
for ...
Then the recovery-side arm makes a sharp move
inward during the recovery-side leg-push. This generates a
reactive side-force that helps the recovery-side leg-push (which
often is in much need of help).
Transmission of reactive side-force
[?? to be added ]
move specific body-parts against gravity + air-resistance
[?? to be added ]
forward step (with hip flexor muscle)
forward-hip-rotation (with pelvic rotator muscle)
hip-forward (with shin muscle)
[?? to be added ]
pole-push
more muscles to help the pole-push:
- Shoulder "untwist" to help drive the hang-side pole-push in V1
skate.
- Chest pre-Crunch before the start of the pole-push in V1
skate (?)
There's a trade-off on this, because while it
spreads the load to more muscles, it violates Principle D of not
lifting the same body parts (head and shoulders) through the same
vertical motion range twice -- in the "Back Lift" move below.
So do not overdo this move, and use even less of it on steeper
hills.
Note that the elite racers actually make most of
their chest crunch before the start of the pole-push.
And some duck their head. That way the weight of the head and
shoulders gets raised no more extra height than necessary, to
minimize the violation of Principle D.
Another way to think of this move is that the
sudden dropping of the weight of the chest and shoulders downward
generates a reactive force upward (by Newton's Third Law), which
helps lift the weight of the legs and butt up the hill -- or at
least helps "lock in" any vertical gain from lifting the legs and
hips during the recovery-side leg-push.
Warning: Trying to get more out of this move
leads to dropping the butt (a bad idea on a steep hill).
Instead keep all the crunch high in the chest.
- Back Lift extension -- needed to get into position for the Chest
pre-Crunch
Warning: Thinking consciously about lifting
the shoulders (using the back extension muscles) can distract from
sideways torso rotation (and other moves) that is necessary maintain
side-glide. So it leads to stalling on the recovery-side, or
nearly stalling. Lose the side-glide and you lose the magic of
skating -- might as well just do classic herringbone.
Warning: Thinking consciously about lifting
part of the upper body can lead to thinking about direct lifting of
the butt and whole upper body, by using the big leg muscles during
the recovery-side skate-push. There are several dangers from
this thought: (a) distracts leg muscles from pushing out to
the side; (b) raises body too much upward and not enough forward;
(c) makes it feel OK to have already allowed the butt to have
dropped back and down.
Transmission of pole-push forces
[?? to be added ]
Assist the weaker muscles and avoid stress
zones
Pair with other muscles
Assist weaker muscles by pairing them with other muscles.
- On the poling side of V1, we use the poling arm muscles to
assist the weaker hip abductor muscles during the first phase of the
skate-push.
- On the pole-recovery side of V1, we use the reactive side-force
from stopping the previous torso-swing move to assist the first
phase of the skate-push. And we also use the assistance of the
reactive side-force from immediately starting the next
torso-swing more back toward the poling side.
- In herringbone skate, we use the single-pole-push on each side
to directly assist the skate-push on each side.
Momentum to assist
Assist weaker muscles with momentum (or "kinetic energy") from
previous work by other muscles.
- On the pole-recovery side of V1, we use the greater combined
kinetic energy from the poling-side skate-push and pole-push to
help the skate-push on the pole-recovery side.
Avoid weak sections in range of motion
Use muscles in the strongest section of their range of
motion. Avoid putting peak forces on muscles and joints in
the weak sections of their range of motion -- since this results
in rapid fatigue and pain -- even injury.
Avoid peak forces from stopped position
Avoid requiring a muscle to apply a high peak force from a
stopped position (or a very slow speed).
- This is why V2 (even "quick V2") is not effective up steeper hills:
The skier's motion slows down too much in the pole-recovery
phase, and that requires starting the next pole-push from a
stopped position (or almost). Or to avoid stopping, it
requires a peak-force intensity in the pole-push and
leg-push which gets into low-rep / peak-force stress zone --
in order to carry enough momentum (or "kinetic energy") thru
the pole-recovery phase.
- There can also be a problem with "stalling" on the
pole-recovery side of V1 when the hill gets too steep.
That's why at some grade of steepness, many skiers give up
on V1 and switch to "herringbone skate".
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