what's here

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Legs + Hips

what's here

ankle flexion

also called "dorsal flexion".

function: pull the toes up toward the hip.

geometry: foot rotates about a roughly horizontal side-to-side axis through ankle joint, so the toes move upward toward the hip joint.

video: see "more info" links below.

anatomical: shin, a.k.a. tibias, tibias anterior. (see ExRx links below).

sources of more info:

propulsive uses:

ankle extension

also called "plantar flexion".

function: push the toes down away from the hip.

geometry: foot rotates about a roughly horizontal side-to-side axis through ankle joint, so the toes move downward away from the hip joint.

video: see "more info" links below.

anatomical: calf, a.k.a. gastrocnemius and soleus. (see ExRx links below).

sources of more info:

propulsive uses:

ankle pronation

also called "eversion of the foot".

function: move the foot outward relative to the ankle, so sole of the foot faces more outward. Another way to see it is that the ankle "falls" toward the inside relative to a plane containing the heel, toe, and hip.

geometry: foot rotates about a roughly horizontal front-back axis through ankle joint, in the sense that the foot moves outward.

video: [ to be added ]

anatomical: (see ExRx links below).

sources of more info:

propulsive uses:

ankle supination

also called "inversion of the foot".

function: move the foot inward relative to the ankle, so sole of the foot faces more inward. Another way to see it is that the ankle moves toward the outside relative to a plane containing the heel, toe, and hip.

geometry: foot rotates about a roughly horizontal front-back axis through ankle joint, in the sense that the foot moves inward.

video: [ to be added ]

anatomical: (see ExRx links below).

sources of more info:

propulsive uses:

lateral ankle rotation

function: push the front of the foot sideways-outward (away from the other leg) relative to the overall leg.

geometry: the foot is rotated about a roughly vertical axis through the ankle joint, in the sense that the front of the foot moves away from the other leg.

propulsive use:

  • [ inline ] on inline skates, this move can add range-of-motion to end of the Phase 3b push, during the brief time while the skate has only one wheel (the front wheel) in contact with the ground.

  • see leg-in-air-behind-outward function.

medial ankle rotation

function: push the front of the foot sideways-inward (toward the other leg) relative to the overall leg.

geometry: the foot is rotated about a roughly vertical axis through the ankle joint, in the sense that the front of the foot moves toward the other leg.

propulsive use:

knee flexion

function: move the lower leg backward relative to the upper leg.

geometry: lower leg is rotated about a roughly horizontal side-side axis through knee joint, in the sense that the foot moves backward.

video: see "more info" links below.

anatomical: hamstring (see ExRx links below).

sources of more info:

propulsive uses:

knee extension

function: move the lower leg forward relative to the upper leg (like kicking a ball).

geometry: lower leg is rotated about a roughly horizontal side-side axis through knee joint, in the sense that the foot moves forward.

video: see "more info" links below.

anatomical: quadriceps (see ExRx links below).

sources of more info:

propulsive uses:

medial hip rotation (or "inward-hip-leg-rotation")

function and geometry: leg rotates from the hip around the longitudinal axis of the upper leg bone (femur), so the knee moves toward the inside (toward the center-line of the body).

video: [ to be added ]

anatomical: tensor fasciae latae, gluteus minimus (see ExRx links below).

sources of more info:

Hip Articulations (on ExRx)

propulsive uses:

skating leg push

more

"inward knee roll" is just a simultaneous combination of inward-hip-leg-rotation with hip-adduction.

lateral hip rotation (or "outward-hip-leg-rotation")

function and geometry: leg rotates from the hip around the longitudinal axis of the upper leg bone (femur), so the knee moves toward the outside (away from the center-line of the body).

video: [ to be added ]

anatomical: ? gemellus, obturator, quadratus ? (see "more info" links below).

sources of more info:

propulsive uses:

more:

"outward knee roll" is just a simultaneous combination of outward-hip-leg-rotation with hip-abduction.

hip flexion

function: move the entire leg from the hip joint, so the knee and foot move forward.

geometry: leg rotates from a (roughly) side-to-side horizontal axis through the hip joint, in the sense that moves the knee and foot forward.

anatomical: iliopsoas, etc. (see "more info" links below).

sources of more info:

propulsive uses:

hip extension

function: move the entire leg from the hip joint, so the knee and foot move backward.

geometry: leg rotates from a (roughly) side-to-side horizontal axis through the hip joint, in the sense that moves the knee and foot backward.

anatomical: gluteus maximus. (see "more info" links below).

sources of more info:

propulsive uses:

hip abduction

function: move the entire leg from the hip joint, so the knee and foot move out toward the side.

geometry: leg rotates from a (roughly) front-back horizontal axis through the hip joint, in the sense that moves the foot outward away from the other leg.

video: see ExRx links below.

anatomical: gluteus medius, gluteus minimus (see ExRx links below).

sources of more info:

propulsive uses:

supportive uses:

  • weight-transfer in classic striding

hip adduction

function: move the entire leg from the hip joint, so the knee and foot move in toward the other leg.

geometry: leg rotates from a (roughly) front-back horizontal axis through the hip joint, in the sense that moves the foot inward toward the other leg.

video: see ExRx links below.

anatomical muscles: adductors, etc. (see ExRx links below).

sources of more info:

propulsive uses:

supportive uses:

  • weight-transfer in classic striding

lumbar spinal rotation (or "forward-pelvis-rotation")

sometimes also called "forward-hip-rotation")

function and geometry: From a roughly vertical axis in the abdominal or lumbar area, the pelvis + hips rotate opposite to the thorax + rib cage.

Normally this is described as moving the thorax + rib cage relative to the pelvis + hips held fixed. But it can also be described the other way: rotating the pelvis + hips relative to the thorax + rib cage held fixed. Or with the thorax + rib cage also rotating, in the opposite sense. It's the second or third way that work in skating.

From the perspective of the hip joint of the currently pushing leg, as the pelvis + hips rotate about a roughly vertical axis, the other non-pushing hip joint moves forward, and that's why some of us like to call this move "forward hip rotation".

Though it could be more accurate to call it "forward hips rotation", since it's the pair of hips that rotates, and the rotation is about the axis of the spine, not about any axis through any hip joint.

Another mental image is to think of this move as making a forward step from high underneath the rib cage.

Of course, it would also be possible to rotate the hips vertically in the other direction, so the non-pushing hip moved backward relative to the currently pushing hip. Such a "backward hip rotation" move would be negative for forward propulsion, so it is not included in this list of skating moves.

Actually this "backward hip rotation" move is not unusual in skaters, especially ski-skaters who have been taught the "Nose-Knees-Toes" concept. Although it is not required by the NKT concept, this backward hip move is the simplest way to execute NKT.

video: see ExRx link below.

anatomical: ?? (see "more info" links below).

sources of more info:

propulsive uses:

Abdomen + Torso

what's here

abdominal flexion

also called lumbar or thoracic spine flexion

function: change the bend of the spine so it has overall move forward curvature.

So if the spine started in a straight configuration, this flexion move would tend to bend it forward.

video: see ExRx link below.

anatomical: rectus abdominis, etc. (see "more info" links below).

sources of more info:

propulsive uses:

  • classic striding leg push
  • double-poling pole push

back extension

also called lumbar or thoracic spine extension

function: change the forward bend of the spine so it has overall less forward curvature.

(or "hyperextension" would be to bend the spine in a more backward direction)

So if the spine started in a forward-bend configuration, this extension move would tend to straighten it up.

The move of stopping the falling and then raising the mass of upper body applies beneficial reactive down-force thru the leg

video: see ExRx link below.

anatomical: erector spinae, etc. (see "more info" links below).

sources of more info:

propulsive uses:

  • upper body reactive-down force for Skating with No Poles.
  • recovery from pole-push, and gain of gravitational potential energy for next pole-push in V1 skate, V2 skate, and Open Field Skate.
  • recovery from pole-push, and gain of gravitational potential energy for next pole-push in classic striding and double-poling.

[ to be added ]

abdomen-torso side-swing

includes "lateral flexion of the spine" or "abduction of the spine".

propulsive uses:

  • for reactive side-force in skating.

[ more to be added ]

chest-shoulder side-swing

perhaps another variation on "lateral flexion of the spine" or "abduction of the spine".

for reactive side force

 (? perhaps distinct from the lower abdoment-torso move ?)

propulsive uses:

  • for reactive side-force in skating.

[ more to be added ]

 

Shoulders + Arms

full-arm-from-shoulder inward side-swing

side-swing of entire arm from shoulder

propulsive uses:

  • for reactive side-force in skating.

[ more to be added ]

full-arm-from-shoulder outward side-swing

side-swing of entire arm from shoulder

propulsive uses:

  • for reactive side-force in skating.

[ more to be added ]

forearm-from-elbow inward side-swing

swing of lower arm from elbow

(perhaps distinct from side-swing of entire arm from shoulder)

propulsive uses:

  • for reactive side-force in skating.

[ more to be added ]

forearm-from-elbow outward side-swing

swing of lower arm from elbow

(perhaps distinct from side-swing of entire arm from shoulder)

propulsive uses:

  • for reactive side-force in skating.

[ more to be added ]

 

more . . .

 

see also

Skating No Poles | back to Top