Alpine Movement Analysis
Ideal Outcomes
Watch the two videos below. While each skier will look different you will notice that each skier has:
Round and symmetrical turn shape.
Short and uninterrupted turn connection.
Consistent speed.
Next, we’ll look at the skills that produce these outcomes.
Ideal Pressure Control
Pressure control refers to managing the forces acting on the skis. It is essential to acknowledge and understand that the snow pushes on the skis and the skier making the skis and skier turn. Below, we highlight two types of pressure control - fore-aft balance and lateral balance. Look for the ideal pressure action: the skis bend from tip to tail, the outside ski bends more than the inside ski, and the skis remain in contact with the snow.
Fore and Aft Balance
When looking for the ideal use of fore-aft pressure, look for the front of both skis to press against the snow at the initiation of the turn. The skier creates fore-aft pressure through flexion and extension to control the bend of the skis. Here are some starter questions to reflect on while observing a skier’s fore/aft pressure control:
Are the ankles, knees, and hips joints flexing?
Is the spine slanted forwards, upright, or aft?
Are some joints flexed more than others or are the joints flexing proportionate to one another
Does the flexion of the joints move throughout the turn or does the skier remain fixed and the joints don’t flex and extend?
Ideal use of fore and aft pressure: The skier's head is ahead of their feet
Real use of fore and aft pressure: The skier’s head is behind their feet
Lateral Balance
When looking for ideal pressure control skills, the outside ski should bend more than the inside ski, and both skis bend from front to back while (in most cases) maintaining contact with the snow. Here are some starter questions to reflect on while observing the skier’s pressure control:
What is the relationship between the two legs? Is one more bent than the other or do they look similar?
How much or little flexion is between the two legs and where does it occur in the turn?
Where is the upper body titling?
Where is the upper body facing?
Ideal outside ski pressure - The skier has a short inside leg, a longer outside leg, and their upper body is tipped toward the outside ski.
Real outside ski pressure - The skier has a slightly shorter inside leg but the whole body is tipped to the inside of the turn or back up the hill
Ideal Rotational Control
Rotational movements can occur in several different places in the body. We will briefly look at two movements that skiers commonly use to control where the skis are pointed and how each affects the skis’ performance: leg and body rotation.
Leg Rotation
Leg Rotation refers to how the legs move in the hip sockets to control the rotational movement of the skis. The movement originates in the hip and extends down the leg and includes turning of the upper leg (femur) and the lower leg below the knee. As the ankles, knees, and hips are flexed, abduction and adduction also play a significant role. Since our legs are slightly bent when we ski, all of these movements are used in combination most of the time. Leg rotation is the most versatile and effective option for rotational control of the skis. We can control how long the skis are turning, the amount that they turn, the speed they turn, and when they turn. Likewise, we can control each ski independently of each other to assist with turning.
Upper-Body Rotation
Upper-body rotation is pretty much what it sounds like. The skier turns their upper body first, and then the legs turn in the same direction. This can be a large movement that includes the head, torso, shoulders, and pelvis or it can be much more subtle where the skier only slightly turns just the pelvis and part of the torso before the legs turn. Upper-body rotation is typically an undesirable movement since it is hard to control the duration, amount, rate, timing and intensity of the skis turning. Likewise, it usually results in the inside ski starting to turn before the outside ski. Once the skis start turning, it can be difficult to control them, and the skier will have to use another movement to resist the skis from turning.
Finish of the Turn
A great place to catch visual body cues of ideal rotational control is the finish of the turn. The skier’s legs should be turned across the fall line more than the upper body and the upper body should be aimed towards the next turn. As you view the pictures and videos below, here are some starter questions to reflect on while observing the skier’s rotational control:
Is the upper body rotating before the lower body or is the upper body stable with active rotation of the legs?
How much does the body rotate and where does the movement occur during the turn?
Do both legs turn the same amount, at the same time, or in the same direction?
Ideal rotational control - The lower body is rotated across the fall line more than the upper body. The upper body is aiming down the fall line.
Real rotational control - The whole body is rotated across the fall line during the finishing phases of the turn.
Ideal Edge Control
Edge control refers to how the skis are tipped on and off their edges. Skiers must learn how to control the edges of the skis through increasing and decreasing the angle of the ski on the snow. Controlling the edging movements of the skis requires skiers to learn how to put the skis both on and off edge. In order to turn, we must tip the skis onto their edges and then maintain the edge angle we want.
To link turns, we must learn how to change edges smoothly and progressively so as not to disturb our balance. Skiers learn how to control the skis’ edge angles on the snow through a combination of two movements: angulation and inclination.
Using angulation and inclination in combination is the trick to effective edge control movements. Skiers will use a combination of these movements to determine how long they want their edging movements to last, how much or little edge angle they want to have, how quickly they want to tip the ski on or off edge, and when we want to change the edge angle. Too much of one or the other in the wrong context won’t allow us to balance on our edges while we turn.
Inclination
Inclination in its most simple form is moving your center of mass to the inside of the turn. Skiers use inclination to balance against the lateral forces of the turn much like how we lean into a turn on a bike. When done accurately this happens from the feet up to the head. When done inaccurately, skiers lean their upper body into the turn while their feet and legs do not or they incline without sufficient angulation for the task.
Angulation
The two types of angulation commonly used in skiing are knee angulation and hip angulation. Knee angulation is when the lower leg is tipped more than the upper leg with an angle at the knee. Hip angulation is when the legs are tipped more than the upper body with an angle at the hip socket. Using the feet and legs like this to control edge angles is a precise way to control the skis. The tipping movement in the legs is actually a combination of tipping the feet and legs, flexing the knees and hips, and the different types of leg rotation. By using this combination of movements, a skier can avoid putting too much lateral stress on the knee while maintaining a precise manner of controlling the edge angle.
Inclination with angulation
Inclination without angulation
Edge Control
This video shows the tipping of the skis relative to the length or longitudinal axis of the skis. Here are some start questions to reflect on as you view the pictures and videos below.
What parts of the body are tipping?
What part(s) of the body is/are angulating?
How much are they angulating?
What is the combination of angulation and inclination?
Is there too much of one over the other?
Do both legs tip the same amount, at the same time, or in the same direction?
Ideal edge control - The lower body is tipped to the inside of the turn more than the upper body
Real edge control - The whole body is tipped to the inside of the turn