It seems as though most skiers and instructors choose one or the other or believe that one is more beneficial than the other. This article discusses the benefits of both and how to use both techniques effectively.
Beginning with the most important questions – What is knee angulation and what is hip angulation? To tip the skis on edge something must move inside the arc of the turn. Without this happening the skis will remain flat.
When performing knee angulation, the knees move inside the arc to tip the skis on the edge. An angle forms at the knee and the upper body (everything above the knee) remains balanced over the outside ski. When using hip angulation the pelvis moves inside the arc creating edge angle. An angle forms at the hip so that the upper body (everything above the hip) can remain balanced over the outside ski. In either case, when the appropriate part of the body moves inside the arc or inclines into the turn, an angle should form at one of the joints to maintain balance over the outside ski preventing “banking” (the body leaning in as one block and ending up on the inside ski). So while reading this article it is important to remember that inclination causes edge angle and angulation creates balance against or over the outside ski.
The ability to move the knees inside the turn is a very difficult skill to master. It is a very fine skill that is difficult to perform while moving on skis. While it looks like the knee bends sideways, this is not actually possible. Knee angulation goes hand in hand with pronation and supination of the foot. You can try this while sitting there. In a seated position, roll onto or press on the arch of your right foot (you may feel your your pinkie toe lift in the air). You are now pronating your foot. As this happened your knee would have felt inclined to move inward. To continue moving the knee in, one must continue to rotate the femur inward while the foot remains in a pronated position. It is the combination of twisting the femur inward while pronating the foot that causes the knee to appear to move inwards.
This movement of knee angulation allows a lot of edge very quickly. This way of edging is particularly required for performing short turns as a short turn requires everything to happen at a faster pace.
Knee inclination/angulation is most useful during the turn transition and initiation. During the transition the skis must be tipped from one set of edges (uphill) to the other set of edges (downhill) to gain immediate grip at the top of the turn. As the skis track away from the body, they must be guided out on their edges which requires the use of the knees. Focusing on this movement of the knees as the hips cross the skis is the most efficient way to edge during these phases of the turn because it requires the least amount of travel. You will see in the below diagram that when changing edge, the distance travelled by the knees is far less than the distance travelled by the hips. It is important to note that while one is trying to actively use the knees during the transition to change edges, the whole body is moving across the skis to facilitate this. The knees are not the only part of the body that is moving to the other side of the skis. That said, during a high performance short turn it is not uncommon to see the knees further inside the turn than the hips during the initiation to gain early edge.
Without the ability to perform knee inclination/angulation, one is very restricted when performing short turns. Generally when a skier is weaker at this skill, they will skid the top part of the turn or “heel push”, as their ability to change edges and gain grip early in the turn is dramatically reduced. Both of these traits are very common in those that are new to short turns.
While knee inclination/angulation creates very high edge angles very quickly, it does put the body in a position that is very weak when dealing with the pressure that is created through the remainder of the turn. Have a look at the diagram below. You can see quite clearly that when this amount of torque and bend is placed on the knee joint, the load baring capability of the knee (and legs in general) is severely diminished.
Unlike knee angulation, using your hip puts you in a very strong position. Your outside leg is straighter with less torque and therefore its ability to cope with a large amount of pressure created through the turn is increased. Moving the hip in to an angulated position is relatively easy in theory. The hip moves in similarly to the way the platen on a type writer moves the piece of paper laterally. To angulate effectively once moved in, there must be some separation between the direction the pelvis and the direction the legs are pointing. This is created by the skis being either twisted by the legs (slow moving turn) or the skis travelling on a purely carved arc which in turn twists the leg while the hips remain still (not follow follow the direction of the skis). Slight flex in the hip joint then creates an angle at the hip and allows the upper body/balance to remain over the outside ski and an angle to form in the hip. A lot of people talk about bending sideways over the outside ski like a banana but this causes a bending of the lower spine and can in fact cause damage if done under pressure. In this photo the arrows show the direction the hips and legs/skis are pointing. You can also see the spine remains straight and the shoulders/pelvis are parallel.
Hip inclination/angulation is particularly useful when performing medium/long turns, as the pressure is greater (than in a short turn) and is felt for a longer period of time. It is also particularly useful during the middle and completion phases of the turn, as the pressure that is dealt with during these phases is much great than any other phase.
Unlike using the knees, the hip takes a little while to move inside and is therefore not as quick. It does create the highest edge angle but is a long time in the process. Using the hips to gain edge can also disrupt a skier’s balance if done incorrectly. Such a large part of the skier’s mass must shift to the inside that it can cause the skier to fall to the inside, particularly if done on flatter terrain or at slower speeds.
Hip inclination/angulation is often used by intermediate and advanced skiers as a way of edging. It is an easier move to perform as it uses gross motor movements, unlike the fine motor skills required with knee inclination/angulation. It is also an “easier” way to edge if one stands in a very tall, upright, lazy position.
So which is best?
As you can understand, both have their place during a turn. When performing a short turn there is heavy emphasis on the ankle and knee to change edge and increase the edge early in the turn. As the leg extends and the ski travels out to the side on edge, the hip is left inside the arc creating hip angulation. Through the middle of the turn the outside leg is in a straighter position with a larger part of the body (hips) inside to deal with the increasing pressure that is created.
When performing a medium or long turn there is a lot more emphasis on hip inclination/angulation as the pressure created is greater (as mentioned above). With this in mind, there is more emphasis placed on “projecting” the hip during the transition, or more “actively crossing over” during the transition to incorporate the hip as much and as soon as possible. While this is happening it still important that one is aware of the ankle and knee, as this creates grip while the hip is getting from one side of the ski to the other.
It is also important to understand that when using the hip to edge, there are 2 ways to achieve the same position: 1) from a middle position, one can incline and move the hip inside the arc of the turn into an angulated position; 2) from a low transition position, one can extend (preferably by guiding the skis on edge) the legs and feet out to the side, leaving the hips inside the arc in an angulated position. Both of these result in a similar hip angulated position in the middle of the turn. Which method is used will depend on the type of transition, size and objective of the turn.
Neither knee nor hip angulation happens on its own. When using the hip, there is still mild knee angulation visible. When using the knees, the hip still has to move inside to some degree to facilitate the knee movement. Whether you are more proficient at one than the other, or like one more than the other, in every turn both joints are required to edge the ski efficiently and still maintain balance.
I hope this article has helped you to think about edging in new ways and gives you something to try when you are next on the slopes!