High Performance Skiing Model

By Jon Ballou, 2006.

In recent years the international concepts of what defines ‘good skiing’ in the context of high performance on prepared (groomed/hard) snow have become noticeably similar. In conversations with current examiners, coaches, athletes and instructors I have noticed that rarely are there discrepancies in what we believe the outcome of the skier or performance of the skis should be, even if we think there might be.

Quite often when discrepancies or two-sided conversations arise regarding the outcome of ski performance the conversation is actually about methodology. Personal beliefs on ‘how’ to bring a skier to optimal performance vary greatly from culture to culture. With all the variations in ‘how’ the result is still quite similar.

In the model below I have tried to outline optimal ski performance and the movements necessary to achieve this.

Sequence of events

1. Edge change occurs when CoM (centre of mass) crosses the path of the skis.
2. Both legs tip into the turn at the same rate that the CoM moves inside the turn (inclination).
3. As the body inclinates, femurs rotate simultaneously creating rotational separation between the upper and lower-body (biomechanically speaking, anything under 6 degrees is purely lateral, thus the separation created will not technically be rotational). During this phase (before the fall line), skis are redirected to some degree (this may be a very, very small amount). A) This part of the turn is two-footed. Pressure may or may not be established on the outside ski (this is determined by skier intent). B) Edge angle is achieved through inclination and lateral movement of the femur. However, pressuring movements are minimal.
4. As the skis enter the fall line, pressure is distributed to the outside ski. This happens naturally, but needs to be encouraged by accurate body movements (pelvis, spine).
5. Leg rotation (rotational tension) is maintained or increased through or after the fall line.
6. To increase stability, grip, and maintain or increase redirection of the outside ski, angulation begins. Due to rotational separation, angulation is achieved through flexion. At this point, the CoM begins to move towards the outside ski.
7. During this pressuring phase, the outside ski becomes increasingly more dominant. (70% point – Twardokens law)
8. After this point, the skis begin to flatten due to CoM traveling back towards and over the base of support (center of skis). This can be achieved through extension or flexion of both legs or independently.
9. Repeat as necessary.

How it looks

Inclination: Tilting on one plane. This brings the mass inside the turn.

Angulation: Inclination on multiple planes. This brings the mass towards path of the outside ski.

Result

The closer the Centre of Mass’ line is to the path of the ski, the earlier the outside ski can establish dominance.

Jon Ballou