Pro Ski simulators were designed in accordance with the 7 principles of ski biomechanics
1. Stability and Mobility
A narrower stance will facilitate agility and quickness, while a wider stance and lowering the center of gravity will enhance stability and allow the ski racer to better resist lateral forces
2. Force (F = mass x acceleration)
The production of maximum force requires the alignment and use of as many joints as possible.
Every active movement around a joint axis results from a muscular contraction that creates a TORQUE (a force acting some distance from an axis through a lever
arm). These torques rotate bones resulting in a combination of movements against the ski boot, ski, terrain and snow conditions. The more torques acting together
(not in opposition), the more total force applied.
3. Velocity (acceleration in a direction)
The production of maximum velocity requires the use of joints in summation.
- The amounts of each depend on speed, turn shape, and phase of the turn.
- The execution phase represents the coiling movement.
- The transition phase represents the unwinding movement where the hips move from inside the arc to recover back on top of the skis together with the knee and ankle in rapid succession. The positioning of the center of mass influences the maintenance or the control of the speed.
4. Impulse (I = Force x Time)
The greater the applied impulse, the greater the increase in velocity.
- Impulse is force multiplied by time. While it is conceivable to have high impulse using a minimum force over a long period of time, a ski racer really wants to create impulse with significant force in a short period of time (especially in the technical events).
- Increasing velocity by applying an impulse at the right moment (critical instant) in a turn and in the right direction.
- This is how ‘pumping’ the ski on the flats works to increase velocity. By applying an impulse at the critical instant, the ski racer is loading the ski much like a trampoline. This energy will be returned to the ski racer to help move the feet laterally at the switch, and to help propel the center of gravity/mass into the desired line of travel.
5. Direction
Movement occurs in the direction opposite to the applied force.
None of this is possible without a stable carving outside ski or platform. A skidded ski does not support these dynamic movements or the transmission of force required to produce them.
6. Angular Motion
Produced by the application of a force acting at some distance from an axis, that is, by a torque.
The ski racer must resist or manage this torque in order to remain stable and carve. By resisting the torque, the ski racer is able to store energy like a twisting spring. Torque is managed by upper body separation at the top of the turn and resisted in the core during the execution phase. Unwinding takes place in the transition phase.
7. Angular Momentum (L = Velocity x mass)
Is constant when an athlete or object is free in the air.
- Initiated by some impulse acting a distance from the axis of rotation.
- The ‘system’ now has energy stored in it in the form of momentum.
- A turn that is not finished on the ground will be completed (and then some!) in the air.