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Ski jumping takeoff in a wind tunnel with skis
Mikko Virmavirta1, Juha Kivekäs, Paavo Komi
1Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland.
Journal of Applied Biomechanics
|September 8, 2011
Summary
Simulated ski jumping takeoffs in a wind tunnel revealed skis alter force distribution under the feet, emphasizing rear foot forces for optimal ski positioning. This research highlights wind tunnels as valuable tools for ski jumping analysis.
Area of Science:
- Biomechanics
- Sports Science
- Aerodynamics
Background:
- Understanding the biomechanics of ski jumping takeoff is crucial for performance enhancement.
- Previous research has primarily focused on in-situ conditions, limiting controlled environmental studies.
- The influence of equipment, specifically skis, on takeoff dynamics requires further investigation.
Purpose of the Study:
- To examine the effect of skis on the force-time characteristics during simulated ski jumping takeoff.
- To analyze anteroposterior balance during takeoff by differentiating force plate signals.
- To assess the feasibility and utility of wind tunnels for ski jumping research.
Main Methods:
- Simulated ski jumping takeoffs were conducted in a wind tunnel.
- Force plates recorded takeoff forces, with signals separated for front and rear foot analysis.
- Experiments were performed both with and without skis, under various wind conditions.
Main Results:
- Skis did not significantly alter overall force levels but changed force distribution under the feet.
- Increased force contribution from the rear part of the feet was observed, likely due to ski positioning.
- Jumpers reported a natural and subjectively easier takeoff experience with skis in the wind tunnel.
Conclusions:
- Skis influence the fine-tuning of force application during ski jumping takeoff.
- The wind tunnel provides a viable and effective environment for studying ski jumping dynamics.
- Future research on ski jumping takeoff biomechanics can benefit from wind tunnel methodologies.
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