Ergonomic analyses of downhill skiing

Area of Science:

• Sports Science
• Biomechanics
• Motor Learning

Background:

• Electromyography (EMG) provides objective measures of muscle activity.
• Understanding muscle activation patterns is crucial for optimizing athletic performance and injury prevention in skiing.

Purpose of the Study:

• To provide electromyographic feedback for pedagogical advice in ski motor learning.
• To analyze the ergonomics of ski materials (compact, soft, competition skis) through EMG.
• To compare muscular activity in different snow conditions during a simulated ski competition.

Main Methods:

• Collected EMG data from elite skiers (n=25, n=6) performing basic ski drills (Stem Christie, Stem Turn, Parallel Christie) and a simulated slalom.
• Analyzed integrated EMG (iEMG) and linear envelopes (LEs) from standardized positions, motions, and slopes.
• Utilized portable EMG recording equipment and surface electrodes on-site in the French Alps.

Main Results:

• A high level of co-contraction was observed in lower limb extensors and flexors, particularly during the extension phase of ski movements.
• The Stem Christie and Parallel Christie drills exhibited higher rhythmic movement percentages (92% and 84%, respectively).
• EMG analysis provided insights into muscle intensity and patterns across different skis and snow conditions.

Conclusions:

• EMG feedback can inform pedagogical strategies for ski motor learning.
• Muscle co-contraction patterns are significant during skiing, especially in extension phases.
• Rhythmic activity is pronounced in specific ski drills, offering benchmarks for technique analysis.