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Muscle activity in slalom and giant slalom skiing
R A Hintermeister1, D D O'Connor, C J Dillman
1Steadman Hawkins Sports Medicine Foundation, Vail, CO 81657, USA.
Medicine and Science in Sports and Exercise
|March 1, 1995
Summary
Competitive skiers show similar muscle activity in slalom (SL) and giant slalom (GS) skiing. Electromyography (EMG) revealed high muscle engagement throughout turns, with minor differences between SL and GS events.
Area of Science:
- Biomechanics of alpine skiing
- Sports physiology
- Human movement analysis
Background:
- Alpine skiing involves complex movements requiring significant muscular effort.
- Understanding muscle activation patterns is crucial for performance optimization and injury prevention.
Purpose of the Study:
- To compare electromyography (EMG) patterns in competitive skiers during slalom (SL) and giant slalom (GS).
- To quantify muscular activity in leg and trunk muscles during different skiing phases.
Main Methods:
- Surface electrodes and telemetry were used to monitor EMG activity in twelve muscles.
- Video analysis segmented skiing into distinct phases for SL and GS.
- Quantitative EMG parameters (average amplitude, peak amplitude) were analyzed.
Main Results:
- Most monitored muscles exhibited moderate to high activity throughout turns (58%-112% maximum voluntary contraction).
- High peak amplitudes were linked to resisting centrifugal and gravitational forces.
- Surprisingly similar muscle activity was observed between SL and GS, with minor significant differences in specific muscles.
Conclusions:
- Alpine skiing, across SL and GS, relies on substantial and consistent muscular engagement.
- Co-contraction suggests a quasistatic component contributing to skiing stability.
- Minor variations in muscle activation exist between SL and GS, highlighting sport-specific demands.
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