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Relationship Between Force Production During Isometric Squats and Knee Flexion Angles During Landing
Harry Fisher1, Mitchell L Stephenson, Kyle K Graves
11Division of Kinesiology and Health, University of Wyoming, Laramie, Wyoming; and 2Department of Theatre and Dance, University of Wyoming, Laramie, Wyoming.
Journal of Strength and Conditioning Research
|November 14, 2015
Summary
Women athletes
Area of Science:
- Biomechanics
- Sports Medicine
- Orthopedics
Background:
- Decreased knee flexion during landing increases anterior cruciate ligament (ACL) loading.
- Mechanisms behind reduced self-selected knee flexion angles during landing remain unclear.
Purpose of the Study:
- To investigate the relationship between isometric squat strength at various knee flexion angles and landing knee flexion angles.
- To determine sex-specific differences in this relationship.
Main Methods:
- 18 men and 18 women recreational/collegiate athletes performed isometric squats at 35°, 55°, 70°, and 90° knee flexion, with vertical ground reaction forces measured.
- Participants also completed a jump-landing-jump task with lower extremity kinematics recorded.
Main Results:
- For women, peak isometric squat force at 55° and 70° correlated significantly with initial contact and peak landing knee flexion angles.
- These correlations were stronger at greater isometric knee flexion angles.
- No significant correlations were found for men.
Conclusions:
- Posture-specific strength may influence self-selected knee flexion angles during landing in women.
- These findings highlight potential sex-specific neuromuscular strategies during landing.
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