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Determining The Electromyographic Fatigue Threshold Following a Single Visit Exercise Test
Published on: July 27, 2015
An electromyographic comparison of 4 closed chain exercises
J T Hopkins1, C D Ingersoll, M A Sandrey
1Indiana State University, Terre Haute, IN.
Journal of Athletic Training
|March 25, 2006
Summary
The FlexCord front and back pull exercises show higher biceps femoris muscle activity, suggesting greater cocontraction for knee rehabilitation. The FlexCord front pull also boosts vastus medialis activity, beneficial for patellofemoral issues.
Area of Science:
- Biomechanics and Exercise Physiology
- Sports Medicine and Rehabilitation
Background:
- Closed chain exercises are crucial for knee muscle strengthening in clinical settings.
- Understanding muscle activation patterns is key to optimizing exercise selection for rehabilitation.
Purpose of the Study:
- To compare the electromyographic (EMG) activity of vastus lateralis, vastus medialis, and biceps femoris muscles during four closed chain exercises.
- To identify which closed chain exercise elicits the highest muscle activation for potential use in knee rehabilitation.
Main Methods:
- A 4x3x2 factorial design with repeated measures was employed.
- Thirty-eight healthy female college students participated.
- EMG data were collected from vastus lateralis, vastus medialis, and biceps femoris during unilateral quarter squat, lateral step-up, FlexCord front pull, and FlexCord back pull exercises.
Main Results:
- FlexCord front pull and back pull demonstrated significantly higher biceps femoris activity compared to quarter squat and step-up.
- The FlexCord front pull elicited greater vastus medialis activity during knee extension than the other exercises.
- No significant differences were found in vastus lateralis activity across the exercises.
Conclusions:
- Higher biceps femoris activity in FlexCord exercises suggests increased cocontraction, potentially beneficial for anterior cruciate ligament (ACL) rehabilitation.
- The elevated vastus medialis activity during the FlexCord front pull indicates its potential efficacy for patellofemoral pain syndrome rehabilitation.
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