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The effect of knee joint angle on torque control
Jacob J Sosnoff1, Stefani J Voudrie, Kyle T Ebersole
1Motor Control Laboratory, Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. jsosnoff@illinois.edu
Journal of Motor Behavior
|November 13, 2009
Summary
Knee joint angle significantly impacts quadriceps muscle torque control. Maximal voluntary contraction torque varied with angle, while relative torque variability decreased as knee flexion increased.
Area of Science:
- Biomechanics
- Neuromuscular Physiology
- Human Movement Science
Background:
- Understanding torque control is crucial for optimizing physical performance and rehabilitation.
- Quadriceps muscle function is vital for lower limb movements.
- Joint angle is a known factor influencing muscle force production.
Purpose of the Study:
- To investigate the influence of knee joint angle on quadriceps torque control.
- To analyze maximal voluntary contraction (MVC) and submaximal torque production across different knee flexion angles.
Main Methods:
- 12 healthy adults performed maximal voluntary contractions and submaximal torque tasks.
- Measurements were taken at knee flexion angles of 15, 30, 60, and 90 degrees.
- Torque output, absolute variability (standard deviation), and relative variability (coefficient of variation) were analyzed.
Main Results:
- Maximal voluntary contraction torque was highest at 60 degrees and lowest at 15 degrees knee flexion.
- Absolute torque variability increased with greater knee flexion (60 and 90 degrees).
- Relative torque variability (CV) decreased as knee joint angle increased.
Conclusions:
- Joint angle significantly affects quadriceps torque control strategies.
- Muscle torque control is modulated by joint kinematics.
- Findings support the hypothesis that joint angle influences torque regulation.
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