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Intrinsic feedback factors producing inertial compensation in muscle
1Department of Physiology and Biophysics, University of Tennessee, Memphis, Tennessee 38103, USA.
Biophysical Journal
|February 13, 2009
Summary
Skeletal muscle exhibits load-inertia compensation. Its length-tension and force-velocity properties function as servo feedback, making it a position servo, not a force motor.
Area of Science:
- Muscle physiology
- Biomechanical engineering
- Neuroscience
Background:
- Skeletal muscle exhibits load-inertia compensation, a phenomenon not fully understood.
- Previous models often treated muscle as a simple force generator.
Purpose of the Study:
- To elucidate the factors responsible for load-inertia compensation in skeletal muscle.
- To analyze muscle's functional characteristics within a servo system framework.
Main Methods:
- Determined cat skeletal muscle force output.
- Varied muscle length and stimulus pulse rate as experimental parameters.
- Represented findings in a system diagram for analysis.
Main Results:
- The length-tension relationship acts as non-neural servo feedback.
- The force-velocity curve functions as oscillation-damping velocity feedback.
- Stimulus pulse rate non-linearly influences response, acting as an input element.
Conclusions:
- Skeletal muscle's inherent properties suggest it operates as a position servo.
- These characteristics enable effective load-inertia compensation.
- Muscle's signal handling aligns more with a position control system than a force-generating motor.
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