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Lower-Limb Biomechanical Characteristics Associated with Unplanned Gait Termination Under Different Walking Speeds
Published on: August 25, 2020
The relationships between muscle, external, internal and joint mechanical work during normal walking
Kotaro Sasaki1, Richard R Neptune, Steven A Kautz
1Department of Mechanical and Biomedical Engineering, Boise State University, Boise, ID 83725, USA.
The Journal of Experimental Biology
|February 17, 2009
Summary
Estimating muscle mechanical work during walking is complex. Net joint work can approximate muscle work when passive joint work is minimal, but external and internal work are unreliable predictors.
Area of Science:
- Biomechanics
- Human Movement Analysis
- Musculoskeletal Modeling
Background:
- Muscle mechanical work is crucial for understanding human movement.
- Existing methods for estimating muscle work include external, internal, and joint work.
Purpose of the Study:
- To investigate the relationships between different mechanical work estimates during human walking.
- To assess the accuracy of these estimates for quantifying musculotendon and muscle fiber work.
Main Methods:
- A muscle-actuated forward dynamics simulation was employed to quantify mechanical work measures.
- Analysis focused on total joint work, net joint work, external work, and internal work during walking.
Main Results:
- Total joint work underestimated total musculotendon work due to co-contractions.
- Net joint work approximated net musculotendon work when passive joint work was negligible.
- External and internal work measures were not reasonable estimates of total musculotendon work.
Conclusions:
- Joint work has limitations in estimating musculotendon work.
- Net joint work can serve as a proxy for net muscle work under specific conditions (negligible passive joint work).
- External and internal work should not be used to estimate musculotendon work.
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