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Published on: August 18, 2023
Interaction between elastic energy utilization and active state development within the work enhancing mechanism
Hiroshi Arakawa1, Akinori Nagano, Shinsuke Yoshioka
1Department of Life Sciences (Sports Sciences), Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan. cc67703@mail.ecc.u-tokyt.ac.jp
Summary
Elastic energy utilization and active state development time synergistically enhance work output during countermovement (CM). The relative contribution of each factor depends on the series elastic element (SEE) length.
Area of Science:
- Biomechanics
- Human Movement Analysis
- Muscle Physiology
Background:
- Countermovement (CM) enhances work output through elastic energy utilization and active state development.
- Understanding the interplay between these factors is crucial for optimizing athletic performance.
Purpose of the Study:
- To quantitatively investigate the interaction between elastic energy utilization and active state development time during CM.
- To determine the individual contributions of these factors to enhanced work output.
- To examine the effect of series elastic element (SEE) length and active state development speed.
Main Methods:
- A Hill-type model of the muscle-tendon complex (MTC) was employed.
- Forward dynamics simulations were conducted.
- Investigated a range of SEE lengths (0.625-10x optimal contractile element length) and active state development rates.
Main Results:
- For shorter SEE muscles, active state development time contributed more to work output than elastic energy utilization.
- For longer SEE muscles, elastic energy utilization played a more significant role.
- Increasing the speed of active state development substantially augmented SEE work output during CM.
Conclusions:
- Elastic energy utilization and active state development time interact synergistically to enhance work output during CM.
- The relative importance of elastic energy utilization versus active state development time is dependent on SEE length.
- These findings provide quantitative insights into the mechanisms underlying work enhancement in CM actions.
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