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Corticospinal Excitability Modulation During Action Observation
Published on: December 31, 2013
Neural modulation of muscle-tendon control strategy after a single practice session
Kuniaki Hirayama1, Toshimasa Yanai, Hiroaki Kanehisa
1Graduate School of Sport Sciences, Waseda University, Saitama, Japan.
Medicine and Science in Sports and Exercise
|March 29, 2012
Summary
A single practice session optimized muscle-tendon unit behavior during countermovement jumps (CMJ) by altering neuromuscular activities. This enhanced performance by increasing impulse and modifying fascicle and tendon dynamics.
Area of Science:
- Biomechanics
- Neuromuscular Physiology
- Sports Science
Background:
- The countermovement jump (CMJ) is a fundamental athletic movement.
- Understanding neuromuscular adaptations is key to improving jump performance.
Purpose of the Study:
- To investigate if a single practice session can alter musculotendinous behavior during CMJ.
- To examine the role of neuromuscular activity modulation in these changes.
Main Methods:
- Eight males performed CMJ and non-CMJ plantarflexion before and after a practice session.
- Electromyography (EMG) of leg muscles and ultrasonography of the gastrocnemius were used.
- Force-time data provided impulse and tendon behavior estimations.
Main Results:
- Impulse significantly increased in CMJ post-practice, but not in non-CMJ.
- Gastrocnemius fascicle lengthening/shortening decreased, while tendon shortening increased during CMJ.
- The neural activation time lag decreased after practice.
Conclusions:
- A single practice session can optimize muscle-tendon unit behavior during CMJ.
- Neural adaptations play a crucial role in improving CMJ performance.
- These findings highlight the plasticity of the neuromuscular system in response to training.
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