Related Experiment Video
Updated: May 16, 2025
07:30
Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
15.2K
Concentric Rate of Force Development, Squat Strength, and Faster Unloading Associated With Change-of-Direction
Naoyuki Yamashita1, Daisuke Sato2, Akio Nagae3
1Faculty of Arts and Sciences, Kyoto Institute of Technology, Kyoto, Japan.
Summary
Faster changes of direction (COD) in volleyball players depend on leg strength and explosive power. Enhancing concentric force production after braking is key for 10-m COD and COD deficit (CODD) performance.
Area of Science:
- Sports Science
- Biomechanics
- Athletic Performance
Background:
- Faster changes of direction (COD) are crucial for athletic performance.
- Leg strength and jumping ability partially correlate with COD performance but may not capture the full picture.
- Previous analyses overlooked additive and confounding effects in COD performance.
Purpose of the Study:
- To investigate the association between COD/COD deficit (CODD) performance and various physical metrics in female volleyball players.
- To identify key predictors of COD and CODD performance by adjusting for confounding factors.
- To explore the relationship between jump performance, leg strength, and sprint ability with COD/CODD.
Main Methods:
- Eighteen female intercollegiate volleyball athletes participated.
- Measurements included 10- and 20-m sprints, pro-agility tests, squat jump, countermovement jump (CMJ) height, and relative back-squat 1-RM (BS1RM).
- CMJ phase-specific performance, including force and rate of force development during eccentric and concentric phases, was assessed.
Main Results:
- For 10-m COD, concentric rate of force development (100ms), relative BS1RM, and squat-jump height were significant predictors.
- For 10-m CODD, absolute BS1RM and CMJ minimum power during unloading were retained.
- No significant predictors were identified for 20-m COD performance.
Conclusions:
- Leg strength and rapid concentric force production post-eccentric braking are vital for 10-m COD and CODD in volleyball.
- Targeting these specific physical attributes may enhance change-of-direction capabilities in athletes.
- Further research is needed to understand 20-m COD performance predictors.
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