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Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
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Association between static stretching load and changes in the flexibility of the hamstrings
Kosuke Takeuchi1, Kazunori Akizuki2, Masatoshi Nakamura3
1Department of Physical Therapy, Kobe International University, Kobe, Hyogo, Japan. ktakeuchi@kobe-kiu.ac.jp.
Scientific Reports
|November 6, 2021
Summary
Higher intensity static stretching significantly improves hamstring flexibility by increasing the load applied. This research highlights the importance of stretching load for enhancing range of motion and reducing muscle-tendon stiffness.
Area of Science:
- Biomechanics
- Sports Science
- Musculoskeletal Health
Background:
- Static stretching is a common method to improve flexibility.
- The relationship between stretching load and its effects on muscle properties requires further investigation.
Purpose of the Study:
- To investigate the association between static stretching load and hamstring flexibility changes.
- To determine the impact of different stretching intensities on range of motion and muscle-tendon unit stiffness.
Main Methods:
- Twelve healthy men participated in a randomized controlled trial.
- Static stretching was applied for 60 seconds at 100% and 120% of perceived discomfort (POD).
- Measurements included knee extension range of motion (ROM), passive torque, and muscle-tendon unit stiffness before and after stretching.
Main Results:
- Both stretching intensities increased knee extension ROM and passive torque at end ROM (p < 0.01).
- Muscle-tendon unit stiffness decreased significantly only at 120%POD intensity (p < 0.01).
- Significant correlations were found between static stretching load and relative changes in knee extension ROM (r=0.56) and muscle-tendon unit stiffness (r=-0.76).
Conclusions:
- Static stretching load significantly influences changes in hamstring knee extension ROM and muscle-tendon unit stiffness.
- High-intensity static stretching, characterized by a higher load, is effective for improving hamstring flexibility.
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