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Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Lifting ability and leg strength
The Journal of Orthopaedic and Sports Physical Therapy
|January 1, 1991
Summary
For healthy young males, peak torque in knee and hip extensors predicts floor-to-knuckle lifting ability. This relationship was not found in females, suggesting sex-specific biomechanical factors influence lifting performance.
Area of Science:
- Biomechanics
- Exercise Physiology
- Sports Medicine
Background:
- Understanding the biomechanical factors influencing lifting ability is crucial for injury prevention and performance enhancement.
- Previous research has explored correlations between muscle strength and various functional movements.
Purpose of the Study:
- To investigate the relationship between lower extremity muscle peak torques and floor-to-knuckle leg lift performance in healthy adults.
- To identify potential predictors of lifting ability based on isokinetic and isometric strength measurements.
Main Methods:
- Twenty-four healthy adults (20-40 years) underwent testing for isokinetic peak torque (knee/hip extensors/flexors) using a Cybex II dynamometer.
- Isometric and maximum lifting ability were assessed using strain gauge and free weight/box methods, respectively, employing a squat technique with a neutral spine.
- Regression analyses were performed to determine correlations between strength measures and lifting performance.
Main Results:
- No significant correlations were found for the entire group.
- In 15 males, significant correlations were observed between isokinetic knee extensor peak torque (180°/sec) and hip extensor peak torque (30°/sec) with both maximum and isometric lifting abilities.
- No statistically significant correlations were identified for the nine female participants.
Conclusions:
- Isokinetic knee extensor and hip extensor peak torques may serve as predictors of floor-to-knuckle leg lifting ability in healthy young males.
- The findings suggest that sex-specific biomechanical differences may influence the relationship between muscle strength and lifting performance.
- Further research is warranted to explore these sex differences in more detail.
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