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Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Concurrent validity of four clinical tests used to measure hamstring flexibility
D Scott Davis1, Rich O Quinn, Chris T Whiteman
1Division of Physical Therapy, Department of Human Performance and Exercise Science, West Virginia University, Morgantown, West Virginia, USA. dsdavis@hsc.wvu.edu
Journal of Strength and Conditioning Research
|June 14, 2008
Summary
Four common clinical tests for hamstring muscle length show poor to fair concurrent validity. Researchers and clinicians should adopt the knee extension angle (KEA) test as the gold standard for accurate hamstring length measurement.
Area of Science:
- Biomechanics
- Musculoskeletal Assessment
- Clinical Measurement
Background:
- Hamstring muscle length is crucial for flexibility and injury prevention.
- Several clinical tests exist, but their validity for measuring hamstring length is debated.
- Understanding the reliability and validity of these tests is essential for accurate clinical practice.
Purpose of the Study:
- To examine the concurrent validity of four clinical tests for hamstring muscle length: knee extension angle (KEA), sacral angle (SA), straight leg raise (SLR), and sit and reach (SR).
- To determine if these commonly used tests accurately measure the same construct of hamstring length.
- To provide evidence-based recommendations for the most reliable clinical measure of hamstring length.
Main Methods:
- A pilot study assessed intratester reliability of the four tests (N=10), showing good to excellent results (ICC=0.92-0.95).
- The main study involved 81 subjects (42 men, 39 women) randomly tested with the four assessments.
- Concurrent validity was analyzed using linear regression, correlation, and kappa statistics.
Main Results:
- Correlation coefficients for concurrent validity between the six test combinations ranged from poor to fair (r=0.45-0.65).
- The highest correlations were observed between Sit and Reach-Sacral Angle (0.65) and Straight Leg Raise-Sit and Reach (0.65).
- The Knee Extension Angle-Sacral Angle pair showed the lowest correlation (0.45).
Conclusions:
- The four clinical tests for hamstring length lack sufficient concurrent validity for interchangeable use.
- These tests may not accurately measure the same underlying construct of hamstring muscle length.
- The Knee Extension Angle (KEA) test is recommended as the gold standard for measuring hamstring muscle length.
