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The Reliability Of Three Isokinetic Knee-extension Angle-specific Torques
B L Arnold1, D H Perrin, E V Hellwig
1Brent L. Arnold is Doctoral Student in Sports Medicine at Curry School of Education, University of Virginia, Charlottesville, VA 22903.
Journal of Athletic Training
|October 1, 1993
Summary
This study found good reliability for concentric quadriceps muscle torque measurements at specific knee angles. However, clinicians should be cautious when interpreting small torque differences due to measurement error.
Area of Science:
- Biomechanics
- Kinesiology
- Sports Medicine
Background:
- Assessing muscle strength is crucial in clinical and sports settings.
- Isokinetic dynamometry is a common tool for measuring joint torques.
- Understanding the reliability of angle-specific torque measurements is essential for accurate assessments.
Purpose of the Study:
- To evaluate the test-retest reliability of concentric quadriceps muscle torque.
- To determine reliability at specific knee extension angles (30°, 60°, 75°).
- To provide guidance for clinicians using isokinetic dynamometry.
Main Methods:
- Twenty-five female university students participated.
- Concentric quadriceps torque was measured using a Kin-Com isokinetic dynamometer.
- Testing was conducted on two separate days, one week apart, at a speed of 60°/s.
Main Results:
- High intraclass correlation coefficients (ICCs) indicated good reliability at all tested angles: 0.84 (30°), 0.87 (60°), and 0.83 (75°).
- Standard errors of the measure ranged from 5.92 N.m to 7.65 N.m.
- The findings suggest reliable angle-specific torque measurements with the used protocol.
Conclusions:
- Angle-specific concentric quadriceps torques demonstrate good reliability.
- Clinicians should exercise caution when comparing torque differences below 12-16 N.m due to potential measurement error.
- The study provides valuable insights into the precision of isokinetic torque measurements.
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