Related Experiment Video
Updated: Jul 7, 2026
08:40
Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity
Published on: June 12, 2019
Technical report: Reliability and validity of the iSAM 9000 isokinetic dynamometer
Julia C Orri1, Gibson F Darden
1Department of Exercise and Sport Science, University of San Francisco, San Francisco, California, USA. jorri@usfca.edu
Journal of Strength and Conditioning Research
|February 26, 2008
Summary
The INRTEK iSAM 9000 isokinetic dynamometer demonstrates excellent mechanical reliability and validity, showing high reproducibility and strong correlations with the Cybex 6000. This new device offers precise torque measurements for human muscle performance assessment.
Area of Science:
- Biomechanics
- Human Movement Analysis
- Sports Science
Background:
- Isokinetic dynamometers are crucial for assessing muscle strength and performance.
- Evaluating the reliability and validity of new devices is essential before widespread adoption.
- The INRTEK iSAM 9000 is a novel isokinetic dynamometer requiring validation against established systems.
Purpose of the Study:
- To assess the mechanical reliability and validity of the INRTEK iSAM 9000 isokinetic dynamometer.
- To compare torque measurements between the iSAM 9000 and a traditional device (Cybex 6000).
- To inform refinements for future generations of the INRTEK device.
Main Methods:
- Sixty healthy volunteers (40 men, 20 women) participated.
- Isokinetic testing at 60°/sec for shoulder, knee, and trunk flexion/extension.
- Measurements were taken using both the Cybex 6000 and the INRTEK iSAM 9000.
- Reliability and validity assessed using Intraclass Correlation Coefficients (ICC), Standard Error of Measurement (SEM), and Pearson correlation (r).
Main Results:
- High reproducibility for torque measurements by the iSAM 9000 (ICC range: 0.94–0.98; SEM range: 5.2–29.7).
- Very high correlations between iSAM 9000 and Cybex 6000 torque values (r = 0.84–0.93).
- The iSAM 9000 yielded significantly higher peak torque values in several joint movements compared to the Cybex 6000 (P < 0.05).
Conclusions:
- The INRTEK iSAM 9000 exhibits strong mechanical reliability and validity for isokinetic torque measurement.
- High correlation with the Cybex 6000 supports the iSAM 9000's validity.
- Findings will guide improvements in test protocols and reliability for future INRTEK devices.
