Validity and Reliability of Isometric Muscle Strength using the Powrlink Portable Device

Keywords: Handheld Dynamometry, Portable Dynamometry Anchoring System, Powrlink, Muscle Strength, Validity


Background: A muscle strength testing device that is convenient, practical, reliable, and valid is essential in clinical and field settings. Objective: Therefore, the purpose of this study was to determine the validity and reliability of measuring isometric muscle strength with the Powrlink handheld dynamometer compared to an established force dynamometer. Method: Sixty-one university students (40 males and 21 females) completed two standardized testing sessions seven days apart. Each session consisted of a familiarization period followed by three peak isometric muscle strength tests. Intraclass correlation (ICC, model: two-way mixture with absolute agreement), standard error of measurement (SEM), minimum detectable change (MDC), and 95% limits of agreement (LOA) for intra- and inter-rater reliability were determined. Results: Test-retest reliability (ICC > 0.91) and intertrial reliability (ICC > 0.99) were excellent. No significant differences were observed in peak and mean knee forces and torques between the test and retest, indicating high test-retest reliability. Conclusion: The Powrlink device is portable, convenient, responsive, and cost-effective, has excellent test-retest reliability, and can be used to measure maximal isometric force in the clinic and in the field.

How to Cite
Shahidi, S. H., Özkaya, İbrahim, Karakaş, Çağatay S., Taşkıran, Y., & Esformes, J. I. (2023). Validity and Reliability of Isometric Muscle Strength using the Powrlink Portable Device. International Journal of Strength and Conditioning, 3(1).