Reliability and Validity of a Wii Balance Board-Based Nordic Hamstring Test for Assessing Eccentric Hamstring Strength

Objective: This study evaluated the reliability and validity of the Nordic Hamstring Test (NHT) performed using a Wii Balance Board (WBB) for assessing eccentric hamstring strength, compared with a conventional isokinetic dynamometer (CSMI). Design: Cross-sectional validation study. Methods: Twenty-eight healthy young adults participated. Each performed three trials of the WBB-based NHT and eccentric knee extension testing using the CSMI at 60 °/s. Peak force and peak torque values were recorded and normalized to body weight. Reliability and validity were evaluated using standard statistical analyses. Results: The WBB-NHT demonstrated excellent within-session reliability. Peak force measured by the WBB-NHT showed significant positive correlations with peak torque obtained from the CSMI. A significant mean difference between the two measurement methods was observed. Conclusions: The WBB-based NHT provides reliable and valid measures of relative eccentric hamstring strength in healthy young adults. Its low cost and portability suggest that it may be a practical assessment tool in clinical and sports settings.