Reliability and validity of the new portable Nordic hamstring test device (IVMES H-Bord)

The aim of this study is to determine the reliability and validity of the IVMES H-Bord eccentric hamstring strength measurement device. Thirty-eight healthy male athletes (age: 20.9 ± 2.11 years, height: 1.79 ± 0.03 m, body weight: 76.6 kg, body mass index: 22.6 ± 0.69 kg/m2) participated in this study. Each test protocol was applied in eccentric mode and isometric mode respectively. Between-session test-retest reliability of the IVMES H-Bord was analyzed for the intraclass correlation coefficient (ICC) with 95% coefficient intervals (CI). Validity of the IVMES H-Bord was examined for eccentric mode (NHTecc), and isometric mode (NHTiso) using Pearson’s correlation coefficient with 95% CI and limits of agreement. Bland-Altman plots were also created to provide a representation of the agreement between two test devices. Strong correlations, good ICC values and acceptable typical errors of the estimate were observed between the NHT and isokinetic strength testing (IST) during both limbs with no proportional bias for validity analysis. In conclusion, the “IVMES H-Bord” is a reliable and valid measurement device for eccentric hamstring muscle strength and it provides important advantages for medical staff, fitness coaches and practitioners because it is portable, low cost, and field-based assessment.