Ankle dorsiflexor muscle performance in healthy young men and women: Reliability of eccentric peak torque and work measurements

The aims of this study were: (i) to assess the test-retest intrarater relia bility of eccentric ankle dorsiflexor muscle performance in young healthy m en and women using the Biodex dynamometer; and (ii) to examine different st atistical indices for the interpretation of reliability, Thirty men and wom en (age 22.5 +/- 2.5 years, mean +/- S.D.) performed three maximal eccentri c contractions at 30 degrees /second and 90 degrees/ second, with 7-10 days between test sessions. Reliability was evaluated with three intraclass cor relation coefficients (ICC1,1, ICC2,1 and ICC3,1), and was excellent for pe ak torque (ICC 0.90-0.96) and good to excellent for work (ICC 0.69-0.83), w ith no discernible differences among the three ICCs, Method errors, assesse d by the standard error of the measurement (S.E.M.) and S.E.M. %, were tow. The Bland & Altman graphs and analyses indicated no significant systematic bias in the data, In conclusion, measurements of eccentric ankle dorsiflex or muscle performance in young healthy individuals using the Biodex are hig hly reliable.