Abstract
The purpose of this study was to investigate the concentric and eccentric peak torque reliability of the Biodex B-2000, Kinetic Communicator, and Lido isokinetic dynamometers when testing the shoulder internal and external rotators. The subjects were 22 males with no previous shoulder pathology. Each subject completed two test sessions for each isokinetic dynamometer. The right upper extremity was tested at 120°/s through a 140° arc of motion with the shoulder in 90° of abduction. After a warm-up of three sub-maximal repetitions and 1 maximal repetition, five maximal repetitions were completed in either the concentric or eccentric mode. A 5-min rest period lapsed and then the second test mode was completed. Six days later, the subjects were tested in the reverse order. This procedure was completed for each isokinetic dynamometer. Four one-way analyses of variance with repeated measures were used to compare peak torque values of shoulder internal and external rotation in each test mode. The F-values indicated significant differences in concentric and eccentric internal rotation and eccentric external rotation. Therefore indicating that comparisons of peak torque values should not be made between different isokinetic dynamometers. Means, standard error of measurement (SEM), and intraclass correlations (ICC) were calculated for each dynamometer in each test mode. The ICCs for concentric peak torque were generally higher than those of eccentric peak torque, but lower than those reported by previous researchers. Of the many variables that can impact isokinetic testing, position may have been the most influential in this study. It is possible that impingement of the shoulder rotators occured with the shoulder in 90 of abduction. Perhaps another test position would have yielded more consistent results. The presence of delayed onset muscle soreness may have also influenced this study. Copyright