Isometric and Isokinetic Torques of the Forearm Pronators and Supinators: Reliability and Interrelationships

This study examined the reliability and interrelationships among isometric and isokinetic measurements of forearm pronation and supination strength. Twenty-one healthy men and 22 healthy women were tested at 0, 60, and 120 deg/sec angular velocities using a Cybex 340 dynamometer. Averaging scores over two test occasions was required to produce acceptable reliability coefficients for each gender (intraclass correlation coefficient > 0.75). Overall, men and women demonstrated similar correlations. Isometric torques were modestly related to isokinetic torques during pronation (r = 0.48–0.72; p < 0.05), but highly related during supination (r = 0.81–0.93; p < 0.01). Torques produced by the dominant arm tended to be highly related to those produced using the nondominant arm (r = 0.68–0.83 during pronation and r = 0.79–0.92 during supination; p < 0.01). The predictive utility of these data should be interpreted with the objective of predicting a range of possible scores rather than a single precise score.