Comparison of Open Kinetic Chain Knee and Hip Extension to Closed Kinetic Chain Leg Press Performance

Abstract

The purposes of this study were to determine the relationship of isokinetic quadriceps and hip extensor peak torque to isokinetic leg press peak torque and to determine the influence of hip position (seated vs. supine) on leg press peak torque. Forty subjects (20 males and 20 females) were tested bilaterally on the isokinetic dynamometer. Subjects were tested during knee extension, hip extension, seated leg press, and supine leg press. Intraclass correlation coefficient and standard error of measurement values revealed acceptable reliability for all tests. An analysis of variance revealed significant dominant versus nondominant differences in all tests except hip extension. A repeated measures analysis of variance revealed no significant difference between seated and supine leg press peak torque. Finally, stepwise regression revealed a significant relationship between knee extension and leg press peak torques, with hip extension adding only minimally to the explained variance. These data suggest that knee extension and leg press peak torque assess similar muscle performance characteristics. Further research involving electromyographic analysis is recommended to determine the influence of other muscles on leg press force performance.