RELATIVE ERROR ANALYSIS DURING REPRODUCTION OF ISOMETRIC FORCE OF KNEE EXTENSORS IN YOUNG ADULTS

Abstract

This study compared the force reproduction of isometric knee extension at 60°, between the target forces at 30%, 50% and 70% of the maximum voluntary isometric force (MVIF) in young adults. Twenty young males took part in the study. The trials were performed on an instrumented chair developed for the study. Feedback was given to the participants during three trials prior the beginning of data collection in each analyzed target force. Participants performed 10 trials without any feedback for the target force at 30% and 50% of the MVIF and 3 trials for the target force at 70% of MVIF. The relative error decreased as the target force increased. The differences were significant between 30% and 70% (p=0.01) and between 50% and 70% (p=0.03). The reproduction of higher forces during isometric extension of the knee will produce lower relative errors for this specific task.