Correction of Isokinetic and Isometric Torque Recordings for the Effects of Gravity

Abstract

The effect of gravity on neuromuscular performance should be measured in most research applications and in some clinical assessments. Comparing recorded values of maximal torque generated by knee extensor and flexor muscles using the Cybex® II* isokinetic dynamometer shows that gravity significantly affects the recordings, resulting in an overestimation of active flexor muscle torque and an underestimation of active extensor muscle torque.^1,2 During both endurance and high velocity testing, the relative contribution of gravity to recorded torque values becomes increasingly large as active torque generation decreases.^1,2 The Cybex® II dynamometer with dual channel recorder allows one to record and measure isometric and isokinetic torque and also the specific joint angle at which the torque is produced. One of the advantages of such a system is that the effect of gravity on measured torque may be calculated.