Abstract
The purpose of this study was to examine angular velocity fluctuations during isokinetic eccentric movements. The Biodex and KinCom isokinetic dynamometers were used for data recording and analysis. Kinematic analysis was performed to calculate the criterion angular velocity against which the velocity recorded by the dynamometer was tested. The period of constant velocity expressed as a percentage of the whole range of motion ranged between 76.5 and 20.9% for the Biodex and for preset velocities ranging from 30 to 150°/s. The respective values for the KinCom were 66.7–28.1% from 30 to 250°/s. It was also found that the dynamometers' angular velocity measurements are only approximations of the actual angular velocity. In conclusion the results of this study indicate that at high velocities and in cases where the range of motion is limited, the effects of angular velocity to various mechanical parameters such as peak moment, power, work, etc. have to be considered or the measurements have to be limited only to constant velocity periods throughout the range of motion.