ERRORS IN THE USE OF ISOKINETIC SOFTWARE AND SYSTEMS

In the literature a good reliability of isokinetic measurements is rep orted. In spite of these reports high variations of the peak torque an d work values were registered when testing 24 patients with low back p ain, using a CYBEX TR isokinetic trunk rotation apparatus. After a 3 w eek's training the patients force (peak torque) increased in the avera ge between 10.7 p.c. (SD+/-26.4) and 23.2 p.c. (SD+/-63.8), correspond ing to the test-velocity. Seven of the 24 patients improved or deterio rated more than 30 p.c. Analysing the parameters which could interfere with the results there was found a discrepancy between the original C YBEX software and the German Iso-Kin 4.0 software. The Isokin 4.0 does not warm up and calibrate the isokinetic apparatus daily. Investigati ons with definite weights showed that the values for peak torque are 4 0-50 m higher when using the Iso-Kin 4.0 software in comparison to the original CYBEX software. Furthermore there are a lot of other paramet ers such as acceleration of the body, psychological alterations, pain, motivation, learning effects, and artificial oscillations of the regi strated curve, which can affect the results even when using the origin al CYBEX software.