Abstract

Using an isokinetic dynamometer (CYBEX II) moment-angle-angular velocity relationships for plantar flexion were determined in 12 subjects. During isometric contractions, the time elapsed between onset of contraction and the instant that the moment attained 90 of its maximum amounted to 330 ms on average. This is more than the time elapsed before the peak moment is reached at high angular velocities. For instance, at an angular velocity of 90 degrees per sec., the peak moment was attained 280 ms after the start of contraction. Based on the results it is questioned if isokinetic measurements give information about intrinsic muscle properties. Because of a difference in measurement procedure, the moment-angle-angular velocity relationships for isokinetic plantar flexion cannot be compared with force-length relationships of isolated muscles. Verf.-Referat