Abstract

Aim of the study was to ascertain the reliability of isokinetic strength measurements in a population of post-poliomyelitis subjects (PPS). 8 subjects were evaluated, on a weekly basis for 3 wks at the same time of day. During each test session knee flexors and extensors (bilaterally, where possible) were evaluated. Subjects became familiar with the equipment prior to recording 3 maximal contractions at 4 test velocities (1.05, 2.09, 3.14, 4.18 rads/s). A 2-min rest period was allowed between sets of contractions. Variables of peak torque, angle of peak torque, torque at specific joint angles (0.79 and 1.05 rads), total contractile work, maximum power, and average power were measured on-line with the Cybex IIa system using a commercially available software package. In both muscle groups, all variables were significantly weaker on the most affected, but testable limb in subjects where both limbs could be tested. Peak torque and total work of the quadriceps were observed to decrease with increasing velocity of movement. Effects of velocity were less apparent in the hamstrings. Average and maximum power developed by knee extensors and flexors increased with increasing velocity of movement. Reliability of performance over 3 test sessions was confirmed by the intraclass correlation coefficient (ICC) values derived from the univariate ANOVAs calculated for each of the above variables (>0.80). This study demonstrated that a Cybex II isokinetic device is a reliable means to evaluate strength in persons with PPS. Verf.-Referat (gekuerzt)