Reliability of a Reciprocal Test Protocol Performed on the Kinetic Communicator: An Isokinetic Test of Knee Extensor and Flexor Strength

Fri, 12 Sep 2008 00:00:00 EST

Beverly Harding, Tim Black, Annette Bruulsema, Bill Maxwell, Paul W. Stratford

This study tested knee extensor and flexor strength using a reciprocal testing protocol on the Kin-Com isokinetic dynamometer. The purposes were: 1) to identify the variability associated with subjects, repetitions, occasions, and their various interactions; 2) to express the overall measurement error in clinically relevant terms; and 3) advance a strategy for maximizing reliability while simultaneously ensuring that all major sources of measurement error are represented. Fourteen healthy women were tested on two separate occasions (test sessions). On each occasion, measurements of knee extensor and flexor peak torque, average torque, and peak torque angle were gathered for each subject. The results indicated a high overall reliability (range 0.936-0.952) for all measures except peak torque angle (0.630-0.799). Reliability coefficients were consistently lower between occasions than among repetitions, indicating that this type of testing should occur on more than one occasion so as to include all sources of measurement error. This study has expressed measurement error in clinically relevant terms using a 95% confidence range. The findings indicate that a high reliability for isokinetic leg strength measurements can be achieved using a reciprocal testing protocol on the Kin-Com device.

J Orthop Sports Phys Ther 1988;10(6):218-223.

The Effect of Inter-Trial Rest Interval on the Assessment of Isokinetic Thigh Muscle Torque

Thu, 11 Sep 2008 00:00:00 EST

Annette Bruulsema, Bill Maxwell, Tim Black, Beverly Harding, Paul W. Stratford
The purpose of this study was to examine the effect of two measurement protocols on the reliability of peak isokinetic knee extensor and flexor torques performed at 60°/sec. Isokinetic knee extensor and flexor torques were measured using two test protocols on 16 subjects. The two reciprocal testing protocols consisted of five trials performed with either no rest or a 30-sec rest between trials. Each subject performed both protocols with the order of protocol administration balanced across subjects. The results indicated that the Rest protocol produced average torques which were 5% greater than the No Rest protocol and that higher reliability coefficients were obtained for the Rest protocol. These findings are likely due to a significant linear trend across trials evident with the No Rest protocol. It was also demonstrated that the measurement error calculated for the average of five trials was less than that of a single trial. These findings strongly suggest that a greater measurement precision can be achieved by averaging trials obtained using a rest protocol.

J Orthop Sports Phys Ther 1990;11(8):362-366.

Journal of Orthopaedic & Sports Physical Therapy - Beverly Harding, BSc

Reliability of a Reciprocal Test Protocol Performed on the Kinetic Communicator: An Isokinetic Test of Knee Extensor and Flexor Strength

The Effect of Inter-Trial Rest Interval on the Assessment of Isokinetic Thigh Muscle Torque