Test-retest reliability of isokinetic knee extension and flexion.
OBJECTIVE
To assess reliability of isokinetic peak torque and work for knee flexion and extension.


METHODS
Single-group test-retest.


METHODS
University laboratory.


METHODS
Eleven men and 7 women (mean age, 21 y).


METHODS
Not applicable.


METHODS
Peak torque and work for concentric and eccentric knee extension and flexion were recorded at 60 degrees/s for 3 trials on 2 occasions. Intraclass correlation coefficient model 3,1 (ICC(3,1)), standard error (SE) of measurements, and smallest real differences were calculated for the maximum and for the mean peak torque and work of the 3 repetitions.


RESULTS
Relative reliability was "very high" for peak torque and work (ICC range, >.90). The SE measurements ranged between 5% and 10% of the initial values for both peak torque and work. The smallest change that indicates a real improvement for a single subject (smallest real differences) ranged from 12% to 25% for peak torque and work variables and from 25% to 30% for the peak torque ratios.


CONCLUSIONS
Isokinetic concentric and eccentric knee extensor and flexor strength variables are reliable when measured by the same examiner in asymptomatic subjects.
Sole
Gisela
G
Centre of Physiotherapy Research at the School of Physiotherapy, University of Otago, Dunedin, New Zealand. gisela.sole@otago.ac.nz
Hamrén
Jonas
J
Milosavljevic
Stephan
S
Nicholson
Helen
H
Sullivan
S John
SJ
D000328:Adult; D001696:Biomechanical Phenomena; D005080:Exercise Test; D005260:Female; D006801:Humans; D007719:Knee Joint; D008297:Male; D009068:Movement; D009119:Muscle Contraction; D018482:Muscle, Skeletal; D015203:Reproducibility of Results; D019415:Torque