Original articleTest-Retest Reliability of Isokinetic Knee Extension and Flexion
Section snippets
Methods
Subjects were included in the study if they participated in elite, subelite, or recreational running-related sports at least twice weekly and, at the time of testing, were participating fully in their planned sports training and/or competition. Exclusion criteria included having sustained a lower limb, pelvic, or back injury in the past 6 months that prevented them from participating in their training for more than 1 week, or if they had any neurologic or systemic disease affecting a lower
Results
Twenty healthy subjects (13 men, 7 women) volunteered for this study. Two men (aged 22y and 35y) did not attend the second session because of a soccer-related injury and a work commitment, respectively, and were excluded from the study. The mean age ± SD for the 11 men was 20±1 years and for the women it was 22±3 years. The mean body mass index ± SD for the men was 23.0±2.5kg/m2 and for the women was 22.3±2.6kg/m2. Two of the men were experienced in resistance training but none of the subjects
Discussion
Our subjects formed a heterogeneous group with regard to sex, experience with strength testing and training, and sports backgrounds and were a reflection of patients most commonly seen by clinicians at the community level. The men were generally stronger than the women, as is apparent from the Bland-Altman plots (see fig 1). No other systematic differences existed between the sexes, however, thus we pooled the reliability statistics for the men and the women.
Correlations from .50 to .69 have
Conclusions
With the Kin-Com 500H isokinetic dynamometer, the relative reliability for all knee flexion and extension variables at a velocity of 60°/s was very high and was high for the He:Qc, but low for the Hc:Qc. In uninjured subjects, the smallest change that can indicate a real improvement (smallest real difference) ranges from 13 to 34Nm (15%−23%) for peak torque and from 14 to 23J (12%−25%) for work variables. The peak torque ratios are less sensitive in detecting a real change, with the smallest
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Supported by the Physiotherapy Research Trust, School of Physiotherapy, University of Otago (research grant-in-aid).
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.