Test-retest relative and absolute reliability of knee extensor strength measures and minimal detectable change
BACKGROUND: Few studies have assessed the test-retest reliability of the isokinetic strength at 90°/s and the isometric parameters for knee extensors. OBJECTIVES: To assess the reliability of isokinetic and isometric parameters of knee extensors, and to determine the smallest real difference between...
Saved in:
Published in | Isokinetics and exercise science Vol. 22; no. 1; pp. 17 - 26 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
London, England
SAGE Publications
01.01.2014
|
Subjects | |
Online Access | Get full text |
ISSN | 0959-3020 1878-5913 |
DOI | 10.3233/IES-130522 |
Cover
Summary: | BACKGROUND: Few studies have assessed the test-retest reliability of the isokinetic strength at 90°/s and the isometric parameters for knee extensors.
OBJECTIVES: To assess the reliability of isokinetic and isometric parameters of knee extensors, and to determine the smallest real difference between the test-retest measures.
METHODS: Knee extensor strength was measured twice, 4 to 5 days apart, using a Biodex dynamometer in forty subjects (12 men, 28 women). The protocols consisted of 5 concentric contractions at 90°/s and 5 isometric contractions.
RESULTS: For women, test-retest reliability was very high for isometric and isokinetic peak-torque (ICC
$_{c,1}$
> 0.9), moderate for work (ICC
$_{c,1}$
=0.82) and questionable for angle of peak torque (Angle-PT), mean Angle-PT and rate of torque development(RTD
$_{0-100 ms}$
(ICC < 0.67). The measurement errors were small for all variables, the SEM% ranged between 3.1% to 7.4%, and SRD% from 8.6% to 19.9%, except for RTD
$_{0-100 ms}$
that was the most variable (SEM%=16.4%; SRD=47.5%). No differences were found in Angle-PT and RTD
$_{0-100 ms}$
with regard to sex.
CONCLUSIONS: The isokinetic values obtained at 90°/s and isometric peak-torque for knee extensors are highly repeatable with a standardized test protocol and the SRD values can be used to detect real changes. Alternative strategies of analysis should be developed to improve reliability of Angle-PT and RTD
$_{0-100 ms}$
. Angle-PT and RTD
$_{0-100 ms}$
do not appear affected by gender. |
---|---|
ISSN: | 0959-3020 1878-5913 |
DOI: | 10.3233/IES-130522 |