Research article summary (published 5 Dec 2007):

Reliability of isokinetic strength imbalance ratios measured using the Cybex NORM dynamometer.

Full Abstract

The main aim of this study was to examine the absolute and relative reliability of some commonly used strength imbalance indices such as concentric hamstring-to-concentric quadriceps ratio, eccentric hamstring-to-concentric quadriceps ratio and bilateral concentric and eccentric strength ratios. An additional aim was to examine the reliability of the peak torque and work of the knee extensor and flexor muscles measured using the Cybex NORM dynamometer. Eighteen physically active healthy subjects (mean +/- standard deviation, age 23 +/- 3 years, height 176 +/- 5 cm, body mass 74 +/- 8 kg) were tested three times with 96 h between sessions. Peak torque, average work, unilateral and bilateral ratios were determined at 60, 120, 180 and -60 degrees s(-1). Low (0.34) to moderate (0.87) relative reliability (intraclass correlation coefficient, ICC) was found for strength imbalance ratios with eccentric hamstring-to-concentric quadriceps ratio showing the greater ICC (>0.80). High ICC values (0.90-0.98) were found for peak torque and average work. Absolute reliability (standard error of measurement) ranged from 3.2% to 8.7% for strength imbalance ratios and from 4.3% to 7.7% for peak torque and average work measurements. This study established the reliability of the most common strength imbalance ratios and of absolute isokinetic muscle strength assessed using the Cybex NORM.

Author information

Author/s: Impellizzeri, Franco M (FM); Bizzini, Mario (M); Rampinini, Ermanno (E); Cereda, Ferdinando (F); Maffiuletti, Nicola A (NA);

Affiliation: Neuromuscular Research Laboratory, Schulthess Clinic, Zurich, Switzerland. franco.impellizzeri(-atsign-)kws.ch

Journal and publication information

Publication Type: Journal Article

Journal: Clinical physiology and functional imaging (Clin Physiol Funct Imaging), published in England. (Language: eng)

Reference: 2008-Mar; vol 28 (issue 2) : pp 113-9

Dates: Created 2008/02/11; Completed 2008/06/03;

PMID: 18070123, status: MEDLINE (last retrieval date: 2/18/2009, IMS Date: )

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

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MeSH headings (categories)

This article was linked to the MESH Headings shown below.

Adult Analysis of Variance Biomechanics Humans Leg - physiology

Muscle Contraction - physiology Muscle Strength - physiology Muscle, Skeletal - physiology Reproducibility of Results Torque

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