title: Inter-machine reliability of the Biodex and Cybex isokinetic dynamometers for knee flexor/extensor isometric, concentric and eccentric tests.
abstract: OBJECTIVE
  To assess the inter-machine reliability of the Biodex System 3 Pro and Cybex Humac Norm Model 770 dynamometers for knee extensor and knee flexor peak torque measurements in isometric, concentric and eccentric tests.
  
  
  METHODS
  Randomized/crossover.
  
  
  METHODS
  Exercise Research Laboratory, Federal University of Rio Grande do Sul (Brazil).
  
  
  METHODS
  25 healthy male subjects.
  
  
  METHODS
  Isometric, concentric and eccentric knee extensor and knee flexor peak torques recorded in the same test procedure performed on both isokinetic dynamometers. One-way ANOVA, intraclass correlation coefficient (ICC), standard error of measurement (SEM) and coefficient of variation (CV) were used to verify significant differences, relative and absolute reliability between devices.
  
  
  RESULTS
  No significant differences were found between tests performed on Biodex and Cybex (p > 0.05). ICC values indicated a high to very high reproducibility for isometric, concentric and eccentric peak torques (0.88-0.92), and moderate to high reliability for agonist-antagonist strength ratios (0.62-0.73). Peak torque did not show great difference between dynamometers for SEM (3.72-11.27 Nm) and CV (5.27-7.77%). Strength ratios presented CV values of 8.57-10.72%.
  
  
  CONCLUSIONS
  Maximal knee extensor and knee flexor tests performed in isometric (60° of knee flexion), concentric and eccentric modes at 60°/s in Biodex and Cybex dynamometers present similar values.
authors.affiliation: Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750, Bairro Jardim Botânico, CEP: 90690-200 Porto Alegre, RS, Brazil.
authors.forename: João Breno
authors.initials: JB
authors.lastname: de Araujo Ribeiro Alvares
authors.affiliation: Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750, Bairro Jardim Botânico, CEP: 90690-200 Porto Alegre, RS, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Rodrigues
authors.affiliation: Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750, Bairro Jardim Botânico, CEP: 90690-200 Porto Alegre, RS, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: de Azevedo Franke
authors.affiliation: Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750, Bairro Jardim Botânico, CEP: 90690-200 Porto Alegre, RS, Brazil.
authors.forename: Bruna Gonçalves Cordeiro
authors.initials: BG
authors.lastname: da Silva
authors.affiliation: Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750, Bairro Jardim Botânico, CEP: 90690-200 Porto Alegre, RS, Brazil.
authors.forename: Ronei Silveira
authors.initials: RS
authors.lastname: Pinto
authors.affiliation: Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750, Bairro Jardim Botânico, CEP: 90690-200 Porto Alegre, RS, Brazil.
authors.forename: Marco Aurélio
authors.initials: MA
authors.lastname: Vaz
authors.affiliation: Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750, Bairro Jardim Botânico, CEP: 90690-200 Porto Alegre, RS, Brazil. Electronic address: bmbaroni@yahoo.com.br.
authors.forename: Bruno Manfredini
authors.initials: BM
authors.lastname: Baroni
mesh_terms: D000328:Adult; D004867:Equipment Design; D005080:Exercise Test; D006801:Humans; D007719:Knee Joint; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D053581:Muscle Strength Dynamometer / Q000592:standards*; D018482:Muscle, Skeletal / Q000502:physiology; D052097:Quadriceps Muscle / Q000502:physiology*; D015203:Reproducibility of Results; D055815:Young Adult
keywords: Hamstring; Isokinetic dynamometry; Quadriceps; Test–retest