METROLOGY APPLIED TO THE PRODUCTION OF ISOMETRIC TORQUE OF THE KNEE FLEXOR-EXTENSORS: REPRODUCIBILITY AND RESPONSIVENESS USING A PORTABLE TRACTION DYNAMOMETER

Description

Introduction: Measures of muscle strength and/or torque, limb symmetry (SI) and the ischium/quadriceps ratio (R-I/Q) are widely used in clinical and sports settings. It is crucial to ensure their reproducibility. Objective: To determine reproducibility and responsiveness, using the Dinabang, for aspects of knee flexor-extensor muscle function measured isometrically. Methods: An observational test-retest study with 20 volunteers aged 18 to 59. A Dinabang portable traction dynamometer was used to obtain maximum isometric torque (MIT) measurements. The volunteers were assessed bilaterally for the MITflexors and MITextensors outcomes using the test-retest approach, and the SI and R-I/Q were then calculated. There was a total of one test and two retest measurements, and the assessment procedures were identical for all tests. Relative reproducibility was assessed using the intraclass correlation coefficient (ICC) and absolute reproducibility using the standard error of measurement (SEM). Responsiveness was assessed by the minimum detectable change (MDC). Results: No differences were observed between MIT at different times, neither for MITextensors nor for MITflexors. The SI ICCs of the extensors were moderate and those of the flexors poor; the SEM values indicated high variability (around 85%) and low responsiveness (high MDC values). For R-I/Q, although the ICC was moderate, the SEM was low (with variability of 10.8%) and the responsiveness was acceptable. Conclusions: The MITextensors and R-I/Q measurements showed better reproducibility and responsiveness than those measured by MITflexors and SI, especially for the SI of the flexors

Steps to reproduce

Muscle function was assessed using the Dinabang® portable traction dynamometer (Movi, Montevideo, Uruguay), equipped with an integrated inertial sensor. Maximal isometric torque of the knee extensors and flexors was assessed bilaterally across three assessment sessions. Three 5-s maximal voluntary contractions were performed for each muscle group, with 120-s rest intervals between attempts. The lever arm was measured at each assessment session and entered into the system for torque calculation. Knee assessments were performed using a target angle of 65°, with an acceptable range of 60°–70°. A familiarization procedure consisting of submaximal contractions was performed before the initial test session. The deposited dataset contains the raw measurements obtained during the study. For the analyses reported in the associated manuscript, measurements were classified according to limb dominance, and maximal isometric torque, symmetry index, and hamstring-to-quadriceps ratio were analyzed according to the procedures described in the manuscript.

Institutions

• Universidade Estadual do Oeste do Parana - Campus de Cascavel

  Paraná, Cascavel

Categories

Funders

• National Council for Scientific and Technological Development

  Federal District, Brazil
• Fundação Araucária

  Paraná, Brazil

Licence