Cargando…
A simple test of muscle coactivation estimation using electromyography
In numerous motor tasks, muscles around a joint act coactively to generate opposite torques. A variety of indexes based on electromyography signals have been presented in the literature to quantify muscle coactivation. However, it is not known how to estimate it reliably using such indexes. The goal...
Autores principales: | , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Sociedade Brasileira de Medicina Tropical
2012
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3854180/ https://www.ncbi.nlm.nih.gov/pubmed/22641413 http://dx.doi.org/10.1590/S0100-879X2012007500092 |
_version_ | 1782294749397385216 |
---|---|
author | Ervilha, U.F. Graven-Nielsen, T. Duarte, M. |
author_facet | Ervilha, U.F. Graven-Nielsen, T. Duarte, M. |
author_sort | Ervilha, U.F. |
collection | PubMed |
description | In numerous motor tasks, muscles around a joint act coactively to generate opposite torques. A variety of indexes based on electromyography signals have been presented in the literature to quantify muscle coactivation. However, it is not known how to estimate it reliably using such indexes. The goal of this study was to test the reliability of the estimation of muscle coactivation using electromyography. Isometric coactivation was obtained at various muscle activation levels. For this task, any coactivation measurement/index should present the maximal score (100% of coactivation). Two coactivation indexes were applied. In the first, the antagonistic muscle activity (the lower electromyographic signal between two muscles that generate opposite joint torques) is divided by the mean between the agonistic and antagonistic muscle activations. In the second, the ratio between antagonistic and agonistic muscle activation is calculated. Moreover, we computed these indexes considering different electromyographic amplitude normalization procedures. It was found that the first algorithm, with all signals normalized by their respective maximal voluntary coactivation, generates the index closest to the true value (100%), reaching 92 ± 6%. In contrast, the coactivation index value was 82 ± 12% when the second algorithm was applied and the electromyographic signal was not normalized (P < 0.04). The new finding of the present study is that muscle coactivation is more reliably estimated if the EMG signals are normalized by their respective maximal voluntary contraction obtained during maximal coactivation prior to dividing the antagonistic muscle activity by the mean between the agonistic and antagonistic muscle activations. |
format | Online Article Text |
id | pubmed-3854180 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | Sociedade Brasileira de Medicina Tropical |
record_format | MEDLINE/PubMed |
spelling | pubmed-38541802013-12-16 A simple test of muscle coactivation estimation using electromyography Ervilha, U.F. Graven-Nielsen, T. Duarte, M. Braz J Med Biol Res Short Communication In numerous motor tasks, muscles around a joint act coactively to generate opposite torques. A variety of indexes based on electromyography signals have been presented in the literature to quantify muscle coactivation. However, it is not known how to estimate it reliably using such indexes. The goal of this study was to test the reliability of the estimation of muscle coactivation using electromyography. Isometric coactivation was obtained at various muscle activation levels. For this task, any coactivation measurement/index should present the maximal score (100% of coactivation). Two coactivation indexes were applied. In the first, the antagonistic muscle activity (the lower electromyographic signal between two muscles that generate opposite joint torques) is divided by the mean between the agonistic and antagonistic muscle activations. In the second, the ratio between antagonistic and agonistic muscle activation is calculated. Moreover, we computed these indexes considering different electromyographic amplitude normalization procedures. It was found that the first algorithm, with all signals normalized by their respective maximal voluntary coactivation, generates the index closest to the true value (100%), reaching 92 ± 6%. In contrast, the coactivation index value was 82 ± 12% when the second algorithm was applied and the electromyographic signal was not normalized (P < 0.04). The new finding of the present study is that muscle coactivation is more reliably estimated if the EMG signals are normalized by their respective maximal voluntary contraction obtained during maximal coactivation prior to dividing the antagonistic muscle activity by the mean between the agonistic and antagonistic muscle activations. Sociedade Brasileira de Medicina Tropical 2012-06-01 /pmc/articles/PMC3854180/ /pubmed/22641413 http://dx.doi.org/10.1590/S0100-879X2012007500092 Text en http://creativecommons.org/licenses/by-nc/3.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Short Communication Ervilha, U.F. Graven-Nielsen, T. Duarte, M. A simple test of muscle coactivation estimation using electromyography |
title | A simple test of muscle coactivation estimation using electromyography |
title_full | A simple test of muscle coactivation estimation using electromyography |
title_fullStr | A simple test of muscle coactivation estimation using electromyography |
title_full_unstemmed | A simple test of muscle coactivation estimation using electromyography |
title_short | A simple test of muscle coactivation estimation using electromyography |
title_sort | simple test of muscle coactivation estimation using electromyography |
topic | Short Communication |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3854180/ https://www.ncbi.nlm.nih.gov/pubmed/22641413 http://dx.doi.org/10.1590/S0100-879X2012007500092 |
work_keys_str_mv | AT ervilhauf asimpletestofmusclecoactivationestimationusingelectromyography AT gravennielsent asimpletestofmusclecoactivationestimationusingelectromyography AT duartem asimpletestofmusclecoactivationestimationusingelectromyography AT ervilhauf simpletestofmusclecoactivationestimationusingelectromyography AT gravennielsent simpletestofmusclecoactivationestimationusingelectromyography AT duartem simpletestofmusclecoactivationestimationusingelectromyography |