Changes in FDB and soleus muscle activity after a train of stimuli during upright stance
Autor(a) principal: | |
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Data de Publicação: | 2012 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Brazilian Journal of Physical Therapy |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1413-35552012000300009 |
Resumo: | BACKGROUND: Evidence of self-sustained muscle activation following a brief electrical stimulation has been reported in the literature for certain muscles. OBJECTIVES: This report shows that the foot muscle (Flexor Digitorum Brevis - FDB) shows a self-sustained increase in muscle activity during upright stance in some subjects following a train of stimuli to the tibial nerve. METHODS: Healthy subjects were requested to stand upright and surface EMG electrodes were placed on the FDB, Soleus and Tibialis Anterior muscles. After background muscle activity (BGA) acquisition, a 50 Hz train of stimuli was applied to the tibial nerve at the popliteal fossa. The root mean square values (RMS) of the BGA and the post-stimulus muscle activation were computed. RESULTS: There was a 13.8% average increase in the FDB muscle EMG amplitude with respect to BGA after the stimulation was turned off. The corresponding post-stimulus Soleus EMG activity decreased by an average of 9.2%. We hypothesize that the sustained contraction observed in the FDB following stimulus may be evidence of persistent inward currents (PIC) generated in FDB spinal motoneurons. The post-stimulus decrease in soleus activity may have occurred due to the action of inhibitory interneurons caused by the PICs, which were triggered by the stimulus train. CONCLUSIONS: These sustained post-stimulation changes in postural muscle activity, found in different levels in different subjects, may be part of a set of possible responses that contribute to overall postural control. |
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Brazilian Journal of Physical Therapy |
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Changes in FDB and soleus muscle activity after a train of stimuli during upright stancephysical therapyposturefoot; humanelectromyographymotor activityBACKGROUND: Evidence of self-sustained muscle activation following a brief electrical stimulation has been reported in the literature for certain muscles. OBJECTIVES: This report shows that the foot muscle (Flexor Digitorum Brevis - FDB) shows a self-sustained increase in muscle activity during upright stance in some subjects following a train of stimuli to the tibial nerve. METHODS: Healthy subjects were requested to stand upright and surface EMG electrodes were placed on the FDB, Soleus and Tibialis Anterior muscles. After background muscle activity (BGA) acquisition, a 50 Hz train of stimuli was applied to the tibial nerve at the popliteal fossa. The root mean square values (RMS) of the BGA and the post-stimulus muscle activation were computed. RESULTS: There was a 13.8% average increase in the FDB muscle EMG amplitude with respect to BGA after the stimulation was turned off. The corresponding post-stimulus Soleus EMG activity decreased by an average of 9.2%. We hypothesize that the sustained contraction observed in the FDB following stimulus may be evidence of persistent inward currents (PIC) generated in FDB spinal motoneurons. The post-stimulus decrease in soleus activity may have occurred due to the action of inhibitory interneurons caused by the PICs, which were triggered by the stimulus train. CONCLUSIONS: These sustained post-stimulation changes in postural muscle activity, found in different levels in different subjects, may be part of a set of possible responses that contribute to overall postural control.Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia 2012-06-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S1413-35552012000300009Brazilian Journal of Physical Therapy v.16 n.3 2012reponame:Brazilian Journal of Physical Therapyinstname:Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia (ABRAPG-FT)instacron:ABRAPG-FT10.1590/S1413-35552012005000024info:eu-repo/semantics/openAccessOkai,Liria A.Kohn,André F.eng2012-07-11T00:00:00Zoai:scielo:S1413-35552012000300009Revistahttps://www.scielo.br/j/rbfis/https://old.scielo.br/oai/scielo-oai.phpcontato@rbf-bjpt.org.br||contato@rbf-bjpt.org.br1809-92461413-3555opendoar:2012-07-11T00:00Brazilian Journal of Physical Therapy - Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia (ABRAPG-FT)false |
dc.title.none.fl_str_mv |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance |
title |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance |
spellingShingle |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance Okai,Liria A. physical therapy posture foot; human electromyography motor activity |
title_short |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance |
title_full |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance |
title_fullStr |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance |
title_full_unstemmed |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance |
title_sort |
Changes in FDB and soleus muscle activity after a train of stimuli during upright stance |
author |
Okai,Liria A. |
author_facet |
Okai,Liria A. Kohn,André F. |
author_role |
author |
author2 |
Kohn,André F. |
author2_role |
author |
dc.contributor.author.fl_str_mv |
Okai,Liria A. Kohn,André F. |
dc.subject.por.fl_str_mv |
physical therapy posture foot; human electromyography motor activity |
topic |
physical therapy posture foot; human electromyography motor activity |
description |
BACKGROUND: Evidence of self-sustained muscle activation following a brief electrical stimulation has been reported in the literature for certain muscles. OBJECTIVES: This report shows that the foot muscle (Flexor Digitorum Brevis - FDB) shows a self-sustained increase in muscle activity during upright stance in some subjects following a train of stimuli to the tibial nerve. METHODS: Healthy subjects were requested to stand upright and surface EMG electrodes were placed on the FDB, Soleus and Tibialis Anterior muscles. After background muscle activity (BGA) acquisition, a 50 Hz train of stimuli was applied to the tibial nerve at the popliteal fossa. The root mean square values (RMS) of the BGA and the post-stimulus muscle activation were computed. RESULTS: There was a 13.8% average increase in the FDB muscle EMG amplitude with respect to BGA after the stimulation was turned off. The corresponding post-stimulus Soleus EMG activity decreased by an average of 9.2%. We hypothesize that the sustained contraction observed in the FDB following stimulus may be evidence of persistent inward currents (PIC) generated in FDB spinal motoneurons. The post-stimulus decrease in soleus activity may have occurred due to the action of inhibitory interneurons caused by the PICs, which were triggered by the stimulus train. CONCLUSIONS: These sustained post-stimulation changes in postural muscle activity, found in different levels in different subjects, may be part of a set of possible responses that contribute to overall postural control. |
publishDate |
2012 |
dc.date.none.fl_str_mv |
2012-06-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1413-35552012000300009 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1413-35552012000300009 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S1413-35552012005000024 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia |
publisher.none.fl_str_mv |
Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia |
dc.source.none.fl_str_mv |
Brazilian Journal of Physical Therapy v.16 n.3 2012 reponame:Brazilian Journal of Physical Therapy instname:Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia (ABRAPG-FT) instacron:ABRAPG-FT |
instname_str |
Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia (ABRAPG-FT) |
instacron_str |
ABRAPG-FT |
institution |
ABRAPG-FT |
reponame_str |
Brazilian Journal of Physical Therapy |
collection |
Brazilian Journal of Physical Therapy |
repository.name.fl_str_mv |
Brazilian Journal of Physical Therapy - Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia (ABRAPG-FT) |
repository.mail.fl_str_mv |
contato@rbf-bjpt.org.br||contato@rbf-bjpt.org.br |
_version_ |
1754575949180960768 |