Evidence map›Paper›PMID 39462400›Full record

ArticleBiomedical engineering online2024

The probability density function of the surface electromyogram and its dependence on contraction force in the vastus lateralis.

Javier Rodriguez-Falces, Armando Malanda, Cristina Mariscal, Silvia Recalde, Javier Navallas

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Article in Biomedical engineering online, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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1citing papers in PubMed
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1 · What the graph read from it

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3 · Its place in the literature

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1 citing paper in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

5 authors.

Javier Rodriguez-FalcesDepartment of Electrical and Electronical Engineering, Public University of Navarra D.I.E.E., Campus de Arrosadía S/N, 31006, Pamplona, Spain. javier.rodriguez@unavarra.es.
Armando MalandaDepartment of Electrical and Electronical Engineering, Public University of Navarra D.I.E.E., Campus de Arrosadía S/N, 31006, Pamplona, Spain.
Cristina MariscalDepartment of Clinical Neurophysiology, Hospital Complex of Navarra, Pamplona, Spain.
Silvia RecaldeDepartment of Electrical and Electronical Engineering, Public University of Navarra D.I.E.E., Campus de Arrosadía S/N, 31006, Pamplona, Spain.
Javier NavallasDepartment of Electrical and Electronical Engineering, Public University of Navarra D.I.E.E., Campus de Arrosadía S/N, 31006, Pamplona, Spain.

Funding

This work has been supported by the project PID2022-136620OB-I00 financed by Spanish Ministry of Science and Innovation MCIN/AEI/10.13039/501100011033/FEDER,UE. PID2022-136620OB-I00
6 · The paper itself

Abstract

introductionThe probability density function (PDF) of the surface electromyogram (sEMG) depends on contraction force. This dependence, however, has so far been investigated by having the subject generate force at a few fixed percentages of MVC. Here, we examined how the shape of the sEMG PDF changes with contraction force when this force was gradually increased from zero.

methodsVoluntary surface EMG signals were recorded from the vastus lateralis of healthy subjects as force was increased in a continuous manner vs. in a step-wise fashion. The sEMG filling process was examined by measuring the EMG filling factor, computed from the non-central moments of the rectified sEMG signal.

results(1) In 84% of the subjects, as contraction force increased from 0 to 10% MVC, the sEMG PDF shape oscillated back and forth between the semi-degenerate and the Gaussian distribution. (2) The PDF-force relation varied greatly among subjects for forces between 0 and ~ 10% MVC, but this variability was largely reduced for forces above 10% MVC. (3) The pooled analysis showed that, as contraction force gradually increased, the sEMG PDF evolved rapidly from the semi-degenerate towards the Laplacian distribution from 0 to 5% MVC, and then more slowly from the Laplacian towards the Gaussian distribution for higher forces.

conclusionsThe study demonstrated that the dependence of the sEMG PDF shape on contraction force can only be reliably assessed by gradually increasing force from zero, and not by performing a few constant-force contractions. The study also showed that the PDF-force relation differed greatly among individuals for contraction forces below 10% MVC, but this variability was largely reduced when force increased above 10% MVC.

Indexed as

ElectromyographyMuscle ContractionProbabilityQuadriceps MuscleAdultBiomechanical PhenomenaFemaleHumansMaleSignal Processing, Computer-AssistedYoung AdultFilling factorGaussianityInterference pattern analysisProbability density function (PDF)Surface EMG

Identifiers

PMID39462400
PMCPMC11515092

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