Inter-individual variability in the torque-related patterns of responses for mechanomyographic amplitude and mean power frequency

Eric D. Ryan, Joel T. Cramer, Terry J. Housh, Travis W. Beck, Trent J. Herda, Michael J. Hartman

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

The purpose of this study was to examine the inter-individual variability for the patterns of responses for mechanomyographic (MMG) amplitude and mean power frequency (MPF) versus isometric torque in lower-strength (LS) and higher-strength (HS) individuals. Twelve participants (mean ± S.D. age = 25 + 4 years) performed two isometric maximal voluntary contractions (MVCs) before and after completing nine submaximal step muscle actions (15%, 25%, 35%, 45%, 55%, 65%, 75%, 85%, and 95% MVC) of the right leg extensors. MMG signals were recorded from the vastus lateralis muscle, and MMG amplitude and MPF values were computed for each corresponding percentage of the MVC. Polynomial regression analyses indicated that the composite MMG amplitude versus isometric torque relationship was best fit with a linear model (r2 = 0.980) for the LS group and a cubic model (r2 = 0.994) for the HS group. The composite MMG MPF versus isometric torque relationships were best fit with linear models for both the LS (r2 = 0.529) and HS (r2 = 0.591) groups. However, only 66% of the individuals exhibited the same linear MMG amplitude patterns as the composite relationship for the LS group, whereas only 33% of the individual relationships were cubic for the HS group. Only one subject exhibited a positive linear (r2 = 0.681) relationship for the MMGMPF versus isometric torque relationship for either the LS or HS groups. These findings suggested that strength differences do not affect the patterns of responses for MMG amplitude or MPF. The lack of consistency between the individual and composite patterns of responses suggested some degree of inter-individual variability. Therefore, future studies should examine the individual patterns of response to draw conclusions about motor control strategies.

Original languageEnglish (US)
Pages (from-to)212-219
Number of pages8
JournalJournal of Neuroscience Methods
Volume161
Issue number2
DOIs
StatePublished - Apr 15 2007

Fingerprint

Torque
Linear Models
Muscles
Quadriceps Muscle
Leg
Regression Analysis

Keywords

  • Mechanomyography
  • Motor unit firing rate
  • Motor unit recruitment
  • Muscle strength
  • Polynomial regression

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Inter-individual variability in the torque-related patterns of responses for mechanomyographic amplitude and mean power frequency. / Ryan, Eric D.; Cramer, Joel T.; Housh, Terry J.; Beck, Travis W.; Herda, Trent J.; Hartman, Michael J.

In: Journal of Neuroscience Methods, Vol. 161, No. 2, 15.04.2007, p. 212-219.

Research output: Contribution to journalArticle

Ryan, Eric D. ; Cramer, Joel T. ; Housh, Terry J. ; Beck, Travis W. ; Herda, Trent J. ; Hartman, Michael J. / Inter-individual variability in the torque-related patterns of responses for mechanomyographic amplitude and mean power frequency. In: Journal of Neuroscience Methods. 2007 ; Vol. 161, No. 2. pp. 212-219.
@article{b88d25ee0ae64e2b83cae7f31413b057,
title = "Inter-individual variability in the torque-related patterns of responses for mechanomyographic amplitude and mean power frequency",
abstract = "The purpose of this study was to examine the inter-individual variability for the patterns of responses for mechanomyographic (MMG) amplitude and mean power frequency (MPF) versus isometric torque in lower-strength (LS) and higher-strength (HS) individuals. Twelve participants (mean ± S.D. age = 25 + 4 years) performed two isometric maximal voluntary contractions (MVCs) before and after completing nine submaximal step muscle actions (15{\%}, 25{\%}, 35{\%}, 45{\%}, 55{\%}, 65{\%}, 75{\%}, 85{\%}, and 95{\%} MVC) of the right leg extensors. MMG signals were recorded from the vastus lateralis muscle, and MMG amplitude and MPF values were computed for each corresponding percentage of the MVC. Polynomial regression analyses indicated that the composite MMG amplitude versus isometric torque relationship was best fit with a linear model (r2 = 0.980) for the LS group and a cubic model (r2 = 0.994) for the HS group. The composite MMG MPF versus isometric torque relationships were best fit with linear models for both the LS (r2 = 0.529) and HS (r2 = 0.591) groups. However, only 66{\%} of the individuals exhibited the same linear MMG amplitude patterns as the composite relationship for the LS group, whereas only 33{\%} of the individual relationships were cubic for the HS group. Only one subject exhibited a positive linear (r2 = 0.681) relationship for the MMGMPF versus isometric torque relationship for either the LS or HS groups. These findings suggested that strength differences do not affect the patterns of responses for MMG amplitude or MPF. The lack of consistency between the individual and composite patterns of responses suggested some degree of inter-individual variability. Therefore, future studies should examine the individual patterns of response to draw conclusions about motor control strategies.",
keywords = "Mechanomyography, Motor unit firing rate, Motor unit recruitment, Muscle strength, Polynomial regression",
author = "Ryan, {Eric D.} and Cramer, {Joel T.} and Housh, {Terry J.} and Beck, {Travis W.} and Herda, {Trent J.} and Hartman, {Michael J.}",
year = "2007",
month = "4",
day = "15",
doi = "10.1016/j.jneumeth.2006.11.007",
language = "English (US)",
volume = "161",
pages = "212--219",
journal = "Journal of Neuroscience Methods",
issn = "0165-0270",
publisher = "Elsevier",
number = "2",

}

TY - JOUR

T1 - Inter-individual variability in the torque-related patterns of responses for mechanomyographic amplitude and mean power frequency

AU - Ryan, Eric D.

AU - Cramer, Joel T.

AU - Housh, Terry J.

AU - Beck, Travis W.

AU - Herda, Trent J.

AU - Hartman, Michael J.

PY - 2007/4/15

Y1 - 2007/4/15

N2 - The purpose of this study was to examine the inter-individual variability for the patterns of responses for mechanomyographic (MMG) amplitude and mean power frequency (MPF) versus isometric torque in lower-strength (LS) and higher-strength (HS) individuals. Twelve participants (mean ± S.D. age = 25 + 4 years) performed two isometric maximal voluntary contractions (MVCs) before and after completing nine submaximal step muscle actions (15%, 25%, 35%, 45%, 55%, 65%, 75%, 85%, and 95% MVC) of the right leg extensors. MMG signals were recorded from the vastus lateralis muscle, and MMG amplitude and MPF values were computed for each corresponding percentage of the MVC. Polynomial regression analyses indicated that the composite MMG amplitude versus isometric torque relationship was best fit with a linear model (r2 = 0.980) for the LS group and a cubic model (r2 = 0.994) for the HS group. The composite MMG MPF versus isometric torque relationships were best fit with linear models for both the LS (r2 = 0.529) and HS (r2 = 0.591) groups. However, only 66% of the individuals exhibited the same linear MMG amplitude patterns as the composite relationship for the LS group, whereas only 33% of the individual relationships were cubic for the HS group. Only one subject exhibited a positive linear (r2 = 0.681) relationship for the MMGMPF versus isometric torque relationship for either the LS or HS groups. These findings suggested that strength differences do not affect the patterns of responses for MMG amplitude or MPF. The lack of consistency between the individual and composite patterns of responses suggested some degree of inter-individual variability. Therefore, future studies should examine the individual patterns of response to draw conclusions about motor control strategies.

AB - The purpose of this study was to examine the inter-individual variability for the patterns of responses for mechanomyographic (MMG) amplitude and mean power frequency (MPF) versus isometric torque in lower-strength (LS) and higher-strength (HS) individuals. Twelve participants (mean ± S.D. age = 25 + 4 years) performed two isometric maximal voluntary contractions (MVCs) before and after completing nine submaximal step muscle actions (15%, 25%, 35%, 45%, 55%, 65%, 75%, 85%, and 95% MVC) of the right leg extensors. MMG signals were recorded from the vastus lateralis muscle, and MMG amplitude and MPF values were computed for each corresponding percentage of the MVC. Polynomial regression analyses indicated that the composite MMG amplitude versus isometric torque relationship was best fit with a linear model (r2 = 0.980) for the LS group and a cubic model (r2 = 0.994) for the HS group. The composite MMG MPF versus isometric torque relationships were best fit with linear models for both the LS (r2 = 0.529) and HS (r2 = 0.591) groups. However, only 66% of the individuals exhibited the same linear MMG amplitude patterns as the composite relationship for the LS group, whereas only 33% of the individual relationships were cubic for the HS group. Only one subject exhibited a positive linear (r2 = 0.681) relationship for the MMGMPF versus isometric torque relationship for either the LS or HS groups. These findings suggested that strength differences do not affect the patterns of responses for MMG amplitude or MPF. The lack of consistency between the individual and composite patterns of responses suggested some degree of inter-individual variability. Therefore, future studies should examine the individual patterns of response to draw conclusions about motor control strategies.

KW - Mechanomyography

KW - Motor unit firing rate

KW - Motor unit recruitment

KW - Muscle strength

KW - Polynomial regression

UR - http://www.scopus.com/inward/record.url?scp=33947522862&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33947522862&partnerID=8YFLogxK

U2 - 10.1016/j.jneumeth.2006.11.007

DO - 10.1016/j.jneumeth.2006.11.007

M3 - Article

C2 - 17187865

AN - SCOPUS:33947522862

VL - 161

SP - 212

EP - 219

JO - Journal of Neuroscience Methods

JF - Journal of Neuroscience Methods

SN - 0165-0270

IS - 2

ER -