PMID- 32305018
OWN - NLM
STAT- MEDLINE
DCOM- 20200904
LR  - 20200904
IS  - 1873-5711 (Electronic)
IS  - 1050-6411 (Linking)
VI  - 52
DP  - 2020 Jun
TI  - The reliability of surface EMG derived motor unit variables.
PG  - 102419
LID - S1050-6411(20)30034-1 [pii]
LID - 10.1016/j.jelekin.2020.102419 [doi]
AB  - Motor unit (MU) recordings obtained from surface electromyography (sEMG) 
      decomposition are used to investigate the neural control of muscle in response to 
      interventions, but our understanding of the longer-term reliability of MU 
      variables is limited. This study examined the reliability of MU variables in the 
      flexor carpi radialis (FCR) and tibialis anterior (TA) over a three-month period. 
      Forty college-aged participants completed isometric wrist flexion (n = 20) and 
      dorsiflexion (n = 20). There were 3 maximal isometric voluntary contractions 
      (MVC) and 3 ramp contractions to 60% of MVC on four separate sessions separated 
      by a total of 13 weeks. Intraclass correlation coefficients (ICC) were calculated 
      from a fully nested ANOVA model. Maximal force was highly reliable 
      (ICC = 0.94-0.99). The ICC values ranged from 0.49 to 0.92 for the FCR MU 
      variables and from 0.58 to 0.96 for the TA MU variables. All MU variables 
      exhibited a high degree of stability of means across test session and consistency 
      within subjects, with the exception of the number of MUs detected in the TA. Poor 
      ICC values did not reflect poor reliability but rather, convergence towards a 
      narrow range of physiologically normal values. Surface EMG decomposition of a 
      large population of MUs showed no differences in common drive between FCR (0.273) 
      and for the TA (0.267) across test sessions. Forty percent of the sampled MUs in 
      both muscles had a common drive of 0.30 or greater, which provides indirect 
      support for the validity of the decompositions. MU variables may be used to 
      monitor adaptations to a longer-term intervention study.
CI  - Copyright (c) 2020 Elsevier Ltd. All rights reserved.
FAU - Hoshizaki, Thomas
AU  - Hoshizaki T
AD  - Brock University, St. Catharines, ON, Canada.
FAU - Clancy, Edward A
AU  - Clancy EA
AD  - Worcester Polytechnic Institute, Worcester, MA, USA.
FAU - Gabriel, David A
AU  - Gabriel DA
AD  - Brock University, St. Catharines, ON, Canada.
FAU - Green, Lara A
AU  - Green LA
AD  - Brock University, St. Catharines, ON, Canada; Wilfrid Laurier University, 
      Waterloo, ON, Canada. Electronic address: lgreen@wlu.ca.
LA  - eng
PT  - Evaluation Study
PT  - Journal Article
DEP - 20200411
PL  - England
TA  - J Electromyogr Kinesiol
JT  - Journal of electromyography and kinesiology : official journal of the 
      International Society of Electrophysiological Kinesiology
JID - 9109125
SB  - IM
MH  - Adult
MH  - Electromyography/methods/*standards
MH  - Female
MH  - Humans
MH  - *Isometric Contraction
MH  - Male
MH  - Motor Neurons/*physiology
MH  - Muscle, Skeletal/innervation/*physiology
MH  - Reproducibility of Results
MH  - Wrist/physiology
OTO - NOTNLM
OT  - Intraclass correlation coefficient
OT  - Motor unit
OT  - Motor unit discharge rates
OT  - Reliability
OT  - Surface electromyography
COIS- Declaration of Competing Interest The authors declared that there is no conflict 
      of interest.
EDAT- 2020/04/19 06:00
MHDA- 2020/09/05 06:00
CRDT- 2020/04/19 06:00
PHST- 2019/04/27 00:00 [received]
PHST- 2020/03/28 00:00 [revised]
PHST- 2020/04/01 00:00 [accepted]
PHST- 2020/04/19 06:00 [pubmed]
PHST- 2020/09/05 06:00 [medline]
PHST- 2020/04/19 06:00 [entrez]
AID - S1050-6411(20)30034-1 [pii]
AID - 10.1016/j.jelekin.2020.102419 [doi]
PST - ppublish
SO  - J Electromyogr Kinesiol. 2020 Jun;52:102419. doi: 10.1016/j.jelekin.2020.102419. 
      Epub 2020 Apr 11.