title: Intersession reliability of the electromyographic signal during incremental cycle ergometry: quadriceps femoris.
abstract: BACKGROUND
  The purposes of this investigation were to determine the: (1) reproducibility of the patterns of responses for electromyographic (EMG) amplitude and mean power frequency (MPF); and (2) intraclass correlation coefficient (ICC) of the EMG amplitude and MPF during three incremental cycle ergometer tests separated by 48 hours.
  
  
  METHODS
  Ten men performed incremental cycle ergometry tests to exhaustion on three separate occasions. Surface EMG signals were recorded simultaneously from the three superficial quadriceps muscles at each trial.
  
  
  RESULTS
  Polynomial regression indicated that, for >95% of the cases, the best-fit model was the same at each trial for EMG amplitude but not for EMG MPF. The ICC values were high for EMG amplitude but low for EMG MPF.
  
  
  CONCLUSIONS
  These results indicate that EMG amplitude is a reliable measure of motor unit activation strategy during incremental cycle ergometry, whereas the EMG MPF was unreliable.
authors.affiliation: Integrative Physiology of Exercise Laboratory, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201, USA.
authors.forename: Liesle A
authors.initials: LA
authors.lastname: Travis
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Arthmire
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Baig
authors.forename: Allon
authors.initials: A
authors.lastname: Goldberg
authors.forename: Moh H
authors.initials: MH
authors.lastname: Malek
mesh_terms: D000328:Adult; D004576:Electromyography / Q000592:standards*; D016552:Ergometry / Q000592:standards*; D005080:Exercise Test / Q000592:standards; D006801:Humans; D008297:Male; D052097:Quadriceps Muscle / Q000502:physiology*; D015203:Reproducibility of Results