title: Estimating electromyographic and heart rate fatigue thresholds from a single treadmill test.
abstract: BACKGROUND
  The purposes of this study were to (1) develop a fatigue threshold based on electromyography (EMG) and heart rate (HR) responses for treadmill running from a single incremental test; and (2) propose a new fatigue threshold called the RV(EMGFT) and RV(HRFT).
  
  
  METHODS
  Eleven men performed incremental treadmill exercise to exhaustion on a single occasion. The RV(EMGFT) and RV(HRFT) were defined as the average of the highest velocity that resulted in a nonsignificant slope coefficient for the EMG amplitude versus time relationship and the lowest velocity that resulted in a significant positive slope coefficient.
  
  
  RESULTS
  There was a significant (P < 0.05) difference between the 2 thresholds [RV(EMGFT) = 11.7 ± 0.6 km/h and RV(HRFT) = 8.3 ± 0.8 km/h].
  
  
  CONCLUSIONS
  The fatigue threshold for EMG amplitude and heart rate can be determined from a single incremental treadmill test, but there are differences between cardiac and neuromuscular factors of fatigue.
authors.affiliation: Wayne State University, Eugene Applebaum College of Pharmacy & Health Sciences, 259 Mack Avenue, Room 2248, Detroit, Michigan 48201, USA.
authors.forename: Darren R
authors.initials: DR
authors.lastname: Guffey
authors.forename: Bruno J
authors.initials: BJ
authors.lastname: Gervasi
authors.forename: Alex A
authors.initials: AA
authors.lastname: Maes
authors.forename: Moh H
authors.initials: MH
authors.lastname: Malek
mesh_terms: D000328:Adult; D004576:Electromyography / Q000379:methods / Q000592:standards; D015444:Exercise / Q000502:physiology; D005080:Exercise Test / Q000379:methods* / Q000592:standards; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D012420:Running / Q000502:physiology*; D055815:Young Adult