title: The role of central and peripheral muscle fatigue in postcancer fatigue: a randomized controlled trial.
abstract: BACKGROUND
  Postcancer fatigue is a frequently occurring problem, impairing quality of life. Little is known about (neuro)physiological factors determining postcancer fatigue. It may be hypothesized that postcancer fatigue is characterized by low peripheral muscle fatigue and high central muscle fatigue.
  
  
  OBJECTIVE
  The aims of this study were to examine whether central and peripheral muscle fatigue differ between fatigued and non-fatigued cancer survivors and to examine the effect of cognitive behavioral therapy (CBT) on peripheral and central muscle fatigue of fatigued cancer survivors in a randomized controlled trial.
  
  
  METHODS
  Sixteen fatigued patients in the intervention group (CBT) and eight fatigued patients in the waiting list group were successfully assessed at baseline and six months later. Baseline measurements of 20 fatigued patients were compared with 20 non-fatigued patients. A twitch interpolation technique and surface electromyography were applied, respectively, during sustained contraction of the biceps brachii muscle.
  
  
  RESULTS
  Muscle fiber conduction velocity (MFCV) and central activation failure (CAF) were not significantly different between fatigued and non-fatigued patients. Change scores of MFCV and CAF were not significantly different between patients in the CBT and waiting list groups. Patients in the CBT group reported a significantly larger decrease in fatigue scores than patients in the waiting list group.
  
  
  CONCLUSIONS
  Postcancer fatigue is neither characterized by abnormally high central muscle fatigue nor by low peripheral muscle fatigue. These findings suggest a difference in the underlying physiological mechanism of postcancer fatigue vs. other fatigue syndromes.
authors.affiliation: Department of Medical Oncology, Radboud University Medical Centre, Nijmegen, The Netherlands. Electronic address: Hetty.Prinsen@radboudumc.nl.
authors.forename: Hetty
authors.initials: H
authors.lastname: Prinsen
authors.affiliation: Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands; Epilepsy Centre Kempenhaeghe, Heeze, The Netherlands.
authors.forename: Johannes P
authors.initials: JP
authors.lastname: van Dijk
authors.affiliation: Epilepsy Centre Kempenhaeghe, Heeze, The Netherlands.
authors.forename: Machiel J
authors.initials: MJ
authors.lastname: Zwarts
authors.affiliation: Department of Radiation Oncology, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Jan Willem H
authors.initials: JW
authors.lastname: Leer
authors.affiliation: Expert Centre for Chronic Fatigue, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Gijs
authors.initials: G
authors.lastname: Bleijenberg
authors.affiliation: Department of Medical Oncology, Radboud University Medical Centre, Nijmegen, The Netherlands; Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Hanneke W M
authors.initials: HW
authors.lastname: van Laarhoven
mesh_terms: D015928:Cognitive Behavioral Therapy; D004576:Electromyography; D015444:Exercise / Q000502:physiology; D005221:Fatigue / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D018763:Muscle Fatigue / Q000502:physiology*; D018482:Muscle, Skeletal / Q000503:physiopathology; D009369:Neoplasms / Q000150:complications* / Q000503:physiopathology; D012146:Rest; D017741:Survivors; D016896:Treatment Outcome; D014850:Waiting Lists
keywords: Postcancer fatigue; central activation failure; central muscle fatigue; cognitive behavioral therapy; muscle fiber conduction velocity; peripheral muscle fatigue; surface electromyography; twitch interpolation technique