Corticomotor excitability and perception of effort during sustained exercise in the chronic fatigue syndrome. Academic Article uri icon

Overview

abstract

  • OBJECTIVE: We have investigated the possibility of a central basis for the complaints of fatigue and poor exercise tolerance in subjects with chronic fatigue syndrome (CFS). METHODS: Transcranial magnetic stimulation of the motor cortex was used to measure sequential changes in motor evoked potential (MEP) amplitude, post-excitatory silent period (SP) duration and twitch force of the biceps brachii muscle during a 20% maximum isometric elbow flexor contraction maintained to the point of exhaustion. Ten patients with post-infectious CFS and 10 age- and sex-matched control subjects were studied. Results were analysed using non-parametric repeated measures analysis of variance (Friedman's test) and Mann-Whitney U-tests for intra- and inter-group comparisons respectively. RESULTS: Mean endurance time for the CFS group was lower (13.1+/-3.2 min, mean +/- SEM) than controls (18.6+/-2.6 min, P < 0.05) and CFS subjects reported higher ratings of perceived exertion. During the exercise period MEP amplitude and SP duration increased in both groups but to a lesser extent in CFS subjects. Interpolated twitch force amplitude also increased during exercise, being more pronounced in CFS subjects. CONCLUSION: The findings are in keeping with an exercise-related diminution in central motor drive in association with an increased perception of effort in CFS.

publication date

  • November 1, 1999

Research

keywords

  • Energy Metabolism
  • Fatigue Syndrome, Chronic
  • Motor Cortex
  • Perception

Identity

Scopus Document Identifier

  • 0032829682

Digital Object Identifier (DOI)

  • 10.1016/s1388-2457(99)00144-3

PubMed ID

  • 10576483

Additional Document Info

volume

  • 110

issue

  • 11