Reflex origin for the slowing of motoneurone firing rates in fatigue of human voluntary contractions.
During fatigue from a sustained maximal voluntary contraction (m.v.c.) the mean motoneurone discharge rates decline. In the present experiments we found no recovery of firing rates after 3 min of rest if the fatigued muscle was kept ischaemic, but near full recovery 3 min after the blood supply was restored. Since 3 min is thus sufficient time for recovery of any central changes in excitability, the results support the hypothesis that, during fatigue, motoneurone firing rates may be regulated by a peripheral reflex originating in response to fatigue-induced changes within the muscle.
D001696:Biomechanical Phenomena; D006801:Humans; D007511:Ischemia / Q000503:physiopathology; D009046:Motor Neurons / Q000502:physiology*; D009119:Muscle Contraction; D009132:Muscles / Q000098:blood supply / Q000502:physiology*; D013997:Time Factors