Some Central and Peripheral Factors Affecting Human Motoneuronal Output in Neuromuscular Fatigue

@article{Gandevia1992SomeCA,
  title={Some Central and Peripheral Factors Affecting Human Motoneuronal Output in Neuromuscular Fatigue},
  author={S. Gandevia},
  journal={Sports Medicine},
  year={1992},
  volume={13},
  pages={93-98}
}
SummaryFatigue may be defined as a reduction in the maximal force-generating capacity of a muscle. It may result from peripheral processes distal to the neuromuscular junction and from central processes controlling the discharge rate of motoneurons. When assessed with a sensitive test using twitch interpolation, most “maximal” voluntary contractions approach but do not attain optimal muscle output. During fatigue, reflex inputs from intramuscular receptors may contribute to a decline in motor… Expand
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Unlike Voluntary Contractions, Stimulated Contractions of a Hand Muscle Do Not Reduce Voluntary Activation or Motoneuronal Excitability.
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Voluntary activation and motoneuron excitability decreased only when descending voluntary drive was present during the fatiguing task, suggesting that neither sensory feedback from the fatigued muscle nor repetitive activation of motoneurons underlie the changes, whereas they are consistent with mot oneuronal inhibition by released factors linked to voluntary drive. Expand
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TLDR
It is suggested that a superimposed high‐frequency train of stimuli is a more sensitive indicator of central activation failure during isometric MVCs compared with either the superimposed single or double stimuli methods. Expand
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It cannot be generalized that the muscles of old humans are either more or less fatigable than young adults because the extent of the difference in fatigability relies strongly on the fatigue task performed (task‐dependency). Expand
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TLDR
It is concluded that peripheral reflex inhibition of α-motoneurons via small-diameter muscle afferents is of minor significance for the development of the central fatigue that was found to occur during the first voluntary contraction. Expand
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The findings indicate that corticomotor excitability increases during a sustained submaximal voluntary contraction and that, as fatigue develops, there is a progressive buildup of intracortical inhibition. Expand
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TLDR
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TLDR
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Altered reflex sensitivity after repeated and prolonged passive muscle stretching.
TLDR
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