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Position sense at the elbow after fatiguing contractions
1School of Physiotherapy, University of South Australia, Adelaide.
Experimental Brain Research
|January 1, 1993
Summary
Muscle fatigue can impair limb position sense. This study found that fatigue-induced changes in proprioception are not solely responsible for reduced arm position matching accuracy, suggesting central factors are involved.
Area of Science:
- Neuroscience
- Human Physiology
- Motor Control
Background:
- Muscle fatigue is commonly linked to decreased motor control and increased clumsiness.
- Altered proprioceptive feedback from muscle receptors is a potential mechanism underlying fatigue-related motor impairments.
Purpose of the Study:
- To investigate the impact of muscle fatigue on the ability to match contralateral arm positions.
- To determine if changes in proprioceptive signals during fatigue contribute to impaired limb position sense.
Main Methods:
- Thirteen participants performed elbow angle matching tasks before and after inducing fatigue in one arm.
- Contractile fatigue was achieved through a series of maximal voluntary contractions of elbow flexor muscles.
Main Results:
- Fatigue in either the target or matching arm generally altered individual arm position matching abilities.
- No consistent reciprocal changes were observed when the fatigued arm served as the matching arm versus the non-fatigued arm.
- Significant inter-subject variability in fatigue effects on proprioception was noted.
Conclusions:
- Fatigue-related deficits in arm position matching are not exclusively explained by peripheral proprioceptive alterations.
- Central fatigue mechanisms likely play a significant role in the observed changes in limb position sense during muscle fatigue.
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