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Updated: May 21, 2026
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Non-invasive Assessment of Changes in Corticomotoneuronal Transmission in Humans
Published on: May 24, 2017
Motor cortex excitability does not increase during sustained cycling exercise to volitional exhaustion
Simranjit K Sidhu1, Andrew G Cresswell, Timothy J Carroll
1School of Human Movement Studies, The University of Queensland, Brisbane, Queensland, Australia. simranjit.sidhu@uqconnect.edu.au
Journal of Applied Physiology (Bethesda, Md. : 1985)
|June 9, 2012
Summary
Sustained cycling exercise does not alter motor cortex excitability, unlike single-joint contractions. This suggests different physiological responses influence corticospinal changes during various exercise types.
Area of Science:
- Exercise Physiology
- Neuroscience
- Motor Control
Background:
- Motor cortex excitability increases with fatigue during sustained single-joint contractions.
- The effects of sustained locomotor exercise on corticospinal excitability are not well understood.
Purpose of the Study:
- To investigate changes in spinal and cortical excitability during sustained cycling exercise.
- To compare corticospinal responses to sustained cycling versus single-joint contractions.
Main Methods:
- Nine subjects performed sustained cycling at 75% and 105% of maximum workload (Wmax).
- Motor evoked potentials (MEPs) and cervicomedullary evoked potentials (CMEPs) were recorded during exercise.
- Responses were compared to non-fatiguing control cycling bouts.
Main Results:
- No significant changes in MEPs or CMEPs were observed during sustained cycling.
- Corticospinal excitability remained stable throughout the cycling protocol.
Conclusions:
- Sustained cycling exercise does not increase motor cortical excitability.
- Contrasting corticospinal responses between cycling and single-joint contractions may stem from differing systemic physiological consequences.
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