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Updated: Jan 29, 2026

Corticospinal Excitability Modulation During Action Observation
Published on: December 31, 2013
Corticospinal Excitability to the Biceps Brachii is Not Different When Arm Cycling at a Self-Selected or Fixed
Evan J Lockyer1, Anna P Nippard2, Kaitlyn Kean3
1Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL A1C5S7, Canada. ejl006@mun.ca.
Background:
The present study compared corticospinal excitability to the biceps brachii muscle during arm cycling at a self-selected and a fixed cadence (SSC and FC, respectively). We hypothesized that corticospinal excitability would not be different between the two conditions.
Methods:
The SSC was initially performed and the cycling cadence was recorded every 5 s for one minute. The average cadence of the SSC cycling trial was then used as a target for the FC of cycling that the participants were instructed to maintain. The motor evoked potentials (MEPs) elicited via transcranial magnetic stimulation (TMS) of the motor cortex were recorded from the biceps brachii during each trial of SSC and FC arm cycling.
Results:
Corticospinal excitability, as assessed via normalized MEP amplitudes (MEPs were made relative to a maximal compound muscle action potential), was not different between groups.
Conclusions:
Focusing on maintaining a fixed cadence during arm cycling does not influence corticospinal excitability, as assessed via TMS-evoked MEPs.
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