Corticospinal Excitability to the Biceps Brachii Is not Different when Arm Cycling at a Self-Selected or Fixed Cadence

Abstract

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 seconds for one minute. The average cadence of the SSC cycling trial was then used as a target for FC of cycling that the participants were instructed to maintain. 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) were not different between groups. Conclusions: Focusing on maintaining a FC cadence during arm cycling does not influence corticospinal excitability as assessed via TMS-evoked MEPs.