{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:29:33Z","timestamp":1785403773359,"version":"3.56.0"},"reference-count":25,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T00:00:00Z","timestamp":1778544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery","award":["20231242"],"award-info":[{"award-number":["20231242"]}]},{"award":["20231242"],"award-info":[{"award-number":["20231242"]}],"id":[{"id":"https:\/\/ror.org\/01h531d29","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Purpose: This study investigated whether an acute bout of submaximal unilateral arm cycling elicits sustained changes in corticospinal excitability (CSE) and short-interval intracortical inhibition (SICI) in the homologous muscles of the non-exercised, resting limb. A secondary aim was to determine whether prior exercise induces a preconditioning effect on subsequent motor output. Methods: Transcranial magnetic stimulation was used to assess motor evoked potential (MEP) amplitude (single-pulse) and SICI (paired-pulse) in the resting non-dominant flexor carpi radialis (FCR) and extensor carpi radialis (ECR) muscles of healthy participants. Measures were obtained at rest, during a 10 min bout of unilateral arm cycling (30 W, 60 rpm), and throughout a 20 min recovery period. To assess potential preconditioning effects, measurements were repeated during a second 2 min cycling bout following a 20 min recovery. Rest and exercise conditions were analyzed separately due to differences in stimulation intensity (RMT vs. AMT). Results: Unilateral arm cycling did not produce sustained changes in CSE or SICI in the resting limb when both arms were at rest. Furthermore, unilateral arm cycling followed by a 20 min recovery period did not result in a preconditioning effect, as CSE in the resting limb was not enhanced during a subsequent unilateral arm cycling bout. Conclusions: Submaximal unilateral arm cycling induces a transient, state-dependent increase in CSE to the non-exercised limb without altering SICI. The absence of SICI modulation suggests that this facilitation is not mediated by GABAA-dependent intracortical mechanisms, and may instead reflect modulation arising from spinal and interlimb locomotor circuitry. The lack of sustained post-exercise effects indicates that low-intensity arm cycling does not induce a plasticity-permissive cortical state, highlighting a distinction between transient, movement-dependent facilitation and longer-lasting exercise-induced neuroplasticity.<\/jats:p>","DOI":"10.3390\/brainsci16050514","type":"journal-article","created":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T13:11:31Z","timestamp":1779196291000},"page":"514","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Submaximal Unilateral Arm Cycling Produces Transient but Not Sustained Changes in Corticospinal Excitability in the Homologous Muscles of the Non-Exercised Limb"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0202-7384","authenticated-orcid":false,"given":"Hiwa","family":"Rahmani","sequence":"first","affiliation":[{"name":"Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, 230 Elizabeth Avenue, St. John\u2019s, NL A1C 5S7, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-5066-4830","authenticated-orcid":false,"given":"Hamid","family":"Amoozi","sequence":"additional","affiliation":[{"name":"Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, 230 Elizabeth Avenue, St. John\u2019s, NL A1C 5S7, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-8618-3676","authenticated-orcid":false,"given":"Ibrahim Saif Allah Ahmed","family":"Refai","sequence":"additional","affiliation":[{"name":"Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, 230 Elizabeth Avenue, St. John\u2019s, NL A1C 5S7, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin E.","family":"Power","sequence":"additional","affiliation":[{"name":"Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, 230 Elizabeth Avenue, St. John\u2019s, NL A1C 5S7, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1152\/jn.00027.2021","article-title":"Moving Forward: Methodological Considerations for Assessing Corticospinal Excitability during Rhythmic Motor Output in Humans","volume":"126","author":"Lockyer","year":"2021","journal-title":"J. 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