title: Motor cortex excitability is not differentially modulated following skill and strength training.
abstract: OBJECTIVE
  A single session of skill or strength training can modulate the primary motor cortex (M1), which manifests as increased corticospinal excitability (CSE) and decreased short-latency intra-cortical inhibition (SICI). We tested the hypothesis that both skill and strength training can propagate the neural mechanisms mediating cross-transfer and modulate the ipsilateral M1 (iM1).
  
  
  METHODS
  Transcranial magnetic stimulation (TMS) measured baseline CSE and SICI in the contralateral motor cortex (cM1) and iM1. Participants completed 4 sets of unilateral training with their dominant arm, either visuomotor tracking, metronome-paced strength training (MPST), self-paced strength training (SPST) or control. Immediately post training, TMS was repeated in both M1s.
  
  
  RESULTS
  Motor-evoked potentials (MEPs) increased and inhibition was reduced for skill and MPST training from baseline in both M1s. Self-paced strength training and control did not produce changes in CSE and SICI when compared to baseline in both M1s. After training, skill and MPST increased CSE and decreased SICI in cM1 compared to SPST and control. Skill and MPST training decreased SICI in iM1 compared to SPST and control post intervention; however, CSE in iM1 was not different across groups post training.
  
  
  CONCLUSIONS
  Both skill training and MPST facilitated an increase in CSE and released SICI in iM1 and cM1 compared to baseline. Our results suggest that synchronizing to an auditory or a visual cue promotes neural adaptations within the iM1, which is thought to mediate cross transfer.
authors.affiliation: Centre for Physical Activity and Nutrition Research, School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Leung
authors.affiliation: Centre for Physical Activity and Nutrition Research, School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia.
authors.forename: T
authors.initials: T
authors.lastname: Rantalainen
authors.affiliation: Centre for Physical Activity and Nutrition Research, School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia.
authors.forename: W-P
authors.initials: WP
authors.lastname: Teo
authors.affiliation: Department of Rehabilitation, Nutrition and Sport, School of Allied Health, La Trobe University, Melbourne, Australia. Electronic address: D.Kidgell@latrobe.edu.au.
authors.forename: D
authors.initials: D
authors.lastname: Kidgell
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D007537:Isometric Contraction; D007858:Learning / Q000502:physiology*; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D009048:Motor Skills / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D055070:Resistance Training / Q000379:methods*; D018709:Statistics, Nonparametric; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: corticospinal excitability; cross education; cross-transfer; metronome-paced strength; short-latency intra-cortical inhibition; visuomotor skill