Corticospinal responses following strength training: a systematic review and meta-analysis

Dawson J. Kidgell, Daniel R. Bonanno, Ashlyn K. Frazer, Glyn Howatson, Alan J. Pearce

Research output: Contribution to journalReview ArticleResearchpeer-review

24 Citations (Scopus)

Abstract

Strength training results in changes in skeletal muscle; however, changes in the central nervous system also occur. Over the last 15 years, non-invasive brain stimulation techniques, such as transcranial magnetic stimulation, have been used to study the neural adaptations to strength training. This review explored the hypothesis that the neural adaptations to strength training may be due to changes in corticospinal excitability and inhibition and, such changes, contribute to the gain in strength following strength training. A systematic review, according to PRISMA guidelines, identified studies by database searching, hand-searching and citation tracking between January 1990 and the first week of February 2017. Methodological quality of included studies was determined using the Downs and Black quality index. Data were synthesised and interpreted from meta-analysis. Nineteen studies investigating the corticospinal responses following strength training were included. Meta-analysis found that strength training increased strength [standardised mean difference (SMD) 0.84, 95% CI 0.55 to 1.13], decreased short-interval intracortical inhibition (SMD −1.00, 95% CI −1.84 to −0.17) and decreased the cortical silent period (SMD −0.66, 95% CI −1.00 to −0.32). Strength training had no effect on motor threshold (SMD −0.12, 95% CI −0.49 to 0.25), but a borderline effect for increased corticospinal excitability (SMD 0.27, 95% CI 0.00 to 0.54). In untrained healthy participants, the corticospinal response to strength training is characterised by reduced intracortical inhibition and cortical silent period duration, rather than changes in corticospinal excitability. These data demonstrate that strength training targets intracortical inhibitory networks within the primary motor cortex (M1) and corticospinal pathway, characterising an important neural adaptation to strength training.

Original languageEnglish
Pages (from-to)2648-2661
Number of pages14
JournalEuropean Journal of Neuroscience
Volume46
Issue number11
DOIs
Publication statusPublished - 1 Dec 2017

Keywords

  • excitability
  • inhibition
  • intracortical inhibition
  • resistance exercise
  • transcranial magnetic stimulation

Cite this