Determining contribution of central and peripheral fatigue after modified Bruce protocol in young healthy men using TMS and M-wave methods

Fatigue is as a reversible decrease in performance during exercise, which more understanding about its causes and cure is one of the most important approaches of exercise researches. Thus, defining the type of fatigue in different activities can increase our knowledge and also help for future studies in this field. Thus, the aim of this study was to define the contribution of central and peripheral fatigue in Bruce incremental exhausting protocol. For this purpose, 16 young healthy subjects were selected and performed modified Bruce protocol until volitional exhaustion. Transcranial magnetic stimulation (TMS), M-wave, maximal voluntary contraction (MVC) of the tibialis anterior muscle and rate of perceived exertion (RPE) were assessed prior and immediately after exercise. The results showed significant decrease in MVC (12.5%) and TMS amplitude (10.2%), but not in M-wave amplitude (1.75%), immediately after exercise (P