Acute effects of transcranial direct current stimulation on cycling and running performance. A systematic review and meta-analysis.

Transcranial direct current stimulation (tDCS) has been proven to induce positive effects on athletic performance. The present study aimed to analyse the effect of anodal-tDCS on endurance (time to exhaustion [TTE] or endurance time trial [ETT]) and sprint performance during cycling and running tasks. We performed a systematic literature review in the databases Medline (via PubMed), SPORTDiscus and Science Direct. We included only randomised controlled trials conducted with healthy individuals in which an anodal-tDCS protocol was applied prior to cycling or running tests. The effect of anodal-tDCS (experimental condition) was compared against sham stimulation (control condition). A total of 15 interventions from 13 studies were included. The sub-group analysis revealed a positive effect of anodal-tDCS on TTE (standardised mean differences [SMD] = 0.37; 90% confidence interval [CI] = 0.13, 0.61;