Estimulación transcraneal de corriente continua anódica como potencial recurso ergogénico para fuerza muscular y percepción de esfuerzo:: una revisión crítica

In the last decades, several studies have been investigating the ideal dose-response as to the frequency, intensity and volume of training to achieve the increase of muscular strength, in both athletes and non-athletes. Dose-response is essential for the prescription of training, since its mismanagement may lead to a high risk of developing repetitive strain injuries, as well as to the failure to develop the expected strength. In subjects with advanced level of strength training, it is extremely important to increase their intensity and training volume. In this sense, with the advances found in the area of ​​strength training and the need for new strategies to optimize force gains, a new method has been gaining strength in the literature, the transcranial direct current stimulation (tDCS). Therefore, the objective of the present study is to critically analyze the effects of tDCS as a potential ergogenic resource for the performance of muscular strength and perceived exertion. Thus, a search was performed on the Pubmed/Medline, ISI Web of Knowledge and Scielo databases in the English language and with the key words: muscular strength, muscular endurance, transcranial direct current stimulation, tDCS. We compared the effect of anodic tDCS (a-tDCS) to a sham/control condition on muscle strength results. No study mentions the negative side effects of the intervention. The data show differences between studies investigating muscle strength and endurance assessment studies with regard to the successful use of tDCS. Studies investigating the efficiency of tDCS in improving muscle strength demonstrate positive effects of a-tDCS in 66.7% of the parameters tested. Most data consistently show a-tDCS influence on muscle strength, but not on resistance performance.