Research paperEffects of transcranial direct current stimulation on time limit and ratings of perceived exertion in physically active women

- tDCS is a non-invasive brain stimulation technique used to stimulate the cerebral cortex.
- Anodal-tDCS does not improve ratings of perceived exertion in physically active woman.
- Anodal-tDCS improves time to exhaustion in physically active woman.

The limiting factors of maximum performance in humans have been extensively investigated. The aim of this study was to verify the acute effects of transcranial direct current stimulation on time limit (i.e., the time by which an individual is able to sustain a certain intensity of effort) at 100% of peak power (tlim@100%PP) and ratings of perceived exertion (RPE). Eleven moderately active women underwent an anthropometric evaluation and a maximal incremental test in the cycle ergometer, in order to obtain peak power (PP). At the two subsequent visits, which were separated by 48-72 h, participants were randomly assigned to two experimental conditions: anodal stimulation (a-tDCS) and sham. In the a-tDCS condition, the stimulus was applied in the left dorsolateral prefrontal cortex (DLPFC), with intensity of 2 mA for 20 min. In the sham condition, the equipment was switched off after 30 s of stimulation. Immediately after the conditions, participants performed the tlim@100%PP. Immediately after the tlim@100%PP test, the RPE scale was applied. The results demonstrated that the tlim@100%PP was higher in a-tDCS condition compared to sham condition (p = 0.005). No difference was found between the conditions (a-tDCS vs sham) for the RPE (p = 0.52). The anodal stimulus increased the tolerance to the exercise performed in the cycloergometer with maximum load, having some ergogenic effect in exercises of cyclic characteristics.