Effects of transcranial direct current stimulation on pre-competitive cognitive performance and anxiety in collegiate athletes: a randomized controlled trial

Sports is a broad field in which success demands a lot of practice and self-discipline. The pressure to perform best and the emotional turmoil of the situation may cause pre-competitive anxiety, hence affecting an athlete's cognitive functions. This study aimed to evaluate the effect of Transcranial Direct Current Stimulation (tDCS) on pre-competitive anxiety and cognitive performance in collegiate athletes. Nineteen (Male:Female; 10:9) collegiate athletes from Haryana, India, aged 18-25 years, were recruited before a National level Inter-University competition in Volleyball discipline. Participants were randomly relocated 1:1 to experimental or control groups. The experimental group received two milliampere tDCS over the dorsolateral prefrontal cortex for 20 min, and the control group received a placebo (sham tDCS with current turned off after 30 s) for ten consecutive days. The outcome measures were Beck Anxiety Inventory (BAI) scales, biofeedback analysis (E.M.G. biofeedback), Digit symbol substitute test (DSST) and Stroop colour and word test (SCWT) measured at baseline and post-treatment. From a total of 19 randomized athletes, 12 completed treatments and within-group analysis revealed a p value of < 0.05 of BAI, DSST, SCWT & E.M.G. biofeedback in the Experimental Group. Post-treatment, between-group analysis revealed significantly lower BAI (p < 0.05) and significantly higher SCWT, DSST and E.M.G. biofeedback (p < 0.05) values in the experimental group. Transcranial direct current stimulation (tDCS) is a safe and advanced neurostimulation method for regulating anxiety and cognition, enhancing sports performance among collegiate athletes. The trial was registered at ctri.nic.in (CTRI/2020/06/025749).