A feasibility study of application and potential effects of a single session transcranial direct current stimulation (tDCS) on competitive anxiety, mood state, salivary levels of cortisol and alpha amylase in elite athletes under a real-world competition

Effect of Transcranial Direct Current Stimulation on Professional Female Soccer Players’ Recovery Following Official Matches

“…The results of the present study of improved WB following combined recovery training and tDCS interventions are generally in line with recent studies demonstrating the efficacy of tDCS on subjective measures in athletes (Angius et al, 2019;Mehrsafar et al, 2020;Moreira et al, 2021), especially in that, like previous studies, we found improvements in WB even from the sham condition. Moreira et al ( 2021) applied a-tDCS using similar parameters to the present study (þF3/ÀF4 montage, 2 mA, 20 min) among a sample of professional male soccer athletes (under age 20 years) following official matches, and they found improvements in WB and cardiac autonomic control with both a-tDCS and sham conditions.…”

“…These authors demonstrated that applying tDCS increased perceptions of vigor, and decreased fatigue, tension, somatic and cognitive anxiety. Moreover, Mehrsafar et al (2020) also reported that tDCS over the DLPFC resulted in lower salivary cortisol and alpha-amylase concentrations, indicating that this tDCS montage may modulate competitive anxiety and physiological stress responses associated with the competition. Indeed, Angius et al, (2019) reported reduced RPE during cycling time-to-exhaustion (TTE), with a significant longer TTE following a-tDCS compared to sham-tDCS in healthy individuals.…”

“…Moreira et al ( 2021) applied a-tDCS using similar parameters to the present study (þF3/ÀF4 montage, 2 mA, 20 min) among a sample of professional male soccer athletes (under age 20 years) following official matches, and they found improvements in WB and cardiac autonomic control with both a-tDCS and sham conditions. Moreover, Mehrsafar et al (2020) assessed the effects of tDCS over the DLPFC (þF3/ÀF4 montage) on mood, competitive anxiety, and neuroendocrine responses among elite archers in 'real-world' competition. These authors demonstrated that applying tDCS increased perceptions of vigor, and decreased fatigue, tension, somatic and cognitive anxiety.…”

“…We included the following criteria: (a) power ¼ 0.8; (b) medium effect size (g2 ¼.07); and (c) a ¼.05, number of groups ¼ 2, number of measurements ¼ 4, and nonsphericity correction ¼ 1. We based the medium effect size assumption on the results of previous studies, using tDCS with similar parameters for improving subjective measures related to exercise similar to the present study (Holgado et al, 2019;Mehrsafar et al, 2020;Valenzuela et al, 2019). This power analysis yielded an estimated required sample size of 12.…”

“…Moreover, studies have found a reduction in RPE associated with increased exercise performance targeting the left dorsolateral prefrontal cortex (DLPFC) (Angius et al, 2019), the M1 (Angius et al, 2016), and the temporal cortex (Okano et al, 2015). In a recent study with elite archers in 'real-world' competition, Mehrsafar et al (2020) demonstrated that applying tDCS with the anode electrode (þ) over the left DLPFC and the cathode (-) over the right DLPFC (þF3/ÀF4 montage) increased vigor and decreased the perceived fatigue, and tension (assessed by the Brunnel Mood Scale) as well as somatic and cognitive anxiety (assessed by the Competitive State Anxiety Inventory 2). However, it should be noted that other studies did not reproduce tDCS induced positive findings on perceived fatigue (i.e., RPE) in non-athletes during vigorous continuous (Okano et al, 2017) or repeated sprint exercise (Alix-Fages et al, 2021).…”