The impact of bilateral anodal transcranial direct current stimulation of the premotor and cerebellar cortices on physiological and performance parameters of gymnastic athletes: a randomized, cross-over, sham-controlled study

Abstract

Professional sports performance relies critically on the interaction between the brain and muscles during movement. Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique which modulates cortical excitability and can be used to improve motor performance in athletes. The present study aimed to investigate the effect of bilateral anodal tDCS (2 mA, 20 min) over the premotor cortex or cerebellum on motor and physiological functions and peak performance of professional gymnastics athletes. Seventeen professional gymnastics athletes participated in a randomized, sham-controlled, crossover study. In this study, we assessed the efficacy of two anodal tDCS protocols (2 mA, 20 min) with stimulation over the bilateral premotor cortex or cerebellum with the return electrodes placed over the opposite supraorbital areas. Power speed, strength coordination, endurance, static and dynamic strength, static and dynamic flexibility, and rating of perceived exertion were measured before and immediately after tDCS interventions (bilateral anodal tDCS over premotor cortices, anodal tDCS over the cerebellum, and sham tDCS). Additionally, physiological muscle performance parameters, including maximum voluntary isometric contraction (MVIC) of upper body muscles, were assessed during tDCS. Bilateral anodal tDCS over the premotor cortex, compared to anodal tDCS over the cerebellum and sham tDCS conditions, significantly improved power speed, strength coordination, and static and dynamic strength variables of professional gymnastics athletes. Furthermore, bilateral anodal tDCS over the cerebellum, compared to sham tDCS, significantly improved strength coordination. Moreover, bilateral premotor anodal tDCS significantly increased MVIC of all upper body muscles during stimulation, while anodal tDCS over the cerebellum increased MVIC in only some muscles. Bilateral anodal tDCS over the premotor cortex, and to a minor degree over the cerebellum, might be suited to improve some aspects of motor and physiological functions and peak performance levels of professional gymnastics athletes.Clinical Trial Registration ID: IRCT20180724040579N2.

Cerebellar Transcranial Direct Current Stimulation Applied over Multiple Days Does Not Enhance Motor Learning of a Complex Overhand Throwing Task in Young Adults

“…The findings of the current study are not consistent with the findings of the majority of the initial previous single-session c-tDCS studies by other research groups [6][7][8][9][10], although most of these studies used adaptation-learning paradigms. Furthermore, the findings differ from a very recent study that reported that c-tDCS improved strength and coordination in full-body motor tasks in gymnasts [55]. However, this study used a novel bilateral electrode montage.…”

“…Nonetheless, it is possible that another set of c-tDCS parameters could be more effective. For example, a recent study used bilateral anodal c-tDCS and demonstrated improvements in complex whole-body tasks in gymnasts [55]. Another study found that a bilateral electrode montage (anode over the right cerebellar hemisphere, cathode over the left cerebellar hemisphere) and a 4 mA current strength outperformed several other unilateral montage and lowercurrent-strength combinations.…”

Does a single session of transcranial direct current stimulation enhance both physical and psychological performance in national- or international-level athletes? A systematic review

“…With the exception of eight studies applying a cephalic montage of the return electrode, all examined studies applied an extracephalic montage of the return electrode. Regarding the tDCS application protocol, all studies opted for the offline modality (testing after stimulation), with five studies including also the online stimulation modality (testing during stimulation) ( Hazime et al, 2017 ; Vargas et al, 2018 ; Fortes et al, 2022 ; Moreira et al, 2022 ; Anoushiravani et al, 2023 ). Three studies out of 18 studies did not measure side effects of the tDCS intervention.…”

The impact of cerebellar transcranial direct current stimulation on isometric bench press performance in trained athletes

“…Critically, the authors used a multi-modal stimulation protocol, where activity of the dorsolateral prefrontal cortex (dlPFC) was additionally suppressed. In another study, trained gymnasts were investigated to evaluate the effects of bilateral anodal CB-tDCS on static and dynamic strength performance [ 61 ]. Again, no performance improvements were observed for static and dynamic strength in the study.…”