Transcranial Direct Current Stimulation Does Not Improve Countermovement Jump Performance in Young Healthy Men.

ABSTRACT: Romero-Arenas, S, Calderón-Nadal, G, Alix-Fages, C, Jerez-Martínez, A, Colomer-Poveda, D, and Márquez, G. Transcranial direct current stimulation does not improve countermovement jump performance in young healthy men. J Strength Cond Res 35(10): 2918-2921, 2021-The main purpose of this study was to report the effects of transcranial direct current stimulation (tDCS) on countermovement jump (CMJ) performance in young healthy men. Seventeen healthy male subjects volunteered for the study (age: 22.4 ± 2.6 years; body mass: 71.8 ± 8.7 kg; height: 174.6 ± 5.9 cm; and CMJ height: 36.8 ± 6.3 cm). After a familiarization session, subjects underwent 3 experimental conditions, 7 days apart, in a randomized, double-blinded crossover design: anodal, cathodal, and sham tDCS. The stimulation was applied over the dorsolateral prefrontal cortex for 15 minutes. During experimental sessions, subjects completed a warm-up and 3 CMJ trials separated by 1 minute before and after each of the 3 experimental conditions. Countermovement jump height and muscular peak power were extracted from the best CMJ in each moment. A 2-way repeated-measures analysis of variance with time and condition as factors were performed for CMJ height and muscular peak power. Effect size analysis was conducted using Cohen's d coefficient. The analysis did not show either significant main effects or interactions for both time and condition factors in the CMJ performance (p > 0.05). Furthermore, effect size was trivial for all conditions (d: 0.01-0.14) in CMJ height and muscular peak power. These findings suggest that tDCS may not be a valuable tool to improve vertical jump performance.

Anodal transcranial direct current stimulation enhances strength training volume but not the force-velocity profile.

PURPOSE: This study aimed to explore the acute effect of transcranial direct current stimulation (tDCS) on the force-velocity relationship, strength training volume, movement velocity, and ratings of perceived exertion. METHODS: Fourteen healthy men (age 22.8 ± 3.0 years) were randomly stimulated over the dorsolateral prefrontal cortex with either ANODAL, CATHODAL or SHAM tDCS for 15 min at 2 mA. The one-repetition maximum (1RM) and force-velocity relationship parameters were evaluated during the bench press exercise before and after receiving the tDCS. Subsequently, participants completed a resistance training session consisting of sets of five repetitions with 1 min of inter-set rest against the 75%1RM until failure. RESULTS: No significant changes were observed in the 1RM or in the force-velocity relationship parameters (p ≥ 0.377). The number of repetitions was higher for the ANODAL compared to the CATHODAL (p = 0.025; ES = 0.37) and SHAM (p = 0.009; ES = 0.47) conditions. The reductions of movement velocity across sets were lower for the ANODAL than for the CATHODAL and SHAM condition (p = 0.014). RPE values were lower for the ANODAL compared to the CATHODAL (p = 0.119; ES = 0.33) and SHAM (p = 0.150; ES = 0.44) conditions. No significant differences between the CATHODAL and SHAM conditions were observed for any variable. CONCLUSION: The application of ANODAL tDCS before a resistance training session increased training volume, enabled the maintenance of higher movement velocities, and reduced RPE values. These results suggest that tDCS could be an effective method to enhance resistance-training performance.

Transcranial direct current stimulation and repeated sprint ability: No effect on sprint performance or ratings of perceived exertion.

The role of transcranial direct current stimulation (tDCS) as an ergogenic aid is receiving attention from scientists to optimize sport performance. Most studies have examined the effects of tDCS on endurance performance during continuous tasks, while the effect of tDCS on high-intensity intermittent tasks has been less investigated. Therefore, this study aimed to explore the acute effects of tDCS on sprint performance and ratings of perceived exertion (RPE) during a repeated sprint ability (RSA) task. Twenty-five healthy males (age: 22.0 ± 2.5 years) participated in a randomized crossover study consisting of three experimental sessions (anodal, cathodal or sham tDCS) separated by 1 week. Each session consisted of (I) tDCS protocol (15 min at 2 mA applied over the dorsolateral prefrontal cortex [DLPFC]), (II) warm-up and (III) RSA task (ten 30-m running sprints separated by 30 s). Total time and RPE values were recorded for each sprint. The two-way ANOVA applied on sprint time did not reveal a significant main effect of tDCS condition (p = .200) neither a significant tDCS condition × number of sprint interaction (p = .716). Similarly, no significant differences were observed for the fatigue index (p = .449), RSAmean (p = .200) or RPE after each sprint (p range = .116-.890). The magnitude of the differences between the tDCS conditions ranged from negligible to small (effect sizes ≤ 0.33). These results suggest that the application of tDCS over the DLPFC is not effective to increase sprint performance or reduce RPE during a RSA task.HIGHLIGHTSTranscranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that could modulate neuromuscular performance.This study aimed to explore the short-term effects of tDCS on sprint performance and ratings of perceived exertion (RPE) during a repeated sprint ability (RSA) task.The application of either ANODAL or CATHODAL tDCS over the DLPFC for 15 minutes did not affect the sprint time of single repeated sprints or the overall metrics of RSA performance (RSAmean and fatigue index).The application of either ANODAL or CATHODAL tDCS over the DLPFC for 15 minutes did not affect the ratings of perceived exertion measured during the repeated sprints task.