Zapping the brain to enhance sport performance? An umbrella review of the effect of transcranial direct current stimulation on physical performance.

Concepts such as "neurodoping" have contributed to an expansion in the area of transcranial direct current stimulation (tDCS) and its impact over physical performance in recent years. This umbrella review examines meta-analyses to evaluate tDCS's impact on exercise performance in healthy individuals. We identified 9 meta-analyses that met our inclusion criteria, encompassing 50 crossover studies and 683 participants.

Assessing the Evidential Value of Mental Fatigue and Exercise Research.

It has often been reported that mental exertion, presumably leading to mental fatigue, can negatively affect exercise performance; however, recent findings have questioned the strength of the effect. To further complicate this issue, an overlooked problem might be the presence of publication bias in studies using underpowered designs, which is known to inflate false positive report probability and effect size estimates. Altogether, the presence of bias is likely to reduce the evidential value of the published literature on this topic, although it is unknown to what extent.

Individualized Mental Fatigue Does Not Impact Neuromuscular Function and Exercise Performance.

Introduction: Recent studies have questioned previous empirical evidence that mental fatigue negatively impacts physical performance. The purpose of this study was to investigate the critical role of individual differences in mental fatigue susceptibility by analyzing the neurophysiological and physical responses to an individualized mental fatigue task.

Methods: In a preregistered ( https://osf.

An umbrella review of randomized control trials on the effects of physical exercise on cognition.

Extensive research links regular physical exercise to an overall enhancement of cognitive function across the lifespan. Here we assess the causal evidence supporting this relationship in the healthy population, using an umbrella review of meta-analyses limited to randomized controlled trials (RCTs). Despite most of the 24 reviewed meta-analyses reporting a positive overall effect, our assessment reveals evidence of low statistical power in the primary RCTs, selective inclusion of studies, publication bias and large variation in combinations of pre-processing and analytic decisions.

The effect of benzodiazepines on exercise in healthy adult participants: A systematic review.

The use of benzodiazepines among athletes is a new and growing phenomenon according to the recent case reports published. Therefore, there is an urgent need to identify if there is rationale for the use of benzodiazepines and its effects on exercise. This review aims to provide an overview of the effects of benzodiazepine in exercise among healthy adult participants and if they might have an additional ergogenic or ergolytic effect.

Correction: Mental Fatigue Might be Not So Bad for Exercise Performance After All: A Systematic Review and Bias-Sensitive Meta-Analysis.

[This corrects the article DOI: 10.5334/joc.126.

Novel evidence on the effect of tramadol on self-paced high-intensity cycling.

The use of tramadol is a controversial topic in cycling. In order to provide novel evidence on this issue, we tested 29 participants in a pre-loaded cycling time trial (TT; a 20-min TT preceded by 40-min of constant work-rate at 60% of the VO) after ingesting 100 mg of tramadol (vs placebo and paracetamol (1.5 g)).

Mental Fatigue Might Be Not So Bad for Exercise Performance After All: A Systematic Review and Bias-Sensitive Meta-Analysis.

There is an ongoing debate in the scientific community regarding whether a state of mental fatigue may have a negative effect upon a range of objective and subjective measures of human performance. This issue has attracted attention from several fields, including sport and exercise sciences. In fact, a considerable body of literature in the sport science field has suggested that performing a long and demanding cognitive task might lead to a state of mental fatigue, impairing subsequent exercise performance, although research in this field has shown contradictory results.

Does mental fatigue impair physical performance? A replication study.

The aim of this study is to replicate the hypothesis that mental fatigue impairs physical performance in a pre-registered (https://osf.io/wqkap/) within-subjects experiment. 30 recreationally active adults completed a time-to-exhaustion test (TTE) at 80% VOmax in two separate sessions, after completing a mental fatigue task or watching a documentary for 90 min.

Correction: No evidence of the effect of cognitive load on self-paced cycling performance.

[This corrects the article DOI: 10.1371/journal.pone.

No evidence of the effect of cognitive load on self-paced cycling performance.

Objectives: To test the hypothesis that cognitive load (low vs. high load) during a 20 min self-paced cycling exercise affects physical performance.

Design: A pre-registered (https://osf.

Transcranial direct current stimulation (tDCS) over the left prefrontal cortex does not affect time-trial self-paced cycling performance: Evidence from oscillatory brain activity and power output.

Objectives: To test the hypothesis that transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (DLPFC) influences performance in a 20-min time-trial self-paced exercise and electroencephalographic (EEG) oscillatory brain activity in a group of trained male cyclists.

Design: The study consisted of a pre-registered (https://osf.io/rf95j/), randomised, sham-controlled, single-blind, within-subject design experiment.

Oscillatory brain activity during acute exercise: Tonic and transient neural response to an oddball task.

Intense physical exercise exerts measurable changes at various physiological levels that are well documented in the literature. However, despite the key role of the brain in processing inputs from internal organ systems and the external environment to coordinate and optimize behavior, little is known about brain dynamics during exercise. The present study investigates tonic and transient oscillatory brain activity in a group of participants performing an oddball task during a single bout of aerobic exercise.

The effects of transcranial direct current stimulation on objective and subjective indexes of exercise performance: A systematic review and meta-analysis.

Objective: To examine the effects of transcranial direct current stimulation (tDCS) on objective and subjective indexes of exercise performance.

Design: Systematic review and meta-analysis.

Data Sources: A systematic literature search of electronic databases (PubMed, Web of Science, Scopus, Google Scholar) and reference lists of included articles up to June 2018.

Effect of induced alkalosis on performance during a field-simulated BMX cycling competition.

Objectives: The aim of the present study was to test the effect of sodium bicarbonate (NaHCO) ingestion on performance during a simulated competition on a Bicycle Motocross (BMX) track.

Design: Double-blind cross-over study.

Methods: Twelve elite male BMX cyclists (age: 19.

Tramadol effects on physical performance and sustained attention during a 20-min indoor cycling time-trial: A randomised controlled trial.

Objectives: To investigate the effect of tramadol on performance during a 20-min cycling time-trial (Experiment 1), and to test whether sustained attention would be impaired during cycling after tramadol intake (Experiment 2).

Design: Randomized, double-blind, placebo controlled trial.

Methods: In Experiment 1, participants completed a cycling time-trial, 120-min after they ingested either tramadol or placebo.

Analgesics and Sport Performance: Beyond the Pain-Modulating Effects.

Unlabelled: Analgesics are used widely in sport to treat pain and inflammation associated with injury. However, there is growing evidence that some athletes might be taking these substances in an attempt to enhance performance. Although the pharmacologic action of analgesics and their use in treating pain with and without anti-inflammatory effect is well established, their effect on sport performance is debated.