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Uehara L, Coelho DB, Baptista AF, Santana L, Moreira RJD, Zana Y, Malosá L, Lima T, Valentim G, Cardenas-Rojas A, Fregni F, Corrêa JCF, Corrêa FI. Does Transcranial Direct Current Stimulation reduce central and peripheral muscle fatigue in recreational runners? A triple-blind, sham-controlled, randomized, crossover clinical study. Braz J Phys Ther 2024; 28:101088. [PMID: 38936315 PMCID: PMC11260918 DOI: 10.1016/j.bjpt.2024.101088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 05/01/2024] [Accepted: 06/05/2024] [Indexed: 06/29/2024] Open
Abstract
BACKGROUND Runners seek health benefits and performance improvement. However, fatigue might be considered a limiting factor. Transcranial Direct Current Stimulation (tDCS) has been investigated to improve performance and reduce fatigue in athletes. While some studies showing that tDCS may improve a variety of physical measures, other studies failed to show any benefit. OBJECTIVE To evaluate the acute effects of tDCS on central and peripheral fatigue compared to a sham intervention in recreational runners. METHODS This is a triple-blind, controlled, crossover study of 30 recreational runners who were randomized to receive one of the two interventions, anodal or sham tDCS, after the fatigue protocol. The interventions were applied to the quadriceps muscle hotspot for 20 min. Peak torque, motor-evoked potential, and perceived exertion rate were assessed before and after the interventions, and blood lactate level was assessed before, during, and after the interventions. A generalized estimated equation was used to analyze the peak torque, motor-evoked potential, and blood lactate data, and the Wilcoxon test was used for perceived exertion rate data. RESULTS Our findings showed no difference between anodal tDCS and sham tDCS on peak torque, motor-evoked potential, blood lactate, and perceived exertion rate. CONCLUSION The tDCS protocol was not effective in improving performance and reducing fatigue compared to a sham control intervention. BRAZILIAN CLINICAL TRIALS REGISTRY RBR-8zpnxz.
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Affiliation(s)
- Laura Uehara
- Master's and Doctorate in Rehabilitation Sciences Program, Universidade Nove de Julho, São Paulo, SP, Brazil
| | | | | | - Lucas Santana
- Universidade Federal do ABC (UFABC), São Bernardo do Campo, SP, Brazil
| | | | - Yossi Zana
- Universidade Federal do ABC (UFABC), São Bernardo do Campo, SP, Brazil
| | - Luciana Malosá
- Master's and Doctorate in Rehabilitation Sciences Program, Universidade Nove de Julho, São Paulo, SP, Brazil
| | - Taiane Lima
- Master's and Doctorate in Rehabilitation Sciences Program, Universidade Nove de Julho, São Paulo, SP, Brazil
| | - Gabriela Valentim
- Master's and Doctorate in Rehabilitation Sciences Program, Universidade Nove de Julho, São Paulo, SP, Brazil
| | - Alejandra Cardenas-Rojas
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Felipe Fregni
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - João Carlos Ferrari Corrêa
- Master's and Doctorate in Rehabilitation Sciences Program, Universidade Nove de Julho, São Paulo, SP, Brazil
| | - Fernanda Ishida Corrêa
- Master's and Doctorate in Rehabilitation Sciences Program, Universidade Nove de Julho, São Paulo, SP, Brazil.
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Zhang F, Han Y, Wang H, Li Y, Tang D. Effects of transcranial direct current stimulation on motor learning in healthy elderly individuals: a systematic review and meta-analysis. Somatosens Mot Res 2024:1-11. [PMID: 38319133 DOI: 10.1080/08990220.2024.2310851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 01/02/2024] [Indexed: 02/07/2024]
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is widely used in motor recovery. Nevertheless, whether tDCS improves motor learning in healthy older adults is still controversial. This review aims to investigate the effectiveness of tDCS on motor learning in healthy elderly individuals. METHODS The PubMed, Cochrane Library, Web of Science and Embase databases were initially searched from inception to December 5, 2022. The standard mean difference (SMD) with the corresponding 95% confidence intervals (CIs) were analysed via random-effect models. RESULTS Compared with the sham group, no significant effects were found regarding improvement in motor learning based on the speed or accuracy of the task and reaction time for the tDCS intervention group. After subgroup analysis, a significant effect was found for improved motor learning based on reaction time in the primary motor cortex (M1)-cerebellar group. CONCLUSIONS This review revealed that tDCS had no significant effect on improving the speed or accuracy of motor learning in healthy elderly adults. However, it has a significant effect on improving the motor learning ability based on the reaction time of the task (mainly referring to the tDCS stimulation position of M1 and cerebellar), although the results have obvious heterogeneity and uncertainty.
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Affiliation(s)
- Fusheng Zhang
- College of Physical Education and Health, Guangxi Normal University, Guilin, China
- School of Physical Education, Zhaotong University, Zhaotong, China
| | - Yanbai Han
- College of Physical Education and Health, Guangxi Normal University, Guilin, China
| | - Hongli Wang
- College of Physical Education and Health, Guangxi Normal University, Guilin, China
| | - Yong Li
- College of Physical Education and Health, Guangxi Normal University, Guilin, China
| | - Dingyu Tang
- School of Physical Education, Zhaotong University, Zhaotong, China
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Dos Santos LF, Dos Santos Silva D, de Jesus Alves MD, Moura Pereira EV, do Nascimento HR, de Sousa Fernandes MS, de Freitas Zanona A, Knechtle B, Weiss K, Aidar FJ, de Souza RF. Acute effects of transcranial direct current stimulation (tDCS) on peak torque and 5000 m running performance: a randomized controlled trial. Sci Rep 2023; 13:9362. [PMID: 37291264 PMCID: PMC10250526 DOI: 10.1038/s41598-023-36093-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 05/29/2023] [Indexed: 06/10/2023] Open
Abstract
The benefits of transcranial direct current stimulation (tDCS) on brain function, cognitive response, and motor ability are well described in scientific literature. Nevertheless, the effects of tDCS on athletes' performance remain unclear. To compare the acute effects of tDCS on the running performance of 5000 m (m) runners. Eighteen athletes were randomized into Anodal (n = 9) groups that received tDCS for 20 min and 2 mA, and Sham (n = 9), in the motor cortex region (M1). Running time in 5000 m, speed, perceived exertion (RPE), internal load and peak torque (Pt) were evaluated. The Shapiro-Wilk test followed by a paired Student's t-test was used to compare Pt and total time to complete the run between the groups. The running time and speed of the Anodal group (p = 0.02; 95% CI 0.11-2.32; d = 1.24) was lower than the Sham group (p = 0.02, 95% CI 0.05-2.20; d = 1.15). However, no difference was found in Pt (p = 0.70; 95% CI - 0.75 to 1.11; d = 0.18), RPE (p = 0.23; 95% CI - 1.55 to 0.39; d = 0.60) and internal charge (p = 0.73; 95% CI - 0.77 to 1.09; d = 0.17). Our data indicate that tDCS can acutely optimize the time and speed of 5000 m runners. However, no alterations were found for Pt and RPE.
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Affiliation(s)
- Leila Fernanda Dos Santos
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Graduate Program in Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports-GEPEPS, Federal University of Sergipe (UFS), São Cristovão, Brazil
| | - Devisson Dos Santos Silva
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Graduate Program in Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports-GEPEPS, Federal University of Sergipe (UFS), São Cristovão, Brazil
| | - Micael Deivison de Jesus Alves
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Graduate Program in Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports-GEPEPS, Federal University of Sergipe (UFS), São Cristovão, Brazil
| | | | - Hortência Reis do Nascimento
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Graduate Program in Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports-GEPEPS, Federal University of Sergipe (UFS), São Cristovão, Brazil
| | | | | | - Beat Knechtle
- Institute of Primary Care, University of Zurich, 8091, Zurich, Switzerland.
- Medbase St. Gallen Am Vadianplatz, Vadianstrasse 26, 9001, St. Gallen, Switzerland.
| | - Katja Weiss
- Graduate Program in Neuropsychiatry and Behavioral Sciences, Federal University of Pernambuco (UFPE), Recife, Brazil
| | - Felipe J Aidar
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Graduate Program in Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports-GEPEPS, Federal University of Sergipe (UFS), São Cristovão, Brazil
| | - Raphael Fabricio de Souza
- Department of Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Graduate Program in Physical Education, Federal University of Sergipe (UFS), São Cristóvão, Brazil
- Group of Studies and Research of Performance, Sport, Health and Paralympic Sports-GEPEPS, Federal University of Sergipe (UFS), São Cristovão, Brazil
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Savoury RB, Kibele A, Power KE, Herat N, Alizadeh S, Behm DG. Reduced isometric knee extensor force following anodal transcranial direct current stimulation of the ipsilateral motor cortex. PLoS One 2023; 18:e0280129. [PMID: 36608054 PMCID: PMC9821721 DOI: 10.1371/journal.pone.0280129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 12/20/2022] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The goal of this study was to determine if 10-min of anodal transcranial direct current stimulation (a-tDCS) to the motor cortex (M1) is capable of modulating quadriceps isometric maximal voluntary contraction (MVC) force or fatigue endurance contralateral or ipsilateral to the stimulation site. METHODS In a randomized, cross-over design, 16 (8 females) individuals underwent two sessions of a-tDCS and two sham tDCS (s-tDCS) sessions targeting the left M1 (all participants were right limb dominant), with testing of either the left (ipsilateral) or right (contralateral) quadriceps. Knee extensor (KE) MVC force was recorded prior to and following the a-tDCS and s-tDCS protocols. Additionally, a repetitive MVC fatiguing protocol (12 MVCs with work-rest ratio of 5:10-s) was completed following each tDCS protocol. RESULTS There was a significant interaction effect for stimulation condition x leg tested x time [F(1,60) = 7.156, p = 0.010, ηp2 = 0.11], which revealed a significant absolute KE MVC force reduction in the contralateral leg following s-tDCS (p < 0.001, d = 1.2) and in the ipsilateral leg following a-tDCS (p < 0.001, d = 1.09). A significant interaction effect for condition x leg tested [F(1,56) = 8.12, p = 0.006, ηp2 = 0.13], showed a significantly lower ipsilateral quadriceps (to tDCS) relative MVC force with a-tDCS, versus s-tDCS [t(15) = -3.07, p = 0.016, d = -0.77]. There was no significant difference between the relative contralateral quadriceps (to tDCS) MVC force for a-tDCS and s-tDCS. Although there was an overall significant [F(1,56) = 8.36, p < 0.001] 12.1% force decrease between the first and twelfth MVC repetitions, there were no significant main or interaction effects for fatigue index force. CONCLUSION a-tDCS may be ineffective at increasing maximal force or endurance and instead may be detrimental to quadriceps force production.
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Affiliation(s)
- Ryan B. Savoury
- School of Human Kinetic and Recreation, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Armin Kibele
- Institute for Sport and Sport Science, University of Kassel, Kassel, Germany
| | - Kevin E. Power
- School of Human Kinetic and Recreation, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Nehara Herat
- School of Human Kinetic and Recreation, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Shahab Alizadeh
- School of Human Kinetic and Recreation, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - David G. Behm
- School of Human Kinetic and Recreation, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
- * E-mail:
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Marinus N, Van Hoornweder S, Aarts M, Vanbilsen J, Hansen D, Meesen R. The influence of a single transcranial direct current stimulation session on physical fitness in healthy subjects: a systematic review. Exp Brain Res 2023; 241:31-47. [PMID: 36357590 PMCID: PMC9648891 DOI: 10.1007/s00221-022-06494-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 10/20/2022] [Indexed: 11/12/2022]
Abstract
Physical fitness is of indisputable importance for both health, and sports. Currently, the brain is being increasingly recognized as a contributor to physical fitness. Hereby, transcranial direct current stimulation (tDCS), as an ergogenic aid, has gained scientific interest. The current PRISMA-adherent review aimed to examine the effect of tDCS on the three core components of physical fitness: muscle strength, -endurance and cardiopulmonary endurance. Randomized controlled- or cross-over trials evaluating the effect of a single tDCS session (vs. sham) in healthy individuals were included. Hereby, a wide array of tDCS-related factors (e.g., tDCS montage and dose) was taken into account. Thirty-five studies (540 participants) were included. Between-study heterogeneity in factors such as age, activity level, tDCS protocol, and outcome measures was large. The capacity of tDCS to improve physical fitness varied substantially across studies. Nevertheless, muscle endurance was most susceptible to improvements following anodal tDCS (AtDCS), with 69% of studies (n = 11) investigating this core component of physical fitness reporting positive effects. The primary motor cortex and dorsolateral prefrontal cortex were targeted the most, with positive results being reported on muscle and cardiopulmonary endurance. Finally, online tDCS seemed most beneficial, and no clear relationship between tDCS and dose-related parameters seemed present. These findings can contribute to optimizing tDCS interventions during the rehabilitation of patients with a variety of (chronic) diseases such as cardiovascular disease. Therefore, future studies should focus on further unraveling the potential of AtDCS on physical fitness and, more specifically, muscle endurance in both healthy subjects and patients suffering from (chronic) diseases. This study was registered in Prospero with the registration number CRD42021258529. "To enable PROSPERO to focus on COVID-19 registrations during the 2020 pandemic, this registration record was automatically published exactly as submitted. The PROSPERO team has not checked eligibility".
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Affiliation(s)
- Nastasia Marinus
- Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Agoralaan Building A 3590, Diepenbeek, Belgium. .,Biomedical Research Center, Hasselt University, Diepenbeek, Belgium.
| | - Sybren Van Hoornweder
- Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Agoralaan Building A 3590, Diepenbeek, Belgium
| | - Marthe Aarts
- Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Agoralaan Building A 3590, Diepenbeek, Belgium
| | - Jessie Vanbilsen
- Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Agoralaan Building A 3590, Diepenbeek, Belgium
| | - Dominique Hansen
- Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Agoralaan Building A 3590, Diepenbeek, Belgium.,Biomedical Research Center, Hasselt University, Diepenbeek, Belgium.,Heart Centre Hasselt, Jessa Hospital, Hasselt, Belgium
| | - Raf Meesen
- Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Agoralaan Building A 3590, Diepenbeek, Belgium.,Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Louvain, Belgium
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Savoury R, Kibele A, Behm DG. Methodological Issues with Transcranial Direct Current Stimulation for Enhancing Muscle Strength and Endurance: A Narrative Review. JOURNAL OF COGNITIVE ENHANCEMENT 2021. [DOI: 10.1007/s41465-021-00222-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Lerma-Lara S, De Cherade Montbron M, Guérin M, Cuenca-Martínez F, La Touche R. Transcranial direct-current stimulation (tDCS) in the primary motor cortex and its effects on sensorimotor function: a quasi-experimental single-blind sham-controlled trial. Sci Rep 2021; 11:6566. [PMID: 33753853 PMCID: PMC7985198 DOI: 10.1038/s41598-021-85989-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 03/09/2021] [Indexed: 11/25/2022] Open
Abstract
The main aim was to assess the short-term effects of active-tDCS (a-tDCS) in the primary motor cortex (anodal stimulation-M1) on sensorimotor variables. These variables included discriminative sensation through the two-point discrimination (2-PD) test, tactile acuity threshold and pressure pain threshold (PPT), and electromyographic (EMG) activity compared with a sham-tDCS (s-tDCS) in healthy individuals. A total of 100 participants were included. Fifty of the participants received the a-tDCS application of 2 mA for 20 min, whereas the remaining fifty received the s-tDCS. The 2-PD and tactile acuity threshold in thenar eminence of the hand and in the dorsal part of the foot and also, PPT and EMG activity during maximal voluntary contraction in the biceps brachii and rectus femoris were assessed before and after the tDCS application. The a-tDCS intervention was not significantly superior to the s-tDCS in any variable. However, significant within-group pre- and post-intervention differences were found in the a-tDCS, such as the tactile acuity threshold in thenar eminence of the hand, with a small effect size (p = .012, d = 0.20) and in the PPT of the rectus femoris, also with a small effect size (p = .001, d = - 0.17). Regarding EMG activity, a trend towards greater activity was observed in participants with a-tDCS compared with s-tDCS, which showed a trend towards decreased EMG activity. In fact, although no differences were found between the groups, within-group differences were statistically significant in the biceps brachii pre- and postintervention (p = .023, d = - 0.16, and p = .002, d = 0.18, respectively), and also in the rectus femoris, only in the a-tDCS, with a small effect size (p = .011, d = - 0.14). This study showed no significant between-group differences in sensorimotor outcomes. A single session of tDCS in isolation appears to produce immediate effects in healthy participants on sensorimotor function; however, these effects were very small.
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Affiliation(s)
- Sergio Lerma-Lara
- Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, C/ La Salle, No. 10, 28023, Madrid, Spain.
- Motion in Brains Research Group, Institute of Neuroscience and Sciences of the Movement (INCIMOV), Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain.
- Hospital Infantil Universitario Niño Jesús, Madrid, Spain.
| | - Marina De Cherade Montbron
- Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, C/ La Salle, No. 10, 28023, Madrid, Spain
| | - Mathias Guérin
- Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, C/ La Salle, No. 10, 28023, Madrid, Spain
| | - Ferran Cuenca-Martínez
- Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, C/ La Salle, No. 10, 28023, Madrid, Spain.
- Motion in Brains Research Group, Institute of Neuroscience and Sciences of the Movement (INCIMOV), Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain.
| | - Roy La Touche
- Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, C/ La Salle, No. 10, 28023, Madrid, Spain
- Motion in Brains Research Group, Institute of Neuroscience and Sciences of the Movement (INCIMOV), Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
- Instituto de Neurociencia y Dolor Craneofacial (INDCRAN), Madrid, Spain
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Workman CD, Fietsam AC, Rudroff T. Different Effects of 2 mA and 4 mA Transcranial Direct Current Stimulation on Muscle Activity and Torque in a Maximal Isokinetic Fatigue Task. Front Hum Neurosci 2020; 14:240. [PMID: 32714170 PMCID: PMC7344304 DOI: 10.3389/fnhum.2020.00240] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 06/02/2020] [Indexed: 12/13/2022] Open
Abstract
Studies investigating the effects of transcranial direct current stimulation (tDCS) on fatigue and muscle activity have elicited measurable improvements using stimulation intensities ≤2 mA and submaximal effort tasks. The purpose of this study was to determine the effects of 2 mA and 4 mA anodal tDCS over the primary motor cortex (M1) on performance fatigability and electromyographic (EMG) activity of the leg muscles during a maximal isokinetic task in healthy young adults. A double-blind, randomized, sham-controlled crossover study design was applied. Twenty-seven active young adults completed four sessions, each spaced by 5-8 days. During session 1, dominance was verified with isokinetic strength testing, and subjects were familiarized with the fatigue task (FT). The FT protocol included 40 continuous maximum isokinetic contractions of the knee extensors and flexors (120°/s, concentric/concentric). During Sessions 2-4, tDCS was applied for 20 min with one of three randomly assigned intensities (sham, 2 mA or 4 mA) and the FT was repeated. The anode and cathode of the tDCS device were placed over C3 and the contralateral supraorbital area, respectively. A wireless EMG system collected muscle activity during the FT. The 2 mA tDCS condition had significantly less torque (65.9 ± 32.7 Nm) during the FT than both the sham (68.4 ± 33.9 Nm, p < 0.001) and 4 mA conditions (68.4 ± 33.9 Nm, p = 0.001). Furthermore, the 2 mA condition (33.8 ± 11.7%) had significantly less EMG activity during the FT than both the sham (39.7 ± 10.6%, p < 0.001) and 4 mA conditions (40.5 ± 13.4%, p = 0.001). Contrary to previous submaximal isometric fatigue investigations, the 2 mA tDCS condition significantly reduced torque production and EMG activity of the leg extensors during a maximal isokinetic FT compared with the sham and 4 mA conditions. Also, torque production and EMG activity in the 4 mA condition were not significantly different from sham. Thus, the effects of tDCS, and the underlying mechanisms, might not be the same for different tasks and warrants more investigation.
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Affiliation(s)
- Craig David Workman
- Department of Health and Human Physiology, College of Liberal Arts and Sciences, University of Iowa, Iowa City, IA, United States
| | - Alexandra C Fietsam
- Department of Health and Human Physiology, College of Liberal Arts and Sciences, University of Iowa, Iowa City, IA, United States
| | - Thorsten Rudroff
- Department of Health and Human Physiology, College of Liberal Arts and Sciences, University of Iowa, Iowa City, IA, United States.,Department of Neurology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, IA, United States
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Giboin LS, Gruber M. Neuromuscular Fatigue Induced by a Mixed Martial Art Training Protocol. J Strength Cond Res 2019; 36:469-477. [PMID: 31895287 DOI: 10.1519/jsc.0000000000003468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Giboin, L-S and Gruber, M. Neuromuscular fatigue induced by a mixed martial art training protocol. J Strength Cond Res XX(X): 000-000, 2019-Mixed martial arts (MMA) is a full-contact sport whose popularity and professionalism are rapidly growing. However, the specific physiological demands of this sport have been only scarcely studied so far, and especially the amount or type of neuromuscular fatigue induced by an MMA bout remains completely unknown. We estimated neuromuscular fatigue of knee extensors muscles during and after an MMA training protocol designed to simulate the physiological demands of MMA competition in competitive practitioners (n = 9) with isometric maximal voluntary force (MVF), potentiated muscle twitch at rest (Ptw), and voluntary activation (VA). Bayesian linear mixed models showed that the training protocol induced a reduction of MVF, Ptw, and VA. Although the largest reduction across time of VA was smaller than the largest reduction of Ptw, an effect of VA, but not of Ptw, was found on MVF variation. The training protocol induced neuromuscular fatigue, with a larger peripheral (Ptw) than central component (VA). However, despite the large decrease in Ptw, force production capacity was related only to VA, indicating that central control might play an important role in the compensation of the peripheral fatigue components estimated with Ptw. This central compensation can most probably prevent a too large loss of muscle force during the training protocol.
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Affiliation(s)
- Louis-Solal Giboin
- Human Performance Research Center, Sensorimotor Performance Lab, University of Konstanz, Konstanz, Germany
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10
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Mesquita PHC, Lage GM, Franchini E, Romano-Silva MA, Albuquerque MR. Bi-hemispheric anodal transcranial direct current stimulation worsens taekwondo-related performance. Hum Mov Sci 2019; 66:578-586. [PMID: 31254810 DOI: 10.1016/j.humov.2019.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 12/11/2022]
Abstract
Transcranial Direct Current Stimulation (tDCS) is a neuromodulatory technique that has been used as an ergogenic aid in exercise/sports performance. However, little is known about its effects on highly-trained subjects, as athletes. The present study aimed to verify the effects of bi-hemispheric anodal tDCS (a-tDCS) on the performance of taekwondo athletes. Additionally, we investigated the persistence of the effects of the a-tDCS one hour after it. Nineteen Taekwondo athletes received active or sham bi-hemispheric a-tDCS over the primary motor cortex (M1). a-tDCS was delivered at 1.5 mA for 15 min. Athletes performed Countermovement Jumps (CMJ) and the Frequency Speed of Kick Test (FSKT) immediately (Mo1) and one hour after stimulation (Mo2). The athletes also reported their session-rating of perceived exertion (session-RPE). The total number of kicks (TK) was higher in sham than in the active a-tDCS condition (p < 0.01). In addition, TK was higher at Mo2 than at Mo1 (p < 0.05). Similarly, the session-RPE was higher in the a-tDCS condition (p < 0.05) and was greater one-hour post-stimulation (p < 0.01). No differences were found for CMJ performance (p > 0.05). Thus, bi-hemispheric a-tDCS worsens performance of taekwondo athletes, and the effect remains present even 1 h after the stimulation.
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