Comparison of the Effects of Dual-Site Transcranial Direct Current and Pulsed Current Stimulation on Muscular Performance and Neurophysiological Responses in Submaximal Isotonic Contractions

Determining the effect of bilateral stimulation of direct current and transcranial pulsed current on muscle and cognitive function, and neurophysiological responses in submaximal isotonic contractions

A study with a within-group design, cross-balanced and double-blind. 15 subjects will be randomly exposed to 3 different conditions. In order to randomize the conditions, the website www.randomization.com will be used.

This study will be done in Razi University. After selecting the subjects and familiarizing themselves with the research process, each subject will be exposed to 3 different conditions of electrical stimulation of the brain in a random order, and then, they will perform three bouts of resistance activity until they reach exhaustion.

Criteria for entering the research: - Age range from 18 to 30 years - Women with a history of regular resistance exercises - Body mass index (BMI) 18.5 to 24.9 kilograms per square meter of height - Has natural vision for color recognition - Being right-handed (the dominant hand should be the right hand) Criteria for not entering the research: - Suffering from any cardiovascular, pulmonary and metabolic disease - History of seizures, epilepsy or other types of neurological diseases - Presence of implantable devices or pacemakers in the body - Smoking and alcohol consumption

This study is an intra-group and counterbalanced study, and subjects will be exposed to 3 different conditions of brain stimulation including: 1) direct current anodal stimulation, 2) pulse current anodal stimulation, 3) sham stimulation (placebo effect) . The duration of stimulation will be 20 minutes and its intensity will be 2 mA.

Muscle function, electromyography, pressure perception, cognitive and perceptual function

In this study, the order of subject exposure to 3 different conditions (3 different types of electrical stimulation of the brain) will be randomized by the Latin square method. For this purpose, a number between 1 and 15 will be randomly assigned to each of the subjects as an identification code using www.random.org. Then, the English letters B, A and C will be assigned to the three intervention conditions and a Latin square will be created. In this case, a Latin square with three rows and three columns is created. Finally, participants number 1 to 5 are placed in the sequence of the first row, participants number 6 to 10 are placed in the sequence of the second row, and participants number 11 to 15 are placed in the sequence of the third row.

In this double-blind study, the researcher and participants will be blinded to the type of transcranial electrical stimulation used in each session. In this study, the Neurostim stimulation device will be used to induce direct current electrical stimulation in three separate sessions and three different modes including: 1) direct current anodal stimulation, 2) pulsed current anodal stimulation, 3) sham stimulation (placebo effect) became. For this purpose, a person outside the research team will be responsible for applying electrical stimulation in three test sessions. In order to blind the participants, after they sit on a special chair, the stimulating device is hidden from their sight and is completely covered by a cover, and the electrodes are placed on the desired areas by the examiner. In order to blind the researcher, before the intervention, the researcher leaves the laboratory and returns to the test site after the stimulation period has passed and the electrodes are removed and the stimulation device is turned off. Also, in sham stimulation mode, according to standard protocols, active current is induced on the head for 30 seconds in order to induce the same sensation as in active stimulation mode, and then the current is cut off and the stimulation is deactivated.

All data can be shared after de-identifying the subjects.

6-9 months after printing the results

Head of the research team and executive researcher

Meta-analysis

If you need to receive documents, please send an email to Ehsan Amiri, head of research, at e.amiri@razi.ac.ir and Zahra Sayifi, lead researcher, at zahraseyfi6213@yahoo.com.

In case of an official request, the relevant reasons are announced and full details are mentioned, the data will be sent via email after 72 hours.