The Effects of Different Montages of tDCS on Muscle Strength in Healthy Adults

Study Overview
=================
Brief Summary
-----------------
To investigate the effects of different montages of tDCS on muscle strength in healthy adults

Detailed Description
-----------------
Electrode montage or placement of tDCS over primary motor cortex can be categorized into unilateral (anodal or cathodal electrode over primary motor area) and bilateral tDCS (both anodal and cathodal electrode over the cortex). Previous studies reported benefits of different tDCS montages on muscle performance in healthy participants. However, there is no guideline for tDCS montages. This study aims to investigate immediate effects of different tDCS montages on muscle strength in healthy participants.

Official Title
-----------------
The Effects of Different Montages of Transcranial Direct Current Stimulation on Muscle Strength in Healthy Adults

Conditions
-----------------
Healthy

Intervention / Treatment
-----------------
* Device: Transcranial direct current stimulation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Healthy adults Age range between 18 - 60 years old Right-handed dominant identified by the Edinburg Handedness Inventory No recent muscle injuries of both limbs for a past 6-months Exclusion Criteria: Consumed caffeine within 24 hours prior the experiment History of neurological symptoms i.e. seizures, weakness, loss of sensation or unclear history of pass illness Present of metal implantation, intracranial shunt, cochlear implantation or cardiac pacemakers Present of opened wound or infectious wound around scalp

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Anodal-tDCS<br>Anodal transcranial direct current stimulation (tDCS) will be applied for 20 mins. Anode on the primary motor area (M1) of dominant hemisphere and Cathode on the supraorbital area of non-dominant hemisphere. Current intensity is fixed at 2 mA and current will flow continuously. The scope of intervention is to investigate effect of tDCS on muscle strength. | Device: Transcranial direct current stimulation<br>* Dual/Cathodal/Anodal/Sham tDCS will be applied in 2 mA, 20 mins. All experiments will be performed in random order for each subject.<br>|
| Experimental: Cathodal-tDCS<br>Cathodal transcranial direct current stimulation (tDCS) will be applied for 20 mins. Cathode on the primary motor area (M1) of non-dominant hemisphere and Anode on the supraorbital area of dominant hemisphere. Current intensity is fixed at 2 mA and current will flow continuously. The scope of intervention is to investigate effect of tDCS on muscle strength. | Device: Transcranial direct current stimulation<br>* Dual/Cathodal/Anodal/Sham tDCS will be applied in 2 mA, 20 mins. All experiments will be performed in random order for each subject.<br>|
| Experimental: Dual-tDCS<br>Dual transcranial direct current stimulation (tDCS) will be applied for 20 mins. Anode on the primary motor area (M1) of dominant hemisphere and Cathode on the primary motor area of non-dominant hemisphere. Current intensity is fixed at 2 mA and current will flow continuously. The scope of intervention is to investigate effect of tDCS on muscle strength. | Device: Transcranial direct current stimulation<br>* Dual/Cathodal/Anodal/Sham tDCS will be applied in 2 mA, 20 mins. All experiments will be performed in random order for each subject.<br>|
| Sham Comparator: Sham-tDCS<br>Dual transcranial direct current stimulation (tDCS) will be applied over C3-C4 or the motor area (M1) for 20 mins. Anode on dominant hemisphere, Cathode on non-dominant hemisphere. The scope of intervention is to investigate effect of tDCS on muscle strength. | Device: Transcranial direct current stimulation<br>* Dual/Cathodal/Anodal/Sham tDCS will be applied in 2 mA, 20 mins. All experiments will be performed in random order for each subject.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline muscle strength after tDCS | Muscle strength will be measured in Newton by using a hand-held dynamometer. | Baseline (Pretest) and 40 minutes ( posttest) |