The Effects of Combined Transcranial Direct Current Stimulation and Pneumatic Compression on Selected Recovery Parameters After a 10K Run
Phase: NA
Conditions: Recovery Methods, Muscle Fatigue, Exercise Performance Recovery, Endurance Exercise
Sponsor: Uludag University

Study Protocol and Statistical Analysis Plan 
 
 
Title: The Effects of Combined Transcranial Direct Current Stimulation and Pneumatic 
Compression on Selected Recovery Parameters After a 10K Run 
NCT Number: Pending 
Ethics Committee Approval Number: 2025-17/11 
Date: 16 December 2025 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
Objectives and Hypotheses 
Research Question: 
In this context, the primary research question is: 
" How do transcranial direct current stimulation (tDCS), pneumatic compression (PC), and 
their combined application affect subjective well-being, total quality of recovery (TQR), heart 
rate variability (HRV), neuromuscular performance (maximal voluntary isometric contraction 
and vertical jump), and cognitive function (Stroop Test) in master male long-distance runners 
aged 40–55, immediately before, immediately after a 10-kilometer (10K) run, and following a 
20-minute recovery intervention? 
Hypotheses: 
 
H1: tDCS application will significantly improve post-run recovery markers, including 
subjective well-being, TQR, HRV, neuromuscular performance, and cognitive 
function. 
 
H2: PC application will significantly improve post-run recovery markers, including 
subjective well-being, TQR, HRV, neuromuscular performance, and cognitive 
function. 
 
H3: Combined application of tDCS and PC will produce greater improvements in 
recovery markers compared to either intervention applied individually. 
Objective: 
The aim of this study is to evaluate the effects of tDCS, PC, and their combined application on 
physical, physiological, psychological, and cognitive recovery in master male long-distance 
runners after a 10K run, with the goal of shortening recovery time and preventing performance 
decline following intensive exercise. 
Specific Aims: 
 
To investigate the effects of tDCS and PC and combined tDCS+PC on post-run 
muscle fatigue and neuromuscular performance (maximal voluntary isometric 
contraction and vertical jump). 
 
To examine changes in subjective well-being and TQR as indicators of psychological 
recovery. 
 
To assess cognitive recovery using the Stroop test. 
 
To analyze physiological responses by evaluating HRV following each intervention.  
 
To compare the individual and combined contributions of tDCS and PC to overall 
recovery. 
 
 
 
 
 

Method 
The aim of this study is to investigate the effects of combined tDCS and PC on recovery in 
master male runners following a 10K run. The study also aims to examine whether these 
interventions can shorten recovery time and prevent performance decline after prolonged and 
intense exercise. 
This study will be conducted as a randomized, controlled, crossover trial using a mixed 
experimental design. Each participant will undergo four different recovery protocols in a 
randomized order, with a one-week interval between sessions. Randomization will be 
performed using Research Randomizer (https://www.randomizer.org/), assigning participants 
to one of four sequences (e.g., B–A–D–C). Participants will be identified only by numerical 
codes to ensure blinding and maintain confidentiality. Each participant will experience all 
protocols, allowing within-subject comparisons and minimizing order-related bias. 
The four recovery protocols are: 
(A) tDCS group: transcranial direct current stimulation only 
(B) PC group: pneumatic compression only 
(C) tDCS + PC group: simultaneous application of both tDCS and PC 
(D) Control group: passive rest with no intervention 
tDCS and PC interventions represent the independent variables, while dependent variables 
include WBQ, TQR, HRV, Stroop Test, vertical jump, and MVIC with EMG recordings. 
Participants will be 35 male long-distance master runners aged 40–55, residing in Bursa, 
Turkey, with at least five years of consistent training. They will train five days per week, 90 
minutes per day, and must meet aerobic fitness criteria established by the American College of 
Sports Medicine, completing official 10K race under 50 minutes within last six months and 
maintain a weekly running volume of 60-80 km. Volunteers will be recruited from the local 
long-distance running community familiar to the principal investigator, Hilal Oruç Kaya. 
Participants will be excluded if they have used regular medications within the last six months, 
consumed stimulants, caffeine, or alcohol within 24 hours prior to testing, smoke, have 
experienced musculoskeletal injuries in the past six months, are currently undergoing physical 
therapy, or have neurological conditions such as epilepsy or seizure history, or possess cardiac, 
brain, or other electronic implants. Additional exclusion criteria include open wounds or 
dermatological conditions on the head, circulatory disorders such as deep vein thrombosis, 
peripheral arterial disease, severe varicose veins, or prior exposure to tDCS or PC interventions. 
Participants may withdraw voluntarily, fail to attend sessions, or be removed if cardiovascular, 
neurological, or orthopedic complications occur during exercise or interventions, or if they 
experience excessive discomfort or adverse effects from the tDCS or PC procedures. Written 
informed consent will be obtained after explaining the study’s purpose, procedures, potential 
risks, and benefits. Sample size was calculated using G*Power 3.1.9.7 for repeated measures 
ANOVA with within-between interaction, effect size f = 0.30, α = 0.05, power = 0.80, resulting 
in n = 28. Accounting for potential dropouts, 35 participants will be recruited. 
 
Screening and Familiarization Session: 
Participants will undergo anthropometric measurements (weight, body fat, height) using 
Tanita BC 418 MA and Seca stadiometer. Physical fitness will be evaluated with a 12-minute 
Cooper Test on a 400 m track under controlled conditions (temperature 20–24°C, relative 

humidity 50–70%, wind ≤10 km/h). A 20-minute warm-up including jogging, accelerations, 
jumps, and stretching will precede testing. Distances will be recorded with a Polar V3 GPS 
watch. 
Participants will also complete a familiarization session with the 10K course, tDCS and PC 
devices, Stroop Test, MVIC, and vertical jump measurements to ensure procedural 
understanding. 
Experimental Sessions 
Pre-run Measurements (T1): Immediately prior to the 10K run, participants will complete the 
TQR, and the WBQ in the gym. Following this, the Polar Vantage V3 GPS-enabled watch and 
H10 heart rate strap will be fitted to each participant, and HRV data will be recorded for 5 
minutes in a seated position. 
After HRV recording, participants will perform the Stroop test under researcher supervision 
using a computer. Subsequently, vertical jump performance will be assessed. Participants will 
start from an upright standing position, perform a preliminary downward squat by flexing the 
knees and hips, and immediately extend the knees and hips to jump vertically. Vertical jump 
measurements will be performed three times with a 1-minute interval between trials, and the 
results will be recorded. 
Following the jump assessment, participants will be fitted with an EMG device for the MVIC 
test. EMG signals will be recorded from the Vastus Lateralis, Rectus Femoris, and Vastus 
Medialis muscles during the test. 
10K Run: After Test-1, participants will complete a 10K run on the athletics track at Bursa 
Uludağ University (BUU). The route begins and ends at the Faculty of Sports Sciences, BUÜ. 
Participants will have 30 minutes for individual warm-up and preparation. 
The run will be performed at 75% intensity, determined using the Karvonen method, based on 
each participant’s maximum heart rate obtained during an on-field Cooper test. Target heart 
rate zones will be set with a ±5 bpm tolerance. GPS and HRV tracking will be conducted using 
the Polar Vantage V3 watch. Additionally, perceived exertion will be assessed verbally using 
the Borg-20 scale at the 5K mark and immediately after completing the run, with responses 
recorded by the researchers. 
Post-run Measurements (T2): Immediately after completing the 10K run, the procedures 
conducted in Test 1 will be repeated. 
Interventions: 
Participants will be randomly assigned to one of four protocols: 
 
(A) tDCS: Participants assigned to the tDCS intervention will receive stimulation using 
the Brain Premier tDCS device. During the application, participants will be positioned 
in a semi-recumbent posture at approximately 45° recline, and the device will be 
adjusted accordingly. Anode and cathode electrodes, embedded in 5×5 cm saline-
soaked sponge pads, will be placed over the F3 (left dorsolateral prefrontal cortex) and 
F4 (right dorsolateral prefrontal cortex) locations according to the international 10–20 
EEG system. Stimulation will be delivered at a constant current intensity of 2 mA for 
20 minutes.  

 
(B) Pneumatic Compression (PC): Participants assigned to the PC intervention will 
receive lower-limb pneumatic compression using the Normatec device. They will be 
positioned in a semi-recumbent posture at approximately 45° recline, and the device 
will be adjusted to match this posture. Compression will last for 20 minute. Specifically, 
the most distal chamber (cell 1, ankle level) will receive 70 mmHg pulse pressure; the 
intermediate chambers (cells 2–4) will receive 80 mmHg; and the most proximal 
chamber (cell 5) will receive 60 mmHg. Each chamber will undergo 30 seconds of 
pulsed compression followed by 30 seconds of static hold. Chambers will inflate and 
deflate sequentially from distal to proximal to create a peristaltic compression pattern. 
This method aims to enhance intramuscular fluid dynamics, promote venous return, and 
facilitate the removal of metabolic by products.  
 
(C) Combined tDCS + PC: Participants in the combined intervention group will 
simultaneously receive tDCS and PC for 20 minutes while positioned in a semi-
recumbent posture at approximately 45° recline. tDCS will be applied via 5×5 cm 
saline-soaked sponge electrodes over F3 and F4 regions using the Brain Premier CE-
certified device at 2 mA. Electrode contact quality will be monitored via the device 
interface to ensure safety and adherence to protocol parameters. PC will be applied 
concurrently using the Normatec device. Distal cell (cell 1) will receive 70 mmHg, 
intermediate cells (cells 2–4) 80 mmHg, and proximal cell (cell 5) 60 mmHg pulse 
pressure. Each chamber will follow 30 seconds of pulsed compression and 30 seconds 
of static hold, proceeding in a distal-to-proximal sequential pattern to create a peristaltic 
flow. This synchronized intervention aims to provide a holistic recovery effect by 
targeting both peripheral and central mechanisms of recovery. 
 
(D) Control: Participants in the control group will be positioned in a semi-recumbent 
posture at approximately 45° recline for 20 minutes without receiving any intervention. 
During this period, participants will remain passive in a quiet, distraction-free 
environment. The 45° semi-recumbent posture is consistent with the intervention groups 
to control for physiological variations arising from body positioning (e.g., blood flow, 
venous return, postural hemodynamic changes). Active recovery strategies (e.g., 
walking, stretching) were deliberately excluded to avoid potential confounding effects. 
This standardized passive rest condition allows for a valid comparison of intervention 
effects between groups. 
Post-intervention Measurements (T3): The procedures conducted in Test 1 will be repeated 
immediately after the participant completes the assigned intervention protocol. 
Outcome Measures: 
 
Subjective scales: Well-being Questionnaire, Total Quality Recovery 
 
Heart rate variability (HRV) and GPS 
 
Cognitive performance via Stroop Test 
 
Vertical jump height via My Jump app 
 
MVIC with EMG on quadriceps muscles following SENIAM protocol 
 
tDCS and PC applied according to standardized protocols 

Statistical Analysis 
Data will be analyzed with IBM SPSS 29. Normality (Shapiro-Wilk), homogeneity (Levene), 
and sphericity (Mauchly) will be tested. Two-way repeated measures ANOVA (4 Time × 4 
Group) will assess interactions, with Bonferroni post-hoc tests. Effect sizes will be reported 
using partial eta squared (ƞ_p²): small (>0.01), medium (>0.06), large (>0.14). Significance 
threshold p < 0.05. 
This study will provide comprehensive insight into the effects of tDCS and PC, alone and in 
combination, on recovery in older endurance athletes, contributing evidence-based 
recommendations for optimizing performance and minimizing injury risk.