Wearable tDCS and Acute Golf Shot Performance

Participants are stratified by skill level (professional, amateur-high, amateur-middle) and sex, and randomly assigned 1:1 to real or sham stimulation using a computer-generated sequence; allocation is concealed from the testing team. Real stimulation: Halo Sport 2 headset, bilateral primary motor cortex (approximately C3/C4), 2 mA for 20 minutes (30-s ramp up and down), controlled by smartphone app. Sham: identical device and app procedure with a 30-s current ramp-up followed immediately by ramp-down and no sustained current; the app does not display the stimulation mode. Each participant attends one session: 10-min standardized warm-up, 40-shot pre-test, 20-min stimulation, 40-shot post-test. Shot outcomes (carry distance, ball speed, smash factor, spin rate, launch angle, launch direction, club speed, attack angle, face-to-path) are recorded with a TrackMan 4 launch monitor; within-player variability (SD of five shots) is computed per club category (Driver, 3-wood, hybrid, 5-iron, 7-iron, 9-iron, 70-yd wedge task, 100-yd wedge task). Analyses use linear mixed models with likelihood-ratio tests; skill-dependent moderation is tested categorically (group) and continuously (handicap linear and quadratic interactions) with false-discovery-rate correction. Anonymized participant-level data and analysis scripts will be made available in a public repository (Zenodo, https://doi.org/10.5281/zenodo.22684611).

Inclusion criteria

• Age ≥ 16 years;
• at least 2 years of systematic golf training;
• own set of clubs covering the standardized test clubs;
• right-handedness;
• normal or corrected-to-normal vision;
• no musculoskeletal injury in the previous 6 months that would affect the golf swing.

Exclusion criteria

• History of neurological or psychiatric disease; epilepsy;
• metal implants in the head; pregnancy;
• skin lesions under the electrode sites;
• current use of central-nervous-system-active medication;
• migraine within the previous year.