Parkinson's disease can cause slow or unsteady walking and balance problems that raise the risk of falls. This study will test whether adding a gentle, non-invasive brain stimulation called transcranial direct current stimulation (tDCS) during a supervised Nordic Walking program improves mobility in people with Parkinson's disease. Participants will be randomly assigned to receive either active tDCS or an inactive (sham) procedure that feels the same but does not deliver current, while both groups complete the same supervised walking program. Sessions occur three times per week for four weeks. We will measure walking speed with a 10-Meter Walk Test as the main outcome, and also evaluate balance, motor symptoms, quality of life, and any side effects. We expect that tDCS given during the walking sessions will help people walk faster and feel steadier compared with the walking program alone.
Idiopathic Parkinson's disease (e.g., UK Brain Bank criteria)
Hoehn & Yahr stage II-IV (on medication)
Stable antiparkinsonian medication for ≥4 weeks before enrollment
Slowed gait phenotype (e.g., ≥6 seconds on 10-Meter Walk at preferred speed)
Contraindications to tDCS: implanted cranial/brain devices (e.g., DBS), metal in the skull (excluding dental), active skin disease/lesions at electrode sites, uncontrolled epilepsy or history of seizure in the past 12 months
Unstable medical or psychiatric conditions that preclude safe participation (e.g., uncontrolled hypertension, recent cardiovascular events, severe orthostatic hypotension with syncope)
Severe freezing of gait or fall risk that prevents safe participation in supervised Nordic Walking, as judged by the clinical team
Severe musculoskeletal or vestibular disorders that limit walking with poles; severe uncorrected visual impairment