Inclusion Criteria:  Age > 18years Confirmed diagnosis of Parkinson's Disease Hoehn and Yahr stage 1 to 3 Stable course of disease-modifying therapy over the past 3 months Mini Mental State Examination > 24 Physician approval for exercise Stable deep brain stimulation setting for the past year Demonstrate a need for functional rehabilitation  Exclusion Criteria:  • Severe dyskinesia or severe on-off phenomenon  Unstable medication regiment Any co-morbidity that will interfere with walking Conventional physical therapy or G-EO training within the past 6 months Height <1m or >2m Body weight >150 kg Contraindications to G-EO gait training (e.g., bone instability)