Cognitive Effects of Exercise in Parkinson's Disease

Participants will be assigned to either the HIIT group, which will engage in 3 classes per week, or a standard-of-care control group, which will include people who will continue their standard care and usual physical activities but do not plan on partaking in additional structured exercise interventions for 3 months (except for physical and occupational therapy if medically necessary). Cognitive functions will be measured using standardized tests (Stroop, Trail Making Test-B (TMT-B), verbal fluency (using letters F-A-S), and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS)), alongside assessing subjective ratings of daily cognitive function using the Neuro Quality of Life - Cognitive Function (Neuro-QoL CF) survey. Secondary outcomes will include self-efficacy measures, specifically regarding goal achievement, managing emotions and daily activities. We will also aim to obtain brain functional MRI (fMRI) and neuromelanin-sensitive MRI (NM-MRI) data from a subset of participants to measure the brain effects of HIIT as exploratory outcomes.