Exercise Dosing Trial for Individuals With Parkinson's Disease

Inclusion Criteria: * Subjects with idiopathic Parkinson Disease as determined by United Kingdom Brain Bank Criteria. This includes the presence of bradykinesia with one or both of the following: rest tremor and/or rigidity * Asymmetric onset of PD and progressive motor symptoms. * Hoehn and Yahr stage 2 or 3. * Stable dopaminergic medication regimen for 4 weeks prior to baseline visit with no anticipated changes for the duration of the study. * Stable doses of medications known to affect sleep and medications for Parkinson's Disease for at least 4 weeks prior to study entry without anticipation of medication change for the duration of the study. * Ability to complete exercise intervention and assessment visits during at least 16 weeks of intervention (3x/week for 16 weeks). * Must pass a physical examination to assess exercise readiness. * Women of childbearing potential may enroll but must use a reliable measure of contraception and have a negative serum pregnancy test at the screening visit. * Montreal Cognitive Assessment score ≥ 18 and ≤30. * Ability to pass a Physical Activity Readiness Questionnaire to assess exercise readiness. Exclusion Criteria: * Atypical features indicative of a Parkinson's Plus disorder (Progressive Supranuclear Palsy, Multiple Systems Atrophy, Corticobasal Degeneration) including cerebellar signs, supranuclear gaze palsy, apraxia, prominent autonomic failure, or other cortical signs. * Neuroleptic treatment at time of onset of Parkinsonism * Active treatment with a neuroleptic at time of study entry. Exceptions to this are quetiapine and clozapine. * History of multiple strokes with stepwise progression of Parkinsonism * History of multiple head injuries * Inability to walk without assistance, including a cane, wheelchair, or walker * Regular participation in an exercise program within the past 6 months. * Deep Brain Stimulation or other neurosurgical procedure for PD. * Untreated sleep apnea * Known narcolepsy * Participation in drug studies or the use of investigational drugs within 30 days prior to screening * Acute illness or active, confounding medical, neurological, or musculoskeletal conditions that, at the discretion of the PI, would prevent the subject's ability to participate in the study * Known contraindication to testing * Active alcoholism or other drug addiction * Pregnancy * Moderate to severe dementia