The purpose of the project is to investigate how moderate to high intensity aerobic exercise affects brain health in patients with Parkinson's disease. Assessments include MRI, blood markers, cognition, functional tests, questionnaires, and cardiorespiratory fitness.

The study will be a single blinded randomized controlled trial with a 6-month long intervention.

Background: No approved medical treatments preventing, delaying or stopping Parkinson's disease (PD) exist, making identification of interventions having this potential a major priority. Exercise studies have demonstrated beneficial effects of aerobic exercise (AE) on aerobic capacity, cognition, depression and the Unified Parkinson's Disease Rating Scale (UPDRS). Animal studies show that AE can reduce α-synuclein aggregation and toxin-induced lesions in the nigrostriatal pathway while improving motor and cognitive function. Consequently, AE possesses neuroprotective potentials and thus represents a potentially inexpensive and easily accessible disease modifying therapy in PD. Evolving magnetic resonance imaging (MRI) techniques offer valid and reliable biomarkers to monitor disease progression, but no longitudinal MRI study has assessed the neuroprotective potentials of AE in PD.

Aim: To investigate whether 24 weeks of AE can delay PD progression markers and improve motor/non-motor symptoms in PD.

Methods: 70 PD patients will be randomized 1:1 to 24 weeks of supervised AE (60 sessions, moderate to high intensity) or standard care. Neuroprotective effects will be determined by MRI scans (R2*, quantitative susceptibility mapping, diffusion kurtosis imaging, neuromelanin-weighted MRI, volumetry), blood markers and Levodopa equivalents. Clinical (MDS-UPDRS III) and subjective (MDS-UPDRS I) outcomes are also assessed.

Perspectives: By combining expertise from exercise physiology, radiology, endocrinology and neuropsychology a novel approach is taken aiming to understand the possible neuroprotective effects of AE in PD. This would be of high relevance to PD patients and their relatives. From a societal perspective it may lower disability-related costs by optimizing PD rehabilitation. In case of positive findings, this would provide the first convincing human evidence of a disease modifying effect of AE in PD potentially changing clinical practice.

Inclusion Criteria:

• Informed consent
• Age ≥ 40 years
• Idiopathic PD diagnosis (within the previous five years)
• Patients in symptomatic therapy / not in therapy. Patients who are not already taking medication are not expected to need medication within 6 months of inclusion (in case of drug startup, this is noted)
• Hoehn & Yahr ≤ 3
• Ability to transport oneself to and from exercise and testing

Exclusion Criteria:

• Alcohol abuse, depression, pacemaker
• Comorbidity/competing (neurological) disorder preventing participation in the intervention
• Pregnancy
• Metallic implants that prevent MRI.
• Expected exercise adherence below 85% of all planned sessions.
• Systematic moderate-high-level AE more than twice per week prior to start-up in the project