This study will investigate the impact of two common exercise modalities, cardiovascular and resistance training, on sleep quality and architecture in persons with Parkinson's disease (PD), and whether these potential positive changes in sleep are associated with improvements in brain plasticity and different quality of life (QoL)-related aspects. Participants will perform either cardiovascular training (CT) or resistance training (RT) for 12 weeks, at least two times/week. The assessments will be performed at baseline and after training by an assessor blinded to the participants' group allocation.

Background: Over 100,000 Canadians are currently living with PD. Every year, 6.600 new cases are diagnosed and this number is expected to double by 2031. Most (98%) of those persons experience sleep problems, which can appear even before the onset of the cardinal motor symptoms of the disease, affecting multiple aspects of their QoL. Persons with PD also show alterations in sleep architecture, which have been associated with faster disease progression. Since medications used to reduce sleep problems in PD have potential adverse side effects, exercise has been proposed as a potential non-pharmacological alternative to improve sleep quality and architecture in people with PD. However, the most beneficial type of intervention to improve sleep in this clinical population is still to be determined.

Objective: 1) To conduct a 12-week RCT comparing the effects of CT and RT on both objective and subjective measures of sleep quality and architecture in patients with mild-to-moderate PD; 2) To assess whether, regardless of the type of exercise, positive changes in sleep quality and architecture mediate exercise-induced improvements in cognitive and motor function as well as in different aspects that directly impact on QoL; 3) To explore whether, regardless of the type of exercise used, positive changes in sleep architecture will be associated with improvements in brain plasticity and motor learning.

Design: a single-blinded RCT in which assessments will be performed at baseline (pre) and after (post) training by an assessor blinded to the participants' group allocation.

Outcomes: 1) objective and subjective sleep quality as well as sleep architecture; 2) cognitive and motor function as well as fatigue, psychological functioning, and QoL; 3) motor learning and brain plasticity.

Methods: Changes in objective (i.e. sleep efficiency) and subjective measures of sleep quality will be assessed with actigraphy and the PD sleep scale version 2, respectively. Sleep architecture will be measured with polysomnography. Motor and cognitive function will be assessed with the Unified PD Rating Scale and the Scale for Outcomes in PD-Cognition, respectively. Fatigue, psychosocial functioning and QoL will be assessed with the PD Fatigue Scale, the Scale for Outcomes in PD-Psychosocial and the PD QoL Scale, respectively. Motor learning will be assessed using a visuomotor tracking task; whereas brain plasticity will be measured with transcranial magnetic stimulation applied over the primary motor cortex.

Expected results: 1) CT will be more effective than RT in improving objective and subjective sleep quality. RT and CT will be equally effective in improving sleep architecture; 2) Improvements in sleep quality and architecture will be associated with enhancements in cognition, motor function and different QoL-related aspects; 3) Positive changes in sleep architecture will mediated increases in brain plasticity and motor learning.

Impact: This will be the first study comparing the effect of CT and RT on sleep quality and architecture and exploring associations with cognitive and motor function as well as aspects that directly impact QoL. The results of the study will provide important information to design more personalized exercise-based treatments, which are patient-oriented and aimed to mitigate sleep complains in this clinical population.

Inclusion Criteria:

• Persons with mild-moderate idiopathic Parkinson's Disease (Modified Hoehn & Yahr Scale stages 1-3);
• On a stable dosage of medication during the previous month;
• Having poor sleep quality defined as a score > 18 in the PDSS-2(scores above this cut-off value define clinically relevant sleep disorders);

Exclusion Criteria:

• Having atypical parkinsonism, dementia or any other neurological, psychiatric or cardiovascular comorbidity affecting the ability to perform exercise;
• Presenting severe untreated obstructive sleep apnea (OSA);
• Having a Montreal Cognitive Assessment (MoCA) score <21
• Having a Beck Depression Inventory (BDI version 2) score >4
• Having absolute contraindications to exercise and to undergo transcranial magnetic stimulation (TMS);
• Currently are or will be enrolled in a drug or exercise trial during the duration of the study;
• Having participated in a structured exercise program > 2 times per week in the two months prior to the enrollment in the study

Results will be published in peer-review journals.