The goal of this interventional, quasi-experimental study is to evaluate whether a digital dual-task exercise and behavioral program can improve physical activity and influence patient-reported outcomes in people with Parkinson's disease.

The main questions it aims to answer are:

1. Is the MOVE ON UP digital intervention feasible and acceptable, based on recruitment, retention, adherence, and safety?
2. Does participation in the program lead to increased physical activity levels?
3. Does the intervention produce exploratory improvements in patient-reported outcomes such as motor symptoms, balance confidence, and quality of life?

Because the study includes a comparison group, researchers will compare participants receiving the MOVE ON UP digital intervention with participants receiving usual care to determine whether the digital program produces measurable behavioral and functional changes.

Participants will:

1. Complete baseline and post-intervention assessments of physical activity and patient-reported outcomes.

2. Engage in an 8-week digital dual-task exercise program, including:

   2.1 Structured dual-task exercise sessions delivered digitally. 2.2 Educational content related to Parkinson's disease and physical activity. 2.3 Behavioral support elements informed by the COM-B model.

3. Use the digital platform to follow the program and complete follow-up questionnaires.

This study employs a quasi-experimental, multicenter, two-arm design to evaluate the feasibility, acceptability, and preliminary efficacy of the MOVE ON UP digital exercise program as a complement to usual care. The study will be conducted across four European countries: Portugal, Greece, Croatia, and Italy, involving partner organizations Egas Moniz School of Health & Science (EM, Portugal), Young Parkies Portugal (YP, Portugal), Aristotle University of Thessaloniki (AUT, Greece), Omišalj-Njivice Gymnastics Club (GON, Croatia), and Università degli Studi "G. d'Annunzio" Chieti-Pescara (UdA, Italy).

All participants will continue their usual medical care and ongoing activities throughout the study period. The intervention group will receive the 8-week digital exercise program in addition to usual care. A non-randomized comparison group will receive usual care alone. This design allows preliminary comparison of outcomes between those receiving the digital program and those continuing with standard care, while maintaining feasibility across sites.

The primary outcomes are feasibility (recruitment, retention, adherence, safety) and change in physical activity levels (primary behavioral outcome). Secondary outcomes include patient-reported changes in motor symptoms, balance confidence, quality of life, and psychological determinants. Randomization was not deemed appropriate at this stage given the primary objective of evaluating a newly developed digital program and the logistical constraints of a four-country multicenter design. The study will be reported in accordance with the Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) statement guidelines.

The study comprises three distinct phases spanning approximately 14 weeks per participant: 1) screening and baseline assessment (Week 0), 2) 8-week intervention period (Weeks 1-8), and 3) post-intervention assessment (Week 9).

Screening and Enrolment (Week 0): Potential participants expressing interest through partner organization outreach, stakeholder networks, and social media campaigns will be directed to the MOVE ON UP study website. After registering and providing initial electronic consent, candidates will complete an online screening questionnaire to assess eligibility. Eligible individuals will receive detailed study information and informed consent will be obtained electronically prior to any study procedures.

1. Baseline Assessment (Week 0): All enrolled participants will complete a comprehensive baseline assessment battery. All participants, regardless of group, will receive login credentials to access the study website and complete the following assessments at baseline and post-intervention: (1) primary outcome-physical activity levels measured by the International Physical Activity Questionnaire (IPAQ); (2) secondary outcomes-balance (Falls Efficacy Scale International [FES-I]), quality of life (Parkinson's Disease Questionnaire-8 [PDQ-8]) , and psychological determinants (Exercise Self-Efficacy Scale [ESES], COM-B Self-Evaluation Questionnaire) ; (3) demographic and clinical information including age, sex, disease duration, Hoehn and Yahr stage, current medications, and exercise history.
2. Intervention Period (Weeks 1-8): Following completion of baseline assessments, participants in the intervention group will receive access to the MOVE ON UP digital exercise program via the same platform. The intervention consists of three components: (1) 6 educational lectures (45-60 minutes each) covering topics relevant to exercise and PD; (2) three weekly 60-minute pre-recorded exercise sessions for 8 weeks (24 sessions total) , each combining physical exercises with embedded cognitive challenges requiring both movement and vocal responses; and (3) automated theory-driven text messages targeting COM-B components (capability, opportunity, motivation), delivered in weekly blocks with content tailored to the adoption, maintenance, and consolidation phases of behavior change. Participants are encouraged to complete sessions at consistent times and utilize the website's progress tracking features. Automated reminders are sent if no activity is detected for 72 hours. A support system will allow participants to submit questions to regional staff, with responses provided within 48 hours. Discussion forums enable asynchronous peer interaction.
3. Post-Intervention Assessment (Week 9): Within one week of completing the 8-week program, all participants will complete the full assessment battery again, following identical procedures to baseline. Additionally, all participants will complete a program satisfaction questionnaire assessing ease of understanding, ease of operationalizing instructions, content appropriateness, content relevance, content innovation, program length, and likelihood of recommending the program to a friend, rated on 5-point Likert scales.

STUDY SETTINGS The study is conducted entirely in community settings across four countries from January to July 2027. The intervention is delivered remotely via the MOVE ON UP MOOC, available at https://moveonup.csd.auth.gr (the platform is accessible at https://moveonup.csd.auth.gr/mooc/), from participants' homes using personal computers, tablets, or smartphones with internet connection. Telephone and email support is available if technical difficulties arise.

Inclusion Criteria:

• Diagnosis of idiopathic Parkinson's disease (self-reported; verification requested from treating physician or neurologist when possible)
• Hoehn and Yahr stages I-IV (mild to moderate disease severity; ambulatory with or without assistance)
• Age 18 years or older
• Access to a computer, tablet, or smartphone with reliable internet connection
• Basic digital literacy to navigate the study website (caregiver assistance permitted if needed)
• Ability to communicate with study personnel in the local language (Portuguese, Greek, Croatian, or Italian) to understand instructions and provide informed consent
• Willingness and ability to provide written informed consent electronically prior to enrolment
• For those completing remote assessments, willingness to complete self-assessments with or without caregiver assistance following provided video instructions

Exclusion Criteria:

• Self-reported severe cognitive impairment that would preclude understanding and following exercise instructions, based on clinical judgment of referring provider or study coordinator following screening conversation
• Significant active psychiatric problems (e.g., untreated major depression, psychosis, substance abuse) that would interfere with participation or adherence
• Medical conditions contraindicating moderate-intensity exercise, including:

Unstable cardiovascular disease (uncontrolled hypertension, recent myocardial infarction, unstable angina) Severe orthopedic limitations (acute fractures, severe osteoarthritis limiting mobility) Other systemic conditions that would make participation unsafe as determined by the participant's physician or study coordinator during screening

• Pregnancy
• Anticipated inability to complete the 8-week intervention period due to planned surgery, extended travel, or other commitments

Participants with a caregiver willing to assist with technology, assessments, or exercise supervision are not excluded; caregiver involvement will be documented and considered in exploratory analyses where appropriate.

Data obtained in this study may be provided to qualified researchers with academic interest in digital exercise for people with parkinson's. Data or samples shared will be coded, with no PHI included. Approval of the request and execution of all applicable agreements (i.e. a material transfer agreement) are prerequisites to the sharing of data with the requesting party.

Data requests can be submitted starting 9 months after article publication and the data will be made accessible for up to 24 months. Extensions will be considered on a case-by-case basis.

Access to trial IPD can be requested by qualified researchers engaging in independent scientific research and will be provided following review and approval of a research proposal and Statistical Analysis Plan (SAP) and execution of a Data Sharing Agreement (DSA). For more information or to submit a request, please contact xmelo@egasmoniz.edu.pt