IDHEApp will implement various educational technology tools and work with the families, teachers and caregivers to increase physical activity (PA) and improve healthy eating. Due to the current COVID-19 pandemic restrictions, the use of innovative digital technology can contribute not just to distance learning but also to support families and students in remote. However, both healthy habits and technologies are insufficiently addressed in the population with IDD. These needs are in line with the following objectives of the Erasmus+ programme: a) Inclusion and diversity in all fields of education, training, youth and sport; b) Addressing digital transformation through development of digital readiness, resilience and capacity, and c) Encouraging the participation in sport and physical activity.

Educators will find innovative possibilities and the right instruments that will enable them to fulfil their potential through innovative online education & learning & training skills module for lifestyle promotion and others available on the app. Furthermore, mentors and others health professionals (e.g., nursing etc.) will be equipped with knowledge and skills on how to use the app to teach practical skills for PA enhancement in an evidence-based way. Consequently, this project will contribute to [specific objectives - SO]:

- Raise awareness of the importance of healthy and active living among young Europeans with intellectual disabilities.

Different workshops and bigger events (i.e., international conference), together with the involvement of numerous participants from the institutions of this consortium will be ensured. Further, a sensitized community will participate through the social networks and the website itself, in the proposed activities.

- Provide digital resources and tools to the partner entities of the exchange to improve lifestyle of young people with intellectual disabilities.

Best Practices to provide high quality, inclusive digital health education with the best educational technology tools and methodology. A website, a mobile app and different electronic guidelines will be delivered.

- Analyze the current state of use and acceptance of technologies as support in the management of health in adolescent with intellectual disabilities.

Young individuals with intellectual disabilities (ID) often exhibit significant challenges in maintaining healthy lifestyle habits, particularly concerning physical activity and nutrition. Current evidence indicates that individuals with ID participate in significantly lower levels of physical activity compared to their typically developing peers, with a substantial proportion not meeting established physical activity guidelines. A recent literature review highlights that adults with ID often exhibit elevated levels of sedentary behaviour, which is associated with increased prevalence of obesity, multimorbidity, and metabolic syndrome. The review emphasizes that sedentary behaviour may contribute to the poor health commonly observed in this population. In addition to insufficient physical activity, dietary patterns among young people with intellectual disabilities often skew towards processed foods high in sugar and fat, further compounding their overall health risks.

Addressing these unhealthy behaviors is critical, as they significantly impact the overall well-being of young individuals with ID. Various strategies have been developed to manage and improve lifestyle-related health outcomes in this population. Interventions focusing on lifestyle modifications commonly emphasize structured exercise programs and nutritional education, aiming to promote sustainable, positive health behaviors. However, traditional intervention approaches often face significant challenges in effectively engaging young people with ID, limiting their long-term impact.

In recent years, mobile health (mHealth) interventions have emerged as innovative tools that leverage technology to enhance physical activity and nutritional habits among young individuals with ID. These digital solutions have demonstrated efficacy in promoting behaviour change through interactive, user-friendly platforms, offering an especially attractive alternative for populations that often encounter barriers in traditional health intervention contexts. Existing studies indicate that mHealth applications can facilitate behaviour modification by providing tailored feedback, goal-setting functionalities, and motivational elements, such as gamification.

Despite the significant promise of mHealth interventions in promoting healthier behaviors, evidence regarding their efficacy specifically among individuals with ID remains scarce. Most existing studies have focused on the general population, with limited research adapting these technologies to the cognitive, social, and communication needs of individuals with ID. Several barriers may limit the effectiveness and scalability of mHealth solutions in this population, including difficulties with digital literacy, limited accessibility features in current applications, lack of caregiver or support system involvement, and challenges related to sustained engagement over time. Consequently, there is a critical need for rigorously designed studies that not only evaluate the effectiveness of mHealth interventions for young individuals with ID, but also systematically address the unique barriers this population faces in accessing and benefiting from such technological innovations. Additionally, a significant gap persists in research that adequately considers the diverse manifestations of intellectual disability (e.g., such as Down syndrome and other neurodevelopmental conditions), leading to an incomplete understanding of the true potential and limitations of mHealth solutions across the full spectrum of cognitive and functional profiles. To date, there are only a limited number of studies specifically exploring the use of mHealth interventions to promote physical activity among individuals with ID. Various initiatives demonstrate the feasibility of integrating digital tools to promote physical activity among individuals with ID, they also present notable limitations. These include small sample sizes and a focus on specific subgroups, which hinder the generalizability of their findings. Furthermore, many of these studies predominantly involved adult participants, leaving a significant gap in research related to younger populations, where early intervention is crucial for fostering long-term healthy behaviors. In response to these gaps, our study aims to conduct a randomized controlled trial (RCT) to assess the effectiveness of mHealth interventions in improving physical activity and nutrition in young individuals with ID. By addressing the unique barriers this population faces in engaging with digital health solutions, our research seeks to provide a more comprehensive and inclusive understanding of how mHealth interventions can positively impact health outcomes during this critical developmental stage. Through this approach, we aim to identify effective strategies for promoting sustainable behavior change in young individuals with ID.

Methods Study Design This study followed a multicenter, randomized controlled trial (RCT) design and was conducted in two European cities: Rome (Italy) and Rijeka (Croatia). Participants were stratified by site and randomly assigned to either an experimental group, which received a gamified mHealth-based intervention aimed at improving physical activity and eating habits, or to a control group, which continued with their usual routines without intervention. In Rome, the sample included only individuals with Down syndrome, while in Rijeka the participants had mild to moderate intellectual disabilities without comorbid Down syndrome. Randomization was carried out using a computer-generated sequence, and the allocation was concealed until the moment of assignment. All procedures complied with the ethical standards of the institutional research committees and adhered to the Helsinki Declaration. Informed consent was obtained from participants or their legal representatives.

Inclusion Criteria:

• Diagnosis of intellectual disability
• Being able to follow basic instructions
• Age between 4-30 years old

Exclusion Criteria:

• presence of severe sensory or motor impairments
• medical conditions that contraindicated moderate physical activity
• unable to access an smartphone during the intervention

Individual Participant Data (IPD) that will be shared include de-identified data related to primary and secondary outcomes, such as measures of physical activity (e.g., step counts, activity duration), sleep duration, and nutrition-related behaviors. Only IPD used in the results publication will be shared. No personally identifiable information will be included. Data will be shared in accordance with applicable ethical approvals and data protection regulations. Due to the vulnerability of the study population, access to the IPD will be limited to qualified researchers upon reasonable request and subject to a data sharing agreement that ensures confidentiality and appropriate data use.

De-identified individual participant data (IPD) will be made available beginning 6 months after publication of the primary results and will remain available for a period of 5 years following publication.

Access to the de-identified individual participant data (IPD) will be granted to qualified researchers affiliated with academic or non-profit institutions for the purpose of secondary analyses related to intellectual disabilities, mHealth interventions, or health promotion. Requests must include a detailed research proposal, ethical approval or exemption, and a signed data use agreement. All requests will be reviewed by the study steering committee to ensure appropriate use and compliance with data protection regulations.

Due to the nature of the behavioral mHealth intervention, participants and intervention facilitators could not be blinded to group allocation. However, outcome assessors and data analysts were masked to group assignments to minimize potential bias in data collection and analysis. Additionally, caregivers and teachers involved in routine support were not informed of specific hypotheses or group distinctions to reduce influence on participant behavior.