INTRODUCTION
Physical activity, mental health, and nutrition are critical components of overall health and well-being, particularly in children and adolescents. The World Health Organization (WHO) emphasizes the importance of these three factors in promoting good health and preventing chronic diseases later in life. However, despite the well-established benefits of physical activity, healthy eating, and positive mental health, many children and adolescents fail to meet recommended guidelines in these areas.
Regular physical activity helps children and adolescents develop strong bones, muscles, and cardiovascular systems, improves overall physical health, and reduces the risk of chronic diseases such as obesity, diabetes, and heart disease,. In addition to its physical benefits, physical activity has been linked to better mental health outcomes, including reduced symptoms of depression and anxiety, improved self-esteem, and enhanced academic performance,.
Healthy eating habits are also essential for promoting overall health and well-being in children and adolescents. Proper nutrition supports body and brain development and can reduce the risk of chronic diseases later in life. However, many children and adolescents consume diets high in unhealthy fats, sugars, and processed foods while lacking nutrient-rich foods such as fruits, vegetables, and whole grains.
Mental health is equally important for overall well-being. Poor mental health can negatively affect physical health, academic performance, and social relationships. Mental health issues, such as anxiety and depression, are common among children and adolescents and can be exacerbated by factors such as stress, lack of physical activity, and poor nutrition,.
In summary, physical activity, healthy eating, and positive mental health are crucial for the overall health and well-being of children and adolescents. Encouraging these behaviours early in life can provide long-term benefits for physical and mental health and help reduce the risk of chronic diseases later in life.
Therefore, the primary objectives of this project are to characterize youth lifestyle behaviours and analyze the interactions among healthy and unhealthy lifestyle factors. As a secondary objective, the project aims to develop and provide a comprehensive suite of digital tools for young people, parents, and teachers to facilitate easier access to a healthy lifestyle.
METHODS
Participants and selection criteria
The present cross-sectional project involves study research conducted in the partner countries participating in the RYHEALTH project consortium (https://ryhealth.net/), namely Spain, Portugal, Germany, and Sweden. RYHEALTH aims to increase the impact of European actions for health promotion and disease prevention, focusing on health-enhancing physical activity, a healthy environment, healthy eating, and mental health and well-being among young individuals.
Eligible participants are youth from European countries. Inclusion criteria include: i) being between 10 and 17.9 years old, ii) having parental or guardian consent to participate in the questionnaire, and iii) having sufficient comprehension of one of the available languages for the questionnaire (i.e., German, Spanish, Portuguese, Swedish, or English). Participants who do not meet these criteria will be excluded from the study.
Data Collection
To gain insight into the lifestyles of children and adolescents and their perspectives on health-related behaviors, the RYHEALTH consortium has established four fundamental pillars, which correspond to subprojects: The Happiness Project, The Activity Project, and The Food Project. These pillars guide the measurements, focusing on three evaluation blocks: i) sociodemographic aspects, ii) mental health, and iii) lifestyle behaviors. Participants will complete a multidisciplinary, digital, and online questionnaire called the "RYHEALTH e-Questionnaire" (https://hub.ryhealth.net/survey). The questionnaire has been developed in English and subsequently translated into German, Spanish, Portuguese, and Swedish. It will be available online through the RYHEALTH platform. To engage the target group and collect data anonymously, the RYHEALTH consortium employs various strategies. These include dissemination through the social media channels of the project and its partners, outreach to traditional media outlets, and direct contact with educational centers to promote participation among students. Additionally, project staff distribute the questionnaire directly at RYHEALTH and externally organized events.
Outcomes measures
The RYHEALTH e-Questionnaire includes participants' history along with validated questionnaires focusing on the main 4 subprojects of a healthy lifestyle promoted by the project. Therefore, the final RYHEALTH e-Questionnaire consists of 4 sections; the first includes questions on anthropometric, sociodemographic information, and relevant covariates such as socioeconomic level. The remaining 3 sections are based on behavioral and lifestyle factors related to 3 RYHEALTH subprojects:
Section 1: RYHEALTH-specific section
This section comprises information on sociodemographic aspects, socioeconomic status, as well as self-reported anthropometric information such as height and weight. Precisely, The Family Affluence Scale (FAS) will measure the socioeconomic level of families. The FAS consists of four items that ask about the family's material possessions and experiences, such as owning a car, having their own bedroom, going on vacations, and the number of computers. The children are asked to indicate whether each item applies to their family. The responses are then combined to create a composite score that provides an estimate of the family's level of material affluence. The FAS has shown a high internal consistency, good test-retest reliability, and validity.
Section 2: Mental health – The happiness project
Stress will be evaluated by The Perceived Stress Scale (PeSS), a widely used questionnaire designed to measure the degree to which individuals perceive their lives as stressful. The PeSS consists of 10 items, each asking about feelings and thoughts related to stress in the past month. Participants rate each item on a 5-point scale ranging from 0 (never) to 4 (very often). Examples of items on the PeSS include "In the last month, how often have you felt that you were unable to control the important things in your life?" and "In the last month, how often have you felt nervous and 'stressed'?". The PeSS has been used to assess stress in a wide range of populations, including college students, medical patients, and community samples. It has also been translated into many languages and has been used in cross-cultural research. The PeSS has shown a high internal consistency, good test-retest reliability, and validity.
Health-related quality of life (HRQoL) will be assessed by the KIDSCREEN-27, a self-reported questionnaire applied in children and adolescents aged 8-18 years old. The KIDSCREEN-27 consists of 27 items that are grouped into five dimensions: physical well-being, psychological well-being, autonomy and parent relations, social support and peers, and school environment. Each item is scored on a 5-point Likert scale. The KIDSCREEN-27 has shown high internal consistency, good test-retest reliability, and validity.
Section 3. Lifestyle behaviours – The activity and food projects
In this section, physical activity, self-reported physical fitness, sedentary behaviour, sleep, eating behaviour and adherence to the Mediterranean diet will be assessed by using the following questionnaires, respectively.
The International Physical Activity Questionnaire (IPAQ) for Children and Adolescents is a questionnaire designed to assess physical activity levels in young people aged 5-17 years. The IPAQ for Children and Adolescents consists of seven items that ask about the amount of time spent doing different types of physical activity, such as walking, running, cycling, and playing sports, over the past seven days. Participants are asked to indicate the frequency, duration, and intensity of each type of physical activity they engaged in during the past week. The IPAQ has shown a high internal consistency, good test-retest reliability, and validity.
The International Fitness Scale (IFIS) is a self-reported questionnaire designed to measure physical fitness (cardiorespiratory fitness, muscular strength, speed-agility, and flexibility) in children and adolescents. The IFIS consists of 5 items asking about how the participant thinks that is his/her physical fitness level compared to their friends. Each item is scored on a 5-point Likert scale. The IFIS has shown good test-retest reliability and validity.
The Youth Leisure-time Sedentary Behavior Questionnaire (YLSBQ) is a self-report questionnaire designed to assess sedentary behavior in children and adolescents aged 10-18 years. The YLSBQ consists of 12 items that ask about the amount of time spent engaged in different sedentary behaviors, such as watching TV, playing video games, and using the computer, during leisure time on a typical weekday and weekend day. Participants will be asked to indicate the amount of time they spend engaged in each activity in hours and minutes. The YLSBQ has shown a high internal consistency, good test-retest reliability, and validity.
Sleep quantity will be measured by asking the wake-up and fall asleep either for weekdays and weekends. In addition, we will measure sleep quality by the Epworth Sleepiness Scale (ESS) for children and adolescents is a self-report questionnaire designed to assess daytime sleepiness in children and adolescents aged 6-18 years. The ESS for children and adolescents consists of eight items that ask about the likelihood of falling asleep during different activities, such as sitting and reading, watching TV, and sitting and riding in a car, on a scale of 0-3. The ESS has shown a high internal consistency, good test-retest reliability, and validity.
The 21-item Three-Factor Eating Questionnaire (TFEQ-R21) is a self-report questionnaire designed to assess three factors related to eating behavior: cognitive restraint, disinhibition, and hunger. The TFEQ-R21 is a modified version of the original TFEQ, which consisted of 51 items. The TFEQ-R21 consists of 21 items that ask about various aspects of eating behavior, such as how often the participant thinks about food, how much they enjoy eating, and how often they eat when feeling anxious or stressed. The TFEQ-R21 has shown a high internal consistency, good test-retest reliability, and validity.
The KIDMED questionnaire is a tool that was developed to assess the quality of the Mediterranean diet in children and adolescents aged 2-24 years old. The KIDMED questionnaire consists of 16 items that assess various aspects of the Mediterranean diet, such as the consumption of fruits, vegetables, fish, nuts, and olive oil, as well as the intake of foods that are high in sugar and saturated fat. Each item is assigned a score of +1 or -1 based on the “yes” or “no” responses. The KIDMED has shown a high internal consistency, good test-retest reliability, and validity. The estimate duration will be 2 minutes.
Sample size
It is expected to obtain a minimum of 200 and up to 500 completed questionnaires from each of the four countries, which makes a total of expected responses ranging from 800 to 2,000. This estimation will provide a comprehensive understanding of children and adolescents that accurately reflects the general population and their characteristics. It will enable statistical analysis of cohorts, including potential sensitivity analyses based on factors such as age, gender, demographics, lifestyle behaviors, mental health outcomes, or any other unique group relevant to research interest.
Digital HUB for Youth
The RYHEALTH project aims to create and deliver a comprehensive set of digital tools for parents, teachers, and students to facilitate access to a healthy lifestyle and promote a network among them, called the "RYHEALTH HUB". This platform will host resources based on updated scientific evidence, adapted for easy understanding and applicability. It will include learning and empowerment tools in each of the four RYHEALTH subprojects: Activity (Physical Activity), Food (Healthy Eating), Happiness (Mental Well-being), and Sustainability.
The HUB will feature various tools such as podcasts, videos, infographics, interactive guides, online challenges, games on healthy lifestyles on interactive platforms, and resources for educational sessions, among others.
Ethical considerations
All participants will require parental or guardian consent, provided by confirming online, to allow the data collected in the questionnaire to be used for research purposes within the framework of the European RYHEALTH project. Parents or guardians will be informed that the data are completely anonymous, do not personally identify their children, and will only be used for the purposes established in the research project. They will also confirm their understanding that the questionnaire complies with the General Data Protection Regulation (GDPR) for the processing of personal data in the European Union, published on 17 April 2016, repealing the former Directive 95/46/EC.
Statistical analyses
Descriptive analyses will be performed for continuous and categorical variables. The mean, standard deviation, minimum, maximum and quartiles or percentages will be calculated for continuous and categorical variables, respectively. Covariates will be identified through examining associations between specific questions in each questionnaire and demographic or other variables. Multiple linear regression analyses will be used to examine the association of Linear regression models, logistic regression, and ANCOVA will be conducted to study the associations and interactions between the variables across different dimensions, with a particular focus on analyzing the relationship between healthy and unhealthy patterns and characteristics. All analyses will be performed using the STATA software for Windows version 14.0. The level of significance was set at p<0.05 in the statistical model.
EXPECTED RESULTS
The RYHEALTH project is expected to provide a comprehensive understanding of the lifestyle behaviors of European youth aged 10-17.9, offering valuable insights into the interconnections between physical activity, nutrition, mental well-being, and environmental factors.
First, we anticipate that a substantial proportion of participants will probably fail to meet the recommended guidelines for physical activity, dietary habits, and mental health, aligning with previous literature indicating low adherence to health-promoting behaviors in adolescents. Furthermore, significant differences may emerge based on sociodemographic factors such as age, gender, and socioeconomic status, providing an opportunity to identify high-risk subgroups requiring targeted interventions.
Regarding physical activity, we expect to observe an association between higher levels of engagement in structured and unstructured exercise with improved self-perceived fitness, better mental health outcomes, and/or lower sedentary time. Conversely, excessive screen time and sedentary behavior are likely to correlate with poorer self-rated health, lower adherence to a balanced diet, and higher levels of stress and anxiety.
For nutrition, it is hypothesized that a considerable percentage of adolescents will demonstrate suboptimal adherence to a Mediterranean diet, with a higher prevalence of processed food consumption and low fruit and vegetable intake. This dietary pattern may be negatively associated with mental well-being indicators such as stress levels and self-reported health status.
In the mental health domain, we anticipate that higher engagement in physical activity, better sleep quality, and frequent exposure to nature will be protective factors against anxiety and depressive symptoms. Additionally, perceived stress is expected to be inversely correlated with quality of life and overall well-being, reinforcing the importance of integrated health promotion strategies.
Finally, the RYHEALTH HUB, the digital intervention platform, is expected to enhance accessibility to evidence-based health education resources for adolescents, parents, and educators, ultimately facilitating behavior change and long-term adherence to a healthier lifestyle. The project outcomes will contribute to developing innovative policies and interventions aimed at improving adolescent health across multiple European contexts.
FUNDING INFORMATION
This work is funded by the European Commission Project – EU4Health "RYHEALTH" – Project ID: 101079938. The research work done by DJP is supported by the Biomedical Research Networking Center on Frailty and Healthy Aging (CIBERFES) and FEDER funds from the European Union (CB16/10/00477). The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding institutions.
ACKNOWLEDGEMENTS
The authors would like to thank all the organizations, educational centers, and media outlets that are actively collaborating in the dissemination of the RYHEALTH Project to reach the target population.
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