The goal of this clinical trial is to learn if watching instructions for daily exercises with three different contents (the patients themselves, other children, or children dressed as rabbits in addition to their physiotherapist, could increase physical activity among children with autism.

The main questions it aims to answer are: Are children with autism motivated to engage in daily exercise by seeing themselves in a mobile application? Researchers will compare instructions with the children themselves with instructions containing other children and children in rabbit suits.

Parents and their children will use the mobile application once daily for 8 weeks, and 5-10 minutes per day.

Parents will fill out questionnaires before, during and after the 8-week intervention, and write about their experiences in the mobile application 2-3 days per week.

BACKGROUND Autism is a collective term for a heterogeneous group of neurological disabilities that mainly manifest themselves in the form of persistent difficulties in social interaction and rigid or repetitive patterns of behavior, activities and interests. The cause of autism is multifactorial and research has shown that there is a complex interaction between genetics and environmental factors when a problem of clinical dimensions is established. Approximately 1 in 50 children is diagnosed with autism, and the problems usually make themselves known at an early age. Autism can often be diagnosed at the age of 2-3 years, although some are diagnosed much later. In many parts of the world, the prevalence of autism has increased, but this is probably due to increased awareness and changes in diagnostic criteria rather than a real increase in incidence.

Children with autism also have a greater degree of intellectual disability, ADHD, anxiety, and epilepsy, which can sometimes complicate both diagnosis and treatment. The great variation in how autism is expressed requires individual strategies in treatment. Over the past decade, research has demonstrated the central role of physical activity in the development of psychological functioning and well-being in children and adolescents in general. Knowledge about how physical activity can improve social, cognitive, and behavioral outcomes in children and adolescents with autism is lacking, and in particular, we know significantly less about young children compared to slightly older children and adolescents.

In two recently published meta-analyses on the importance of physical activity for children with autism, Hassan et al. (2023) and Hynes et al. (2023) highlight group-based exercise as particularly beneficial, but very few studies have examined children in younger age groups. The studies that do exist have generated preliminary evidence for positive effects on attention, memory, problem-solving, and cognitive skills that are linked to motor function. In a 2014 study, Sorensen et al. reported reduced incidence of outbursts and disruptive behavior after physical activity interventions. Similar results were also reported by Liu et al., who noted improved emotion regulation. The link to improved emotion regulation could be a contributing factor to the fact that physical fitness is negatively associated with the risk of developing anxiety and depression.

Despite emerging scientific understanding of the importance of physical exercise for children with autism, there are several important knowledge gaps. Most previous studies have mixed children of different ages, which means that we know little about physical activity in young children with autism. The few studies conducted in young children with autism have not evaluated clearly defined interventions that could be applicable as clinical treatment programs. A prospective study of 100 Swiss children, who were followed from preschool age to grade 2, demonstrated that structured physical activity had a clear positive effect on motor development, while unstructured physical activity lacked such an effect.

A clinically important knowledge gap is the importance of parents for children's activity levels and questions related to how the family can be involved in structured interventions. This aspect is important as physical activity can only lead to positive long-term effects if it is sustained even after a period of supervised training in a clinic. Young children who have just been diagnosed with autism may find it difficult to thrive in the group context that gymnastics, dance, and early introduction to various sports involve. In other words, motivational aspects and evidence-based methods to overcome obstacles to daily movement are as important to study as effects on symptoms, problem behaviors, and motor and cognitive development.

PURPOSE The STAMP study addresses several of these knowledge gaps by studying an individually adapted intervention for parent-guided physical activity at home, and by studying different ways to motivate children to engage in daily physical activity. More specifically, the STAMP study aims to determine whether children with autism are motivated by seeing themselves together with a physiotherapist in a newly developed mobile application and whether it is feasible to have parents lead a structured daily movement game for 8 weeks with digital support from an experienced physiotherapist.

VISION & OBJECTIVES The long-term vision of the project is to develop and evaluate a way to prescribe parent-guided daily physical activity to children with different types of neuropsychiatric problems at different ages. The first sub-study (STAMP) aims to test the feasibility of newly developed technology and evaluate whether parents, with the support of the technology and healthcare professionals, can take responsibility for making the daily exercise happen. In summary, the goal of the STAMP study is to study aspects of motivation in both parents and children, thus to map the feasibility of the newly developed e-health intervention.

RESEARCH QUESTION Are children with autism motivated to engage in physical activity by seeing themselves and their physiotherapist in a mobile application with parent-led training at home?

HYPOTHESES

• Seeing oneself is more fun than seeing other children, and as fun as seeing rabbits
• Seeing oneself and the physiotherapist becomes more interesting over time
• Training sessions that are perceived as interesting and completed reduce the risk of skipping sessions the next day

RECRUITMENT OF STUDY PARTICIPANTS The study will be conducted at the Children and Youth Rehabilitation Center in Linköping with the help of a physiotherapist who works with children with autism. The study is limited to children with a diagnosis of autism and an age < 10 years. It does not matter if the diagnosis is new or has existed for some time. It also does not matter if the child has multiple diagnoses (e.g., ADHD, Lindrig IF, epilepsy). For practical reasons, the study is limited to children with autism who have seen, or are going to see, a physiotherapist, due to, for example, toe walking, motor difficulties, or coordination difficulties.

STUDY DESIGN STAMP is an open intervention study with a repeated cross-over design

Population size In order to both generate answers to the study's research question and at the same time respect the limits of what is reasonable in a feasibility study, the research team will apply a sequential monitoring of the study's primary outcome measure using Bayesian probability calculation. With this method, the risk of both over- and under-recruitment can be minimized.

PROJECT PLAN Fall 2024: Development of Jr functions in the Phystic mobile app, recording of instructional videos.

Spring 2025: EPM application, refining technology, and questionnaire. Fall 2025: Prepare recruitment of study participants and data collection. Spring 2026: Start of recruitment and data collection (monitoring of preliminary results) Fall 2026: Continued recruitment and data collection (monitoring of preliminary results) Spring 2027: Continued recruitment and data collection (monitoring of preliminary results) Fall 2027: Completion of data collection, analysis of results, and compilation. Spring 2028: Reporting of the study's findings in a scientific publication, etc.

DATA MANAGEMENT Questionnaires that are collected will be continuously coded (calculation of total score). The responses will be anonymized and transferred to a data file that is stored on a secure server at LiU. Data from the mobile app will be stored on the user's own device during the study period and sent encrypted and password-protected to a research computer at LiU. When study participants end their participation, their data (recorded films, measurements of time to loss of interest, and responses to questions) will be automatically deleted from their devices.

DATA ANALYSIS Collected research data will be analyzed using parametric or non-parametric hypothesis testing methods, depending on whether they are found to be normally distributed or not. Descriptive statistics will be used to analyze means and variability in measurements (both between and within individual participants).

For the primary outcome measure, time to loss of interest for the three films, the data will consist of repeated measurements and a continuous dependent variable (seconds), and we will want to analyze both the effect of each film and the random variation between different participants. This means that we plan to use a so-called linear mixed-effect model (LME), or linear model with random effects. Trends and change over time, i.e., which of the three became less or more interesting, will be analyzed with time series. The relationship between the type of session (categorical data) and the risk of declining motivation (skipped session, a binary outcome variable) the next day will be analyzed with logistic regression.

The secondary outcome measures (exercise enjoyment, sleep, anxiety, and life satisfaction in parents) will be evaluated with descriptive statistics and simple comparisons of means (t-test or Wilcoxon rank sum test). The parents' answers to the open-ended questions about their experiences of leading the home training for 8 weeks will be analyzed systematically with qualitative content analysis [17]. Complementary analyses with Bayesian statistics will be used to calculate the probability that any type of film resulted in increased motivation to complete the training sessions.

ETHICAL ASPECTS Previous research has shown that structured physical activity helps preschool children develop motor skills in a safe way. Physical activity is never completely risk-free, but the training sessions in the mobile app are instructed by a physiotherapist with experience in instructing children with autism, and using the mobile app is considered to pose a lower risk of injury than many everyday situations, such as gymnastics at preschool/school or free play outdoors. All handling of personal data will be carried out in accordance with the rules of the GDPR. The mobile application stores information about user statistics and the registrations that parents make in connection with the training sessions and weekly answers to open-ended questions. In connection with the collection, the data will be anonymized. The study involves a total of about 1-2 hours for filming and data collection that goes beyond regular care. The time spent on the training that the parents are expected to carry out at home using the mobile app is the same as they would have been prescribed via an information sheet if they had not chosen to participate in the study. Families are allowed to borrow exercise equipment during the study period that is not part of regular care. Overall, the benefits of participating in the project are judged to far outweigh the risks.

CLINICAL SIGNIFICANCE Knowledge of the importance of physical exercise for the development of motor, cognitive, and emotional skills in children with neuropsychiatric disabilities has increased in recent decades. Despite our knowledge of the possibilities of stimulating positive development through specific exercise and physical activity, far from all children with autism are offered early contact with a physiotherapist. Those who are offered contact receive a limited intervention that usually includes written advice on activities and everyday play that challenge the child's motor skills and one or two follow-up visits. The STAMP study will contribute new knowledge about how new technology and new approaches can support parents to maintain daily specific physical activity. The approach in the STAMP study is based on a combination of pedagogical principles and the alliance that arises in the relationship with the family's physiotherapist, who prescribes the exercise program. In summary, positive results from the study could lead to the implementation of further developed versions of both technology and intervention in the care of children with neuropsychiatric problems and, in the long run, lead to more children being able to have better conditions for positive development.

RESEARCH GROUP Oskar Lundgren* (Project Leader, Senior Physician in the teams for child neurology and neurorehabilitation US Lkpg) Emma Egelstig (Child Physiotherapist, HAB) Ellinor Nilsson (Physiotherapist, R&D Manager HAB, PhD student in the subject of training for young people with IF) Rodica Schwarts (ST doctor in Child and Adolescent Neurology and Habilitation) Benjamin Lassebo (Psychologist, PhD student in the subject of psychological interventions for children with autism)

Inclusion Criteria:

• Access to a mobile phone or tablet with a camera and internet at home.
• Autism diagnosis in the child in question (the patient).
• Someone in the family knows enough Swedish to understand the information about the study and the content of the mobile app.

Exclusion Criteria:

• Medical impediment to training with the parents and performing the exercises in the prescribed training sessions.
• Age >10 years.