Iterative Adaptations in a Physical Activity Program for Children with Autism: A Feasibility and Implementation Study

Background: Children and adolescents with autism spectrum disorder (ASD) are generally more sedentary and engage less in physical activity (PA) than their peers. Despite increasing evidence of benefits, practical guidance on implementing adapted PA programs in real-world settings remains limited. This study aimed to document iterative adaptations, implementation processes, and participant experiences in a structured PA intervention for children with ASD. Methods: Nineteen children aged 10-14 years with ASD participated in an adapted PA intervention delivered across three cohorts. The program was progressively modified based on observed barriers and participant feedback. Post-intervention conversations with participants and/or parents were used to assess feasibility and experiences. Results: Most participants trained on-site in small groups and were predominantly boys, many with comorbid ADHD/ADD. Baseline engagement in organized PA was low. Adaptations included adjustments to session structure, group size, instructor-to-participant ratio, and activity content to enhance predictability and autonomy. Individual tailoring and flexible delivery were essential to accommodate neurodevelopmental diversity and fluctuating motivation. Post-intervention feedback suggested generally positive acceptability, while findings should be interpreted descriptively. Conclusions: This study provides preliminary, practice-based insights into how structured PA programs may be iteratively adapted for children with ASD in a supportive clinical context. The findings highlight practical considerations for implementing adapted PA in clinical and community settings.