Effects of Adapted Aquatic Exercise on Autism-Related Behaviors, Flexibility, and Handgrip Strength in Boys with Autism Spectrum Disorder: A Randomized Controlled Trial

Background/Objectives: Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by impairments in social communication and the presence of restricted and repetitive behaviors, often accompanied by motor impairments. Previous research indicates that regular physical exercise may reduce autism-related behaviors and improve motor competence. This study aimed to examine the effects of an adapted aquatic exercise program on autism-related behaviors, flexibility, and handgrip strength, key motor functions relevant to daily functioning. Methods: In this parallel-group randomized controlled trial, 35 boys with mild autism spectrum disorder (aged 8.4 ± 2.1 years) were enrolled. Participants were randomly assigned to an exercise group (n = 17) and a control group (n = 18). The exercise group completed a 16-week adapted aquatic exercise program (2 sessions/week, 50 min/session), while the control group received usual education only. The primary outcome was autism-related behaviors assessed by the Autism Behavior Checklist (ABC); secondary outcomes included flexibility and handgrip strength. Results: The exercise group showed significant improvements in Autism Behavior Checklist (ABC) scores, flexibility, and handgrip strength compared with the control group (p < 0.05). Large effect sizes were observed across all outcomes (partial eta squared, ηp2 > 0.14). These findings indicate that adapted aquatic exercise confers beneficial effects on behavioral and motor outcomes in children with mild ASD. Conclusions: Regular participation in adapted aquatic exercise reduces autism-related behaviors and improves flexibility and handgrip strength. These findings provide empirical support for the inclusion of aquatic exercise in intervention programs targeting children with ASD and may inform future research and practice.