Background/Objectives: Food selectivity is a prevalent and challenging issue in childhood, particularly in children with autism spectrum disorder (ASD), which may result in restricted dietary patterns and nutrient deficiencies. This study aimed to identify high-risk subgroups of children by combining food selectivity, diet, BMI, gastrointestinal symptoms, sensory processing, and parental feeding practices in children with ASD and in typically developing children (TDC). Methods: To achieve this aim, we ran a cross-sectional, survey-based study, including 408 children (aged 3 to 12.11 years), with gender-matched groups. Both parents completed a survey on children’s diet, anthropometric curves, gastrointestinal symptoms, and the Brief Autism Mealtime Behavior Inventory (BAMBI), Short Sensory Profile (SSP), and Caregiver’s Feeding Style Questionnaire (CFSQ). Data analysis included comparative tests, correlations, and k-means cluster analysis. Results: Children with ASD exhibited significantly greater sensory processing difficulties, higher food refusal, limited food variety in the diet, and autism-related mealtime characteristics compared with TDC across all age groups. Caregivers of children with ASD reported higher controlling and contingency management feeding practices compared to the parents of the TDC. We found a strong correlation between sensory sensitivities and feeding issues. Notably, Body Mass Index (BMI) was not significantly associated with dietary restriction or gastrointestinal symptoms. Cluster analysis revealed a high-risk sub-phenotype in both groups of children with some differences, characterized by high food selectivity, taste, tactile, and smell sensitivity, gastrointestinal symptoms, and overactive parental practices. Conclusions: The early identification of this subgroup might foster more tailored, multidisciplinary, and effective assessment and clinical intervention.

Research on physical activity (PA) interventions for individuals with autism spectrum disorder (ASD) has shown benefits in various domains, yet questions remain about how to implement such interventions in adolescents effectively. This study case-series study explores the contribution of a PA program integrated with applied behavior analysis (ABA) strategies in improving motor skills and reducing repetitive behaviors in three adolescents with ASD. The study used a pre-post case series design, with assessments at three time points (baseline, 6 months, and 9 months). The intervention consisted of 29 two-hour training sessions, held once a week in a public gymnasium. Standardized tools, including the Checklist for Autism Spectrum Disorder (CASD), the Social Responsiveness Scale (SRS-2), the Vineland Adaptive Behavior Scales (VABS), the Repetitive and Restricted Behavior Scale (RRBS), and the Movement Observation and Valuation for Individual Training (MOVIT), were utilized. Participants showed consistent improvements in all six motor skills evaluated by the MOVIT, with individual variations. The most significant gains were observed in intersegmental coordination, with acquisition rates increasing from 70% to 90%. Repetitive behaviors decreased, particularly restricted behaviors and modulation insufficiency, while changes in sensorimotor stereotypies were more modest. The preliminary results suggest that a PA program integrated with behavioral strategies is efficacious in improving motor skills and reducing repetitive behaviors in adolescents with ASD. These findings support the integration of physical activity into comprehensive educational interventions for this population.