This case report describes the effectiveness of Autism Fitness® used with four children diagnosed with Autism Spectrum Disorder (ASD). Research has shown physical activity assists to decrease social, behavioral, cognitive, and motor impairments as well as reduce maladaptive behaviors in those with ASD.1Despite these findings, there is lack of consensus on the most appropriate fitness model. Autism Fitness® was chosen as the intervention for this case report. Autism Fitness® is a standardized, progressive fitness model designed for use with individuals across the autism spectrum. Fitness activities were conducted over a course of seven-eight weeks by a third-year Doctor of Physical Therapy Student who was certified in the Level 1 Autism Fitness® program. The effectiveness of this intervention was observed through improvements in strength, stability, and the ability to progress exercises in those diagnosed with ASD. After seven-eight weeks, all athletes, some greater than others, demonstrated improvements in physical fitness and reduced maladaptive behavior such as increased attendance to task and ability to perform exercises with less prompting/demonstration. Parent survey results demonstrate that the athletes gained a greater appreciation for fitness and the parents were interested in performing the exercises with their athletes following the cessation of the program.