Reduced Cardiorespiratory Capacity in Children with Autism Spectrum Disorders

Background—Children with autistic spectrum disorders (ASDs) are frequently hampered by motor impairment. It limits them from regularly practicing physical activities and results in a lower physical fitness even though low cardiorespiratory fitness is one of the most important predictors of all-cause mortality. This study aimed to investigate the cardiorespiratory fitness of boys with ASD compared to typically developed children. Methods—forty male children participated. Twenty were control children (CONT—10.0 ± 1.6 years) and 20 were ASD children (ASD—10.7 ± 1.2 years; intellectual quotient > 70). All participants completed an incremental exercise test on a treadmill. An evaluation of motor characteristics by three tests was conducted (muscular strength; explosive power; flexibility). Assessments of daily physical activity were obtained by questionnaires (PAQ-C) and by actigraphy. Results—in the ASD group, aerobic capacity values (VO(2peak)), effort duration and maximal speed were significantly lower compared to CONT (p < 0.05). Flexibility, explosive power and muscular strength were significantly lower in ASD compared to CONT (p < 0.05). Similarities between all children were observed for physical activity evaluation by actigraphy and with the PAQ-C. Conclusions—children with ASD had lower cardiorespiratory fitness than CONT despite similar physical activity levels. Our results suggested that the difference may be due to motor discrepancies.