Muscle strength and executive function in children and adolescents with autism spectrum disorder.

The development of effective (non-pharmacological) treatment approaches for executive dysfunction in autism spectrum disorder (ASD) requires evidence that factors influencing this domain can be modified by behavioral interventions. The present cross-sectional study investigated the relative associations of ASD, muscle strength and body mass index with executive function and information processing among the Healthy Brain Network cohort. Patients with ASD (N = 174) and healthy peers (N = 202) aged 5 to 18 years completed cognitive tasks of the NIH toolbox (Pattern Comparison, Flanker, List Sorting, Card Sorting) to assess core components of executive function and information processing. Additionally, anthropometrics and muscle strength were collected from selected items (push-ups, curl-ups, trunk lift, and grip strength) of the Fitnessgram battery. Based on structural equation modeling, ASD was related to impaired muscle strength and executive function, when confounders (age, sex, pubertal status, and socioeconomic status) were accounted for. Muscle strength further showed independent contributions to information processing and executive function. This association was moderated by ASD, so that higher muscle strength was related to higher executive function in ASD patients only. The present findings provide a first indication that the promotion of muscle strength may have the potential to generally enhance information processing and to reduce ASD-related executive dysfunction in children and adolescents. LAY SUMMARY: In comparison to healthy peers, children with ASD showed impairments in executive function and muscle strength. Moreover, higher muscle strength was independently associated with better executive function, but only in ASD patients. This is a first indication that the promotion of muscle strength, for example, by regular exercise, could contribute to a reduction of ASD-related executive dysfunction.