# Motor skills influence social function through health-related fitness in children with autism: a cross-sectional study

## TL;DR

This study finds that physical fitness, especially strength and flexibility, helps explain how motor skills relate to better social functioning in children with autism.

## Contribution

The study identifies health-related physical fitness as a mediator between motor skills and social functioning in children with ASD.

## Key findings

- Higher fundamental motor skills scores correlate with better social functioning in children with ASD.
- Health-related fitness components like handgrip strength and flexibility mediate the relationship between motor skills and social functioning.
- Integrating strength and mobility training with motor-skill practice may improve social outcomes for children with ASD.

## Abstract

To examine whether health-related physical fitness mediates the association between fundamental motor skills (FMS) and social functioning in school-age children with autism spectrum disorder (ASD).

A total of 117 school-age children with ASD were recruited from special education schools. FMS were assessed using the Test of Gross Motor Development–3 (TGMD-3). Social functioning was evaluated using the Social Responsiveness Scale–2 (SRS-2), with higher scores indicating greater social impairment. Health-related physical fitness was assessed via body mass index, flexibility (sit-and-reach), muscular strength (handgrip), muscular power (standing long jump), balance (one-leg stance), and vital capacity. Pearson correlation analyses and structural equation modeling with bias-corrected bootstrapping (5,000 resamples) were conducted to test mediation effects.

Higher FMS scores were associated with lower SRS-2 scores, indicating better social functioning (r = −0.312, p < 0.001). Several health-related physical fitness components, particularly handgrip strength and flexibility, were significantly associated with both FMS and social functioning. Structural equation modeling demonstrated a full mediation effect, whereby health-related physical fitness significantly transmitted the association between FMS and social functioning (indirect effect B = −2.111, 95% CI [−3.576, −1.189]), while the direct effect was not significant (B = −0.095, 95% CI [−1.193, 1.274]). Model fit indices indicated an excellent fit.

Health-related physical fitness, especially muscular strength and flexibility, appears to be a key mechanism linking motor skill proficiency to social functioning in children with ASD. Interventions that integrate strength and mobility training with motor-skill practice may enhance social outcomes in this population.