Fundamental movement skills proficiency in preschool-aged boys and girls: Family matters.

To investigate the associations of fundamental movement skill (FMS) proficiency with family factors, including socioeconomic status (SES) and caregiver characteristics, by sex in young children in China. Participants included 1,207 Chinese children aged 3-6 years in this cross-sectional study. Children's FMS, consisting of locomotor skills and object control (OC) skills, were assessed. Information on family SES and caregiver characteristics was reported by the parents. Sex differences in outcomes and the associations of FMS with family factors by sex were examined using SPSS 26.0. Boys scored significantly higher than girls in terms of overall FMS and OC skills (both  < 0.01). There were significant and negative associations between children's FMS and parental education level and parental body mass index (BMI), which varied by sex. Boys who were regularly cared for by parents had higher FMS and OC skill scores than did those who were primarily looked after by grandparents (both  < 0.01). This complex interplay between sex and family factors (i.e. parental education level, parental BMI, and the identity of primary caregiver) on FMS proficiency in young children underscores the urgent need for developing sex-tailored, family-involved, and socio-culturally adapted interventions to enhance FMS proficiency at the preschool stage.