Protocol for a quasi-experimental study examining the effect of a ball skills intervention on four domains of preschooler development.

Background: Preschooler inactivity and insufficient motor development have serious long-term consequences. The Chinese Ministry of Education launched a nationwide football-focused pilot project aimed at kindergartens in 2019 and issued the policy "Notice on the Establishment of National Football Kindergartens" in 2020. However, the impact of fundamental movement skills (FMS) interventions on other aspects of child development is unclear.