Objective: The goal of this cross-sectional study was to further explore the relationships between motor competence, physical activity, perceived motor competence, physical fitness and weight status in different age categories of Dutch primary school children. Methods: Participants were 2068 children aged 4 to 13 years old, divided over 9 age groups. During physical education classes, they completed the 4-Skills Test, a physical activity questionnaire, versions of the Self-Perception Profile for Children, Eurofit test and anthropometry measurements. Results: Results show that all five factors included in the analyses are related to each other and that a tipping point exists at which relations emerge or strengthen. Physical fitness is related to both motor competence and physical activity and these relationships strengthen with age. A relationship between body mass index and the other four factors emerges in middle childhood. Interestingly, at a young age, motor competence and perceived motor competence are weakly related, but neither one of these have a relation with physical activity. In middle childhood, both motor competence and perceived motor competence are related to physical activity. Conclusion: Our findings show that children in late childhood who have higher perceived motor competence are also more physically active, have higher physical fitness, higher motor competence and lower body mass index. Our results indicate that targeting motor competence at a young age might be a feasible way to ensure continued participation in physical activities throughout childhood and adolescence.

The authors have declared no competing interest.

This work was supported by a grant for AU from the Netherlands Organization for Scientific Research (NWO) (grant number 023.013.055). https://www.nwo.nl/ The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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Ethics Committee of Tilburg University

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For our funding application we have decided (in collaboration with our data steward) that data would not be made publicly available, only Metadata would be made available through Figshare. Parts of the dataset that are suitable for reuse, would be made available on request via a restricted license. This is decided due to the following: - the data contain personal identifying information - the consent letters to the parents describe who have access to their children's information. (we did not include online data availability) We therefore strongly hope that we can publish the results of our study without having to come back from these decisions: we would publish the metadata in Figshare and specific data would be available on request.