Secular change in selected motor performance parameters and BMI in Swiss primary school children from 2014-2021: the Sportcheck+ study

Background
Motor performance is known to be a meaningful marker for healthy child development. It is therefore important to monitor secular trends in children's motor performance, as healthy and physically active children are more likely to be healthy and physically active during adulthood. However, studies with regular and standardized monitoring of motor performance in childhood are scarce. Additionally, the impact of Covid-19 mitigation measures on secular trends is unknown.
Methods
The aim of this study was to describe secular changes in motor performance (balancing backwards, jumping sidewards, 20-m sprint and 20-m Shuttle Run Test (SRT)) and anthropometric data (BMI) in Swiss first graders from 2014 to 2021. The sample included a total of 10’953 children. Multilevel mixed-effects models were used to estimate secular trends for boys vs. girls, lean vs. overweight as well as fit vs. unfit children. The influence of Covid-19 mitigation measures was also analysed.
Results
Balance performance decreased (2.8% per year), whereas we found improvements for jumping (1.3% per year) and BMI (-0.7% per year). 20-m SRT performance increased by 0.6% per year in unfit children. Secular trend revealed enhanced jump performance development for boys when compared to girls, but also more pronounced decrease in 20-m SRT in fit girls compared to fit boys. Covid-19 was associated with increased BMI, but motor performance was not negatively affected.
Conclusion
In our sample, secular changes in motor performance show promising tendencies from 2014 to 2021. The effects of Covid-19 mitigation measures on BMI should be monitored in additional birth cohorts and follow-up studies.