Effects of an innovative daily physical activity intervention on the health and fitness status of primary school children: a cluster randomized controlled trial

AimsAn important barrier for a nationwide implementation of a daily physical activity (PA) intervention at primary schools is the lack of spatial and human resources. Therefore, the aim was to develop an innovative PA intervention that can be implemented, without additional spatial and human resource requirements. The effects of this intervention on anthropometrics and health-related fitness of primary school children were investigated.MethodsIn twelve primary schools, 24 classes were randomly allocated to an intervention and control group. In the intervention group, children received mix physical education lessons, cognitive content using movement, and additional opportunities for extracurricular physical activities (home exercises) over a 9-month period. In the control group, children received the usual physical education classes. At baseline (Sept 2021) and at follow-up immediately after the intervention (June 2022), body weight, height, waist circumference and fitness parameters (cardiorespiratory fitness, muscle strength, flexibility) were measured. Intervention effects were assessed using multilevel regression models, adjusted for gender, urban/rural school, sports club membership, and for baseline values of the outcome parameter. Interactions between intervention and being a member of a sports club were assessed.ResultsOf 485 invited children, 412 (85%) were included in the analyses; 228 in the intervention and 184 in the control group. Children were 9.7 (SD 0.5) years old at baseline. In the total intervention group, a reduction in waist-to-height ratio and increase in all fitness parameters were found compared to the control group. Interactions with being a member of a sports club were found, and intervention effects were more pronounced in the group of children who were not a member of a sports club.ConclusionsOur daily physical activity intervention for primary schools showed positive effects on important health related parameters, especially for children who were not in a sports club and had most of their PA at school. Wider implementation of this intervention in primary schools is warranted, which should be feasible, since we made sure that no extra resources are needed.Trial registrationDRKS00025515.