The impact of sports and nutrition interventions on the bodyfat and BMI of primary school children (compared to the effects of a lockdown period while Covid19-pandemic)

Abstract

Background & Aims

The increasing rates of overweight and obesity highlight the need for prevention. The EDDY prevention study aimed to assess whether a school-based program with sports and nutrition interventions could improve the lifestyle of elementary school children in Vienna, Austria.

Methods

During the school year 2018/19, 146 children (8–11 years) were assigned to an intervention group (I1, n=73) or control group (C1). In 2019/20, 130 children were included as a second control group (C2) during the COVID-19 pandemic. Only the intervention group received weekly nutrition and physical activity lessons for 5 months. Weight, height, and body fat were examined at baseline and the end of the project. Body fat was determined by bioelectric impedance analysis using a multi-frequency segmental body composition analyzer. Changes in body fat percentage and BMI after the intervention were compared between groups using Wilcoxon or Student T-Test. Additionally, comparisons were performed with the control group exposed to the first COVID-19 lockdown, where no intervention occurred.

Results

The baseline median BMI for the I1 was 20.3 (14.9–30.6) kg/m², while the C1 was 18.5 (14.0–26.3) kg/m². After the intervention, a significant modest reduction in body fat percentage (P < 0.01) was achieved [−1.35 (−4.20–0.90) %], compared to C1 [0.10 (−2.90–3.00) %] and C2 [1.88 (−2.55–7.51) %]. Significant differences in BMI changes were observed only between the I1 [0.44 (−1.29–1.84) kg/m²] and the C2 [1.31 (−0.49–3.27) kg/m²] (P < 0.01).

Conclusions

A 5-month health intervention promoting nutritional education and additional physical activity in schoolchildren from Vienna positively affected body fat percentage, highlighting the importance of adjusting the school system. The additional challenges of the COVID-19 lockdown were evident in fat mass and BMI, illustrating the dramatic consequences of a lack of daily structure and the important influence of the family environment. Differences in BMI and body fat development suggest the importance of assessing body composition to monitor children's nutritional status.