Children's light physical activity is associated with a healthy cortisol decrease when classes are taught in a forest setting

A recent cooperation study (University of Heidelberg, University of Stavanger, University of Mainz, and TUM) focused on the relationship between students’ physical activity and their cortisol as well as cell free DNA (cfDNA) response during indoor and outdoor classes. Fifth grade students (N = 37) in the intervention group experienced regular Education Outside the Classroom (EOtC) in a nearby forest one day a week in the school year 2014/2015; students in the control group (N = 11) had normal indoor classes. Bayesian hierarchical linear models and a compositional data analysis approach were applied to account for the multicollinearity between the variables. A positive association was found for relatively high levels of light physical activity and a steady cortisol decrease in the intervention group; the association was independent of students’ sedentary behaviour and moderate-to-vigorous physical activity. While experiencing the same level of light physical activity, no association between light physical activity and cortisol was found for the control group in the indoor setting. A high amount of cfDNA was positively associated with a relatively high amount of sedentary behaviour in the intervention group. No clear trends were found for the other variables. The combination of nature and physical activity during EOtC seems to be beneficial in terms of the students’ health. The study was funded by a grant of the Dietmar Hopp Foundation (grant number 23016007).

An open-access version of the publication is available under: https://www.frontiersin.org/articles/10.3389/fpubh.2019.00026/full 

Becker, C., Schmidt, S., Neuberger, E. W. I., Kirsch, P., Simon, P., & Dettweiler, U. (2019). Children's Cortisol and Cell-Free DNA Trajectories in Relation to Sedentary Behavior and Physical Activity in School: A Pilot Study. 7(26). doi:10.3389/fpubh.2019.00026