Associations between walkability and physical activity among children and adolescents: evidence from a gamified intervention.

Children and adolescents often do not meet the WHO´s physical activity (PA) recommendations. As many of them live in urban areas, these are important spaces for PA-promotion. Objective measures such as the Walkability Index are often used to assess urban spaces in terms of their PA friendliness. However, it is unclear whether such parameters can predict PA behavior of children and adolescents. This study examines the relationships between the Walkability Index and data of the intervention "Kreuz & Quer" (K&Q), promoting PA. K&Q collected data from 9,852 children and adolescents in urban neighborhoods. PA was measured through the number of interactions at K&Q checkpoints, reflecting participants' actively performed visits to physical locations. PA acted as the dependent variable in a linear mixed models approach. Walkability served as a fixed factor and district, season of year and intervention day as random effects. Results indicate a significant positive association between a high Walkability Index and PA levels in children and adolescents. Some of the observed variance can be explained by the random effects. There is still unexplained variance, suggesting the need to consider additional influences to explain youth PA behavior. These may include qualitative explanations to provide a holistic picture. Subjective perspectives can help create environments that are structurally conducive to walking, thereby promoting PA.