Countrywide natural experiment links built environment to physical activity

Nature, Published online: 13 August 2025; doi:10.1038/s41586-025-09321-3

By analysing the smartphone data of 2,112,288 participants, in particular observing and comparing the activity of the same individual in two different environments, we find that increases in the walkability of environments result in increases in daily physical activity, providing evidence of the importance of the built environment on physical health.