Are you getting robbed on your run?
This is Sandra Tsing Loh with the Loh Down on Science.
Exercise beats back death. But what if you run in dirty air? Does the bad cancel the good?
Enter Po-Wen Ku and team from Taiwan and University College London.
First, they pooled past studies covering ONE-POINT-FIVE MILLION adults worldwide. Then they zoomed in on the UK and Taiwan. They matched each person’s exercise to the air they breathed.
AND? Plot twist! In clean air, exercise cut death risk by THIRTY PERCENT! But dirty air? Just TWELVE. Same sweat. Less than half the benefit!
So keep moving – it still helps! Just pick the park over the busy road… when you can.
Ku, P-W., Steptoe, A., Hamer, M., et al. (2025). Does ambient PM2.5 reduce the protective association of leisure-time physical activity with mortality? BMC Medicine, 23, 647. https://doi.org/10.1186/s12916-025-04496-y