Regular physical activity protects long-term health even in polluted air, but pollution can blunt the size of the benefit. Timing and placing exercise to avoid pollution peaks helps preserve it.
General
A meta-analysis covering 1.5 million adults found meeting recommended physical-activity levels cut all-cause mortality risk by about 30% where PM2.5 was below 25 µg/m³, but only by 12–15% at higher pollution levels — exercise stayed beneficial, with air quality shaping the size of the benefit (Ku et al., 2025).
A meta-analysis of eight studies covering more than 1.4 million people found that physical activity in polluted air was still associated with a 26% lower risk of death, close to the 31% reduction for physical activity in clean air (Martin et al., 2025).
