Published : 21 Sep 2026, 10:16 PM
Updated : 21 Sep 2026, 10:16 PM
The health benefits of exercising in cities generally outweigh the risks from air pollution, although experts have warned that choosing where and when to exercise can significantly reduce exposure, according to the BBC.
Air pollution is linked to heart disease, respiratory problems, cancer and an increased risk of early death. The BBC reported that fine particles known as PM2.5 can penetrate deep into the lungs, enter the bloodstream and travel to other parts of the body.
People who run or cycle in busy urban areas can inhale more pollution because exercise causes them to breathe faster and more deeply. Nitrogen dioxide, sulphur dioxide, carbon monoxide and ground-level ozone are among other pollutants found in urban air.
Audrey de Nazelle, an associate professor at Imperial College London, said exercise can still protect the body against some of the harmful effects of pollution.
A 2016 modelling study found that the health gains from walking and cycling outweighed the harms caused by dirty air. However, the BBC attested that at exceptionally high pollution levels, the risks can begin to approach or exceed the benefits of prolonged exercise.
A recent review found that exercising in polluted environments was associated with a 26 percent reduction in mortality risk compared with inactivity, although exercising in cleaner air was linked to a 31 percent reduction.
The level of pollution can nevertheless affect how much benefit people gain from exercise. A study involving healthy people and older adults with chronic lung or heart conditions found that those who walked in cleaner air showed greater improvements in lung and blood vessel function than those exposed to heavy traffic pollution.
Experts have recommended choosing parks, quieter roads and less congested routes where possible. Moving one or two streets away from heavy traffic can reduce pollution exposure by 20 to 30 percent, while one study found that using side streets instead of busy roads cut exposure by half.
Avoiding rush hour can also help because stationary traffic creates local pollution hotspots. On hot, sunny afternoons, people may also face higher levels of ground-level ozone.
The BBC report added that monitoring local air-quality indexes can help people decide when and where to exercise. On days with high pollution, experts have suggested exercising indoors or in parks.
People with conditions such as asthma or cardiovascular disease have been advised to take greater care when exercising outdoors in polluted areas.
Researchers have also stressed that individual choices can only reduce exposure to a limited extent. Haneen Khreis, an epidemiologist at the University of Cambridge, said the most effective protection would come from reducing emissions at their sources.
