How air pollution affects exercise performance doesn’t get as much attention as it deserves. It is a rather complex subject, although it seems rather intuitive that the more polluted the air, the worse it is for exercise. Although air pollution is everywhere, it is far worse in urban centers, with most of it coming from vehicle exhaust.
On this issue, it appears that science agrees with our intuition. According to this study – Subclinical Effects of Aerobic Training in Urban Environment, which compared people trying to improve their aerobic fitness in urban and rural settings, both groups became equally fit, though reaction times were better in rural settings and the urban exercisers had significantly higher levels of inflammation markers(exercise even in a non-polluted area can cause inflammation, it’s just worse in polluted areas).
I don’t believe the lesson to be learned from this is to not exercise if you live in a polluted area, unless you have respiratory disease, but rather to be more cautious or try to seek out an area with cleaner air to exercise if possible.
Also, I think it could be possible to prevent the inflammation caused by pollution by eating better. Some foods have a pro-inflammatory effect, like food with a high saturated fat content, as well as fried, roasted and overly processed foods. On the other hand, many fresh fruits and vegetables either have a neutral effect on inflammation or can help prevent it from getting out of control. Curcumin, a natural compound which is found in turmeric(an important ingredient in curry), has potent anti-inflammatory effects. Ginger, a close cousin of turmeric has similar benefits. Leafy greens may also help. Try to get all this from food, not supplements.
Besides this, if you are a runner living in an urban environment, try to stay far away from highways or areas with heavy traffic when running. In my personal experience, it seems that I’ve had to apply more effort when running in polluted areas than in non-polluted areas to achieve my usual pace. Also, the study I cited seems to suggest that air pollution would have more of an effect on jogglers than runners, since air pollution interferes with reaction rates/cognition during aerobic exercise. In my experience, I am more likely to drop the balls in polluted areas.
Do not let this discourage you from exercise, unless you have medical issues.