Does Air Pollution Negate the Health Benefits of Walking?

You don't need an expensive gym membership to exercise. While it certainly opens the doors to more possibilities, all you need to exercise is a pair of athletic shoes and the good outdoors. Assuming the weather is nice, you can go outside and walk as a form of cardio. Walking burns calories and fat while simultaneously improving your heart and lung function. However, there's new concern regarding the negative effect of air pollution when walking.

For the study, U.K. researchers followed 119 men and women over age 60. About half of the participants were generally health, while the other half were suffering from chronic obstructive pulmonary disease (COPD). As you may already know, COPD is a type of inflammatory disease that affects the lungs and respiratory system.

Researchers asked one group of participants to walk for about two hours a day in the heart of London. Not surprisingly, the area is heavily congested with traffic. The other group of participants was asked to walk for two hours in Hyde Park, which has virtually no traffic At the end of eight weeks, researchers asked participants to switch their routes. Throughout the study, researchers monitored both groups of participants as well as the environmental pollution in their respective walking routes.

So, what did they find? Researchers found that walking in Hyde Park offered numerous health benefits, including increased lung capacity and arterial stiffness. On the other hand, walking in the heart of London resulted in minor improvements to lung capacity as well as worsening arterial stiffness. Because of these nuances, researchers concluded that air pollution can essentially negate some of the health benefits of walking.

"In London, we have a lot of open spaces, green space, where the amount of pollution is going to be less than what it is outside the park. If that’s not available, people should probably exercise indoors," said lead researcher Kian Fan Chung, who workers as a professor at the Imperial College of London's National Heart and Lung Institute.

This doesn't necessarily mean that you should stop walking. Walking remains one of the easiest and most effective forms of cardio exercise. However, this study sheds light on the potential negative effects of air pollution. So, if you're going to walk (or run), choose a route with minimal traffic. The more traffic, the greater the risk of air pollution.

This study was published in the journal Lancet.