If you use your area’s air pollution as a reason not to exercise, you might need to find a better excuse.
Even in heavily polluted areas, the benefits of exercise outweigh the harmful effects of air pollution in relation to the risk of premature mortality, a new study reports.
“Even for those living in the most polluted areas of Copenhagen, it is healthier to go for a run, a walk, or to cycle to work than it is to stay inactive,” says Zorana Jovanovic Andersen, associate professor with the Centre for Epidemiology and Screening at the University of Copenhagen.
It is well known that people who engage in physical activity are less likely to die prematurely—and also that air pollution increases the risk of premature death. Physical activity amplifies respiratory intake and accumulation of air pollutants in our lungs, which may increase the harmful effects of air pollution during exercise.
“Air pollution is often perceived as a barrier to exercise in urban areas. In the face of an increasing health burden due to rising physical inactivity and obesity in modern societies, our findings provide support for efforts in promoting exercise, even in urban areas with high pollution,” Jovanovic Andersen says.
“However, we would still advise people to exercise and cycle in green areas, parks, woods, with low air pollution, and away from busy roads, when possible,” she adds.
This is the first large population-based, prospective cohort study that has examined the joint effects of both physical activity and air pollution on mortality. It is based on high quality data on both physical activity and air pollution exposure.
The new study, published in Environmental Health Perspectives, includes 52,061 subjects, aged 50-65 years, from Aarhus and Copenhagen who participated in the cohort study Diet, Cancer and Health.
From 1993-97, they reported on their physical leisure activities, including sports, cycling to/from work, and in their leisure time, gardening and walking. The researchers then estimated air pollution levels from traffic at their residential addresses.
Of the participants, 5,500 died before 2010. The study shows about 20 percent fewer deaths among those who exercised than among those who didn’t exercise, even for those who lived in the most polluted areas, in central Copenhagen and Aarhus, or close to busy roads and highways.
“It is also important to note that these results pertain to Denmark and sites with similar air pollution levels, and may not necessary be true in cities with several fold higher air pollution levels, as seen in other parts of the world,” Andersen says.
About the Lead Author of the Study
Zorana Jovanovic Andersen is an associate professor with the Centre for Epidemiology and Screening at the University of Copenhagen.