London (dpa) - Joggers, cyclists and other people doing outdoor workouts may be losing out on health benefits, lower cancer risk and added life expectancy if they exercise in polluted city air, new research suggests. Using health data covering 1.5 million people across several countries, a team of scientists, including from University College London (UCL) and City University of Hong Kong, has found that the effects of regular exercise appear to be reduced among people living in high-pollution areas. The usual "protective effect" that running offers from the risk of death from cancer and heart disease is diminished when the level of fine particulate matter in the air topped 25 micrograms per cubic metre, the researchers said. The implications of the findings will be sobering to millions of joggers worldwide, since almost half the world’s population lives in places where levels of fine particulate matter are this high or higher. "Our study shows that toxic air can to some extent block the benefits of exercise, although not eliminate them," said Andrew Steptoe of UCL, who warned that the findings provide "further evidence of the damage that fine particle pollution can do to our health." In their paper on the subject, published in the journal BMC Medicine in November, the team warned that many people live in cities where the pollution level exceeds 35 micrograms, or even reaches 50 or more. When the air is that clogged with tiny particles, the health benefits of outdoor exercise are "less evident," they warned. However, the research shows that going for a run in the park "remains beneficial even in polluted environments," according to Po-Wen Ku of National Chung Hsing University in Taiwan. At the same time, the gains brought about by such exercise could be enhanced by improving urban air quality. Some 4 million people die prematurely every year as a result of prolonged exposure to outdoor air pollution, according to the World Health Organization. The following information is not intended for publication dpa spr coh (The article has been published through a syndicated feed. Except for the headline, the content has been published verbatim. Liability lies with original publisher.)
