It's always a matter of doubt whether to take a bike or the bus for work. Rising air pollution rates encourage people to drive more and walk less in the rural areas. But a new study suggests that walking or cycling are always the healthiest options no matter whether the city is polluted or not.
The study published in the Journal Preventive Medicine reported that active lifestyle outweighs the effects of air pollution. Walking or cycling boosts heart and bone health. Most people think that breathing hard while exercising lets in more dirty air but it may not be so.
Researchers from the University of Cambridge combined data on the effects of exercise on life expectancy with pollution readings from cities all over the world. They found that risks of air pollution could be overcome by cycling or walking 30 minutes every day even in polluted cities.
"Even in Delhi, one of the most polluted cities in the world - with pollution levels 10 times those in London - people would need to cycle over five hours per week before the pollution risks outweigh the health benefits," said Dr. Marko Tainio, the lead author of the study.
"We should remember, though, that a small minority of workers in the most polluted cities, such as bike messengers, may be exposed to levels of air pollution high enough to cancel out the health benefits of physical activity."