A new international study has found that the benefits of walking and cycling outweigh the dangers from air pollution in almost all global cities.
Only one per cent of cities have such high levels of air pollution that walking and cycling would pose a danger to a health. Even in heavily-polluted cities like Delhi (India) an individual would have to cycle for over five hours per week before exposure to pollution would cancel out health benefits from physical activity.
The researchers modelled the impact of cycling and walking in different levels of pollution and established a tipping point and a break-even point. The tipping point is the length of time after which there is no further health benefit from active mobility, and the break-even point is when harm from pollution begins to outweigh health benefits.
‘While this research demonstrates the benefits of physical activity in spite of air quality, it is not an argument for inaction in combatting pollution,’ said Dr James Woodcock from the Cambridge-based Centre for Diet and Activity Research.