This simple running tip can instantly reduce your exposure to traffic pollution in built-up areas

Running is great for your lungs. But when your runs take place alongside busy roads, air pollution can become a problem.

A recent study found that heavily polluted air slowed marathon finish times by more than seven minutes for both men and women.

But the stakes are much higher than your finish time.

‘All of the organs in the body seem to be affected in some way by breathing in air pollution,’ says Professor Frank Kelly, director of the Environmental Research Group at King’s College London.

‘It’s estimated that those who die prematurely in the UK are losing, on average, six months of life due to air pollution exposure,’ he says. ‘The people who die prematurely in London may be dying up to 10 years earlier than they should.’

That’s not to say you should stop running, of course. The health benefits of exercise still outweigh the risks of exercising in polluted environments.

‘Being sedentary is also very harmful to your health,’ says Michael Koehle, head of the University of British Columbia’s Environmental Physiology Lab in Vancouver, Canada, and a leading expert on exercise and air pollution. ‘An active lifestyle always outweighs an inactive lifestyle. Active individuals living in more polluted parts of the city still have fewer health problems than sedentary people living in the same area and exposed to the same pollution.’

The key, then, is to reduce your exposure wherever you can – and one of the simplest strategies couldn't be easier.

Pollution levels are highly localised, meaning even moving a few metres away from traffic can make a difference. So, if you have to run along a busy road, stick to the far side of the pavement, furthest away from the traffic.

‘Keeping some distance between you and heavy traffic is a good thing,’ says Edward Avol, professor of environmental health at the University of Southern California, who has spent his career studying the effects of air pollution.

‘Even running parallel to a busy street on a less-travelled block could be an effective mitigation strategy.’

Other simple ways to reduce your exposure include running early in the morning or later in the evening, when pollution levels are generally lower than during rush hour, and making the most of local parks. Not only do they move you further away from traffic, but trees also help absorb pollutant gases and filter harmful particles from the air.