Researchers from Imperial College London say that slogging it out on a treadmill indoors (however mundane) may actually be more beneficial to your workout than taking it outside.
119 people over the age of 60 were asked to talk a two-hour walk through Hyde Park and Oxford Street, which is notorious for being one of the most traffic-heavy spots in the UK.
The lung capacity and arterial stiffness of each participant were monitored before and during the experiment, as were the air pollution levels.
After spending just 60 minutes in the park, there was a 7.5 per cent improvement in the amount of air the participants could expel in one breath and their arteries became 24 per cent less stiff. But interestingly, the increase in blood flow that is usually seen during exercise was noticeably absent after the stint on Oxford Street.
The study associates this to “greater exposure to black carbon soot and ultrafine particles from diesel exhaust.”
“Our findings indicate that in traffic-congested streets… the health benefits of walking do not always outweigh the risk from traffic pollution,” explains senior author Professor Fan Chung, from the National Heart & Lung Institute.
“It shows that we can’t really tolerate the levels of air pollution that we currently find on our busy streets.”
Although this particular study solely looks at the effect of air pollution on the ageing population, Dr Chung emphasises that the wider community is not immune.
“These findings are important as for many people, such as the elderly or those with chronic disease, very often the only exercise they do is to walk,” he says.
“We suggest that, where possible, older adults walk in parks or other green spaces away from busy roads.”