Air pollution cancels positive benefits of exercise for seniors
Science has proven that it’s crucial for seniors to stay active as they get older. But what happens when the environment you’re exercising in is toxic enough to counter those health benefits? In cities with heavy air pollution, this may very well be the case.
A new study conducted by scientists from Imperial College London and Duke University found that adults over 60 lost all benefits of walking for two hours when subjected to short-term exposure to traffic exhaust and street pollution.
The study was published in the journal The Lancet and is the first study of its kind to look at exposure to pollution canceling out the benefit of exercise on both healthy patients and those with cardiorespiratory illnesses like coronary heart disease.
The research found that that exposure to busy city streets and traffic pollution countered the the positive effects of moderate exercise like walking, but that walking in parks significantly improved health and wellbeing.
“Combined with evidence from other recent studies, our findings underscore that we can’t really tolerate the levels of air pollution that we currently find on our busy streets,” said Fan Chung, Professor of Respiratory Medicine and Head of Experimental Studies in Medicine at the National Heart & Lung Institute at Imperial College. “We call for greater access to urban green spaces for people to exercise.”
For the study, the researchers asked 119 volunteers over 60 years old who were either healthy or had a preexisting cardiorespiratory condition to walk for two hours during the day.
The participants either walked in Hyde Park in London or a busy section of Oxford Street. Pollution levels in Oxford Street often exceed air quality limits set by the World Health Organization.
The researchers took physical measurements before and after the walks so they could see how the exercise impacted the participants’ blood pressure, lung capacity, and arterial stiffness.
The study volunteers who walked in Hyde Park showed significant improvement in lung capacity within the first hour and the effects lasted even after the walk was completed.
Walking along Oxford Street had a small impact on lung capacity, but it didn’t match nearly those that were in Hyde Park.
Healthy participants experienced a 24 percent reduction in arterial stiffness, and patients with preexisting conditions saw a 19 percent reduction when walking in Hyde Park. Those who walked on Oxford Street experienced much smaller reductions in arterial stiffness.
Even when accounting for the stress-inducing environment of crowded Oxford Street, and the medications that some of the participants took, the results show the lasting positive effects that walking in non-polluted areas has on respiratory health.
The study also highlights the importance of urban green spaces and reducing pollution in major cities.