Living in areas with good public transport links can increase physical activity by 90 minutes a weekBMJ 2016; 353 doi: http://dx.doi.org/10.1136/bmj.i1890 (Published 05 April 2016) Cite this as: BMJ 2016;353:i1890
People living in densely populated areas with a large number of public transport stops, public parks, and intersections are more likely to be physically active, a global study has found.1
The study, published in the Lancet, looked at 6822 adults aged 18-66 in 14 cities and towns around the world and found that those living in what it termed an activity-friendly neighbourhood took as much as 90 minutes more exercise a week than those who lived elsewhere. The researchers controlled for factors including age, sex, education, marital and employment status, and whether neighbourhoods were classed as high or low income.
The cities or towns included in the study were members of the International Physical Activity and the Environment Network: Ghent (Belgium); Curitiba (Brazil); Bogotá (Colombia); Olomouc (Czech Republic); Aarhus (Denmark); Hong Kong (China); Cuernavaca (Mexico); North Shore City, Waitakere City, Wellington, and Christchurch (New Zealand); Stoke-on-Trent (UK); and Seattle and Baltimore (USA).
On average, participants did 37 minutes a day of moderate to vigorous physical activity, equivalent to brisk walking. Residents of Baltimore had the lowest average daily rate of activity (29.2 minutes), and those in Wellington had the highest (50.1 minutes).
Researchers mapped out neighbourhood features from the areas around the study participants’ homes and found that factors including residential density and the number of street intersections, public transport stops, and parks were correlated with levels of physical activity. Participants wore accelerometers around the waist to measure their activity.
James Sallis, lead author of the study and professor of family and preventive medicine at the University of California, San Diego, said that areas with high residential density tend to have connected streets, shops and services, meaning that people are more likely to walk to local shops.
“Interestingly, distance to nearest transport stop was not associated with higher levels of physical activity, whereas the number of nearby transport stops was,” he said. “This might mean that with more options, people are more likely to walk further to get to a transport stop that best meets their needs. The number of local parks was also important since parks not only provide places for sport, but also a pleasant environment to walk in.”
He added that physical inactivity had been linked to diabetes, heart disease, and some cancers.
“Creating healthier cities could have an important impact on improving levels of physical activity. As part of their response to rising levels of non-communicable diseases, public health agencies should work with the urban planning, transport, and parks and recreation sectors towards making cities more activity-friendly than they are today,” said Sallis.
Despite its humid, subtropical climate Hong Kong’s activity levels were similar to those in New Zealand, said Ester Cerin, professor of public health at the University of Hong Kong and a coauthor of the study.
She said, “Hong Kong has very high residential density and good transport access. This combination means that people are more likely to walk to local services, or to catch a metro, bus, or boat on a daily basis. When done regularly, this kind of incidental physical activity accumulates and is an important contribution to overall levels of physical activity.”