Media release

From: Springer Nature

Health science: City design affects physical activity

Urban environments that are designed to be easily navigable encourage physical activity, a study in Nature shows. Mobile phone data from more than 5,000 individuals across 1,609 cities in the United States reveal that average daily steps increase in areas deemed to be more ‘walkable’. The findings may guide policies to consider the importance of the built environment for the health of the population.

Although evidence suggests that the design of urban environments impacts physical activity, some studies have been limited by factors such as small sample sizes. Tim Althoff and colleagues analyse large-scale physical activity data from 2,112,288 users of a smartphone health app to measure how physical activity (step recordings) varies depending on the urban environment. They measure ‘walkability’ using the previously developed Walk Score based on proximity to amenities and measures of friendliness to pedestrians, such as block length and intersection density. Scores are on a scale of 1 to 100, where 100 is the most walkable.

The authors focused on data from 5,424 individuals who had relocated at least once within a 3-year observation period across 1,609 cities. Moving from a less walkable to a more walkable area is shown to result in an increase in physical activity, and vice versa. For example, 178 people moving from a 48/100 city to New York City (score 89/100) increased their physical activity by 1,400 steps from 5,600 to 7,000 average daily steps. This effect was mirrored for participants relocating in the opposite direction. These observations remained consistent across different genders, ages and body mass index values.

The authors go on to perform simulations to predict how increasing the walkability of urban areas might increase physical activity. They predict that if everyone in the United States lived in a city with a walkability score of Chicago or Philadelphia (78/100), 11.2% more Americans may meet the recommended aerobic physical activity guidelines. These findings provide robust evidence supporting the importance of the built environment (such as decreasing car dependency or improving public transportation) in directly improving health-enhancing physical activity, the authors conclude.