Everyone knows walking and bicycling is good for the health of a community, but how good? And how can city planners measure those impacts to champion bicycle and walking infrastructure?
At the University of Wisconsin-Madison Global Health Institute, Samuel Younkin, lead researcher for the Initiative for Health-Oriented Transportation (HOT), and colleagues created a new model that measures how active travel benefits health at a population level and gives policy makers and city planners a new tool to help bring health into the decision-making process.
“The goal is to inject health into the discussion about transportation design,” Younkin says. “To do that, we need models that produce measurable evidence of the health benefits.” The new Health-Oriented Transportation Model, published late last year in the Journal of Transport and Health, does so by estimating the health benefits of travel-related walking and bicycling that has been reported in large-scale travel surveys.
The need is evident, according to the paper that identifies the lack of physical activity as the top, modifiable risk factor for chronic diseases from heart disease to diabetes. “The health benefits of physical activity are well established, yet due, in part, to pressures that arise from automobile-oriented environments, approximately 23 percent of the world’s population does not meet recommended levels of physical activity,” the paper continues. “The world’s population is increasingly concentrated in urban settings in which urban planning and design play important roles in active transportation achieved by a community.”
“Quantifying the health benefits of replacing automobile-dependent, sedentary lifestyles with active biking and walking offers major population-wide gains by promoting daily exercise,” says GHI Director and co-author Jonathan Patz, who holds joint faculty appointments in the Nelson Institute for Environmental Studies and the Department of Population Health Sciences. “Additionally, transportation represents our nation’s largest greenhouse gas-emitting sector contributing to the global climate crisis.”
“The goal is to inject health into the discussion about transportation design.”—Researcher Samuel Younkin
The HOT model uses travel survey data (data collected when people are asked about their travel) and looks at variables including the proportion of people who walk or bike, the strenuousness of the activity and the weekly rate of activity. Using that information, planners and policy makers can use the model to predict what would happen to health outcomes in a community if any of the variables is changed. City planners, for example, could quantify how much increasing access to walking and biking could potentially lower the death rate in the area.
It’s the only model that directly links travel data with health outcomes, Younkin says. “Using the model can impress upon people the magnitude of the health impacts, so quantifying the benefits was a critical first step.” In London, for example, the model showed that if everyone walked and biked, there would be a two percent reduction in the death rate.
The team also wanted to create a transparent methodology that could be used widely. “I saw an opportunity to introduce some of the techniques I learned while working with the biostatistics community at Johns Hopkins. This may be the first time a publicly available tool has been used to directly link travel survey data to methods for estimating health benefits.”
The HOT model has been made available online to the public with instructions and documentation, and Younkin hopes it will be used by researchers, students and decision-makers to help bring health into transportation policy. GHI’s Henry Fremont, a co-author of the paper, has developed a web application that allows easy access to the HOT model to an even wider audience than the software package itself that’s available here. The HOT model package and package tutorial are also online. Questions can be directed to Younkin at firstname.lastname@example.org.
By Ann Grauvogl/March 9, 2022