The Centers for Disease Control recommends about 21 minutes of moderate physical activity each day, yet most Americans fall far short, with only one in four meeting age-specific physical activity targets. This lack of activity contributes $117 billion to our overall healthcare costs and accounts for 8.3% of deaths among U.S. adults. With the incoming administration taking a renewed aim at the root causes of chronic conditions like obesity, it would be worth considering the impact of transportation and land use decisions as a way to make America healthier.
Public transit naturally promotes physical activity, as it typically requires some walking or biking to and from stops. Many riders will walk about ¼ mile ( five minutes) to reach a bus stop and may walk even further for faster services like trains. Over the course of a day, a transit rider could cover ½ to one mile (10 to 20 minutes) on foot as part of their commute. If the average American walked as much as the active transit rider, we can help close the physical activity gap, reduce healthcare costs, and contribute to longer, more productive lives.
In Charlotte, a study of light-rail passengers found that riders could have walked up to 1.2 extra miles per weekday and had an 81% lower chance of being obese over time compared to the control population. The study recommended that the physical activity benefits of transit be included in project funding evaluations—a factor often overlooked in current transit planning.
While walking to and from transit stops has been shown to reduce obesity, each hour spent driving has been linked to a 6% increase in obesity risk. By factoring physical activity benefits into funding decisions for transit and other transportation infrastructure, more people could access transit for their daily travel, gaining the benefits of a moderately more active lifestyle. Expanding transit access near homes and businesses could contribute significantly to public health by making active transportation an easier choice.
In the U.S., federal funding for public transit infrastructure comes from a combination of formula funding and competitive grants. Formula funding mainly supports basic services, such as bus transit in both urban and rural areas. Competitive grants go to specific projects based on their alignment with scoring criteria established by Congress and the Federal Transit Administration (FTA). This analysis focuses on the Capital Improvement Grant (CIG) program, a competitive grant program that funds transit projects with a “fixed guideway.” A fixed guideway typically refers to infrastructure like railroads or subways, where vehicles are restricted to a specific route. However, it can also apply to services such as Bus Rapid Transit (BRT), where buses operate in dedicated lanes, mimicking the function of rail transit while using rubber-tired vehicles.
Scoring for CIG grants includes many factors, some related to project viability but others related to things like environmental impact, congestion relief, local economic development, and land use patterns. Absent from these project considerations are impacts to overall health and the healthcare costs or savings associated with increased transit ridership.
Lessons from abroad
Many peer countries directly account for the health outcomes related to transportation infrastructure as part of their transportation benefit-cost analyses. The United Kingdom and Australia account for physical activity and downstream health outcomes from transportation investments. Both countries measure reductions in national mortality from projects that encourage more walking and cycling as part or all of a trip. By including health and physical fitness impacts in infrastructure planning, these countries can help justify denser neighborhoods and more transit options that lend themselves to more physical activity and make it easier to access employment opportunities.
In the United Kingdom, the Department for Transport (DfT) considers the benefits and risks associated with increased walking and cycling when prioritizing transportation projects. The agency measures any physical activity attributable to a project using the Metabolic Equivalents (MET) hours per week.
According to DfT guidelines, walking is the primary contributor to physical activity across all ages and genders and is often maintained by individuals later in life. While cycling is more vigorous, it currently has a lower mode share compared to walking, and contributes less to current population-level physical activity. Due to this lower baseline, DfT policy suggests greater potential for health benefits from projects that increase cycling. By contrast, transportation projects that encourage door-to-door car travel without promoting physical activity are at a scoring disadvantage in this framework.
In addition to benefits from increased physical activity, DfT accounts for risks to walkers and cyclists associated with vehicle crashes and increased exposure to air pollution. In an aggregation of 17 studies, all but one showed a significant net positive in health-related outcomes from physical activity versus risks from negative factors.
Fig 1. Aggregation of multiple studies indicating net benefits and risks associated with active transportation. Figure adapted from Mueller, Et al., 2015. Health impact assessment of active transportation: A systematic review. Prev. Med. (Baltim). 76, 103–114.
In a practical application of the U.K. project scoring, a 2010 estimate of a typical cycling project showed a £408 benefit from reduced mortality per new cyclist attributable to a project, and £28 benefit from reduced National Health System (NHS) spending per new cyclist. The authors also found that offsetting the cost of a project through health and other monetized benefits requires one new cyclist over the project’s useful life for every £10,000 in project cost.
In Australia, the benefit-cost analysis for transportation projects includes health impacts from mode shifts that lead travelers to walk or bike more. Australia’s approach calculates positive health outcomes for motorists who incorporate walking or cycling as part of their transit use. Conversely, it also considers the negative impact when someone switches from a fully active mode to one that includes riding transit for part of the journey (4.7.1 at p. 32).
Under the Australian model, project benefits include a private health benefit of AU$2.95 per person-kilometer walked and an external health system benefit of AU$1.44 per person-kilometer walked. Similar calculations apply to cycling, with a private benefit of AU$1.48 and an external health benefit of AU$0.72 per person-kilometer cycled.
For example, a 2016 project to close a gap in an off-street multiuse path showed an AU$204,000 net present value (NPV) over the project life cycle. The project’s gross present value benefits were AU$1.8 million, including AU$484,000 from health system benefits related to increased walking and cycling. Health system benefits for the project scored higher than road decongestion (AU$107,000), environmental benefits (AU$24,000), and expected maintenance costs (AU$58,000). Without accounting for health system benefits, the project’s positive NPV score would have been negative (-AU$280,000).
Policies promoting transit investments within active-travel distances from residential areas have significantly increased transit accessibility in both the UK and Australia. In the UK, 95.6% of residents live within 1,000 meters (0.62 miles) of high-capacity transit, while in Australia, the figure stands at 83.5%. By comparison, only 58.9% of urban residents in the U.S. enjoy similar access, underscoring a substantial gap in transit accessibility.
Implications for U.S. policymakers
Experience from abroad suggests that incorporating transit’s positive impacts on health, economic mobility, and economic growth into the evaluation of transportation infrastructure projects motivates planners to deliver high-quality service to more people. This approach moves beyond the current “box-checking” approach, which often lacks a strong connection to service quality. Additionally, these examples also highlight the importance of designing land-use patterns around transit stops to include adequate housing and businesses within walking and cycling distance, ensuring tangible community benefits.
Rather than adding yet another scoring metric to the FTA’s transit grant rating criteria, which could dilute its effectiveness, the evaluation process should be simplified. Public transit ridership naturally encourages active commuting, resulting in better health outcomes compared to driving. However, merely including health outcomes as an additional factor in transit capital grant applications is unlikely to yield meaningful improvements.
The FTA’s current scoring guidelines undervalue supportive land use near transit stations. While recent adjustments consider the proportion of restricted affordable housing near stations, they overlook a critical factor: the overall quantity of housing near transit.
Prioritizing transit ridership while accounting for its positive health impacts–ranging from increased physical activity to reduced vehicle crashes to economic mobility to economic growth–can motivate project planners to optimize around those factors. This approach will provide the best service to the most people, moving beyond the current box-checking process, which only loosely reflects actual service quality.
This will also encourage project planners to collaborate with land-use regulators to increase the number of homes and businesses within walking distance of transit stations. Even a modest 10% increase in residential density near transit stations can boost ridership by 7%. Scaling this strategy could dramatically enhance overall transit ridership and improve the financial viability of regional transit networks, while promoting active transportation for both transit users and non-users.
We should reconsider how proposed transit projects are evaluated, placing greater emphasis on increasing ridership rather than adhering strictly to current FTA scoring criteria. Adopting practices from the U.K. and Australia would provide a more comprehensive framework, better accounting for the effects of transportation infrastructure on physical activity, public health, and the financial performance of public transit investments, offering a more effective alternative to the status quo.