A Cost-Benefit Analysis of Physical Activity Using Bike/Pedestrian Trails
Trails in Lincoln, Nebraska have the potential to generate large benefits for trail users in terms of avoided medical costs. These benefits may significantly outweigh the per capita cost of trail construction and maintenance. However, due to simplifying assumptions made regarding both benefits and costs, the cost-benefit ratios are unreliable.
This study is an interesting example of a simple approach to cost-benefit analyses comparing the medical benefits of physical activity to trail investment using relatively easily available data. However, due to some oversimplified assumptions, it is likely the benefits per dollar of trail investment are significantly overstated. The authors assume that all trail users reach physical activity goals using the trails and would not have reached their activity goals without the trails. Both assumptions bias the benefits upwards. Related to costs, the authors assume trail users are the only ones who have to pay, which biases the cost per person upward, as the trails were publically financed. Although both cost and benefits per trail user were biased upward, the benefits are likely more overinflated, thus biasing the cost-benefit ratios upward significantly.
This study was based in Lincoln, Nebraska, which had a population of 272,996 in 2014.
The study compared five cycling and pedestrian trails in the city, ranging in length from 1.6 to 4.6 miles. Four of the trails are concrete and one is limestone chip.
The purpose of this study is to provide an economic argument for trails as a public health intervention by comparing the cost of trail construction and maintenance to the reduced medical expenses of those who use the trail.
This is a peer-reviewed study conducted by staff with the Centers for Disease Control and Prevention and the Nebraska Health and Human Services System. It is not clear whether there were other funding agencies.
- Each year, the average trail user has $564.41 in benefits from reduced medical care due to increased physical activity.
- Each year, across the five trails studies, trail maintenance costs an average of $4,314 per mile, ranging from $3,329 to $5,692.
- Initial trail construction cost an average of $12,555 per mile, ranging from $708 to $19,855.
- Assuming the annualized trail construction and maintenance costs are borne by trail users only, and trail users would otherwise not be physically active, every $1 investment in trails is associated with $2.94 in benefits.
The authors measure benefits of physical activity as the difference between average medical expenditures for active versus inactive persons, using national expenditure data from the National Medical Expenditure Survey. They define “active” as persons who get at least 30 minutes of moderate or strenuous physical activity per week and assume all trail users are on the trail three times per week, every week of the year.
The authors used an existing trail study conducted in 1998 for data on average daily trail use and annual construction and maintenance costs. Costs per user were calculated as annualized construction and maintenance costs, divided by the estimated number of people using the trail.
Wang, G., C.A. Macera, B. Scudder-Soucie, T. Schmid, M. Pratt, and D. Buchner. 2005. “A cost-benefit analysis of physical activity using bike/pedestrian trails.” Health Promotion Practice 6: 174-179.