Urban parks and trails are cost-effective ways to promote exercise

A new systematic review in the American Journal of Health Promotion finds that providing public parks and walking and biking trails is the most cost-effective strategy to increase physical activity among large populations in urban areas.

Virpi Kuvja-Kollner, lead author of the review, noted that although public budgets for health care and other services are tighter than ever, the most cost-effective approach to increase physical activity among large urban populations is to make changes to the structural environment. Creation of more outdoor exercise opportunities, such as "pedestrian or bicycle trails en route to public transportation stations or providing public parks in densely populated areas," can require a substantial public investment but have long life spans.

"The main focus in promoting physical activity should be to get people who are not active to get moving instead of just promoting more exercise to those who are already active," added Kuvja-Kollner, a researcher/instructor and doctoral candidate at the University of Eastern Finland.

Between May and August 2013, the researchers searched 2,058 articles relating to physical activity among wide population groups, using ten that met the criteria for this review. Their analysis found that physical activity for large population groups was more effective in terms of both costs and effects when people used public spaces for exercise.

To determine cost-effectiveness, the researchers divided the per-person, per-day costs of different types of interventions by the number of physical activity hours gained. "There was a huge variation in the efficiency of the interventions," the study noted. "The most inefficient intervention cost almost 400 times more... than the most efficient intervention."

Tracy Flood, M.D., Ph.D., director of data for statewide obesity prevention at the University of Wisconsin School of Medicine and Public Health, agreed with the review's findings that community structural improvements can increase physical activity. But Flood cautioned that this may challenge individual beliefs that being physically active requires equipment like gym shoes, a sports bag and the willpower to step onto a treadmill at 5 a.m..

"Studies examining cost effectiveness are limited and more studies are needed," Flood added. "This is important because budgetary considerations are a very real part of all community improvement. Having more data on cost-effectiveness would allow for more informed decision-making and buy-in at the county or city level."

"Research in how public spaces impact our health is growing. The 'What Works for Health' website created by the University of Wisconsin outlines many population-based strategies that have been found to be effective," Flood said. "At this point the evidence has accumulated so much that we are no longer looking at one or two studies, but dozens of studies summarized in multiple reviews. Evidence is growing that improving where we live will impact our health."

Kuvaja-Kollner said she hopes this study draws attention from community planners. "They should take into account promoting physical activity by combining walking and hiking trails near public transportation."