For children today, time spent outdoors is becoming more of a luxury—or in some cases, a chore—than a staple. In recent years "nature deficit disorder" among kids has evolved from a turn of phrase to a cultural indictment.[2,3] Smartphones and other screens are increasingly vying for kids' attention, but blame lies elsewhere, too: just as recess is being reduced or phased out in many schools, children's activities are being increasingly structured and scheduled, and concerns over neighborhood crime and safety can impede their ability to play freely outdoors. A 2013 study by the U.S. Centers for Disease Control and Prevention found that nearly three-quarters of high-school students had less than one hour of physical activity per day, while childhood obesity rates are trending steadily upward.
Almost at the same time, researchers have dramatically expanded their understanding of the positive link between health and parks of all sorts—from the most majestic national parks to regional community parks and urban "pocket parks" with just a swing set or a few benches. They have also begun to disentangle some of the many pathways through which these benefits appear to occur.[8–13] That knowledge is giving rise to a nationwide movement to integrate park visits into disease treatment and prevention through "park prescription" programs.
In some cases, the programs have received support from the Healthy Parks Healthy People initiative of the National Park Service (NPS), launched as a pilot in 2011 and set to expand significantly in 2016 and beyond. The Healthy Parks Healthy People program aims to improve health through regular use and enjoyment of parks and public lands nationwide, says Sara Newman, director of the NPS Office of Public Health. The NPS is also participating in the White House's Every Kid in a Park initiative, launched in September 2015. This program provides fourth-graders and their families free admission to national parks and other federal lands and waters for a full year, and transportation support to schools that need it.
Other park-prescription programs are locally managed and operated, including a growing number organized around urban trails and other nontraditional "linear" parks that promote nonmotorized transport.
Current evidence suggests that children have much to gain from time spent outdoors and much to lose from a lack of park access.[17,18] In addition to myriad health benefits offered by physical activity in general, research has shown that outdoor exercise in nature can enhance emotional well-being and amplify the benefits of physical exercise.[19,20] And for kids in particular, being in or near green spaces has been found to be associated with better test scores, improved self-discipline and cognition,[23,24] and reduced behavioral problems and symptoms of attention-deficit/hyperactivity disorder (ADHD).[25–28]
Several studies suggest that spending time outdoors can protect against myopia (nearsightedness).[29,30,31,32] Still other research indicates that neighborhood green space may help mitigate income-related health disparities.
Parks and green spaces also may contribute to population health by reducing exposures to air pollution and noise, capturing and filtering stormwater runoff, and mitigating heat-related illnesses. These benefits make urban parks an important tool in climate change adaptation, says Payam Dadvand, a researcher and assistant professor at the Centre for Research in Environmental Epidemiology (CREAL) in Barcelona.
Eventually, current trends could lead parks straight to the core of the American healthcare system, says Kristin Wheeler, associate director of the Institute at the Golden Gate, a nonprofit partner of the NPS. Someday patients could be incentivized through their insurance to be active outdoors, she suggests, similar to existing small-scale programs that offer financial benefits for exercise and other healthy activities.[39,40]
"This is the way that nature and parks are going to be talked about—it's going to be commonplace for your doctor to ask you about how much time you've spent in nature," Wheeler says. "It's this perfect culmination, where everybody's starting to see this as the wave of the future."
Environ Health Perspect. 2015;123(10):A254 © 2015 National Institute of Environmental Health Sciences