The Great Urban Outdoors: Good for our Health?

Summertime is such a great time to be out and about. It’s warm, often sunny, and greenness and lushness abound. Flowers, fresh produce, trees, grasses—everything is busting out in full glory. I know, I know, it’s August 9, and summer is almost… uh… over.

But let’s not think about that right now.

As I was saying—summer is a prime time to be out in nature, swimming, walking, climbing, biking, camping, sitting, etc. And science tells us that contact with nature is good for us; it’s been shown to boost mood, reduce production of stress hormones. increase pain tolerance and now, we find it can even reduce our tendencies for negative thinking. A recent New York Times article by Gretchen Reynolds focused on a study investigating how being in nature affects our brain function so to improve mood. In short, taking a walk for 90 minutes can help keep us from brooding.

No, I don’t mean this.

I mean this.

Here’s more from the article about brooding:

Brooding, which is known among cognitive scientists as morbid rumination, is a mental state familiar to most of us, in which we can’t seem to stop chewing over the ways in which things are wrong with ourselves and our lives. This broken-record fretting is not healthy or helpful. It can be a precursor to depression and is disproportionately common among city dwellers compared with people living outside urban areas, studies show.

Leaving aside a lot of the interesting neurophysiological detail (which you can find in the article) the researchers decided to test the effects of nature on brooding.

…The scientists randomly assigned half of the volunteers to walk for 90 minutes through a leafy, quiet, parklike portion of the Stanford campus or next to a loud, hectic, multi-lane highway in Palo Alto. The volunteers were not allowed to have companions or listen to music. They were allowed to walk at their own pace.

Immediately after completing their walks, the volunteers returned to the lab and repeated both the questionnaire and the brain scan.

As might have been expected, walking along the highway had not soothed people’s minds… their broodiness scores were unchanged.

But the volunteers who had strolled along the quiet, tree-lined paths showed slight but meaningful improvements in their mental health, according to their scores on the questionnaire. They were not dwelling on the negative aspects of their lives as much as they had been before the walk.

…These results “strongly suggest that getting out into natural environments” could be an easy and almost immediate way to improve moods for city dwellers, Mr. Bratman said.

Cool, huh? And not surprising. Our bloggers have written lots about the benefits of trips to nature, including here.   In Japan, the term forest-bathing  or shinrin-yoku, is used to refer to spending time outside in green spaces in order to get stress-reduction-related health benefits. There’s more info about it here.

But it does leave us with a question: what counts as nature for brooding-reduction purposes? I’m wondering because this year I’ve done a fair amount of urban and suburban adventuring outdoors—on a bike, on foot, on skis and in a kayak.  On Tuesday I went kayaking with my friend Janet and her sister in the Charles River basin. Here’s where we rented our kayaks:

This is a very urban and industrial (albeit watery) area. You launch the boat in a side canal, go under a rusty old bridge, and pop out in the Charles River basin, next to the Longfellow bridge, which is under construction. There’s a lot of activity, with a barge, lots of floating orange barriers, noise, and the sparks of welding going on. I didn’t take photos myself on this trip (didn’t want to tempt the fates by taking out my phone), but here’s an older photo I found online that gives you an idea of what it’s like:

In addition to navigating this steely industrial landscape, there were also the ubiquitous-in-summer duck boats trolling around. Here’s a lovely photo of one of them:

Actually, the photo above is misleading, as there were in fact loads of them all over the place, so we had to keep watch for them and try to stay out of the way. Of course, we had a great time, enjoying a picnic lunch on the Esplanade park area along the river in Boston, then getting back in the boats to return to the canal docks.  We did, however, make a quick detour to the local mall before returning.  I didn’t get out of the boat, but here’s proof I was there:

But the question remains: does urban nature provide those coveted mental health benefits? How many trees do I have to see, how verdant does it have to be in order to chill us out?

This may seem like a silly or pedantic question (and as a philosopher, I embrace both), but it could have real consequences for public health. If we know that some amount of green space in urban areas confers real benefits on populations (like lowered blood pressure, cortisol, pulse rate, etc.), then this would give us reason to fund more public green spaces and offer more nature programs in cities. There are lots of reasons to do this anyway, but here’s one more: it may be good for our health. We don’t know enough yet about the interaction between urban space and green space, which is worth pursuing. In the meantime, I’ll keep a healthy dose of urban outdoorsiness in my activity diet.