natural settings. Tyrväinen wanted to drill deeper into the data, so for
another study, her team took 82 office workers, mostly women, to
each of the three different sites: city center, manicured park and
forest park. At each place, before and after sitting for fifteen minutes
and then after walking leisurely for thirty minutes, the researchers
collected questionnaires, saliva samples, blood-pressure and heart-
rate data. Throughout, the volunteers were instructed not to speak to
each other (to eliminate the positive psychological benefits of
socializing). If people felt happy, it would not be from making
friends.
The results turned out to be what scientists call beautiful. There
were significant effects and linear dose responses that followed
predictions. Compared to sitting in the van, the volunteers did not feel
psychologically “restored” in the city, but they did in the park and
forest. They experienced these changes relatively quickly, after just
fifteen minutes of sitting outside. After the short walk, these
restorative feelings continued to increase. The more time people spent
in the green areas, the better they reported feeling, and the effects
were slightly stronger for those in the wilder forest. But the benefits
weren’t just about relaxation; on measures of vitality, which you’d
think might rise in the city, only nature did the trick, although it took
the full forty-five minutes. Both the vitality and restoration scores
dropped in the city, to the point where participants in the park or
forest felt 20 percent better than their urban peers. The greenies also
felt stronger positive emotions and lower negative emotions, and the
respondents reported feeling more creative. On the objective
measures, cortisol levels dropped in all three settings, perhaps a result
of being away from work demands, speculated Tyrväinen.
The good news for city dwellers is that just fifteen to forty-five
minutes in a city park, even one with pavement, crowds and some
street noise, were enough to improve mood, vitality and feelings of
restoration.