Walking is tied to a number of health benefits and should (almost) always be encouraged. That is why we created a pedometer app to track steps. However, anecdotally, many of us would agree that walking in a natural environment is generally a more pleasant experience than other walking. From my own experience in walking in cities and towns across four continents and natural environments across five continents, I can relate to Henry David Thoreau who said “I think that I cannot preserve my health and spirits, unless I spend four hours a day at least – and it is commonly more than that – sauntering through the woods and over the hills and fields, absolutely free from all worldly engagements.” even though I myself don’t walk four hours a day in any environment, let alone walk in nature for four hours.
Given anecdotal experience with walking in nature, it is interesting to see that medical science can now use data to explain the neurological mechanisms of how walking in nature helps the brain. A Stanford study establishes that cerebral blood flow and neural activity in the subgenual prefrontal cortex (sgPFC) is decreased for nature walkers and not for urban walkers. Self-reporting from the walkers also showed that nature walkers ruminated less. I first heard about this study from a column that explains the Stanford study for a wider audience
The sgPFC (or Brodmann Area 25, BA25) plays a major role in depression and decreased neural activity in this area can help prevent depression and combat stress. Since walking in nature helps the brain (specifically the BA25 region) and decreased rumination/brooding helps reduce stress, the results of the Stanford study strongly suggest that walking in nature can change the brain in ways that help mental health, improve mood and reduce the chances of depression.
Clearly, walking in nature is not a viable option for all people in all circumstances. Health conditions, weather conditions or concerns about some wild animals, criminal humans etc. may dissuade some people from walking in nature. However, for those who enjoy walking in nature and for those who’d like to consider it, studies seem to establish that walking in nature can impact the subgenual prefrontal cortex in ways that are good for the brain.