“Our brains were built for walking,” says John Medina in Brain Rules — at the tune of 12 miles per day. Numerous studies have demonstrated that exercise is good for the body... and for the brain. The prefrontal cortex and medial temporal cortex control thinking and memory have greater volume in people who exercise.
Though a great deal of our evolutionary history remains shrouded in controversy, the one fact that every paleoanthropologist on the planet accepts can be summarized in two words: we moved. A lot.
As soon as our Homo erectus ancestors evolved, about 2 million years ago, they started moving out of town. Our direct ancestors, Homo sapiens, rapidly did the same thing.
Because bountiful rainforests began to shrink, collapsing the local food supply, our ancestors were forced to scamper up and dine out. Instead of moving up, down, and across complex arboreal environments, which required a lot of dexterity, we began walking back and forth across arid savannahs, which required a lot of stamina.
Homo sapiens started in Africa and then took a victory lap around the rest of the world. The speed of the migration is uncertain; the number changes as we find new physical evidence of habitation and as we're better able to isolate and characterize ancient DNA.
Anthropologists can say that our ancestors moved fast and they moved far. Males may have walked and run 10 to 30 kilometers a day, says anthropologist Richard Wragham. The estimate for females is half that. Up to 12 miles.
12 miles is the distance scientists estimate we moved in a day, every day. The terrain was unpredictable, people needed to steer clear of dangers, be ready for any kind of encounter, and navigate their way out of rough spots without a GPS.
Moving helped stay alert and fit, given our physical evolutionary disadvantages — no fangs, little body hair, and so on. What we did have was our brain and the cognitive skills that came with it, which developed on the go, literally.
Scientists have conducted extensive research on the positive effects of exercise on aging populations. Movement gets blood to our brain, which brings glucose for energy and oxygen to absorb the toxic electrons left over from the process, and stimulates the protein that keeps neutrons connecting. This is what keeps people active in their later years.
Medina refers to a conversation between renown architect Frank Lloyd Wright and journalist Mike Wallace:
Wallace: “When I walk into St. Patrick's Cathedral... here in New York City, I'm enveloped in a feeling of reverence.”
Wright: “Sure it isn't an inferiority complex?”
Wallace: “Just because the building is big and I'm small, you mean?”
Wallace: “I think not.”
Wright: “I hope not.”
Wallace: “You feel nothing when you go into St. Patrick's?”
Wright: “Regret... because it isn't the thing that really represents the spirit of independence and the sovereignty of the individual which I feel should be represented in our edifices devoted to culture.”
This is a deep observation that takes the conversation to a new place rather than just going along with the common comment. In a separate occasion, Wright said, “the truth is more important than the facts.” And so is an agile mind filled with curiosity and imagination.
The difference in the aging process of someone like Wright who stay active in his later years and someone who conducts a more sedentary life is stark. Scientists found that an active lifestyle enhances aging — people who move more, reduce the risk of cardiovascular diseases.
Movement elevates cognitive performance — improving the ability to reason quickly, think abstractly, and improvise building off knowledge to solve problems. Four months of exercise can help sedentary people get back online, so to speak. Walking several times a week is sufficient, a strengthening regimen expands those benefits.
We do some of our best thinking with our whole bodies, not just the head. Steve Jobs was a fan of walking meetings, and so is Mark Zuckerberg, and it's easy to see why they would be comfortable with talking while walking side by side with someone. That is the body position men prefer when in conversation based on how their brains process information.
I've been experimenting with walking meetings for a while and I find them reinvigorating. Going outside gets us out of the same old environment, and if we plan well by going to a park or a walking trail, we come into contact with nature, which gets our creative juices going and has a calming effect on us. Walking is also an equalizer, people side by side tend to have a better focus on issues rather than at the other person.
We should get out more, move around, experience being side by side with others, and let our imagination soar.