Go for a walk

Updated July 2015:

Open Culture has an article on the value of walking. It is based on the research on the same people in this 2014 post so it fits best here but is good as a reminder for me.

Oppezzo and Schwartz speculate that “future studies would likely determine a complex pathway that extends from the physical act of walking to physiological changes to the cognitive control of imagination.” They recognize that this discovery must also account for such variables as when one walks, and—as so many notable walkers have stressed—where. Researchers at the University of Michigan have approached the where question in a paper titled “The Cognitive Benefits of Interacting with Nature” that documents a study in which, writes Jabr, “students who ambled through an arboretum improved their performance on a memory test more than students who walked along city streets.”

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This makes intuitive sense but it is nice to see the numbers that back the idea up.

Walks make you more creative.

While Oppezzo and Schwartz didn't test for the mechanism behind why walking leads to more ideas — that's for another study — they did form a few hypotheses. It might be that walking takes a fair amount of attention, so you don't have as much mental energy available to filter out uncommon ideas. It might also be that walking lets you make broader associations or spreads your area of focus. How to walk more

Courtesy of the American Psychological Association.People who went for walks had more original thoughts.
Thankfully for us office workers, the positive effects of the walk aren't reliant on trotting around an idyllic California campus: The Stanford researchers found the same creativity-inducing effects when people walked on a treadmill in a dark, windowless room.
So even if you're stuck in a cubicle, you can insert walks into your workday. 

My hero Darwin knew the value of a good walk.  The story was, he would get so involved in his thoughts that he deliberately left a set of pine cones on the path and would knock one away with each lap.  His mischievous children would sometimes replace them so he would walk further.