A systematic review of 11 controlled studies that included 833 study subjects concluded that exercising outdoors offers significant benefits for the body and the mind.  Relative to indoor exercise, being physically active in a natural environment was associated with numerous advantages including a greater lift in mood, stronger feelings of revitalization, better clarity of thought, and less tension and anger. Study subjects also reported greater pleasure and satisfaction with outside exercise and a stronger commitment to repeat the activity in the near future.

Based on the studies I have reviewed, along with the fact that our hunter-gatherer ancestors spent most of their waking day in the outdoors, I am convinced we are “hard-wired” to

require regular exposure to nature. Bottom line – look for every opportunity to move your body in the great outdoors. I strive to do it every day. (Environmental Science and Technology, Feb 2011)