Joe McConaughy optimism > psychologists have a technical term for it: cognitive reappraisal Appreciation and gratitude have a long list of research-backed benefits. People who make a point to notice the things they're grateful for are happier, take better care of their health, feel less aggression, and even make friends more easily. the Appalachian Trail, which in his book A Walk in the Woods author Bill Bryson appropriately calls “the grandaddy of long hikes,” spans 2,190 miles. This means Meltzer averaged over 47 miles of hiking a day for 45 days straight. And these aren’t just any miles; these are hilly miles.