Selected as the #1 book in diet/exercise for 2015 by USA Best Book Awards.

We start out with the best intentions. We're going to exercise more and get in shape Then five days a week at the gym turns into two... then becomes none. We hit the snooze button and skip the morning run.

We really do want to be healthy and fit, but we're over whelmed and overextended--and exercise feels like another chore to complete. Is it any wonder we don't stick with it?

Behavior expert Michelle Segar has devoted her career to the science of motivation. In No...