Jamie Ducharme, Time, "Why is it so tough to get people to do something so good for and accessible to them? Physical limitations and health problems are certainly a factor for many people. Modern life deserves much of the blame, too, with long, sedentary work days and infrastructure that often makes it easier to hop in the car than walk or bike somewhere. But research suggests there’s another obstacle that affects all of us: our brains don’t want us to exercise."