From Six Ingredients for a Good Life by Tony Schwartz.
We live in a world in which we’re forever juggling demands, but rarely focusing on any one thing for long.Absorbed attention — the capacity to delay other gratifications to focus on one thing at a time — is the sine qua non of achieving and sustaining excellence at anything. Unlike machines, however, human beings aren’t meant to operate at the highest intensity for very long. Instead, we’re designed to pulse between spending and renewing energy approximately every 90 minutes. It’s not the hours you work that determine the value you generate, but rather the energy you bring to whatever hours you work. The more skillfully you renew, the more energy you’ll have. I wrote The Way We’re Working Isn’t Working in three uninterrupted 90 minute “sprints” every morning — each one followed by a relatively short period of real renewal, ranging from deep breathing, to eating something, to taking a run. It was a time for both restoration and reflection. I finished the book in half the number of hours than I had any previous book, when I worked ten to 12 hour days. The world’s best performers — musicians, chess players, athletes — typically practice the same way: for no longer than 4 ½ hours a day. They also sleep more than the rest of us, and take more naps. These great performers figured out that when they push for too long, their attention wanders, their energy flags, and their work suffers. But because they’re so focused when they are working, they get more done, in less time.
Even at the low level I operate at, I’m finding the principles of this increasingly true in my own life and ministry.