What are some ways to be more productive in shorter amounts of time? originally appeared on Quora - the knowledge sharing network where compelling questions are answered by people with unique insights.

We tend to think that if we power through, sit at our desks until we're done--whatever that is--we'll do better work. I've fallen into this trap myself so many times. And what we end up doing is actually being less productive and less efficient. We get tired, it takes us longer to finish something, we can no longer think clearly, and we make mistakes.

But neuroscience is now showing us there's a much better way, even though it goes against everything our work-devoted culture expects us to do. Research shows that we should work in shorter sprints. And for knowledge workers, don't expect to be able to work more than four-to-six good hours a day.

Why? Well, the eight-hour work day is based on studies that Henry Ford undertook in the 1920s. He wanted to know how far you could push manual laborers before they got too tired to function. The answer was eight hours, five days a week. (We have unions and Henry Ford to thank for the two-day weekend.)

For knowledge workers, we don't really know how far you can push people until they become an unproductive butt in the chair. (But we'll reward them anyway! Our face-time cultures tend to reward those butts-in-chairs in the office late at night, thinking they're "devoted" workers, rather than the unproductive and stupid time wasters they are. And I've been one of them, so I know!) Economists have found that you can push someone to work 60-plus hours a week for a short period. But after a few weeks, you lose any productivity gains, and you would have been better off sticking to a consistent 40-hour work week. They've found "productivity cliffs" that hit right around 55 hours a week and fall steeply with each additional hour overworked.

What neuroscience is showing us is that we have 90-minute attentiveness cycles during the day, just as we have 90-minute sleep cycles at night. We also know our brains are constantly looking for novelty, and they get bored easily, which is why it can be so difficult to concentrate, and why the ding of that Facebook notification or new email seems so instantly appealing.

We also know that when we take breaks, go for a walk, or even make time to daydream, our brains are actually more active, refreshed, and primed for insight. During those breaks, our brains are also incubating--they continue unconsciously to work on problems for us.

So, the best practice from neuroscience is to think of working in 90-minute sprints, and then taking a break. Go for a walk outside. Your brain, and your quality of work, will thank you.

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