When: The Scientific Secrets of Perfect Timing

by Daniel H. Pink

When we wake up, our body temperature slowly rises. That rising temperature gradually boosts our energy level and alertness—and that, in turn, enhances our executive functioning, our ability to concentrate, and our powers of deduction.

those sharp-minded analytic capacities peak in the late morning or around noon.

Human beings don’t all experience a day in precisely the same way. Each of us has a “chronotype”—a

In short, all of us experience the day in three stages—a peak, a trough, and a rebound. And about three-quarters of us (larks and third birds) experience it in that order. But about one in four people, those whose genes or age make them night owls, experience the day in something closer to the reverse order—recovery, trough, peak.

About 62 percent of the creators followed the peak-trough-recovery pattern, where serious heads-down work happened in the morning followed by not much work at all, and then a shorter burst of less taxing work.

we wake up mildly dehydrated. Throw back a glass of water first thing to rehydrate, control early morning hunger pangs, and help you wake up.

Don’t drink coffee immediately after you wake up.

Soak up the morning sun. If you feel sluggish in the morning, get as much sunlight as you can. The sun, unlike most lightbulbs, emits light that covers a wide swath of the color spectrum.

your brain to stop producing sleep hormones and start producing alertness hormones.

vigilance breaks”—brief pauses before high-stakes encounters to review instructions and guard against error.

And the wider phenomenon—that breaks can often mitigate the trough—likely applies “in other important sequential decisions or judgments, such as legislative decisions . . . financial decisions, and university admissions decisions.”

simply standing up and walking around for five minutes every hour during the workday can be potent.

five-minute walking breaks boosted energy levels, sharpened focus, and “improved mood throughout the day and reduced feelings of fatigue in the late afternoon.”

more effective than a single thirty-minute w...

Regular short walking breaks in the workplace also increase motivation and concentration and enhance creativity.21

with coworkers about something other than work—are more effective at reducing stress and improving mood than either cognitive breaks (answering e-mail) or nutrition breaks (getting a snack).

relaxation breaks (stretching or daydreaming) eased stress and boosted mood in a way that multitasking breaks did not.27 Tech-free breaks also “increase vigor and reduce emotional exhaustion.”

The non–desk lunchers were better able to contend with workplace stress and showed less exhaustion and greater vigor not just during the remainder of the day but also a full one year later.

The most powerful lunch breaks have two key ingredients—autonomy and detachment. Autonomy—exercising some control over what you do, how you do it, when you do it, and whom you do it with—is critical for high performance, especially on complex tasks.

Detachment—both psychological and physical—is also critical. Staying focused on work during lunch, or even using one’s phone for social media, can intensify fatigue, according to multiple studies, but shifting one’s focus away from the office has the opposite effect.

boosts short-term memory as well as associative memory, the type of memory that allows us to match a face to a name.

Napping even increases “flow,” that profoundly powerful source of engagement and creativity.48

Napping strengthens our immune system.50 And one British study found that simply anticipating a nap can reduce blood pressure.51

five-minute naps did little to reduce fatigue, increase vigor, or sharpen thinking. But ten-minute naps had positive effects that lasted nearly three hours.

once the nap lasted beyond about the twenty-minute mark, our body and brain began to pay a price.52 That price is known as “sleep inertia”—the confused, boggy feeling I typically had upon waking.

with naps of more than an hour, cognitive functioning drops for even longer before it reaches a prenap state and eventually turns positive.

Koran, which a thousand years ago identified sleep stages that align with modern science, also calls for a midday break.

The Mayo Clinic says that the best time for a nap is between 2 p.m. and 3 p.m.1 But if you want to be more precise, take a week to chart your afternoon mood and energy levels, as described here.