At work, a calendar filled with meetings and deadlines often dictates the cadence of our days. But despite what tightly timed agendas might try to insist, our internal body clocks are secretly running the show. Scientists call this personalised daily pattern of sleep and wakefulness a circadian rhythm.

Whether you know it or not, our bodies have a specifically set programming schedule for the best time of day to concentrate, spark new ideas, and experience peak performance.

Scientists have tracked how cognitive abilities rise and fall, and found that most of our brains follow a neatly predictable pattern of cognition that fluctuates hour by hour, throughout the course of a day.

Author Daniel Pink revealed his formula for a perfect science-backed workday in his 2018 New York Times bestseller "When: The Scientific Secrets of Perfect Timing."

The strategy for your own perfect day might differ from this, depending on whether you're more of an early riser or a night owl, but in his book Pink reveals a basic formula for a better work schedule, whatever time of day you tend to plug in. We've added in a few other science-backed ways to make your workday better, too.

Take a look.

Almost all of us fall into a predictable mood pattern each morning.

Scientists who studied 509 million tweets from 2.4 million people in 84 countries around the world found that just about everyone's mood follows a body-clock-linked daily rhythm.

Our attitudes brighten in the morning.

As we wake, we become happier, warmer and enjoy work more. The good feeling typically peaks somewhere around noon. So it might be best to schedule important meetings and earnings calls during these happier morning hours.

Researchers who studied more than 26,500 earnings calls in the US from 2001 to 2007 found that, generally, the tone of an earnings call became more negative as the workday wore on.

Just moving an 8 am earnings call to a 3 pm slot could translate "to abnormal returns of − 1.5 percent a year," on average, a Harvard Business Review report said.

You're likely better at keeping distractions at bay in the morning.

For most of us, "sharp-minded analytic capacities peak in the late morning or around noon," Pink writes in his book.

Scientists who've studied this effect have shown that speed and accuracy at completing tasks are both better in the morning, and that the ability to remain alert tracks closely with sleep and wake schedules, which tend to peak twice a day: once in the late morning, and then again in the evening.

If you're taking a break from work and going to the doctor, you might want to make it a morning appointment.

Studies show that's when caregivers are more likely to wash their hands and diagnose more problems.

Hospital workers don't wash their hands the same way all day long. In his book, Pink references a study of 4,157 caregivers in 35 US hospitals, some of whom washed their hands 38 p percent less often at the end of a shift.

"That is, for every ten times they washed their hands in the morning, they did so only six times in the afternoon," Pink wrote.

Caregivers are not just washing their hands less as the day wears on. Studies suggest doctors are also better at diagnosing colon problems in the morning and have more successful surgeries at that time, too.

(Fortunately, research also suggests nurses who take 10-minute breaks and surgery teams who pause before high-stakes medical maneuvers can help mediate the effects of an afternoon-care slump.)

Your stress-hormone levels also tend to be higher right after you wake up in the morning — putting the body on high alert — so it's a good time to soak in the advice of others.

Pink suggests you might even want to schedule therapy and psychiatry appointments at this time, since you're more likely to absorb suggestions.

Scientists have found that cortisol (stress-hormone) levels tend to spike around 50 percent within half an hour of waking up, putting the body on alert.

Do any critical analyses in the morning, when your powers of logic and deduction are also at their sharpest.

One early study of sleep and wake patterns from 1975 found that people's capacity for logical reasoning generally rises from around 8 am to 2 pm, then falls off.

More recent research suggests that any biological schedule can get wonky in the face of sleep deprivation.

The morning boost doesn't hold true for everyone, though:Scientists have found there are both morning and evening brains.

Morning is generally not a great time for more simple tasks, however.

Keep the email-checking, online shopping, and errand-running to a minimum. Instead, you might want to do more of those mundane chores in the afternoon.

"Alertness and energy levels, which climb in the morning and reach their apex around noon, tend to plummet during the afternoons," Pink writes, citing French psychologist Simon Folkard. Fill the time with easier tasks.

Afternoon drowsiness is no small thing. The effects of an afternoon slump can be as strong as a stiff drink.

Pink cites Neuroscientist Russell Foster on this, who says the biological clocks that dictate our daily schedules are innate and hard-wired.

Take a lunch break at some point.

It's especially important for people in jobs with high emotional or cognitive loads, according to Pink.

Not all good work gets done in the morning. The so-called afternoon slump is actually a great time to solve problems that rely on insight and creativity.

The same body clock forces that guard against distractions and keep us sharp in the morning hours tend to also ward off fresh ideas and innovations.

"At those looser moments, a few distractions can help us spot connections we might have missed when our filters were tighter," Pink wrote in the book.

So go ahead and get those creative juices flowing in the afternoon. But If you need to keep computing and doing more vigilant cognitive work in the afternoon, adding in a few well-scheduled breaks can help keep you going.

If possible, take a pause with colleagues whose company you enjoy.

"Research in South Korean workplaces shows that social breaks – talking with coworkers about something other than work – are more effective at reducing stress and improving mood" than checking email or getting a snack alone, Pink says.

Or get outside.

A breath of fresh air can not only improve your mood but it can also help boost memory and improve focus.

The worst time of day for your brain tends to come crashing in around 2 or 3. During this rough patch, you may want to recharge with a little coffee and then a 20-minute power nap.

Pink calls this a "nappuccino," and says as long as you keep it to 20 minutes or less, you won't wake up groggy.

If you're a pro athlete, work out in the afternoon to boost your performance.

In the afternoon, your lung function peaks, and you'll be more likely to log your best race times and speediest athletic performances.

But if working out isn't your job, it might be best to get that exercise routine out of the way in the morning instead, when there are fewer distractions to kick your schedule off course.

Studies show you're more likely to build more muscle with a daybreak workout than an evening routine. Plus, if you don't eat beforehand you can burn off more fat than you would working out after a meal.

Finally, take time for a little pause to reflect on the day before you flee the office at night.

Psychologists say we cement memories following a "peak-end rule," meaning that we tend to remember the most wonderful or intense moment of an experience, and the final one, too.

Pink suggests closing your day on a good note by taking a few moments to write down what you've accomplished and looking ahead to make a plan for tomorrow.

He has been doing this himself for about four years now, and has started to notice a trend.

"On good days, the exercise delivers feelings of completion; on bad days, it often shows me I got more done than I suspected."

Of course, not everyone's internal clock is wired the same way.

Night owls might not get their "morning" juices going until later on in the afternoon, while very early risers are ready to crash early in the evening.

Still, studies suggest that regardless of when you are most alert, we all experience a similar flow of an early high, a mid-day low, and then a final peak.

Generally, one in five people is a night owl, while roughly 60 percent to 80 percent of us do our best in the mornings.

That's according to a roundup of scientific research published in Chronobiology International.

Men are more likely to be creatures of the night than women, while older folks and young kids tend to be morning people.

Whatever time of day you work best, it's important to keep in mind that energy levels rise and fall throughout the day. Give yourself a break every now and then to recharge and refocus.

Your body will thank you, and your work will likely improve, too.

This article was originally published by Business Insider.

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