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How to Focus Better: Sleep Debt and Circadian Rhythm Are Key

The secret to better focus isn’t the latest productivity hack or energy drink. The true secret: Get the sleep you need and align your day with your body clock.
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Jeff Kahn, M.S., Rise Science Co-Founder
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Person trying to focus better by rubbing temples

Squirrel brain, shiny object syndrome, spacing out, brain fog — no matter what you call it, difficulty focusing your mind can be a real problem. You find it hard to stay on task and be productive — whether it’s at school, work, or home. This may leave you searching for answers on how to focus better.

But before you download brain training apps, try a new productivity hack, or pound ultra-caffeinated energy drinks, take a closer look at your sleep. Insufficient sleep is one of the most common but often overlooked causes of focus-related problems.

In this article, we’ll explain why keeping your sleep debt low and your daily schedule in line with your circadian rhythm are essential for focus. We’ll also tell you the steps you can take to do both.

Why Meeting Your Sleep Need Is Essential for Focus

How to focus better: woman sleeping on her desk

The brain needs sufficient sleep to function properly, and thus meeting your sleep need — the genetically determined amount of sleep your body requires — is the foundation of focus. 

Insufficient sleep has a particular impact on the brain's prefrontal cortex, the area that enables problem solving, reasoning, organizing, planning, and performing other higher cognitive functions. 

As Matthew Walker explains in his book Why We Sleep, the recycle rate of a human brain is around 16 hours. After that, the brain begins to falter. Research shows that just 17 hours of wakefulness can downgrade cognitive abilities, including reaction time. And going 17-19 hours without sleep can give you the same level of cognitive impairment as someone who has a blood alcohol level of 0.05%, the legal limit for driving in many countries.

The cumulative effects of sleep loss are also alarming. For example, if your sleep need is eight hours, after 10 consecutive nights of getting only seven hours of sleep, your brain will be just as impaired as it would if you stayed awake for a full 24 hours.

And just as an intoxicated person likely won’t be aware of the extent to which their faculties are compromised, when you become accustomed to carrying excessive sleep debt, it starts to feel normal. After just a few days of sleeping less than your genetically determined need, your brain adapts to functioning at a lower level, and that’s one of the things that makes sleep debt — the amount of sleep you missed over the past 14 days, as compared to the hours of sleep your body needed — particularly insidious. Subjectively, you think you’re doing fine, but objectively, you’re in decline across almost every measure that matters.

In addition, insufficient sleep can make you more susceptible to microsleeps. A microsleep is a short involuntary episode of unconsciousness (or partial unconsciousness) that can last a brief moment or up to several seconds, during which time the eyelids will either partially or fully close.

During a microsleep, your brain becomes blind to the outside world for a brief moment — not just to the visual realm but to all channels of perception. You may have no awareness that it has even happened, but every second or fragment of a second you microsleep is time eroding your focus. Since consciousness is indeed a prerequisite for focus, it’s easy to see how these episodes kill productivity — and can literally kill when they happen behind the wheel.

With all this in mind, it’s not surprising that people carrying high sleep debt often have a hard time staying focused and being productive.

Why Working With Your Circadian Rhythm Is Essential for Focus

Just like it’s essential to meet your sleep need for better focus, it’s also essential to work with circadian rhythm. Your circadian rhythm is the internal body clock that governs your sleep-wake cycle, as well as the predictable peaks and dips in energy you experience over each roughly 24-hour period. (You can see the exact timing of your daily energy peaks and dips in the RISE app.) Planning your day with your circadian rhythm in mind will help you keep your sleep debt low and your cognitive function high.

If you want to optimize focus and concentration, it helps to match your daily activities with your body’s natural energetic rhythm. It’s time management meets energy management. You can see the exact timing of your daily energy peaks and dips in the RISE app.

Start by planning your daily activities according to the energy levels — naturally afforded by your circadian rhythm — that you have at different times of day. Schedule difficult or important tasks that require your full attention during your morning peak and evening peak.

And relegate less demanding and less consequential to-do list items — like responding to phone calls, text messages, or social media messages — to those times of day when you’re naturally less energetic: your morning grogginess zone and your afternoon dip. Your afternoon dip can also be a great time for your regular exercise or a nap (more on this later).

It’s also important to keep a sleep-wake schedule that coincides with your circadian rhythm. This makes it easier for you to fall asleep and stay asleep, so you can wake up having gotten the sleep your body needs — allowing you to focus and function at a high level.

Knowing your chronotype can help you fine-tune your schedule. Your chronotype is your natural tendency toward an earlier or later wake time and bedtime. Whether you’re a morning chronotype or an evening chronotype — or something in between — is determined by age and genetics. In addition, variations in your light exposure and sleep schedule (as well as a few other “zeitgebers” or external cues, like timing of food and exercise) serve as signals to the specific length of your circadian rhythm each day. Mapping your wake time and bedtime according to your chronotype will help you maintain circadian alignment.

Of course, this can be easier said than done. If you’re a night owl living in society’s early-bird world, it can be challenging to adhere to your body’s natural rhythms. It is possible to take steps to become a morning person, but it will be an active process, and consistency is essential.

How to Improve Your Focus

If you’re looking for actionable steps you can take to get your focus back, you’re in the right place. Follow these tips to boost your concentration and achieve the level of productivity you’re looking for.

Keep Sleep Debt Low

RISE app screenshot showing how much sleep debt you have
The RISE app will show you how much sleep debt you have.

As we mentioned above, when you don’t get the sleep you need, you rack up sleep debt. Sleep debt is the central focus of the RISE app because it’s the number that best predicts how you’ll feel and perform on any given day. 

To have the energy you need each day, we recommend keeping your sleep debt under five hours. Higher sleep debt will make it harder to maintain focus and cognitive function. It can even put a damper on your energetic peaks.

If you’re carrying a lot of sleep debt, your focus and performance during your morning and evening peaks will be significantly less potent than if you were well-rested.

To keep sleep debt low, you should practice good sleep hygiene every day and night.

Optimize Your Day Around Your Circadian Rhythm

Instead of fighting against the ups and downs of your circadian rhythm, you can ride the waves by scheduling your day to coincide with your energetic peaks and dips. During your peaks you’ll feel the most capable and clear-headed, so this is why you should use that time for tackling difficult or important tasks. 

Here are examples of things you might do during your morning peak:

  • Lead an important meeting
  • Make or practice presentations
  • Have a difficult conversation with a client or colleague
  • Harness your creativity for writing or design projects
  • Solve a complex problem

When it comes to your evening peak, you can tackle some of the same types of tasks that you would during your morning peak. But be sure to also save some of this peak energy to nurture your relationships and hobbies, exercise, or home to-do list items. This will help you have a healthy work-life balance.

But what should you do if you have to perform earlier than usual, such as attend an important early morning meeting? By understanding your peaks and dips, you can time your day to reach your morning peak earlier. 

Here’s how it works: As your brain transitions from sleep to being fully awake, you enter into the grogginess zone (sleep inertia). You’ll experience this grogginess for about 90 minutes. So if you have an early morning obligation, aim to go to bed a little earlier the night before and wake up 90-120 minutes before you have to be “on.”   This will ensure you’ve worked through your grogginess and are in your morning peak when it’s time to perform. 

Use Your Ultradian Rhythm to Your Advantage

Once you lower your sleep debt and start working with your circadian rhythm, the next step is to leverage your ultradian rhythms. In contrast to your circadian rhythm, which repeats in roughly 24-hour cycles, ultradian rhythms have cycles that last for approximately 90- to 120-minute periods of time. During that time, your body moves through an energetic wave — climbing up to a high-energy state and then sloping down to a physiological trough.

As your body moves through one of these energetic waves, your ability to focus will vary accordingly. At the low point, the body naturally craves a period of rest and recovery. You may feel hungry, sleepy, restless, irritable, or unfocused. Ignoring the signals your body is sending can deplete your energy reserve toward the end of the workday. But using those signals as a cue to take a 10- to 20-minute break — to walk away from your workspace, talk to a coworker, or do some deep breathing exercises, for example — can improve your workday performance and stamina

In his book The 20-Minute Break, researcher Ernest Rossi divides ultradian rhythms into a user-friendly format, splitting them into 90 minutes of activity followed by 20 minutes of rest. Similar to the Pomodoro technique that breaks up sessions of focused work with short breaks, this strategy is a productive way to structure the workday because it maps with the body’s natural energy fluctuations.

Use Well-Timed Naps and Caffeine

Cup of coffee and a woman sleeping in the background

If better focus is your priority, there’s simply no substitute for consistently getting the sleep your body needs at night and working with your energy peaks and dips. But in certain situations, when lack of sleep over long periods adds up to high sleep debt and you need a short-term solution to get you through the day, a well-timed power nap or cup of coffee may help boost concentration and energy.

Neither is a perfect solution — as they won’t restore the brain’s capacity for things like complex reasoning and decision-making — but combining the two can boost alertness. 

More effective than a nap or caffeine alone, a coffee nap involves downing a cup of coffee right before lying down for a 10- to 20-minute nap. The idea is to capitalize on the restorative advantages of a nap with an added caffeine kick that wakes you up with a little burst of energy. 

Whether you decide to doze, get a dose of caffeine, or both — just be sure to time it right. To avoid their propensity for disrupting sleep at night, don’t indulge too late in the day. It’s best to nap before or during your afternoon dip and put at least 10 hours between caffeine and your target bedtime. (The RISE app can remind you of the exact timing of your afternoon dip and your ideal caffeine cutoff time so that you don’t sabotage your ability to get enough sleep at night.) 

Wind Down at the End of the Day

Your day is filled with multitasking and constant distractions, so it’s important to allow yourself a wind-down period before bed. Choose activities that will help you disconnect from the stress and activity of your day, such as:

  • Taking a warm bath or shower
  • Reading a chapter of a novel
  • Listening to calming music, like classical music
  • Doing mindfulness meditation to help you shake off the day and return to the present moment

Your nightly wind-down serves as a way to mentally and physically decelerate before sleep, so it’s not a good time to focus. Intense thinking and concentration are counterproductive during what is supposed to be a period to help smooth your transition into sleep and make it easier for you to get the sleep you need.

The RISE app tells you the ideal time for your nightly wind-down period and lets you customize it with a selection of guided relaxation sessions.

Learn How to Focus Better With RISE

RISE app screenshot showing your energy peak and dip times
The RISE app will tell you the exact timing of your energy peaks and dips each day.

Sleep is foundational to brain function and well-being — we can't focus well without it. Prioritizing sleep, using your circadian rhythm to optimize your day, and leveraging your ultradian rhythms will put you on the path to more energy and better focus.

The RISE app automatically keeps track of your sleep debt and your circadian rhythm for you. It takes the guesswork out of lowering your sleep debt and scheduling your day according to your circadian peaks and dips — so you can enjoy improved focus and a more productive day.

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Try 7 days free

The power behind your next best day

RISE makes it easy to improve your sleep and daily energy to reach your potential

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