You Don’t Have to Stay in a Low Energy Trough All Day

While energy fluctuations throughout the day are normal, if you’re in a low-energy mode all day, you should examine your sleep debt and circadian alignment.
Reviewed by
Jeff Kahn, M.S., Rise Science Co-Founder
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Woman wondering why she has low energy

You've bought clear quartz and amethyst to unlock your chakras because you've heard they can help amplify your energy levels. You've downed coffee and energy drinks to perk yourself up when you feel the yawns coming. Try as you may, you still feel you're dragging your feet through life, literally.

Here’s the thing: You don't have to suffer from low energy all the time. But that's not to say, you will always ride the wave of high energy. What you have to realize is that it's completely natural to be a go-getter at certain times of day and slide into hibernation during other periods.

As you will learn, energy fluctuations are part and parcel of daily life. However, high sleep debt and an out-of-whack body clock can mute your zest during your high-spirits moments and lower your lows even more.

Ahead, we'll show you how to get enough sleep and play by the rules of your circadian rhythm so you can fill your energy tank to its brim.

Please note: The information provided is not intended as medical advice.

The Two Laws of Sleep Govern Your Daytime Energy Levels

Your body is biologically primed to give you the energy you need to do the things you desire — if you know how to harness it.

At Rise, we look at your energy levels through the lens of the Two Laws of Sleep. They are conceptualized from the two-process model of sleep regulation devised by the sleep scientist Alexander Borbély in the 1980s:

  • Sleep debt: This is the amount of sleep you've missed out on in the past 14 days relative to your sleep need and is the best indicator of how much energy potential you’ll have each day. For reference, your sleep need is the genetically determined amount of sleep your body needs to feel and function at its best. You can view your running sleep debt on the Sleep screen of the RISE app.
  • Circadian rhythm: This is more commonly known as your internal body clock. It dictates when every cell in your body is at work and at rest over the rough span of 24 hours. Your circadian rhythm is the reason why your energy fluctuates throughout the day (more on that later). In the RISE app, you can view a daily graph on the Energy screen of the exact times of your energy peaks and dips.

Knowing how to take advantage of the two levers of sleep debt and circadian rhythm will help optimize your energy levels during the day.

The No. 1 Culprit Behind Low Energy

RISE app screenshot showing how much sleep debt you have
The RISE app shows your running sleep debt, which in turn predicts your energy potential for the day.

Many of us think we can get more done on less sleep. Unfortunately, that's not how the human body works. Not meeting your sleep need means you’re accumulating sleep debt that, in turn, translates to an ever-present lack of energy, irrespective of your need to be in top form.

But how does sleep loss run a deficit on your energy reserves? It’s all about sleep homeostasis, a daytime buildup and nighttime depletion of adenosine (an organic compound that dilutes arousal and increases drowsiness).

From the moment you wake up till the minute you drift off to sleep, adenosine accumulates in your brain. Scientists also call it sleep pressure, as it helps you fall asleep when your bedtime approaches.

When you meet your sleep need, your brain has enough time to purge itself of adenosine, effectively resetting the pressure balance to zero. But when you don't get enough sleep, your brain can't clear out all traces of the organic compound before morning arrives. Consequently, you wake up feeling groggier than usual.

The resulting sleep debt flattens your natural circadian energy peaks and deepens your dips such that you're now lagging in all aspects of life that matter. From work productivity and school performance to social relationships and overall well-being, your quality of life just took a nosedive.

The No. 2 Culprit Behind Low Energy

Even though a lack of sleep is the most common cause behind low energy levels, it's not the only factor behind the scenes. The other culprit is circadian misalignment — when you're going against the rhythm of your biological clock. Think travel jetlag, social jetlag, and shift work disorder, to name a few. 

Unbeknownst to many, your circadian rhythm doesn't work the same way as the battery life on your phone. You don't start your day with a full energy tank, only for it to steadily decline as the hours tick by. And, unlike what ads for mattresses and sleep aids portray, we don't spring from our beds in the morning, with boundless energy to start the day.

Instead, it's natural for your energy levels to wax and wane as the day goes on. There are times when you're biologically poised to bring your A-game and others when you need to take a break. Think of the former as high-energy periods and the latter as low-energy stretches.

At Rise, we refer to these fluctuations as your energy peaks and dips. The timing of these peaks and dips is pegged to your unique chronobiology and, therefore, different for everyone. What’s more, the timing of your energy peaks and dips isn’t fixed. They vary from day to day, depending on factors such as your sleep patterns and light exposure.

Here's a general overview of how your energy peaks and dips occur throughout the day:

  • Wake up: It's normal to feel groggy for up to 90 minutes after your alarm goes off. Scientists call this sleep inertia.
  • Morning peak: This is the first energy peak of the day, in which you're primed to do your best work.
  • Afternoon dip: This period of low energy happens to everyone and isn't a product of your lunch (although highly processed foods and refined carbs can intensify your dip).
  • Evening peak: This is the second energy peak of the day to help you finish strong.
  • Wind-down: It's natural to feel like you're running on low fuel as you get closer to your bedtime.
  • Melatonin Window: The start of this period is marked by your dim light melatonin onset (DLMO), and it’s when your body’s melatonin production peaks. (Melatonin is a sleep-promoting hormone). It’s the optimal window of time for you to hit the sheets and give your brain enough time to relieve the sleep pressure over the course of the night.

When you don’t follow the predictable flow of your body clock, say, you go to bed later than your body is inclined to, you risk circadian misalignment. Perhaps you think you can mitigate the damage by sleeping in the next day to pay down your sleep debt. Unfortunately, that will throw your circadian rhythm even further off-course as it’s dancing to a different tune. Safe to say, your energy levels have taken a serious hit before your day even began.

Your Body Is Naturally an Energy Vessel

RISE app screenshot showing your energy peak and dip times
The RISE app shows your energy peaks and dips on the Energy screen.

Knowing the culprits behind low energy is akin to having a "Eureka!" moment. You now understand your body naturally provides the energy you need, if you know how to harness it. Learn the tools to maximize your energy levels for better daytime functioning.

Pay Down Your Sleep Debt

The quickest way to neutralize tiredness and boost energy levels is to keep sleep debt low, preferably below five hours.

RISE keeps you up to date on your sleep debt, so you'll always know if you're in the danger zone or not. If you have more than five hours of sleep debt, use these three methods to pay it down:

  • Go to bed earlier: For the next night or more, keep an earlier bedtime that's still within your Melatonin Window and meets your sleep need.
  • Nap during your dip: A nap is a productive way to bring down sleep debt during one of your low-energy periods. Our in-depth napping guide provides all the tips you need to snooze to your advantage.
  • Sleep in the next day: Consider sleeping in as the last resort. Because it can mess up your circadian rhythm, limit sleeping in to no more than an hour later than your usual wake time.
  • Pay special attention to your sleep hygiene: If you can’t prioritize an earlier bedtime or later wake time, pay extra attention to behaviors throughout the day that can positively influence sleep onset latency (how long you take to fall asleep) and fragmentation (how often you wake up during the night) for more efficient sleep.  

Remember, high sleep debt dampens your energy levels, but lowering it helps power you up for the day.

Listen to Your Circadian Rhythm

A screenshot of the RISE app calendar integration
Our newest feature, the Rise Calendar Integration, helps you match your daily activities to your energy levels so that you can feel and function at your best every single day.

Minimal sleep debt is only one vital piece of the puzzle when you want to unlock your full potential. The other key rests on how you structure your day according to your energy peaks and dips:

  • During your energy peaks, you should: Do your most challenging work. This could be anything from digesting complex topics to delivering a high-stakes presentation. You may even wish to engage in vigorous physical activity, like high-intensity interval training (HIIT) or marathon training. Remember, your body is now primed to be at its best — mentally, emotionally, and physically.
  • During your energy dips, you should: Stack dip-friendly activities. Perhaps you have tons of administrative work or household chores to clear off your to-do during your afternoon dip. Or maybe you like to unplug from your digital devices during your evening wind-down. Whichever specific activity you choose, bear in mind that your body is now inclined to rest, so go easy on it.

These lifestyle changes can be the difference between giving life your best self or the subpar version. 

We're excited to announce an even easier way to work with your daily energy peaks and dips to feel and function at your best with our newest feature — the Rise Calendar Integration. You can now see your daily energy alongside your daily schedule in your Apple or Google calendar so that you can align your energy and activities. Visit your profile — in the latest version of the RISE app — to connect your calendar.

This way, you’ll know when to aim high or set the bar low.

Take Advantage of Your Ultradian Rhythms

Hourglass on a desk

On a smaller scale, you may wish to factor in your ultradian rhythms to make the most of your energy crests and troughs.

Ultradian rhythms — or basic rest-activity cycles (BRACs) — are miniature versions of your circadian rhythm. Where the latter takes place over a roughly 24-hour time span, the former typically lasts for about 90 minutes with every wave. During this 1.5 hour stretch, your energy gradually rises to a zenith before dwindling.

This is another reason it's not realistic to expect your body to be in a high-energy mode all the time. During the rise of your ultradian rhythm, you may find it easier to focus on work, handle stressful moments, and be more efficient. When it tapers off, your body shifts into a low-energy mode. Consequently, you may feel restless and want to go for a walk. Or succumb to the looming sleepiness and sneak in some shut-eye.

To take advantage of your body's ultradian rhythm, Ernest Rossi, a researcher who authored The 20-Minute Break, suggests 90 minutes of activity followed by 20 minutes of rest. We recommend timing these 90-minute high focus sessions to each of your daily energy peaks. This helps you get the most out of your day without overextending yourself to the point where you crash and burn.

Eat Right for Energy Optimization

An artist creating a watercolor painting would not pick crayons and charcoal over brushes and paint. The same goes for what you put in your body when eating for optimal energy levels.

You may think that "energy-boosters" like coffee and energy drinks may help lift you out of your low-energy stupor. Unfortunately, their effectiveness is merely temporary and often comes with unwanted side effects.

Sure, caffeine is temporarily effective against the drowsy influence of adenosine. But it can also stay in your system for up to 10 hours. Taking it too close to your bedtime invariably lengthens the amount of time you take to fall asleep (increased sleep latency). Lo and behold, you're now less likely to meet your sleep need.

Meanwhile, a poor diet of sugary, processed foods spikes your blood sugar levels post-meal only to send them crashing down, inciting fatigue. Plus, unhealthy eating spells trouble for your waistline in the form of weight gain.

Instead of relying on your afternoon cup of coffee or sugar-laden energy drinks to pull you through your lulls, eat the right foods to sustainably boost your vitality. Fill your plate with complete meals of complex carbohydrates, whole grains, fresh fruits and veggies, lean meats, and dairy products. Not only will you be energized to check off all the tasks on your to-do list, but their satiety effect also means you feel fuller for longer to boost the odds of weight loss.

Health Issues Can Do a Number on Your Energy Levels

Various medicines on a table

Perhaps you've worked hard to keep your sleep debt low, your body clock aligned, and your diet healthy. Despite all these lifestyle changes, tiredness is still a constant companion. If that's the case, there may be a medical condition behind your low energy levels.

At the top of the list, sleep disorders are some of the most common causes of fatigue. Sleep problems manifest in various forms, from obstructive sleep apnea to restless legs syndrome to insomnia.

Lethargy is also a common symptom in non-sleep-related health conditions — like chronic fatigue syndrome, iron deficiency anemia (the body has too few red blood cells), thyroid disorders like hypothyroidism (the thyroid gland produces too few hormones), and heart disease. Specific drugs like medications for high blood pressure, sleeping aids, and antihistamines for allergies also contribute to the cloud of excessive daytime sleepiness.

So, if you've ruled out lifestyle factors for your unexplainable languor, it may be time to consult a healthcare professional to pinpoint potential medical causes.

Fill Your Energy Tank to Feel and Function at Your Best

It’s human nature to want to excel at the things you do. But you can’t do that on low fuel. Instead of looking to external energy sources (like caffeine), work with what your body is naturally equipped with.

Leveraging your ultradian rhythms and eating a healthy diet can help pave the way for sustainable energy management. But to really capitalize on your body’s built-in energy tank, keep sleep debt to a minimum and work with your circadian rhythm — the very two things the RISE app is designed for.

Here’s to feeling and functioning at your best, today and every day!

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About Rise
Rise is the only app that unlocks the real-world benefits of better sleep.

Instead of just promising a better night, we use 100 years of sleep science to help you pay down sleep debt and take advantage of your circadian rhythm to be your best.

Over the past decade, we've helped professional athletes, startups, and Fortune 500s improve their sleep to measurably win more in the real-world scenarios that matter most.

Rise Science is backed by True Ventures, Freestyle Capital, and High Alpha; investors behind category winners Fitbit, Peloton, and Salesforce Marketing Cloud.
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