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Introduction
If you’ve ever hit a wall of mental fog midmorning, felt your motivation vanish after lunch, or struggled to stay present during a long meeting, you’re not alone—and you’re not broken.
Like many people with insomnia, you may believe that each day is a marathon to be endured from start to finish. In reality, your brain and body are designed to pulse through natural rhythmic cycles of activity and rest throughout the day. These rhythms are usually subtle if you sleep well, gently guiding you through your days. In the face of insomnia, these rhythms can become a dominating force dictating your mood and performance. When you ignore them, you amplify suffering and undermine your quality of life and performance. But that is not your unchangeable fate. This chapter will show you how to respond to these rhythms skillfully, with awareness and respect, so they become a source of renewal and success rather than suffering.
In the framework of this book, respite is one of the four core pillars of renewal. Short, intentional breaks are one of the most universally accessible tools for creating respite—available to you anytime, without special equipment or resources. These rhythms aren’t signs of weakness—they’re valuable biological signals. You’ll learn how to recognize and work with those signals, breaking free from the marathon mindset and using them to your advantage—especially when sleep is elusive and daily life feels like an uphill climb.
My goal is simple: to help you understand the natural ebb and flow of your body’s energy cycles, to make the most of your natural activity phases, and to use short, strategic breaks to create moments of respite, clarity, and restoration—even when you can’t control how much sleep you got the night before.
The Science: What are BRACs?
You’ve likely heard of circadian (“about a day”) or 24-hour rhythms, but have you heard of ultradian rhythms? Ultradian rhythms are biological processes that are repeated several times per day. Your daytime energy follows an ultradian rhythm.
Your body and brain don’t run on a steady stream of energy. Instead, they pulse through roughly 90–120-minute cycles of alertness and fatigue throughout the day. These are called Basic Rest-Activity Cycles (BRACs)—a term coined by sleep pioneer Nathaniel Kleitman. While BRACs are most well-known in relation to sleep cycles (like deep sleep and REM sleep), they also continue when you’re awake, subtly shaping your daily rhythm of energy and fatigue.
Here’s how it works:
- The performance phase, or ultradian peak, typically lasts 90–120 minutes. During this time, your brainwave activity is faster, and you usually experience heightened alertness, focus, and mental ability. This is your natural window for deep work, creative thinking, and efficient learning. As this phase continues, metabolic byproducts build up and neurotransmitter levels shift, creating a genuine physiological need for recovery.
- This is inevitably followed by the rest phase, or ultradian trough, lasting about 20 minutes. In this phase, your brainwaves slow, and you might feel foggy, drowsy, distracted, or “spacey.” This is not weakness or poor willpower—it’s a nonnegotiable biological process that clears waste, consolidates what you’ve just learned, and resets your system for the next cycle of performance.
The BRAC’s rhythm is the outward sign of a beautifully coordinated system in your brain and body. Multiple brain areas communicate important timing signals to shape the BRAC. These signals promote regular pulses of hormones, such as cortisol, and changes in brain chemicals like dopamine, which can adjust the length of each cycle. Together, these brain and body systems create a steady but flexible rhythm that alternates between times of peak energy and focus and times of essential recovery.
The Price of Ignoring Your BRAC
Ignoring your BRAC signals—pushing through the troughs and mismanaging the peaks—comes at a cost. In the short term, you may notice more mistakes, slower thinking, or a creeping irritability that makes even small frustrations harder to handle. Over time, constantly overriding your natural rest and performance cues can keep your stress-response system switched on for too long. A system designed to pulse gently in healthy ultradian patterns may instead become overactivated and flattened, disrupting hormonal balance and setting the stage for inflammation, metabolic strain, and reduced immune defenses. This quiet internal pressure can erode both your physical and mental health, contributing to fatigue, burnout, and even chronic illness.
Double Respite: Respecting Your BRAC
Respecting your BRAC—by aligning focused work with performance phases and taking meaningful breaks during troughs—has the opposite effect. It helps your body and brain run in harmony, boosts productivity, and stabilizes your mood. Over time, deliberately respecting your BRAC strengthens resilience, reduces the cumulative load on your stress systems, and opens the door to broader healing. As a bonus, it may even create the conditions for better sleep.
Respecting your BRAC beings two kinds of respite. First, taking a real break, no matter how small, provides a brief period of relief from the general busyness and effort of the day. Second, skillfully using the performance phases of your cycle provides relief from the exertion and struggle experienced when trying to do something you are not at your best (and the self-criticism that accompany a less than your best performance).
The BRAC of the Insomniac
If you sleep well, your BRAC tends to be flexible, defined by what are called “Episodic Ultradian Events” rather than a rigidly timed rhythm. These EUEs are fluctuations in energy lasting minutes to hours that play out in response to moment-to-moment and hour-to-hour needs through your waking hours. The strength and length of these episodic ultradian events represent your body expertly alternating between rising to the occasion and then taking advantage of opportunities to restore energy.
When you live with insomnia, your BRAC often becomes fragmented or dampened. Instead of a clear rise and fall in energy, the cycle may feel flat or unpredictable—leaving you tired during peak periods and restless during recovery phases. These disruptions can make fatigue, brain fog, and mood swings worse and can create a vicious cycle: poor sleep weakens BRAC integrity, and weakened BRACs make it harder to function and recover. Sometimes the rhythm becomes desynchronized from environmental cues like light and social activity, adding to feelings of being “out of sync” with the world.
When your BRAC becomes fragmented, dampened, or desynchronized in these ways, it no longer expertly manages your day but instead becomes rigid, desperate, and demanding. Whereas a healthy person can comfortably push through a rest phase without major consequences, when you live with insomnia and try to push through, you feel deeply uncomfortable and impaired. While a healthy person may experience periods of activity as being “in the zone” or in a state of flow, you may experience the same periods as edgy, strained, and inefficient.
What Does This Mean for You?
Whereas a healthy individual can occasionally ignore their BRAC without any issues, when you live with insomnia and ignore your BRAC, you suffer tremendously. The unseen benefit is that while a healthy individual who respects their BRAC may get a little boost in mood and performance, when you respect your BRAC you can experience profound relief and a sense of being yourself again.
The rest of this chapter will focus on:
- Teaching you how to recognize the performance and rest phases of your cycle.
- How to use strategic breaks to take advantage of rest phases.
- How to make the most of the performance phases.
How to Tune into Your BRACs
Recognizing the Signs: How to Identify and Honor Your Ultradian Troughs
Your rhythm is slightly different from anyone else’s. Your cycles may last 90 minutes or lean closer to 60 or 120. The key is building interoceptive awareness—the ability to notice the subtle cues your body gives when it’s time to rest and when it’s time to perform. The transitions between the phases of your cycle are accompanied by a mix of physiological and psychological signals that are easy to miss if you’re not paying attention.
Common signs of an approaching rest phase include:
- Cognitive: A decline in focus, difficulty concentrating, mental fog, making more simple errors, or re-reading the same sentence multiple times.
- Emotional: Increased irritability, impatience, or feeling easily overwhelmed.
- Physical: Feeling fatigued or drowsy, yawning, fidgeting, or craving sugar or caffeine as your body searches for a quick energy boost.
Common signs of an approaching performance phase include:
- Cognitive: A feeling of mental clarity, faster thinking, and strong focus; ideas and solutions come more easily.
- Emotional: Increased motivation, optimism, and a sense of being “in the zone.”
- Physical: Steady, sustained energy; relaxed but alert body posture; absence of restlessness or drowsiness.
Try This 3-Step Awareness Practice:
- Track your focus and fog/fatigue for 1–2 days. Set a timer every 30 minutes and, when it goes off, check in for 30 seconds: How clear is your mind? How engaged do you feel? Keep a brief log.
- Identify your unique signals. What specifically does your body or mind do when you’re nearing the end of a performance phase? What do they do as you come to the end of a rest phase?
- Apply what you have learned. Using what you’ve learned about the timing and experience of your cycles, begin to plan how to use them well using the tips that follow.
By systematically observing your own patterns, you move from being passively controlled by your rhythms to skillfully managing them, aligning your schedule and behavior with your body’s natural ebb and flow.
Strategic Breaks: “Wallowing” in the Troughs
Once you begin recognizing the signals of an ultradian trough, take advantage of it. Really wallow in the trough. Your body and brain are ready and willing to take a pause, so make the most of the next 10–20 minutes. Here are the characteristics of a good break and some suggestions for how to take one.
What does a great break look like?
A break can be anywhere from 2 to 20 minutes, but a truly rejuvenating break is not just about timing—it’s about quality. A few minutes spent scrolling social media or checking email may fill the time but will not provide the deep recovery your brain and body need. The most effective breaks shift you away from focused, goal-driven thinking into a more restful, integrative state.
Activities to prioritize during a rejuvenating break:
- Movement: If your work has been sedentary, stand up, stretch, walk—preferably outside—or do light physical activity to boost blood flow and clear your mind.
- Sensory change: Step away from screens, gaze out a window, listen to calming music, or change your environment to reset your nervous system.
- Mindfulness and relaxation: Practice deep breathing, short meditations, or allow yourself to daydream, activating restorative brain networks.
- Physiological needs: Drink water or have a healthy, protein-rich snack away from your workspace to stabilize your energy.
- Connection or Disconnection: Choose whether to engage with others or take quiet time alone based on your natural style. If you’re more extroverted, a brief chat or positive social interaction may recharge you. If you’re more introverted, solitude and reduced stimulation may be more restorative.
These kinds of breaks help your brain consolidate information, restore emotional balance, and prepare you for the next ultradian performance phase.
You may be asking, “What’s wrong with just zoning out on my phone?” This is where the concepts of hard versus soft fascination come into play. Hard fascination activities—like fast-paced social media scrolling or intense TV—demand an elevated level of attention and fill your mind with constant stimuli, leaving little mental space for a real break. Soft fascination activities—like watching clouds drift, listening to gentle music, or walking in nature—capture your attention just enough to hold it lightly, while still allowing your mind to wander, process, and integrate. During an ultradian trough, soft fascination supports your brain’s need for recovery, while hard fascination can keep your nervous system in a semi-alert state, reducing the benefits of the break.
Break ideas for every situation:
A break doesn’t have to mean a nap or a long walk (though those are great!). Even very brief pauses can help if they are intentional and aligned with the trough of your cycle. Here are some ideas for breaks of varying lengths that can refresh your nervous system and improve your mood, energy, and focus.
Two-Minute Break Ideas (When You Have Almost No Time)
(NOTE: These can also be used during your performance phase if you just need a quick reset)
- Stand up and stretch your arms overhead while taking three deep breaths
- Gently gaze out a window to rest your eyes
- Roll your shoulders slowly forward and backward five times each way
- Close your eyes and listen to a calming sound or song snippet
- Sip a glass of water mindfully, noticing the temperature and taste
Five-Minute Break Ideas (When You’re Pressed for Time)
- Step outside and take 10 slow deep breaths
- Just breathe. Sit or lie down and place one hand on your heart, the other on your belly and observe the simple sensations of natural breathing.
- Splash cold water on your face (See the Cool Reset chapter for more on how to use the cold to your advantage)
- Listen to a favorite calming song
- Do a light stretch while looking out the window
Ten-to-Twenty-Minute Break Ideas (Ideal for Resetting)
- Take a mindful walk (without your phone), outdoors if possible
- Do an NSDR (non-sleep deep rest) practice or guided relaxation exercise (See the NSDR chapter to learn more)
- Draw, doodle, or color for fun
- Watch birds or clouds from your window
- Have a cup of something warm and comforting, doing nothing else
These moments of pause aren’t indulgent—they are brain-friendly, body-wise, and strategic. They help “close the loop” on each BRAC and prepare your system for the next wave of activity.
Strategic Action: Surfing the Wave of Your Ultradian Performance Phases
Your performance phase is prime time for doing your most important, meaningful, or demanding work. While working well may once have happened spontaneously, now you need to be more planful and intentional to be at your best. To get the most from your performance phases:
- Front-load your priorities: Tackle high-value, high-focus tasks first.
- Eliminate distractions: Silence notifications, clear your workspace, and set boundaries.
- Match the task to your energy: Use performance phases for deep work, problem-solving, or creative output.
- Use micro-breaks without disengaging: Stand, stretch, or change posture to keep energy flowing without breaking concentration.
- Build in “wind-down” minutes: As you sense the trough approaching, wrap up tasks so you can transition smoothly into recovery.
Working with your BRAC in this way can boost productivity, make work feel less like a grind, and even help you enjoy your most focused moments.
Additional Tips for Maximizing Peaks
- Set a clear intention before the peak begins: Know exactly what you want to accomplish so you can dive in without hesitation.
- Use environmental cues: Adjust lighting, temperature, and background sound to match the type of work you’re doing.
- Batch similar tasks: Group tasks that use the same type of thinking to maintain flow.
- Reflect after each peak: Take a minute to note what worked well and what didn’t so you can fine-tune future cycles.
Encouragement and Anticipatory Guidance
If you live with insomnia, you may have learned to equate rest with sleep—and to view any pause that doesn’t produce sleep as wasted. But daytime breaks that align with your BRAC are powerful tools for restoring your capacity for effort, stabilizing your mood, sharpening focus, and, over time, creating conditions that support better sleep. These pauses are not indulgences; they are strategic investments in your health and quality of life.
At first, it’s normal to miss or misinterpret your BRAC signals. You may have been conditioned to override them. Start small—one intentional pause a day is a success. With practice, your ability to notice and respond to both performance and rest phases will strengthen, helping you make the most of your natural cycles.
Key Takeaways
Learning and skillfully following your personal rhythm is a powerful act of self-care that provides respite and renewal.
Your brain and body cycle through waves of focus and fatigue every 90–120 minutes—called BRACs with distinct performance and rest phases.
Signs that you’re nearing the end of a performance phase include brain fog, restlessness, and emotional reactivity.
Signs that you’re nearing the end of a rest phase include a sense of readiness to act and the emergence of goal oriented thinking.
Taking short breaks aligned with your rest phases supports clarity, mood, and resilience—especially important when you live with insomnia.
Intentionally planning how you will use your performance phases supports productivity and reduces frustration and burnout.
