Imagine yourself working on an important project, feeling the adrenaline rush as you power through your tasks like a well-oiled machine. The minutes fly by, and you make significant progress.
Then, just as you get into the groove, you suddenly hit a wall—your concentration wanes, and your productivity plummets. You become easily distracted and unmotivated. It's like someone flipped a switch, and suddenly you're stuck in an endless loop.
"Why can't I keep up this pace?" you wonder.
The good news is that you’re not alone. Most of us experience this same phenomenon at one point or another, but there is always a way to break through the wall.
One of those ways is to embrace the concept of 90-minute focus sessions.
This transformative approach is grounded in the science of ultradian rhythms and optimal work-rest cycles. Thus, strategically executing it means working harmoniously with your body's natural rhythms. You commit to working in short bursts of energy, followed by a well-deserved break.
In this article, you'll learn the science behind 90-minute focus sessions and how to maximize your productivity using them. By the end, you'll be ready to take your productivity and efficiency to the next level.
Let's dive in!
But First, What Are Ultradian Rhythms, and How Do They Work?
Our bodies naturally operate on a 24-hour cycle, going through wakefulness and sleep phases, controlled by a biological system known as the circadian rhythm. However, within this 24-hour cycle, our bodies also experience short-period rhythms or biological cycles (from minutes to 10-12 hours).
These rhythms are called ultradian rhythms.
In the spectrum, ultradian rhythms fall somewhere between the physiological and circadian rhythms. Before we move on, let’s quickly define these three rhythms that make up our biological clocks.
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Circadian Rhythms: Circadian rhythms are the 24-hour biological cycles that regulate various bodily functions and behaviors, such as the sleep-wake cycle, body temperature, and hormone production. These rhythms are synchronized with the external day-night cycle and are influenced by factors like light and darkness.
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Ultradian Rhythms: Ultradian rhythms are recurring biological patterns that occur within a 24-hour day but have shorter cycles, typically less than 24 hours. Examples include the sleep cycles with multiple stages like rapid eye movement (REM) and non-REM sleep, as well as hunger and hormonal fluctuations throughout the day.
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Physiological Rhythms: Physiological rhythms refer to regular, predictable patterns in bodily functions or processes. These rhythms can include the beating of the heart, breathing rate, and digestive processes. They help maintain essential bodily functions and often follow a daily, circadian rhythm.
So how do these ultradian rhythms work?
To illustrate how ultradian rhythms work, let's use an example of an average workday.
During the day, most of us simply try to stay awake and alert to get things done. If we are doing things effectively, we focus on the most challenging tasks first, avoiding the early morning email trap. Once we finish one job, we move on to the next.
While you may think this is the most effective way to get things done, it isn't! Unfortunately, working this way puts you in competition with your body's natural rhythm.
With some strategic rest within the day, you can actually maximize your productivity.
What exactly will you be achieving? You will be tapping into your body's ultradian rhythms. This isn't a particular hack or trick for improving your focus. Still, it's a way of working with your body and taking advantage of your body's natural rhythms to power your productivity.
If you understand how to perfectly tap into your body’s ultradian rhythms, you’ll have more done in less time by working maximally when your body is at its best and taking breaks to recharge when needed.
The Ultradian Rhythms Performance Phenomenon
The ultradian rhythms garnered attention in the 1950s through a sleep study by sleep researcher Nathaniel Kleitman. Kleitman, often called the "father of sleep," figured out the presence of ultradian cycles during sleep, unveiling the phenomenon of rapid eye movement (REM) and proposing the involvement of active brain processes during sleep.
However, Kleitman also discovered the presence of "basic rest-activity cycles (BRAC)" while individuals are awake. These daily ultradian cycles typically consist of alternating periods of high-frequency brain activity lasting 90 minutes. This is then followed by lower-frequency brain activity lasting approximately 20 minutes.
According to Jim Loehr and Tony Schwartz's book, The Power of Full Engagement:
“These ultradian rhythms help to account for the ebb and flow of our energy throughout the day. Physiological measures such as heart rate, hormonal levels, muscle tension, and brain-wave activity all increase during the first part of the cycle—and so does alertness. After an hour or so, these measures start to decline. Somewhere between 90 and 120 minutes, the body begins to crave a period of rest and recovery."
Researchers believe the delicate balance of potassium and sodium regulates these cycles. They further suggest that the brain's neurons rely on sodium and potassium ions to stimulate electrical signals. Moreover, your level of these ions plays a role in the osmosis process responsible for moving other chemicals into and out of your brain cells.
Interestingly, this may seem like a piece of science trivia, but the human brain is a resource hog. It uses the highest amount of energy than all other organs in the body, draining up to 20% of the available fuel. The majority of this energy, about two-thirds, is expended in stimulating nerve cells, while the remaining portion is allocated to cell maintenance.
For instance, when your brain is in high brain wave states, it disrupts the sodium/potassium balance. In response, the brain detects this disruption and downshifts to lower-frequency waves for a much-needed break.
This downshift is often perceived as a general fogginess, fatigue, or difficulty concentrating, but there is more to it if you can look past the fog. During that burst of energy, your body functions at its highest capacity to get far more done.
However, when you are at the low point of the cycle, it can be difficult to achieve much because you are trying to work against the body's natural rhythms, which is usually a losing battle. This phenomenon is because your body naturally goes through cycles where you feel highly energetic and alert every 90-120 minutes, followed by a period of tiredness.
But don’t despair!
Once the brain has had sufficient time to restore its sodium-potassium ratio to normalcy during the Theta state, the haze quickly dissipates, and you are now ready to recharge and enter the next cycle.
If you are fascinated by how our amazing brain works, we recommend checking out our Brain Basics: A Beginner's Guide to Neuroscience series. It’s located in our free member’s area!
What Happens If You Try to Ignore Your Natural Cycles?
You may wonder, what if I push through and try to ignore my natural cycles? Well, that's not the best idea!
When you try to power through the rest phase of your ultradian rhythm instead of allowing yourself time to recharge, you inadvertently activate your body's fight-or-flight response system.
Of course, that's bad news because the fight-or-flight response is intended for survival purposes. Therefore, when triggered, the response causes certain parts of your brain that handle logic to become less active. This occurs because you'll get creamed if you try to think logically through a threat during a fight-or-flight response.
As a result, you lose your ability to focus, which makes you hyper-alert and anxious instead.
As Loehr and Schwartz say,
"We are capable of overriding these natural cycles, but only by summoning the fight-or-flight response and flooding our bodies with stress hormones that are designed to help us handle emergencies. The long-term cost is that toxins build up inside us. We can only push so hard for so long without breaking down and burning out."
The more you try to fight against your body's natural cycles, the less productive you'll be, and the more likely you will become severely burned out. By leveraging your body’s natural rhythms, however, you can maximize your productivity more than you ever imagined.
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Tuning in Using The 90-Minute Focus Sessions
So far, we've established that the human body runs on ultradian rhythms with periods of high-frequency brain activity lasting around 90-120 minutes, followed by periods of lower-frequency brain activity lasting about 20 minutes.
This cycle means that your brain can focus for around 90 minutes and then needs to take a 20-minute break to recharge. We've also established the implications of trying to power through the rest phase of your ultradian rhythm instead of recharging.
But how do you get the best from these natural rhythms to maximize productivity?
The answer is simple: tuning into 90-minute focus sessions!
It might be challenging to tune in to your natural cycles in a culture that encourages ignoring the physical signals associated with your ultradian rhythm. In fact, 90 percent of workers don't take any defined breaks throughout the day, succumbing to the pressure of prioritizing money over time.
But ideally, you should take a break when you start to feel the fog set in and your focus draining due to ultradian rhythm fatigue. Specific productivity and cognitive benefits depend on the length of your break, but 10 to 20 minutes aligns with the length of the lull in your ultradian rhythm and helps maintain alertness. According to Ernest L. Rossi, a leading expert in this area and author of The 20-Minute Break, our mind and body need this natural period of healing and rejuvenation every 90 to 120 minutes.
The key is to learn when your body's energy levels are at their peak and take advantage of that time for maximum productivity. During this 90-minute window, you focus on one task at a time and avoid distractions. Each window should have a specific goal, and the end of the window signals a break where you take the time to recharge and prepare for the next 90-minute period.
Why Should You Use 90-Minute Focus Sessions?
Tuning into 90-minute focus sessions can help you stay on top of your work and ensure your productivity rate remains high. Breaking your work into 90-minute chunks lets you match your top energy with your to-do list, giving your productivity a big boost.
It's like teaming up with your body instead of fighting it.
By focusing on one task without getting distracted, you can make great strides in your project and reach your goals faster and more effectively. You'll also have adequate time to rest and recharge for the next session so you can perform at your best.
Anders Ericsson's 1993 study on young violinists concluded that the top performers shared the same pattern of intense bursts:
- They all practiced in the morning;
- They practiced for three sessions;
- Each session was 60-90 minutes or less; and
- There was a break between each session.
Incorporating recovery periods after intense bursts of work is critical for maximum effectiveness and productivity. This recovery period is essential for cognitive health.
Other benefits of having periods of deep focus followed by short periods of total rest include:
- Increased mental stimulation as you concentrate on one task at a time and get into the zone.
- Increased energy and mental health as you take regular breaks throughout the day.
- Improved focus as you set smaller, achievable goals for each 90-minute window.
- Increased satisfaction as you can easily track your progress and celebrate small wins.
- Enhanced creativity as you leave time for creative thinking and problem-solving.
- Reduced stress levels as you remove the pressure of needing to multitask.
7 Steps to Maximize the Power of 90-Minute Focus Sessions
It is relatively easy to incorporate 90-Minute Focus Sessions into your daily routine if you are willing and able. Here are seven simple steps to get you started.
1. Pick a theme.
Rather than randomly picking several different tasks to focus on, pick one theme for your 90-minute focus period and stick to it. This enables your brain to get in the zone and focus solely on that task.
2. Set clear, achievable goals.
Make sure to set specific and achievable goals for each focus session. This clarity gives you something to strive towards during your work window and a tangible way to measure your progress. If you don't reach it, that's fine. Just make sure to adjust your goal accordingly.
3. Chunk your goals into achievable steps
Once you have your goal, break it down into smaller, achievable steps. This will help you stay focused and make progress without getting overwhelmed. Creating smaller pieces also helps you manage your tasks on a priority list, ensuring you make the most efficient use of your time.
4. Establish a routine
Starting and maintaining a positive daily routine is key to making the most out of your focus sessions. It gives you a structure and helps you build fast-moving habits that make the routine of trying to get into productivity mode cease to be a struggle. Instead, it becomes part of you.
You can implement these routines for the best results:
- Set aside a 60 to 90-minute window to work on your most important work specifically. Monitor your body to determine your cues. When you start to feel your concentration and energy slipping, it’s a sign that you’ve reached a low point within the ultradian rhythm.
- Divide those 60-90 minutes into smaller chunks of 30-minute Pomodoro sessions, which include 25 minutes of focus and 5 minutes of rest.
- Take a break after 60-90 minutes. Leave your desk entirely during these breaks, which can take 20-30 minutes. Take a brisk walk, meditate, have a short nap, or talk with a friend. This is also a good time to add some small fitness habits into your routine. The goal is to let your brain turn off.
- Repeat the cycle as often as necessary throughout the day to get the most out of your ultradian rhythm.
Remember, the key to tuning into your 90 focus time is when you are working, make sure to stay highly focused. Do your best to avoid multitasking because research shows that it actually decreases productivity and focus!
And when you take a break, rest; hence, your brain and body will recover sufficiently during the downtime.
5. Minimize distractions
It should go without saying, but minimizing distractions during this time is essential. This could mean anything from muting your notifications, closing out of your browser tabs, blocking social media sites, or simply telling your co-workers you won't be available for a while. The goal is to be intentional about your time and give each of your prime time focus your full attention.
6. Balance your energy levels
There's no time to waste with just 90 minutes to squeeze in as much work as possible. You have to do more than manage your time. Your energy level is directly proportional to your productivity, so you must maximize the energy you can bring to each task. Therefore, allow that pressure to motivate you to think quickly and work quickly—but not so quickly that you get sloppy.
7. Track your progress and celebrate small wins
Time management is all about the big picture, so tracking your progress is a great way to stay motivated and focused. Whether you’re using an app, a spreadsheet, or simply writing down your goals on paper, being able to review your successes and failures makes it easier to adjust accordingly. It also helps to celebrate your successes, no matter how small.
Try the 90-Minute Focus Sessions
The key to successful 90-Minute Focus Sessions lies in intentional planning and understanding the power of your body’s ultradian rhythm. This means identifying when your body is at its peak focus level and productive energy so that you can plan your sessions accordingly and avoid burnout.
Once you have identified those peak times, leverage them for focused work. If you lose focus and struggle to stay productive, try leveraging your 90 minutes rhythm. Focus then rest, focus then rest.
We also recommend using brain exercises to help keep your mind extra sharp!
