For more detail, see this deep-dive on vo2 max improvement protocol.
Andrew Huberman recommends designing focus in 90-minute cycles. This is based on ultradian rhythms — biological cycles that govern the brain’s capacity for deep work [1]. For more detail, see our analysis of i built 7 passive income streams.
What Are Ultradian Rhythms?
Most people know about circadian rhythms — the 24-hour cycle that governs sleep and wakefulness. Less well known are ultradian rhythms: shorter biological cycles that repeat multiple times within a day. For more detail, see our analysis of nootropics that actually work.
Related: ADHD productivity system
See also: circadian rhythm
The human brain cycles through high-focus and low-focus states approximately every 90 minutes, a pattern first documented by sleep researcher Nathaniel Kleitman in 1963 [2]. Kleitman discovered this rhythm during his sleep research (it governs REM and non-REM sleep cycles) and later observed that the same ~90-minute oscillation continues during waking hours, sometimes called the Basic Rest-Activity Cycle (BRAC).
NIH-supported chronobiology research has confirmed that cognitive performance, alertness, and hormonal activity all fluctuate in alignment with this ultradian pattern. The practical implication: your brain is not a machine that delivers consistent output. It has natural peaks and troughs. Working with those cycles rather than against them is one of the highest-use productivity interventions available.
Dopamine, Norepinephrine, and the Focus Window
The neurochemical basis of the focus cycle centers on dopamine and norepinephrine — two catecholamines essential for prefrontal cortex function. At the start of a focus cycle, dopamine levels are primed to rise in response to effortful engagement with a task. This is why the first 5–10 minutes of focused work feel effortful: the system is not yet activated.
As you push through that initial resistance, norepinephrine release increases, sharpening attention and narrowing the focus of cognition. Around the 25–30 minute mark, most people enter what Huberman describes as the deep focus state — full cognitive engagement where complex problem-solving, learning, and creative work are most accessible [1]. The cycle peaks and then naturally declines. After 60–90 minutes of sustained effort, the neurochemical resources available for sustained focus begin to deplete.
The 90-Minute Focus Protocol
When exploring 90-Minute, it helps to consider both the theoretical background and the practical implications. Research shows that a structured approach to 90-Minute leads to more consistent outcomes. Breaking the topic into smaller, manageable components allows you to build understanding progressively and apply insights effectively in real-world situations.
- Before starting: 10 minutes of morning sunlight + delay caffeine by 90 minutes
- First 5–10 minutes: difficulty entering focus — this is normal, don’t give up
- 25–30 minutes: entering deep focus state
- 60–90 minutes: natural decline after peak
- After 90 minutes: a mandatory 10–20 minute rest [2]
Full Protocol Walkthrough
Phase 1: Visual Focus Warm-Up (2–5 minutes)
Before starting cognitive work, spend 2–5 minutes directing your visual attention at a single fixed point. Visual focus and cognitive focus share neural circuitry. Practicing visual convergence primes the attentional system for the focused work ahead [1]. Literally stare at the point on your desk or screen where you’ll begin work. The goal is to transition from the diffuse, panoramic visual mode of casual activity to the narrow, convergent mode associated with focused work.
Phase 2: Warm-Up Resistance (5–10 minutes)
The first 5–10 minutes of focused work will feel difficult. Concentration will feel slippery. Huberman emphasizes that this is neurologically normal and not a sign that focus won’t come. The dopaminergic system is ramping up. Do not stop. Do not switch tasks. Tolerate the discomfort. This phase is essentially unavoidable — the question is whether you treat it as failure or as a predictable phase of the cycle.
Phase 3: Deep Work (25–90 minutes)
Once through the warm-up resistance, sustained deep work becomes accessible. This is the window for your highest-priority cognitive tasks: writing, analysis, learning new material, complex problem-solving. Minimize interruptions. Notifications off, phone out of reach, environment optimized for single-tasking.
Phase 4: NSDR Recovery (10–20 minutes)
Non-Sleep Deep Rest (NSDR) — a term Huberman uses for practices like yoga nidra, body scans, or deliberate rest — is the mandatory recovery phase after each 90-minute cycle. It serves two functions: consolidating the information processed during the work session and restoring the neurochemical resources needed for the next cycle [1]. Ten minutes of NSDR (eyes closed, attention on body sensations or the breath) produces measurable improvements in subsequent cognitive performance. Casual browsing or conversation does not provide the same restorative effect.
Caffeine Timing Within the Cycle
Caffeine works by blocking adenosine receptors — adenosine is the molecule that accumulates during wakefulness and drives sleepiness. Drinking coffee immediately upon waking creates an artificial alert state followed by a sharper crash later in the day, because adenosine has not yet fully cleared overnight.
Huberman’s recommendation: delay caffeine intake by 90 minutes after waking. This allows adenosine to clear naturally, producing more stable alertness throughout the day. The first 90-minute work cycle can then be timed to align with the caffeine peak — approximately 30–45 minutes after consumption.
Cold Exposure Before Deep Work
Brief cold exposure (cold shower, cold face immersion, or outdoor cold exposure in cool weather) triggers a significant release of dopamine and norepinephrine — the same neurochemicals that drive focused attention. The dopamine increase from cold exposure can last 2–3 hours [1]. Ending your morning shower with 60–90 seconds of cold water is one of the most effective non-pharmaceutical ways to prime the neurochemical environment for deep work.
Adapting for ADHD
With ADHD, 90 minutes may be too long as a starting point. The ADHD brain’s executive function resources deplete faster, and the warm-up resistance phase can be more intense. Barkley (2015) notes that ADHD-related impairments in sustained attention make extended focus blocks particularly challenging without scaffolding [3].
I started with a 45-minute version and gradually extended it. The key is tolerating the discomfort of the first 5–10 minutes after starting. The brain needs time to become aroused and engaged. Additional ADHD modifications: use a visible timer so the block has a defined endpoint (reducing anxiety about an open-ended commitment), pair the session with low-level ambient or brown noise (which can increase arousal without distraction), and schedule the most important focus block 1–3 hours after waking when catecholamine levels are naturally highest.
Stacking Multiple Cycles
For knowledge workers who want to maximize deep work output, multiple 90-minute cycles can be stacked in a day — but with constraints. Most people can sustain 2–3 high-quality cycles before focus quality degrades significantly. A two-cycle day might look like this: Cycle 1 (7:30–9:00am) → NSDR (9:00–9:20am) → Cycle 2 (9:20–10:50am) → transition to meetings and administrative work. Protect the morning cycles as non-negotiable. Email, meetings, and administrative tasks are better scheduled in the afternoon when ultradian energy is lower and the cost of distraction-prone work is reduced.
Key Takeaways and Action Steps
Use these practical steps to apply what you have learned about Huberman:
- Start small: Pick one strategy from this guide and implement it this week. Consistency matters more than perfection.
- Track your progress: Keep a simple log or journal to measure changes related to Huberman over time.
- Review and adjust: After two weeks, evaluate what is working. Drop what is not and double down on effective habits.
- Share and teach: Explaining what you have learned about Huberman to someone else deepens your own understanding.
- Stay curious: This field evolves. Revisit updated research on Huberman every few months to refine your approach.
Frequently Asked Questions
What is the most important thing to know about Huberman?
Understanding Huberman starts with the basics. The key is to focus on consistent, evidence-based practices rather than quick fixes. Small, sustainable steps lead to lasting results when it comes to Huberman.
How long does it take to see results with Protocol?
Results vary depending on individual circumstances, but most people notice meaningful changes within 4 to 8 weeks of consistent effort. Tracking your progress with Protocol helps you stay motivated and adjust your approach as needed.
What are common mistakes to avoid with Focus?
The most common mistakes include trying to change too much at once, neglecting to track progress, and giving up too early. A focused, patient approach to Focus yields far better outcomes than an all-or-nothing mindset.
Last updated: 2026-04-27
Disclaimer: This article is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with any questions about a medical condition.
In my experience, the biggest mistake people make is
Your Next Steps
- Today: Pick one idea from this article and try it before bed tonight.
- This week: Track your results for 5 days — even a simple notes app works.
- Next 30 days: Review what worked, drop what didn’t, and build your personal system.
Sound familiar?
References
- Huberman, A. (2025). Essentials: Time Perception, Memory & Focus. Huberman Lab Podcast. Link
- Kleitman, N. (1963). Sleep and Wakefulness. University of Chicago Press. Link
- Ericsson, K. A., et al. (1993). The Role of Deliberate Practice in the Acquisition of Expert Performance. Psychological Review. Link
- Huberman, A. (2025). The 90-Minute Rule That Will Transform Your Focus & Productivity. Huberman Lab YouTube. Link
- Huberman, A. (2025). The 90-Minute Focus Cycle — Andrew Huberman’s Ultradian Rhythm Protocol. YouTube. Link
Related Reading
- ADHD and Rumination: How to Break the Loop of Repetitive
- The Science of Habit Formation
- ADHD Accommodations at Work [2026]
What is the key takeaway about huberman protocol for focus?
Evidence-based approaches consistently outperform conventional wisdom. Start with the data, not assumptions, and give any strategy at least 30 days before judging results.
How should beginners approach huberman protocol for focus?
Pick one actionable insight from this guide and implement it today. Small, consistent actions compound faster than ambitious plans that never start.
