#107 Why You Can't Sleep (and How to Fix It) | Dr. Michael Grandner

Oct 2, 2025 Episode Page ↗
Overview

Dr. Michael Grandner, Director of the Sleep and Health Research Program at the University of Arizona, discusses distinguishing insomnia from poor sleep, effective CBT-I strategies, detecting sleep apnea, and leveraging advanced sleep hygiene for optimal sleep and performance.

At a Glance
58 Insights
3h 44m Duration
18 Topics
7 Concepts

Deep Dive Analysis

Distinguishing Clinical Insomnia from General Sleep Problems

Understanding Conditioned Arousal and Chronic Insomnia

Cognitive Behavioral Therapy for Insomnia (CBT-I) Explained

Practical Stimulus Control Strategies for Sleep

Sleep Restriction Therapy: The 'Worst Name, Best Solution'

Prevalence and Non-Obvious Signs of Sleep Apnea

Sleep Stages: NREM 1, 2, 3 (Deep), and REM Sleep

Impact of Untreated Sleep Apnea on Sleep Architecture and Health

Non-CPAP Interventions for Sleep Apnea

Advanced Sleep Hygiene and Circadian Rhythm Optimization

Strategic Timing of Morning Light and Caffeine Intake

Melatonin: Dosing, Timing, and Misconceptions

Impact of THC, CBD, and Alcohol on Sleep

Late-Night Eating and Sleep Deprivation's Effect on Food Choices

Strategic Napping and Caffeine Use for Shift Workers

Effective Strategies for Minimizing Jet Lag

Accuracy and Pitfalls of Consumer Sleep Tracking Devices

Using Sleep as a Cognitive and Athletic Performance Enhancer

Insomnia Disorder

A persistent difficulty initiating or maintaining sleep, or waking up too early, occurring at least three nights per week for at least three months, causing daytime functioning problems, and despite adequate opportunity to sleep. A common rule of thumb for difficulty is taking at least 30 minutes to fall asleep or being awake for at least 30 minutes during the night.

Conditioned Arousal

The primary cause of chronic insomnia, where the act of trying to sleep or being in bed becomes predictably stressful. This stress creates activation (cortical, cognitive, or physiological) that makes it harder to fall asleep, strengthening the negative association and creating a self-perpetuating cycle.

Sleep-Wake Dimensions

Sleep and wakefulness are not opposite ends of a single spectrum but rather two separate dimensions. Sedatives boost the sleepiness signal, while insomnia often involves an overly high wakefulness signal, which CBT-I aims to reduce.

Stimulus Control Therapy

A core component of CBT-I, based on the idea that if a place (like your bed) is predictably tied to a limited number of activities (primarily sleep), your brain will associate that place with those activities. It involves reserving the bed strictly for sleep and sex to strengthen the 'bed equals sleep' association.

Sleep Restriction Therapy

A CBT-I component that involves initially limiting the time spent in bed to match the actual amount of sleep obtained, thereby increasing natural sleep pressure. Once sleep efficiency improves (filling the allotted time), the time in bed is gradually increased, similar to building an appetite for sleep.

Melatonin as Hormone of Darkness

Melatonin is a hormone signaling nighttime, not a direct sedative. It helps strengthen the body's natural nighttime signal, which can promote sleep in humans. Its effects are dose and timing-dependent, and it is largely ineffective for treating clinical insomnia caused by conditioned arousal.

Orthosomnia

A term for the unhealthy obsession with sleep data from wearable devices, leading to increased anxiety and stress about sleep. This fixation can paradoxically worsen sleep quality and contribute to insomnia by creating conditioned arousal around sleep metrics.

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What is the clinical definition of insomnia disorder?

Clinical insomnia is defined by persistent difficulty falling or staying asleep, or waking too early, occurring at least three nights a week for three months, causing daytime impairment, and despite adequate opportunity for sleep. Difficulty falling asleep or being awake for over 30 minutes during the night are common indicators.

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How does stress contribute to chronic insomnia?

Stress causes acute insomnia, but if the stress about not sleeping persists, it creates 'conditioned arousal.' The brain learns to associate the bed with stress and wakefulness, making it harder to fall asleep even when tired, perpetuating a cycle independent of the initial stressor.

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What are common non-obvious signs of sleep apnea?

Beyond classic snoring and daytime sleepiness, non-obvious signs include waking up in the middle of the night due to stress or for no reason, feeling like sleep is shallow, or experiencing frequent awakenings that are remembered, especially if accompanied by gasping or snorting.

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How does untreated sleep apnea affect sleep architecture and overall health?

Untreated sleep apnea can dramatically reduce slow-wave (deep) and REM sleep, increase light sleep (stage one), and make sleep generally shallower. The intermittent hypoxia and repeated arousals cause oxidative stress, leading to problems in various organ systems, including increased risks for neurodegeneration, heart issues, and metabolic problems.

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What are effective non-CPAP treatments for sleep apnea?

Non-CPAP options include mandibular advancement devices (retainers that push the jaw forward), myofacial therapy (exercising airway muscles), electrical tongue stimulation devices like ExciteOSA, and implantable pacemakers for the tongue muscle (Inspire).

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How can morning light exposure improve sleep at night?

Bright morning light helps set the circadian clock, initiating a timer that prepares the body for sleep 16-17 hours later. It also strengthens the circadian amplitude, leading to a more robust nighttime sleep signal, and inoculates against the negative effects of light exposure at night.

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What is the optimal timing for caffeine intake to maximize alertness and avoid sleep disruption?

It's recommended to wait at least an hour after waking to consume caffeine, as adenosine levels are lowest in the morning, and the peak effects of caffeine occur about 30 minutes after ingestion. This strategy leverages natural alertness and saves caffeine for when it's most needed, typically stopping four to six hours before bedtime.

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What are the effects of THC on sleep?

THC can help with sleep onset and maintenance initially, but its sleep-promoting effects often fade over time, leading to dose escalation. It can also be a potent REM sleep suppressor and may cause an insomnia and REM rebound (vivid nightmares) upon cessation.

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Why does sleep deprivation often lead to unhealthy eating habits?

Sleep-deprived individuals tend to consume 350-600 extra calories per day, primarily through increased snacking after dinner. This occurs because the brain, when awake past its desired sleep time, seeks reward and calorie-dense, palatable foods, while decision-making and reward processing are impaired.

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How accurate are consumer sleep tracking devices for measuring sleep stages and overall sleep quality scores?

Wrist-based devices are highly accurate (around 90%) for distinguishing sleep from wakefulness and heart rate data. However, sleep stage detection is a ballpark estimate (60-80% accurate), and metrics like 'sleep score' or 'readiness' are often based on proprietary, unpublished algorithms, making their interpretation and utility for actionable insights questionable.

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How can athletes use sleep to enhance performance and prevent injuries?

Athletes can enhance performance by gradually extending sleep duration (e.g., 15 minutes earlier bedtime) and 'sleep banking' good sleep in the weeks leading up to competition. Sleep deprivation, insomnia, and daytime sleepiness are significant predictors of injury risk, highlighting sleep's role in recovery and cognitive function.

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What is the most effective way to reduce nighttime urination awakenings?

The most effective way is to address underlying causes of nighttime awakenings, with untreated sleep apnea being a leading cause. Additionally, people can train themselves to not immediately go to the bathroom upon waking if it's not truly necessary, reducing the conditioned response to awakenings.

1. Prioritize CBTI for Insomnia

Recognize Cognitive Behavioral Therapy for Insomnia (CBTI) as the gold standard treatment, as it reliably targets the underlying problem of conditioned arousal and is effective even with co-existing conditions like chronic pain or sleep apnea.

2. Surrender Sleep Control

Learn to surrender control over sleep, especially when experiencing performance anxiety about not sleeping, because trying harder to sleep (effort) adds energy to the system and makes it more difficult to fall asleep.

3. Bed for Sleep & Sex Only

Implement stimulus control by strictly associating your bed with sleep (and sex), avoiding other activities like scrolling on your phone, working, or ruminating in bed, to strengthen the predictable link between bed and sleep.

4. Leave Bed During Night Awakenings

If you wake up in the middle of the night and cannot fall back asleep within a few minutes, get out of bed to break the negative association and prevent stress from escalating, returning only when you feel ready to sleep.

5. Practice Time-in-Bed Restriction

Practice ‘restriction of time in bed’ by initially limiting your time in bed to the actual amount of sleep you’re getting, then gradually increasing it as your sleep efficiency improves, to build natural sleep pressure.

6. Prioritize Morning Bright Light

Get 15-30 minutes of bright outdoor light exposure (e.g., a morning walk/run) early in the morning to set your circadian clock, strengthen your daytime rhythm, and inoculate yourself against the negative effects of light exposure at night.

7. Plan Sleep Backwards

Plan your sleep schedule by working backward from your desired wake-up time, considering how much sleep you need, the time required to wind down, and any morning activities, to ensure you budget sufficient time for sleep and preparation.

8. Screen for Sleep Apnea

Consider getting tested for sleep apnea if you frequently wake up suddenly for no reason, can’t get back to sleep, or feel like you can’t get enough quality sleep despite adequate time, as it’s surprisingly common and home tests are readily available.

9. Address Sleepiness for Injury Prevention

Prioritize addressing daytime sleepiness and insomnia, as these are stronger predictors of injury (e.g., concussions in athletes) than just sleep duration, indicating impaired focus and decision-making.

10. Practice Sleep Banking

Practice ‘sleep banking’ by consistently getting sufficient quality sleep for a week or two leading up to high-stakes events (e.g., competitions), as this builds resilience and minimizes the negative impact of one or two nights of poor sleep.

11. Insulate Sleep Environment

‘Bubble wrap’ your sleep by using simple tools like a cloth eye mask and earplugs to insulate yourself from minor environmental disturbances, which can consolidate sleep (especially deeper sleep) and lead to improved cognitive performance.

12. Sufficient Pre-Bed Wind Down

Dedicate at least 30 minutes before bed to a ‘wind down’ routine, dimming lights (preferably to orange tones) and metaphorically detaching from mentally activating tasks to allow your body and mind to slow down.

13. Mindful Phone Use Before Bed

When using your phone before bed, do so outside of bed, or if in the bedroom, stand or sit upright (not lying down) to maintain awareness of your body’s sleep signals and avoid associating the bed with wakefulness.

14. Curate Pre-Bed Media

Curate your pre-bed media consumption by choosing content that is not mentally activating and that you can easily disengage from if an ‘alarm’ went off, avoiding anything that makes you want to continue for ‘five more minutes’.

15. Strategic Melatonin Dosing

Use melatonin strategically: a 0.3-0.5 mg dose 5 hours before bedtime can shift your clock earlier, while the same dose in the morning can delay it. Be aware that over-the-counter doses (e.g., 5mg) are often higher than labeled due to manufacturing practices, so if you feel groggy, reduce your dose.

16. Limit Alcohol Before Bed

Limit alcohol consumption before bed, as while it may induce faster initial sleep, its rapid metabolism often leads to rebound activation and awakenings later in the night, disrupting overall sleep quality.

17. Avoid Late-Night Eating

Avoid late-night eating, especially calorie-dense or highly palatable foods, as it often stems from emotional reasons or being awake past your body’s natural sleep time, and can disrupt metabolic processes and sleep quality.

18. Caffeine Cut-off Time

Stop consuming caffeine at least four to six hours before your intended bedtime to avoid it interfering with your ability to settle down and fall asleep.

19. Delay Morning Caffeine

Wait at least an hour after waking before consuming caffeine, as your adenosine levels are lowest in the morning and your natural sleep inertia will dissipate, allowing you to leverage caffeine’s effects more effectively when adenosine has accumulated.

20. Avoid Long-Term THC for Sleep

Avoid using THC for long-term sleep aid, as its sleep-promoting effects fade, it can suppress REM sleep, and discontinuing use often leads to insomnia rebound and vivid, unpleasant dreams.

21. Melatonin Not for Insomnia

Avoid using melatonin to treat insomnia, as it is generally ineffective for conditioned arousal where the body already recognizes it’s nighttime but cannot sleep due to stress.

22. Ignore Wearable Sleep Scores

Largely ignore ‘sleep scores,’ ‘sleep quality,’ ‘readiness,’ or ‘recovery’ metrics from wearables, as they are often non-transparent, not scientifically vetted, and may not provide actionable or reliable information.

23. Avoid Sleep Data Obsession

Avoid ‘orthosomnia’ by not obsessing over wearable sleep data, as fixating on imperfect metrics can create performance anxiety, worsen sleep, and lead to insomnia. Remember that sleep doesn’t need to be perfect to be perfectly fine.

24. Trust Wearable Sleep/HR Data

Trust wearable device data primarily for tracking sleep versus wake times and heart rate, as these metrics are captured with high accuracy and have robust algorithms.

25. Caution with Sleep Stage Data

Interpret wearable sleep stage data with caution, understanding it’s a ballpark estimate (60-80% accurate) and not a precise measure; a low reading for deep sleep doesn’t necessarily mean you’re not getting enough, but rather that the algorithm may not be picking it up perfectly.

When using wearable data, focus on long-term trends (weekly or monthly) rather than obsessing over single-night readings, as trends provide more meaningful insights into your sleep patterns.

27. Identify Sleep Data Anomalies

Use wearable data to identify discrepancies between your perceived sleep and recorded sleep, or to spot anomalies like unusual heart rate fluctuations or misplaced sleep stages, which can signal underlying issues like sleep apnea, pain, or environmental disturbances.

28. Address High Nighttime Heart Rate

If your wearable shows a consistently high or rising heart rate during the night, investigate potential causes such as late-day caffeine/alcohol, medication timing, pain/inflammation, an uncomfortable mattress, or lack of pre-bed relaxation, and address them accordingly (e.g., breathing exercises, temperature modulation).

29. Reduce Nighttime Urination

If you frequently urinate at night, first investigate underlying causes like untreated sleep apnea. If no medical cause, try to fall back asleep without going to the bathroom, as you might be conditioned to urinate during natural awakenings.

30. Daytime Habits for Sleep Quality

Improve overall sleep quality by focusing on daytime habits: get regular physical activity and bright light exposure, eat a healthy diet (especially avoiding late-night unhealthy eating), and work to reduce systemic inflammation in your body.

31. Address Partner’s Sleep Issues

If your bed partner’s sleep issues (e.g., snoring, movement) are disrupting your sleep quality, encourage them to get tested and treated, or consider practical solutions like separate blankets or even separate mattresses pushed together to minimize disturbance.

32. Assess Sleep by Alertness

Assess if you’re getting enough sleep by observing your daytime alertness: if you can’t stay conscious in a quiet, dark room for 20 minutes, or if you fall asleep immediately when your head hits the pillow, you likely need more or better quality sleep.

33. Gradually Extend Sleep (Younger Adults)

If you are a younger adult or athlete, gradually extend your sleep duration by 15-minute increments (e.g., by going to bed earlier) to potentially improve physical performance, strength, and mental sharpness.

34. Read Paper Books Before Bed

Engage in reading physical books before bed, as it’s a self-paced activity that helps you connect with your body’s sleep signals without overstimulation, allowing you to recognize when you’re truly ready for sleep.

35. Magnesium & Glycine for Sleep

Consider magnesium and glycine supplements to help promote sleep, as both have shown evidence of aiding in falling asleep and staying asleep better.

36. Calming Supplements for Relaxation

If you primarily need calming and relaxation to prepare for sleep (and don’t have insomnia), consider supplements like L-theanine or chamomile, as they can be helpful for relaxation even if they don’t directly induce sleep.

37. Avoid Pre-Bed Glutamine

Avoid supplements containing glutamine before bed, as it can be activating and interfere with sleep, especially for those experiencing insomnia.

38. Take B12 in Morning

Take B12 supplements in the morning, not at night, because it helps boost light’s ability to suppress melatonin and can contribute to morning alertness.

39. CBD for Sleep (Low Hopes)

Approach CBD for sleep with low expectations, as research is murky, with some studies showing benefit, others no effect, and some even showing worsened sleep; its effects are likely secondary to anxiety reduction rather than direct sleep promotion.

40. Immediate Jet Lag Time Shift

For long-haul flights across many time zones, immediately adjust your mindset to the destination’s local time upon boarding the plane. Attempt to sleep during what would be nighttime at your destination, even if fragmented, and then power through the first day upon arrival with light exposure and activity.

41. No Naps for Jet Lag

Avoid napping while adjusting to a new time zone, as it can send mixed signals to your body and disrupt the adjustment process, especially if you drop into deep sleep.

42. Light & Melatonin for Jet Lag

Strategically use light and melatonin for jet lag: expose yourself to bright light during the destination’s daytime (no sunglasses in the morning) to signal wakefulness, and use melatonin at the destination’s evening to signal nighttime.

43. Exercise Upon Jet Lag Arrival

Exercise immediately upon arriving at your destination to send a strong daytime signal to your body, promoting alertness and helping to suppress any lingering melatonin from your original time zone.

44. Consistent Shift Work Schedule

For shift workers, aim for consistency in your shift schedule (e.g., permanently adapting to a night shift) to minimize the health damage caused by frequently shifting between different sleep-wake patterns.

45. Strategic Napping Techniques

Use strategic napping: for a ‘power nap,’ keep it short (15-20 minutes, or up to an hour earlier in the day) to avoid deep sleep; for a ‘sleep replacement nap,’ allow 2-3 hours to complete a full sleep cycle, beneficial for shift workers or athletes with disrupted nighttime sleep.

46. Treat Positional Sleep Apnea

If your sleep apnea is positional (worse when sleeping on your back), use a positional therapy device or a simple method like sewing a tennis ball onto the back of a t-shirt to encourage side sleeping.

47. Use Mandibular Advancement Devices

For mild to moderate sleep apnea, consider a mandibular advancement device (a dental retainer that pushes your jaw forward) to create muscle tone and keep your airway open.

48. Myofacial Therapy for Airway

Explore myofacial therapy or specific breathing exercises (like those used for didgeridoo playing) to strengthen upper airway muscles, which can help maintain muscle tone during sleep and alleviate mild apnea.

49. Mouth Taping Caution

Use mouth taping only if your issue is mild snoring or mouth-breathing without underlying sleep apnea; avoid it if you have sleep apnea and need to open your mouth to breathe, as it could worsen the condition.

50. Re-Test Sleep Apnea Treatment

If you’re using a sleep apnea treatment (like a mandibular device), get retested periodically (e.g., every couple of years) while using the treatment to confirm its continued effectiveness and ensure it’s properly adjusted.

51. Predictable Nighttime Routine (Irregular Schedule)

If your schedule is irregular (e.g., due to travel or shift work), establish a highly predictable nighttime routine, performing the same actions in the same order, and bringing familiar items (like a pillowcase) to create consistent sleep cues.

52. Find a CBTI Professional

Seek out a trained CBTI professional, either in-person or via telehealth, as specialized expertise can be crucial for effective treatment, though self-help resources can also be a starting point.

53. Overcome Bedtime Procrastination

Address ‘revenge bedtime procrastination’ by recognizing that improving sleep can lead to increased daytime efficiency and productivity, potentially freeing up more personal time during the day, rather than sacrificing sleep for late-night personal time.

54. Align with Chronotype

Align your daily schedule with your chronotype where possible; if you’re a night owl with early morning commitments, optimize your morning routine to be as short as possible to maximize late-night personal time, and maintain a consistent sleep-wake schedule seven days a week.

55. Understand Chronic Insomnia’s Root

Understand that chronic insomnia is often caused by ‘conditioned arousal,’ where the act of trying to sleep becomes predictably stressful, leading to a self-perpetuating cycle of activation and difficulty sleeping. This understanding is foundational for CBTI.

56. Self-Assess Chronic Insomnia

Self-diagnose chronic insomnia if you consistently take >30 mins to fall asleep or are awake >30 mins during the night, at least 3 nights/week for 3+ months, and it causes daytime problems, while giving yourself adequate sleep opportunity.

57. Consult Sleep Specialist for Problems

If you suspect a serious sleep problem based on wearable data or symptoms, consult a sleep specialist who can properly diagnose and treat the issue using established medical protocols, rather than relying solely on wearable metrics.

58. Sleep for Resilience & Performance

Prioritize improving your sleep to enhance overall resilience (physical, emotional) and boost cognitive and athletic performance, including reaction time, speed, and mental sharpness.

The enemy of sleep is effort.

Dr. Michael Grandner

Sleep is not something that you do. Sleep is something that happens to you when the situation allows for this.

Dr. Michael Grandner

If I say bed sleep, bed sleep, bed sleep, bed sleep, I say bed, you say? Sleep. Correct. If I say bed sleep, bed wake, bed think, bed wake, bed sleep, bed wake, bed sleep, bed think, bed surf, maybe. Scroll. You have no idea. Right. You have no idea what's coming next. You can't predict the pattern.

Dr. Michael Grandner

People are not a good judge of how impaired they are due to sleep deprivation.

Dr. Michael Grandner

You cannot caffeinate away complex decision-making. You just make bad decisions faster.

Dr. Michael Grandner

A bathroom scale is not a weight loss program.

Amy Athey (attributed by Dr. Michael Grandner)

Sleep doesn't have to be perfect to be perfectly fine.

Dr. Michael Grandner

CBT-I Stimulus Control for Insomnia

Dr. Michael Grandner
  1. Reserve your bed strictly for sleep and sex; avoid other activities like scrolling, working, or ruminating in bed.
  2. If you cannot fall asleep within a reasonable time (e.g., 20-30 minutes) or wake up in the middle of the night and cannot fall back asleep, get out of bed.
  3. Go to another room or sit up in bed (not lying down) and engage in a non-stimulating activity until you feel sleepy again.
  4. Return to bed only when you feel genuinely sleepy.
  5. Repeat this process as many times as necessary throughout the night.
  6. Avoid adding stress or effort to falling asleep; surrender control and trust that sleep will come when your body is ready.

CBT-I Sleep Restriction (Restriction of Time in Bed)

Dr. Michael Grandner
  1. Determine your current average actual sleep time (e.g., 6 hours of sleep in 8 hours in bed).
  2. Initially, restrict your time in bed to only the amount of time you are actually sleeping (e.g., 6 hours).
  3. Maintain this restricted time in bed consistently, even if it means feeling more tired initially, to build up strong sleep pressure.
  4. Once you are efficiently filling almost all of your allotted time in bed with sleep, gradually increase your time in bed (e.g., by 15-minute increments).
  5. Continue to expand your time in bed as long as you maintain high sleep efficiency, aiming for your optimal sleep duration.

Optimizing Morning Routine for Sleep and Alertness

Dr. Michael Grandner
  1. Wake up at a consistent time each day, even on weekends, if possible, to anchor your circadian rhythm.
  2. Immediately upon waking, seek bright outdoor light for 15-30 minutes (e.g., a morning walk or run) to suppress melatonin and set your internal clock.
  3. Delay your first cup of caffeine for about an hour after waking to allow natural sleep inertia to dissipate and adenosine levels to rise, maximizing caffeine's later effects.
  4. Engage in physical activity or exercise early in the day, as movement is a powerful circadian phase shifter.

Jet Lag Adjustment Strategy

Dr. Michael Grandner
  1. Before the flight, consider strategic, slight sleep deprivation to make it easier to sleep on the plane.
  2. As soon as you board the plane, mentally switch to the local time zone of your destination.
  3. If flying eastward (e.g., US to Europe), try to sleep on the plane, treating the flight duration as your nighttime, using eye masks, earplugs, and low-dose melatonin if needed.
  4. Upon arrival, immediately expose yourself to bright outdoor light and engage in physical activity to send a strong daytime signal, even if it's your biological night.
  5. Avoid napping during the adjustment period to prevent sending mixed signals to your body and to build up sleep pressure for local nighttime sleep.
  6. Use low-dose melatonin (0.5 mg) in the evening of the new time zone to help shift your internal clock earlier, if flying eastward.

Sleep Extension for Enhanced Performance (Younger Adults/Athletes)

Dr. Michael Grandner
  1. Gradually increase your time in bed by 15-minute increments, aiming to go to bed 15 minutes earlier than usual.
  2. Ensure you are genuinely tired before attempting to go to bed earlier to maintain good stimulus control.
  3. Continue to increase bedtime by 15-minute increments as long as you are able to fill the extra time with sleep and feel benefits.
  4. Track objective performance metrics (e.g., speed, strength, cognitive sharpness) to observe improvements that may not be subjectively noticeable.
  5. Prioritize 'sleep banking' by consistently getting good sleep in the weeks leading up to important competitions or cognitively demanding periods, rather than solely focusing on the night before.
30 minutes
Time to fall asleep or be awake during the night (rule of thumb for insomnia) At least 30 minutes to fall asleep or be awake during the night trying to sleep, occurring at least 3 nights per week for 3 months, indicates chronic insomnia.
One out of three people
Prevalence of sleep complaints in the U.S. Has some sort of sleep complaint or problem (falling asleep, staying asleep, not feeling refreshed).
One in 10 people
Prevalence of insomnia disorder in the U.S. Likely meets the criteria for an insomnia disorder if assessed.
One out of four or five
Prevalence of sleep-related breathing issues in men over 30 Increases to 50/50 if BMI is over 30.
4 to 5 events per hour
Normal range for breathing pauses per hour during sleep Sleep apnea begins at 5 events per hour (mild), becoming moderate at 15 events per hour.
10 times or more
Typical number of awakenings per night for adults Most adults wake up this many times but don't remember it due to short duration.
30 minutes
Time for caffeine to reach peak effects after ingestion Caffeine's peak alerting effects occur approximately 30 minutes after consumption.
4 to 6 hours
Recommended last caffeine intake before bed For most people, this is the last time they should consume caffeine. Some individuals may need 10-12 hours.
350 to 600 calories
Extra calories consumed per 24 hours when sleep deprived Consumed primarily after dinner, when people are kept up past their body's desired sleep time.
Over an hour
Increase in total sleep time for college athletes after sleep education Time in bed increased by 40 minutes, total sleep time by over an hour, leading to better grades and productivity.
About 90%
Accuracy of wrist-based movement for sleep/wake detection Predicts sleep vs. wake relative to brainwave activity with high accuracy.
60% to 80%
Accuracy of wearable devices for sleep stage detection A ballpark estimate, not perfect or gold standard, but not useless.
7 hours
Recommended minimum sleep duration (new guideline) Based on data showing no distinguishable difference in most cases between 7 and 8 hours; 6 hours or less typically shows problems.