Optimize Your Sleep: Dr. Allison Brager on Efficiency, Resilience & Performance (Perform Podcast Summary)

In this episode of "Perform with Dr. Andy Galpin," host Dr. Andy Galpin speaks with Dr. Allison Brager, a neuroscientist specializing in sleep, particularly sleep resilience. Dr. Brager shares insights from her extensive research across diverse populations, including athletes, military personnel (even in extreme environments like Antarctica and space), and the general public. The conversation delves into understanding individual sleep needs, the science behind chronotypes and sex differences in sleep, practical strategies for enhancing sleep efficiency, the role of napping, and how to build resilience to sleep disruption caused by factors like travel, shift work, or demanding schedules. The episode aims to provide listeners with evidence-based knowledge and actionable advice to optimize their sleep for better performance, health, and overall well-being.

Key Insights

• Contrary to popular belief, West Coast NFL teams have a performance advantage during the regular season because game times often align better with their natural circadian peaks compared to East Coast teams.
• Chronotype (being a morning lark or night owl) has a strong genetic component (e.g., linked to Per1/Per2 genes) and is difficult to fundamentally change, though behavior can be adapted temporarily, often at a cost to well-being or performance.
• Biological sex differences influence sleep: Males tend to build sleep pressure faster (leading to more daytime sleepiness and quicker sleep onset), while females may take longer to fall asleep but often achieve more efficient, restorative sleep. These differences appear linked to chromosomal factors (like the SRY gene) beyond just hormones.
• Napping can be beneficial, especially for those with insufficient sleep. Short naps (under 30 minutes) can improve alertness and performance without significantly disrupting nighttime sleep for most people. The "Nappuccino" (caffeine before a short nap) can reduce grogginess upon waking.
• Sleep resilience, the ability to maintain function despite sleep challenges, is crucial but has limits. While mindset helps buffer short-term (e.g., 1-2 nights) sleep loss, chronic sleep deprivation (beyond ~72 hours) significantly impairs performance regardless of perception or caffeine intake.
• Improving sleep efficiency involves more than just sleep hygiene; consistent daily routines (zeitgebers) like regular meal times, light exposure, exercise timing, and social interaction strongly signal the body's circadian clock, leading to more consolidated and effective sleep, even with constrained sleep opportunities.
• Strategic use of tools like caffeine (timed, dosed appropriately), blue light blockers, specific supplements (e.g., magnesium bicarbonate, tart cherry extract), and temperature regulation (e.g., hot shower before bed) can support sleep, while others like high-dose or chronic melatonin use for nightly sleep can be counterproductive.

Circadian Rhythms, Chronotypes, and Athletic Performance

The discussion begins by debunking the myth of an East Coast sports advantage. Dr. Brager explains research, including her own confirmation of earlier studies, showing West Coast NFL teams perform better during the regular season when playing on the East Coast. This is attributed to games aligning more favorably with their internal biological clocks (circadian rhythms). Playing closer to their mid-morning/early evening peak alertness, driven by factors like rising cortisol levels, gives them an advantage and correlates with lower injury rates compared to East Coast teams playing later relative to their internal clocks. This phenomenon has been observed across various professional sports leagues (NBA, NHL, MLB).

Dr. Brager emphasizes the strong genetic basis of chronotype – whether someone is naturally a morning person or a night owl. She links this to specific circadian clock genes (like Per1 and Per2) and suggests individuals often self-select into sports or professions that align with their chronotype (e.g., gymnasts or boxers might lean towards evening types). While acknowledging environmental influences (like family habits) play a role, she argues, based on preclinical models and personal experience (trying to adapt to early military schedules as a night owl), that one's fundamental chronotype is largely fixed. Forcing a mismatch (e.g., a night owl working a 7 am job) leads to surviving, not thriving, and potentially increased illness risk. Interestingly, research on rugby teams suggests greater chronotype diversity can be advantageous for teams playing at various times, whereas teams competing consistently at night (like NBA/NHL) might benefit from selecting more evening types.

Sex Differences in Sleep

Dr. Brager discusses her postdoctoral research using the "four core genotype" mouse model, which allows scientists to disentangle the effects of sex chromosomes (XX vs. XY) from hormonal influences (presence/absence of gonads). This research highlighted that chromosomal sex, particularly the SRY gene on the Y chromosome, plays a significant role in sleep regulation.

Key findings, supported by both animal models and older human studies (from the 1980s, now being revisited), include:

• Sleep Pressure: Males build sleep pressure (driven by adenosine accumulation in the brain) more rapidly throughout the day, making them more prone to daytime sleepiness and napping.
• Sleep Onset: Males typically fall asleep faster than females.
• Sleep Quality/Efficiency: Although females may take longer to initiate sleep (potentially linked to higher vigilance/acetylcholine activity, perhaps evolutionarily tied to childcare), they tend to enter restorative deep sleep (Stage 3) and REM sleep more quickly and have greater overall sleep efficiency throughout the night.
• Total Sleep Time: Females may average slightly more sleep (around 20-30 minutes) than males, but Dr. Brager cautions against overstating the clinical significance or creating anxiety around this difference.

The underlying mechanisms likely involve differences in adenosine metabolism and potentially neurotransmitter systems like acetylcholine, though more research is needed, especially regarding the direct impact of chromosomal vs. hormonal factors in humans.

Napping: Benefits, Stigma, and Best Practices

Despite lingering stigma, particularly in structured environments like the military (where it can be seen as laziness), napping is presented as a potentially valuable tool. Historically, prominent figures like President Eisenhower utilized naps. The benefits are most pronounced for individuals experiencing chronic sleep insufficiency.

Best practices include:

• Duration: Generally, naps should be kept short (20-30 minutes) to boost alertness and performance without interfering with nighttime sleep onset or quality. For chronically sleep-deprived individuals or shift workers, a longer nap (around 90 minutes) allowing a full sleep cycle might be beneficial.
• Timing: Napping during the natural afternoon dip in circadian alertness (often 2-4 pm) can be effective.
• The "Nappuccino": Consuming caffeine (e.g., ~200mg) just before a short (approx. 20 min) nap can help counteract sleep inertia (grogginess) upon waking, as the caffeine takes effect around the time the nap ends.

However, napping isn't for everyone; some individuals report feeling worse after napping, suggesting personal experimentation is key. Dr. Brager also touches upon historical multiphasic sleep patterns (common before artificial lighting), suggesting that segmented sleep (e.g., a long nap plus nighttime sleep) isn't inherently unhealthy and aligns with natural circadian dips.

Sleep Resilience in Extreme Environments & Shift Work

Dr. Brager shares insights from studying sleep in challenging conditions. Her research in Antarctica revealed that while sleep patterns changed seasonally (fewer, longer bouts in winter vs. more, shorter bouts in summer), the total 24-hour sleep duration, blood pressure rhythms, and cognitive performance remained remarkably stable throughout the year, highlighting the robustness of the human sleep system even with extreme light/dark cycle variations.

Sleep in space presents unique challenges, with anecdotal reports varying among astronauts. Dr. Brager hypothesizes that disruptions to the vestibular (balance) system in microgravity, which connects to the thalamus (a key sleep regulation center), might underlie some sleep architecture changes observed. NASA employs sophisticated light management protocols to help astronauts maintain circadian alignment.

The concept of "sleep resilience" is emphasized – the ability to function effectively despite suboptimal sleep. While psychological factors (believing one is resilient) can buffer performance decline after one or two nights of poor sleep, this effect breaks down after about 72 hours of cumulative sleep debt. Chronic sleep deprivation inevitably impairs cognitive and physical function. This is starkly illustrated by the health consequences of shift work (working overnight), which fights against natural biology and is linked to significantly reduced lifespan (potentially up to 15 years) and increased risk of various diseases, leading the WHO to classify it as a probable carcinogen. Dr. Brager suggests genetic screening for chronotype could potentially help select individuals better suited for night shift roles.

Practical Strategies for Improving Sleep Efficiency

Beyond basic sleep hygiene (dark, cool, quiet room), Dr. Brager stresses the power of consistent daily routines – known as "zeitgebers" (time cues) – for enhancing sleep efficiency, even when total sleep time is limited. These include:

• Consistent Timing: Regular times for waking, meals, exercise, work, and social interaction anchor the circadian rhythm.
• Light Exposure: Morning sunlight exposure and minimizing bright light (especially blue light, potentially using blockers) in the hours before bed are critical.
• Caffeine Strategy: Use caffeine strategically for alertness (up to 200mg per dose, repeated every 4-6 hours if needed), but cease intake 6-8 hours before bedtime.
• Exercise Timing: Aligning workouts with one's chronotype (e.g., morning for morning types capitalizing on cortisol) may be optimal.
• Pre-Bed Routine: While long routines aren't essential if daily schedules are consistent, simple actions like a hot shower (which triggers compensatory body cooling) can aid sleep onset.
• Nutrition/Supplements: Certain foods/supplements may help: tart cherry extract (recovery/sleep), potentially kiwi fruit or warm milk (some evidence for sleep-promoting factors), and magnesium bicarbonate (for relaxation/sleep maintenance). Avoid routine high-dose melatonin for nightly sleep; it's better suited for phase-shifting during travel (low dose, 1-3mg, short-term).
• Breathing: Nasal breathing promotes relaxation (parasympathetic activity). Nasal dilators can help, while mouth taping at night carries risks if the diaphragm isn't well-trained for nasal breathing during sleep; practice diaphragmatic nasal breathing during the day instead. Avoid cold plunges right before bed, as they trigger a warming response counterproductive to sleep onset.

She illustrates these principles with a detailed hypothetical scenario for a high-performing executive with a demanding schedule (midnight-6 am sleep window), emphasizing consistency, timed caffeine, light management, and targeted supplements over complex rituals.

Regarding sleep banking or extension (making up for lost sleep), she advises gradual changes (adding/subtracting sleep in 30-minute increments per week) to avoid disrupting the circadian system excessively. Sleeping in on weekends can partially mitigate weekday sleep debt and is associated with reduced cardiovascular risk, provided the bedtime remains relatively consistent.

Conclusion

Dr. Allison Brager provides a comprehensive overview of the science and practice of sleep resilience and efficiency. The key takeaway is that while genetics largely determines our baseline sleep needs and chronotype, we can significantly improve sleep quality and maintain performance under challenging conditions by understanding and working with our biology. This involves establishing strong, consistent daily routines (zeitgebers) that anchor our circadian rhythms, using tools like caffeine, light, and specific supplements strategically, and adopting practices like appropriate napping or gradual sleep extension when needed. While short-term resilience allows us to push through occasional poor sleep, chronic sleep deprivation carries significant health and performance costs that cannot be entirely overridden by willpower or stimulants. Ultimately, achieving effective sleep requires a personalized approach grounded in biological principles and consistent habits.