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05 August 2024

The Woman Who Helps Athletes Sleep: Stop Having Showers Just Before Bed! New Science! ‘Nappucino’ Phenomenon You Need To Know!

7Frameworks
15Insights

Frameworks in this episode

Insights & moments

The myth-busts, hot takes, explainers, and tools worth keeping.

Myth Buster· 3

Myth Buster57:30

Why Repeated Snoozing May Fragment Valuable Morning Sleep

Mah argues that repeatedly pressing snooze can fragment the final part of the night, when REM sleep is more common. She recommends setting the alarm for the actual wake time or reducing the habit to one short snooze, framing consolidated sleep as preferable to repeated awakenings and returns to lighter sleep.

  • Five-minute snoozes can repeatedly interrupt the final half hour
  • REM sleep is more prevalent in the early morning
  • Repeated waking may replace a consolidated REM period with wakefulness and lighter sleep
  • Mah suggests cutting down to one five-minute snooze if stopping immediately is difficult
  • The recommendation aims to protect learning and memory consolidation

I'm not a huge fan of the snooze

Dr. Cheri Mah · 57:30

you want to have as much as possible

Dr. Cheri Mah · 59:00
#snooze#rem sleep#alarm#sleep fragmentation
Myth Buster1:17:30

One Long Night Is Not the Same as Harmful Oversleeping

Mah distinguishes an occasional ten-hour night from observational links between habitual very long sleep and health conditions. She says grogginess after sleeping longer may reflect a shifted schedule, dehydration, or accumulated sleep loss, and separately urges people who snore to discuss possible sleep-apnea testing with a primary-care clinician.

  • An occasional long sleep does not by itself establish harm
  • Studies linking very long sleep with illness may be confounded by underlying conditions
  • A large shift in wake time can contribute to grogginess
  • Snoring is not always benign
  • Breathing pauses, gasping, choking, and unrefreshing sleep can warrant medical assessment
  • Mah estimates sleep apnea affects about 26% of adults aged 30 to 70

if you're snoring you should go talk with your primary care doctor

Dr. Cheri Mah · 1:19:30

you can also be a very fit healthy young individual

Dr. Cheri Mah · 1:22:00
#oversleeping#snoring#sleep apnea#medical assessment
Myth Buster1:27:30

Night Awakenings Can Be Normal—Until They Become Persistent

Mah says a brief awakening, such as using the bathroom and returning to sleep within five to ten minutes, can be a normal part of sleep-stage transitions. She recommends more attention when awakenings are frequent over multiple weeks, impair daytime function, or occur with signs such as snoring or breathing pauses.

  • Healthy sleep does not require remaining consciously asleep all night
  • Some awakenings occur during transitions between sleep stages
  • Wearables may show awakenings the person does not remember
  • Noise, alcohol, caffeine, stress, a bed partner, or sleep apnea may contribute
  • Persistent or impairing awakenings should be discussed with a clinician

Awakenings actually can be very normal

Dr. Cheri Mah · 1:27:30

there's a number of ways reasons why you can awaken at nighttime

Dr. Cheri Mah · 1:28:30
#awakenings#sleep cycles#insomnia#sleep apnea

Explainer· 6

Explainer10:30

What Changed When Basketball Players Extended Sleep

Mah describes a study in which a men's basketball team was encouraged to spend nine to ten hours sleeping for five to seven weeks. She reports improvements in free throws, three-point shots, reaction time, and sprint time, while describing the findings as evidence that sleep extension may affect performance.

  • The study followed players across five to seven weeks
  • Sleep was measured with actigraphy and self-report
  • Mah reports roughly 90 extra minutes of sleep compared with baseline
  • Reported outcomes included 9% better shooting and 12% faster reaction time
  • The study associated sleep extension with a 4% faster standardized sprint

we saw a 9% Improvement in free throws

Dr. Cheri Mah · 11:30

we saw a 12% faster reaction time

Dr. Cheri Mah · 11:30
#sleep research#basketball#performance#reaction time
Explainer14:00

Why West Coast Teams May Gain a Night-Game Advantage

Mah discusses schedule-based research and a separate Monday Night Football finding as evidence that body-clock timing may influence team outcomes. She says West Coast teams can enter night games with their internal clock closer to a late-afternoon performance window, but the transcript does not establish schedule as the only cause of winning.

  • Mah says her NBA schedule project predicted high-risk losses with 76% to 86% accuracy across three seasons
  • The project intentionally did not account for team strength
  • She cites a separate 25-season finding involving West Coast teams and betting spreads
  • She attributes the proposed advantage to a roughly 4 p.m. to 8 p.m. body-clock window
  • Travel direction matters less in her example than the team's internal time during the game

I was 76 to 86% correct

Dr. Cheri Mah · 14:30

performance is enhanced in the late afternoon to evening around 4: to 8:00

Dr. Cheri Mah · 16:00
#circadian rhythm#nba#travel#performance
Explainer39:30

How Sleep Loss Can Erode Decisions and Reaction Time

Mah says insufficient sleep is associated with poorer emotional regulation, slower reactions, more cognitive errors, and weaker judgment. The host adds his personal practice of avoiding major decisions when underslept, while his Jeff Bezos example is explicitly framed as a remembered claim rather than independently established fact.

  • Mah links adequate sleep with faster reactions and fewer cognitive errors
  • She says underslept people may rely more on immediate emotional responses
  • The host reports becoming shorter with people after poor sleep
  • The host attributes a sleep-and-decisions view to Jeff Bezos but expresses uncertainty about the source
  • Mah cites the Challenger investigation as an example in which fatigue was identified among contributing decision factors

our emotional regulation is not the same if we're well rested versus if we're asleep deprived

Dr. Cheri Mah · 40:00

you're less likely to make cognitive errors

Dr. Cheri Mah · 42:30
#decision making#reaction time#emotions#fatigue
Explainer52:00

What Deep and REM Sleep Are Said to Support

Mah distinguishes light sleep, deep sleep, and REM sleep across recurring 90-to-120-minute cycles. She associates deep sleep and its growth-hormone pulse with muscle recovery, while linking REM more strongly to learning, memory, and skill consolidation; these are presented as broad functions rather than exclusive roles.

  • Sleep cycles recur roughly every 90 to 120 minutes
  • More deep sleep tends to occur earlier in the night
  • More REM sleep tends to occur in the early morning
  • Mah associates deep sleep with recovery and regeneration
  • She compares post-learning sleep to pressing a save button for memory

sleep as hitting that save button

Dr. Cheri Mah · 53:30

you have light stages of sleep then you have deep stages of sleep

Dr. Cheri Mah · 52:30
#rem sleep#deep sleep#memory#recovery
Explainer1:00:00

Chronotypes, Adolescence, and the Case for Later School Starts

Mah says evening and morning chronotypes reflect real natural tendencies, though many people sit between those poles. She adds that adolescent body clocks tend to shift later and cites evidence linking later school starts with better attendance, grades, mental-health outcomes, and fewer car accidents, without claiming that timing alone determines every student outcome.

  • Evening owls tend to sleep and work later
  • Morning larks tend to sleep and work earlier
  • Flexible schedules can help people align sleep with their chronotype
  • Adolescent sleep timing naturally shifts later
  • Mah says California changed school start times in response to a broader evidence base

there is a natural tendency for some to feel like they are evening owls

Dr. Cheri Mah · 1:01:00

students St want to an adolescence go to bed later and wake up later naturally

Dr. Cheri Mah · 1:03:30
#chronotype#adolescents#school#circadian rhythm
Explainer1:23:30

What the Evidence Suggests About Sleep and Injury Risk

Mah cites limited studies associating short sleep with greater injury risk, including one reporting about 1.7 times the risk below eight hours compared with more than eight. She stresses that the mechanism is not settled, then describes her early work showing more variable movement patterns after several days of insufficient sleep as one possible pathway.

  • Some adolescent-athlete studies link under six hours with more fatigue-related injuries
  • Another cited study reported roughly 1.7-fold higher injury risk below eight hours
  • Mah says the reason for the association remains unclear
  • Her biomechanics work found greater movement variability after insufficient sleep
  • Variable knee and hip coordination could be one possible risk pathway
  • She emphasizes that relatively few studies currently exist

there's just not that many studies that currently exist

Dr. Cheri Mah · 1:25:00

when you're not getting sufficient sleep for multiple days you have more more variability in your biomechanics

Dr. Cheri Mah · 1:24:30
#injury risk#athletes#biomechanics#sleep loss

Story· 2

Story18:30

Andre Iguodala's Reported Performance Shift After Better Sleep

Mah recounts working with Andre Iguodala after years of late-night gaming, short nighttime sleep, and long daytime naps. She says a third party measured substantial performance changes as his sleep increased, while presenting the case as an association within a broader career story rather than proof that sleep alone caused every outcome.

  • Iguodala reportedly wanted to extend his career and improve his sleep
  • His plan addressed naps, nutrition, environment, technology, and mental wind-down
  • Mah says his sleep rose from under seven hours to more than eight
  • She reports gains in shooting and points per minute alongside fewer fouls
  • Iguodala subsequently won Finals MVP and extended his career by about a decade

he says it changed everything for him

Dr. Cheri Mah · 21:00

extended his career for 10 years

Dr. Cheri Mah · 20:00
#andre iguodala#career longevity#basketball#case study
Story38:00

Ryan Jensen's Sleep-Apnea Diagnosis and NFL Comeback

Mah tells the story of NFL player Ryan Jensen, whose family noticed that he was not behaving like himself after he had been cut and placed on a practice squad. She says testing led to a sleep-apnea diagnosis and CPAP treatment, followed years later by a major contract and a Super Bowl win; the sequence is presented as his success story, not a controlled causal study.

  • Family observations prompted concern about a change in Jensen
  • Testing reportedly identified obstructive sleep apnea
  • CPAP was used to help keep his airway open during sleep
  • Four years later he signed a reported $42 million contract
  • Mah says Jensen has publicly credited treatment with making a major difference

he eventually was tested for sleep apnea

Dr. Cheri Mah · 38:00

very fragmented sleep through the night

Dr. Cheri Mah · 38:30
#sleep apnea#cpap#nfl#ryan jensen

Tool· 1

Tool1:12:00

Melatonin for Travel: Potential Use and Important Caveats

Mah says melatonin can sometimes help advance the body clock during travel, particularly when someone has used it before without problematic effects. She also warns about next-day grogginess and variable supplement contents, noting that US products are not regulated by the FDA in the way medicines are and that athletes may seek NSF Certified for Sport products.

  • Mah presents melatonin as a possible clock-shifting tool, not a universal requirement
  • She recommends caution if the user has not tried it before
  • Grogginess or sluggishness can occur after use
  • She cites research finding substantial variation between labels and measured contents
  • Sport-certified products provide athletes with additional testing safeguards

there are still side effects that to be wary of

Dr. Cheri Mah · 1:12:30

you don't always know what's actually in those supplements

Dr. Cheri Mah · 1:12:30
#melatonin#supplements#jet lag#travel

Takeaway· 3

Takeaway25:30

Move a Hot Shower Earlier Instead of Taking It at Bedtime

Mah recommends moving a hot shower or bath to roughly one to two hours before bed rather than taking it immediately before sleep. She explains that body temperature normally drops as sleep begins and says small studies suggest earlier heat exposure may support that decline, shorten sleep onset, and enhance deep sleep.

  • A hot shower temporarily raises core temperature
  • Core temperature normally falls around sleep onset
  • Mah recommends about 90 minutes of separation
  • She describes the evidence as coming from smaller studies
  • The adjustment may also serve as an evening relaxation cue

an hour and a half before you are planning to go to bed

Dr. Cheri Mah · 25:30

some smaller Studies have shown that that can help decrease the time to fall asleep

Dr. Cheri Mah · 26:00
#shower#temperature#sleep onset#deep sleep
Takeaway1:16:00

Keep Work Out of Bed to Protect the Sleep Association

Mah recommends reserving the bed for sleep and sex rather than computer work, phone use, or wakeful planning. She says repeated wakeful activity in bed can strengthen a learned association between bed and being awake; on sex itself, she notes anecdotal reports of better sleep but says strong research is limited.

  • Computer and phone work in bed can reinforce wakefulness
  • Wind-down and thought processing should occur outside bed
  • A moving or snoring bed partner can disrupt sleep
  • Some people report sleeping better after sex
  • Mah says the evidence on sex and sleep remains limited

sleep and sex are all that you want in bed

Dr. Cheri Mah · 1:16:00

I don't think there's a lot of great studies

Dr. Cheri Mah · 1:17:00
#bedroom#stimulus control#sex#sleep habits
Takeaway1:29:00

Alcohol Near Bedtime Is Linked With More Fragmented Sleep

Asked for a percentage effect, Mah declines to give one. She instead says studies of moderate-to-high alcohol consumption show an association with more awakenings and fragmented sleep, and recommends minimizing or eliminating alcohol near bedtime before an important performance day.

  • Mah does not provide a precise percentage effect
  • The claim is an association from moderate-to-high-consumption studies
  • The main reported effect is poorer sleep quality through fragmentation
  • Timing alcohol away from bedtime is her practical recommendation
  • Avoiding it may matter more before an important meeting or game

I don't know the specific statistics

Dr. Cheri Mah · 1:29:00

moderate to high consumption of alcohol that very much has a association with more fragmented sleep

Dr. Cheri Mah · 1:29:30
#alcohol#sleep quality#awakenings#performance