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Nap

A nap is a short period of sleep, typically lasting from 10 to 30 minutes and occurring during the daytime as a supplement to the primary nocturnal sleep period, aimed at restoring alertness and mitigating fatigue.^[1] Naps provide several cognitive and physiological benefits, including enhanced memory consolidation, improved executive functioning, and boosted alertness and mood, particularly for individuals experiencing sleep deprivation or daytime drowsiness.^[2] Research demonstrates that naps of 60-90 minutes can outperform caffeine in improving verbal recall, while longer naps (60-90 minutes) may facilitate perceptual learning comparable to a full night's rest.^[3] These effects stem from the brain's ability to process information and reduce sleep pressure during naps, leading to better performance in tasks requiring logical reasoning and motor skills.^[3] However, napping carries potential risks, especially when excessive or poorly timed; naps longer than 30 minutes or exceeding one hour daily have been associated with disrupted nighttime sleep, increased grogginess upon waking (known as sleep inertia), and elevated risks of cardiovascular conditions like high blood pressure, diabetes, and heart disease. Additionally, recent research as of 2023 has associated habitual long naps with higher risks of obesity and metabolic syndrome.^[4]^[5]^[6] Studies also suggest that habitual long naps may mask underlying sleep disorders or contribute to inflammation markers, though evidence remains mixed.^[3] To maximize benefits and minimize drawbacks, experts recommend short naps of 10-20 minutes taken early in the afternoon (ideally before 3 p.m.) in a quiet, dark environment, avoiding naps close to bedtime that could interfere with nocturnal sleep consolidation.^[4] Regular nappers tend to experience fewer adverse effects and greater performance gains compared to occasional ones.^[3] Culturally, napping practices vary widely; in Mediterranean countries like Spain, the traditional siesta—an afternoon rest—has long been viewed as healthful, including for digestion, and for productivity, though modern work schedules increasingly discourage it.^[7] In contrast, many Western societies prioritize continuous wakefulness, with about one-third of U.S. adults napping daily despite limited cultural emphasis on the practice.^[3] Across regions, napping frequency influences perceptions, with higher prevalence in warmer climates or among shift workers where it serves as a fatigue countermeasure.^[2]

Definition and Fundamentals

What is a Nap

A nap is defined as a short period of sleep occurring outside the primary nocturnal sleep episode, typically lasting 10 to 30 minutes during typical wakeful hours.^[1]^[8] This distinguishes it from the main nighttime sleep, which constitutes the bulk of an individual's daily rest, as well as from microsleeps—brief, involuntary lapses into sleep lasting mere seconds that often signal extreme fatigue.^[9] Naps serve as adjunctive rest episodes, interrupting the diurnal wake period without replacing the core sleep cycle.^[10] The term "nap" originates from the Old English verb hnappian, meaning "to doze" or "sleep lightly," with roots traceable to the Middle English nappen around the 14th century.^[11] Naps differ from culturally specific practices like the siesta, a traditional early-afternoon rest often following a midday meal in regions such as Spain and Latin America, which may extend beyond a brief doze to include leisure.^[12] In contrast, a power nap refers to a modern, deliberate short sleep—usually 10 to 20 minutes—aimed at rapid restoration, popularized in productivity literature since the late 20th century.^[13]^[14] Fundamentally, naps occur outside primary sleep cycles and align with diurnal rhythms, such as the natural post-lunch dip in alertness driven by circadian influences.^[2]

Physiological Basis

Napping involves a progression through sleep stages that mirrors aspects of nocturnal sleep but is typically abbreviated. Short naps, lasting 10-30 minutes, predominantly encompass light non-rapid eye movement (NREM) sleep, specifically stages N1 and N2. Stage N1 represents the transition from wakefulness, characterized by theta waves and reduced muscle activity, while stage N2 features sleep spindles and K-complexes on electroencephalogram (EEG), promoting memory consolidation without deeper immersion. Longer naps exceeding 30 minutes carry the risk of entering stage N3, or slow-wave sleep (SWS), marked by delta waves (0.5-4 Hz), or even rapid eye movement (REM) sleep, which can complicate arousal due to physiological inertia.^[1]^[15] The physiological propensity for napping is governed by the interaction of homeostatic sleep drive (Process S) and circadian rhythms (Process C), as outlined in Borbély's two-process model of sleep regulation. Process S accumulates during wakefulness, reflecting the buildup of sleep need through increased EEG slow-wave activity, and dissipates during sleep, including naps, to restore balance. Process C, driven by the suprachiasmatic nucleus, modulates alertness with a post-lunch dip in the early afternoon (around 1-4 p.m.), when sleep propensity peaks due to reduced circadian promotion of wakefulness. This interplay facilitates nap initiation during the daytime nadir, where Process S pressure can override residual wake-promoting signals, though naps partially discharge Process S, potentially affecting subsequent nighttime sleep architecture.^[16]^[17] Neurochemically, napping promotes restoration by clearing accumulated adenosine, a byproduct of neuronal ATP metabolism that builds during prolonged wakefulness and inhibits arousal via A1 receptors. During sleep, including naps, adenosine levels decline as it is reconverted to ATP, alleviating sleep pressure and enhancing vigilance upon awakening, particularly in light NREM stages. Concurrently, delta wave activity in stage N3, if reached, underscores restorative processes, with high-amplitude slow oscillations facilitating synaptic homeostasis and waste clearance in the brain. Hormonally, the afternoon circadian dip in cortisol—a glucocorticoid that sustains wakefulness—eases nap onset, while early melatonin secretion from the pineal gland, triggered by dim light cues, can emerge during naps in darkness, further signaling sleep readiness in approximately 40% of individuals.^[18]^[19]^[15]^[20]^[21]

Types and Classifications

By Duration

Naps are commonly categorized by their duration, which influences their physiological effects, duration of benefits, and potential for sleep inertia—the grogginess upon waking. Short naps typically last 5 to 10 minutes and provide a rapid boost in alertness without entering deeper sleep stages, making them suitable for quick refreshment in high-demand scenarios like brief work breaks.^[22] These micro-naps, sometimes combined with caffeine intake in a "coffee nap" protocol, enhance vigilant attention and reduce subjective fatigue shortly after waking, as demonstrated in a pilot study where participants experienced improved performance compared to placebo conditions.^[23] Moderate naps, ranging from 10 to 30 minutes, are often recommended as power naps that avoid slow-wave sleep, thereby minimizing sleep inertia while optimizing cognitive refreshment for several hours. A seminal 1995 NASA study on pilots found that a 26-minute nap improved job performance by 34% and alertness by up to 54%, with benefits persisting for over two hours post-nap.^[24] This duration aligns with light sleep stages, promoting immediate recovery without the drawbacks of deeper sleep interruption.^[22] Longer naps of 30 to 90 minutes allow for a more complete sleep cycle, potentially including slow-wave and REM sleep for enhanced physical and mental restoration, though they carry a greater risk of sleep inertia if awakening occurs mid-cycle. Research indicates that 90-minute naps can limit inertia by concluding at the end of a cycle, supporting sustained performance in extended wakefulness, but shorter durations within this range may still induce temporary grogginess resolved within 30 minutes.^[25] Such naps are better suited for scenarios permitting recovery time, like midday rests in shift work.^[26]

By Purpose

Naps can be categorized by their underlying purpose, which reflects the motivation driving the behavior and influences their timing and expected outcomes. This classification, originally proposed in early sleep research, divides naps into three primary types: restorative, prophylactic, and appetitive.^[27] Restorative naps are taken in response to accumulated sleep debt or subjective fatigue, aiming to replenish energy and mitigate the effects of prior sleep restriction. These naps are particularly prevalent among shift workers, such as nurses on night shifts, where irregular schedules lead to chronic sleep deficits; studies show that such naps improve vigilance and cognitive function during extended work periods by partially compensating for lost nighttime sleep.^[28] A well-known example is the siesta tradition in Mediterranean countries like Spain, where an afternoon nap serves as a restorative break following the midday meal to recover from morning exertions in warmer climates.^[7] Prophylactic naps, in contrast, are scheduled preemptively to build a buffer against anticipated sleep loss or fatigue, rather than reacting to it. This type is common in high-stakes environments like military operations and aviation, where personnel take naps before prolonged duties to sustain alertness; for instance, Federal Aviation Administration research indicates that pre-duty naps significantly attenuate performance declines during night shifts. NASA recommends similar short naps for astronauts to prepare for mission demands in space, where sleep opportunities are limited and irregular.^[29]^[30] Appetitive naps are motivated by enjoyment or habit rather than necessity, often occurring spontaneously for pleasure without underlying fatigue. These may manifest as casual post-lunch dozing, driven by natural circadian dips or relaxation; experimental studies differentiate them from restorative naps by their lack of sleep debt recovery intent, noting they can still enhance mood when taken by well-rested individuals.^[31]

Benefits of Napping

Cognitive Enhancements

Napping has been shown to enhance declarative memory consolidation, particularly through the incorporation of slow-wave sleep (SWS), which facilitates the replay of hippocampal activity associated with recently learned information. During such naps, neural replay mechanisms in the hippocampus strengthen episodic and factual memories by reactivating learning-related patterns, a process analogous to that observed in nocturnal sleep but achievable in brief daytime episodes.^[32] For procedural memory, which involves skills and motor sequences, naps promote consolidation by stabilizing performance gains post-learning, as demonstrated in tasks requiring finger-tapping sequences where a 90-minute nap led to overnight improvements comparable to full-night sleep.^[33] Studies indicate that short naps of 20-30 minutes can significantly improve fact retention and learning outcomes, with benefits observed in declarative tasks such as vocabulary acquisition. In a 2008 experiment, participants who took a brief nap after learning word pairs exhibited superior recall compared to those who remained awake, highlighting the role of even ultra-short sleep episodes (as little as 10 minutes) in stabilizing new verbal information against forgetting.^[34] These enhancements typically range from 20-30% better retention rates for factual material, underscoring naps as an effective tool for bolstering educational learning without extended rest periods.^[35] Naps also facilitate problem-solving by promoting insight through diffuse thinking modes during sleep-dependent restructuring of memory representations. In a seminal 2004 study using a number reduction task, participants who napped after initial training were over twice as likely to discover hidden rules (40% insight rate) compared to those who stayed awake (20%), attributing this to SWS-mediated reorganization of implicit knowledge into explicit solutions.^[36] At the neural level, these cognitive enhancements arise from increased synaptic plasticity during nap-induced SWS, where slow oscillations downscale synaptic strengths to prevent overload while strengthening relevant connections, as per the synaptic homeostasis hypothesis.^[37] Additionally, naps activate the glymphatic system, enhancing clearance of metabolic waste like amyloid-beta from the brain, which supports memory by maintaining neural efficiency and reducing interference from accumulated toxins. A 2023 Mendelian randomization study further suggests a causal association between habitual daytime napping and larger total brain volume, potentially benefiting cognitive function in older adults.^[38]

Alertness and Performance

Napping serves as an effective countermeasure to sleep deprivation by reducing fatigue and enhancing vigilance. Short naps, particularly those lasting 10 minutes, can restore alertness and reaction times to levels comparable to well-rested states following restricted nocturnal sleep, thereby mitigating the cognitive impairments associated with acute sleep loss.^[39] This restoration occurs through the alleviation of accumulated sleep pressure, allowing for improved sustained attention without the need for extended recovery sleep.^[40] In terms of performance metrics, napping has demonstrated tangible improvements in simulated tasks requiring high operational efficiency. For instance, a brief nap before a monotonous driving simulation significantly reduced subjective sleepiness and lane-drifting errors, with studies indicating up to a 50% decrease in performance lapses compared to no-nap conditions.^[41] These enhancements in reaction time and error rate underscore napping's role in bolstering immediate executive function under fatigue-inducing scenarios.^[42] Workplace applications further highlight napping's utility for boosting productivity in repetitive or vigilance-demanding roles. Meta-analyses of controlled trials reveal that brief midday naps increase output in monotonous tasks by improving alertness and reducing error rates, with effects persisting for up to 155 minutes post-nap.^[43] Such interventions are particularly beneficial for shift workers, where planned naps have been shown to counteract circadian dips in performance.^[28] Recent meta-analyses (2023-2024) also show that daytime napping improves physical performance in athletes and active individuals, reducing fatigue, enhancing mood, and improving psychophysiological measures following normal nighttime sleep.^[44]^[45] However, the benefits of napping on alertness and performance are time-sensitive, typically peaking between 30 and 60 minutes after awakening to allow dissipation of any transient grogginess.^[46] Beyond this window, while residual gains may endure, the most pronounced improvements in operational efficiency occur shortly after this optimal recovery period.^[47]

Health and Therapeutic Applications

However, longer naps of 60 minutes or more have been linked to increased cardiovascular risk, with a meta-analysis of 21 studies reporting a 1.82-fold higher rate of cardiovascular disease for extended daytime napping.^[48] Recent evidence (as of 2024) indicates that habitual napping overall, particularly durations of 30 minutes or more, is associated with elevated risks of cardiovascular disease.^[49] In terms of immune function, napping supports cytokine regulation and enhances recovery processes. Short naps reverse elevated levels of the pro-inflammatory cytokine interleukin-6 (IL-6) induced by sleep restriction, thereby mitigating inflammatory responses and promoting immune homeostasis.^[50] Additionally, a 30-minute nap combined with recovery sleep improves leukocyte counts, bolstering innate immune responses and aiding overall recovery from stressors that compromise immunity.^[51] These effects suggest napping facilitates faster immune restoration, potentially accelerating recovery from acute illnesses by reducing chronic inflammation.^[2] Napping serves therapeutic roles in managing certain sleep disorders and occupational fatigue. For narcolepsy, scheduled naps of 15-20 minutes, one to three times daily, are prescribed to alleviate excessive daytime sleepiness and reduce reliance on stimulants, often requiring workplace accommodations.^[52] In shift work sleep disorder, strategic naps before or during shifts decrease fatigue and enhance alertness, as evidenced by improved reaction times in controlled trials.^[53] NASA incorporates napping protocols in space missions to counter fatigue, recommending proactive short naps (10-40 minutes) in controlled environments to optimize performance during extended wakefulness, with benefits lasting up to several hours.^[54]

Risks and Drawbacks

Sleep Inertia

Sleep inertia refers to the transitional state of grogginess, disorientation, and reduced alertness that occurs immediately upon awakening from sleep, often accompanied by impaired cognitive and motor performance.^[55] Common symptoms include slower reaction times, decreased vigilance, confusion, and a strong desire to return to sleep, which can temporarily hinder decision-making and task execution.^[56] These effects typically last 15 to 60 minutes but can persist up to several hours in severe cases, with the most pronounced impairment occurring in the first few minutes after waking.^[57] The phenomenon is particularly intense when arousal happens during deep non-rapid eye movement (NREM) sleep stages, exacerbating the disorientation compared to lighter sleep phases.^[58] The primary cause of sleep inertia is the abrupt interruption of sleep processes, especially when awakening from slow-wave sleep (SWS), the deepest stage of NREM sleep characterized by high-amplitude delta brain waves.^[59] During SWS, the brain's arousal systems are suppressed, and sudden waking disrupts the gradual transition to full wakefulness, leading to a temporary mismatch between physiological readiness and environmental demands.^[55] This understanding stems from a seminal review highlighting how SWS involvement prolongs the period of lowered arousal and performance decrement post-awakening.^[60] Several factors influence the severity of sleep inertia, notably nap duration and preparatory interventions. Naps exceeding 30 minutes are more likely to induce SWS, thereby increasing the intensity and duration of inertia compared to shorter naps that remain in lighter sleep stages.^[55] Conversely, consuming caffeine immediately before a nap can mitigate these effects; the stimulant's peak absorption aligns with nap's end, counteracting residual sleepiness and eliminating performance deficits upon waking.^[61] Sleep inertia is commonly measured using subjective and objective tools, such as the Karolinska Sleepiness Scale (KSS), a validated nine-point questionnaire assessing perceived alertness, which shows elevated scores immediately post-nap indicative of heightened grogginess.^[62] Objective assessments, like the Psychomotor Vigilance Test (PVT), reveal performance impairments equivalent to those from extended sleep deprivation, with notable increases in reaction time lapses in the initial post-awakening period, underscoring the scale of cognitive disruption.^[55]

Health and Sleep Disruption Risks

Habitual napping, particularly late in the afternoon, can interfere with nighttime sleep by reducing the homeostatic sleep drive, leading to difficulties falling asleep and overall poorer sleep quality.^[2] Studies have shown that frequent or late naps are associated with increased sleep fragmentation, longer sleep onset latency, and reduced sleep efficiency during the night.^[63] For instance, naps occurring after mid-afternoon may delay bedtime and contribute to insomnia symptoms by partially satisfying the accumulated sleep need earlier in the day.^[64] A 2024 meta-analysis of cohort studies found that napping for more than 30 minutes was associated with an 8-21% increased risk of type 2 diabetes mellitus, independent of nighttime sleep duration.^[65] Similarly, prolonged napping poses cardiovascular strain, particularly in individuals with predisposing factors, as it correlates with greater risks of hypertension, heart failure, and overall cardiovascular disease events. Research indicates that naps longer than 30 minutes were associated with a 23% higher risk (HR 1.23, 95% CI 1.14-1.33) of cardiovascular outcomes in older adults.^[66] Additionally, a 2024 meta-analysis found that daytime napping is associated with increased risks of all-cause mortality and cardiovascular disease mortality.^[67] Excessive napping often serves as an indicator of underlying health conditions rather than a benign habit. In particular, frequent or extended daytime sleep is associated with depression, where it may reflect disrupted circadian rhythms or low mood-related fatigue, and obstructive sleep apnea, which fragments nighttime rest and promotes daytime somnolence. Health organizations, including the American Heart Association, caution that habitual napping beyond short durations can exacerbate these issues and recommend monitoring for such patterns to address potential comorbidities.^[68]

Napping Across Life Stages

In Children and Adolescents

Napping plays a crucial developmental role in children and adolescents by supporting brain growth and cognitive processes. During early childhood, naps facilitate memory consolidation, which is essential for learning and neural development. Studies indicate that naps enhance the consolidation of newly acquired information, allowing the immature hippocampus in young children to process memories effectively. For toddlers aged 1 to 2 years, the American Academy of Sleep Medicine recommends 11 to 14 hours of total sleep per day, including naps that typically total 1 to 3 hours, often split into one or two sessions to promote optimal health and brain maturation.^[69]^[70]^[71] As children transition to school age, napping patterns shift, with most phasing out regular naps by adolescence, though short naps can still provide benefits for academic performance. Preschoolers aged 3 to 5 years require 10 to 13 hours of total sleep, including naps of about 45 minutes to 1.5 hours, but by ages 6 to 12, the need diminishes to 9 to 12 hours without routine napping. A 2019 study of school-aged children found that those who napped 30 to 60 minutes at least three times a week demonstrated higher academic achievement, alongside improved self-control and reduced behavioral problems, suggesting that occasional short naps can aid focus and learning in older children and adolescents who may face sleep deprivation from school demands. Adolescents, in particular, benefit from brief 20- to 30-minute naps to bolster memory encoding and performance on complex tasks, though habitual long naps are uncommon after age 5.^[69]^[72] However, excessive or prolonged napping beyond age-appropriate needs carries risks, including links to behavioral issues and poorer cognitive outcomes. Research shows that more frequent naps than expected for age in children aged 8 to 38 months are associated with lower receptive vocabulary and executive function scores, potentially indicating underlying sleep disruptions. Longitudinal studies further connect daily napping in early childhood to increased internalizing and externalizing behaviors later on, emphasizing that napping is optimal until around age 5, after which over 94% of children naturally cease. In daycare settings, structured nap routines—such as consistent timing, dark and quiet environments, and individual cribs—help maintain healthy patterns for young children, aligning with guidelines from pediatric organizations to support rest without excess.^[73]^[74]^[75]^[76]

In Adults and Elderly

In working-age adults, napping occurs regularly for about 30% of individuals more than once per week, often as a response to daily demands such as occupational fatigue.^[77] This pattern is particularly pronounced among those in high-stress environments, where a 2024 survey of over 1,000 full-time workers revealed that 33% nap weekly during work hours, primarily to alleviate sleep loss from job-related stressors affecting nearly 80% of respondents.^[78] Such habits reflect adaptive strategies to maintain alertness amid irregular schedules, though frequency varies by employment type, with remote and hybrid workers reporting higher rates than in-office employees.^[79] Among older adults, daytime napping becomes more common, with up to 50% engaging regularly, largely due to fragmented nighttime sleep caused by age-related changes in sleep architecture and comorbidities.^[80] Short naps, typically 30 to 90 minutes, support cognitive function by enhancing memory consolidation and reducing fatigue, as evidenced by improved word recall and brain activity in studies of community-dwelling seniors.^[81] In contrast, prolonged naps exceeding 90 minutes often indicate underlying issues like frailty or preclinical dementia, correlating with accelerated cognitive decline and higher risks of adverse health outcomes in longitudinal analyses of nursing home residents.^[82]^[83] Gender differences influence napping behaviors and outcomes, with men reporting higher frequency—such as 38% versus 31% of women taking naps on a typical day, according to a 2009 U.S. survey—potentially due to variations in work patterns and sleep needs.^[84] Women, who nap less often, may derive greater cognitive benefits, including enhanced source memory retention following daytime sleep, as shown in experimental research comparing declarative memory performance across sexes.^[85] Midlife napping habits play a pivotal role in long-term cognitive trajectories, where moderate afternoon naps under 30 minutes combined with 6-7 hours of nighttime sleep are linked to preserved brain health and reduced dementia risk in later years.^[86] Conversely, excessive or irregular napping during midlife associates with poorer brain integrity and faster cognitive aging, underscoring the importance of establishing balanced sleep routines earlier in adulthood to mitigate degenerative changes.^[87]

Practices and Recommendations

Optimal Techniques

Optimal napping timing aligns with the body's natural circadian rhythm, particularly the post-lunch dip in alertness that typically occurs in the early afternoon. For most individuals maintaining a standard sleep-wake schedule, the ideal window is between 1 p.m. and 3 p.m., as this period coincides with decreased vigilance and allows for restorative rest without significantly disrupting nighttime sleep.^[1]^[64] Experts recommend avoiding naps within eight hours of bedtime to prevent interference with the ability to fall asleep at night and maintain consolidated sleep.^[1] Creating an conducive environment enhances nap quality by minimizing disruptions and promoting rapid sleep onset. A dark, quiet space is essential, as light and noise can inhibit melatonin production and prolong time to sleep; tools like eye masks and white noise machines or fans effectively block external stimuli.^[88] The room temperature should be maintained between 15°C and 19°C (60°F to 67°F), a range that supports thermoregulation during light sleep stages without causing discomfort from overheating or chilling.^[89]^[88] Specific techniques can optimize nap efficacy for different needs. The coffee nap, involving consumption of caffeine (typically 100-200 mg, equivalent to a standard cup of coffee) immediately followed by a 20-minute nap, leverages the adenosine-clearing effects of caffeine during the brief sleep period to heighten post-nap alertness more than either alone.^[90]^[91] For those with chronic fatigue, splitting naps—dividing total daytime rest into shorter sessions, such as two 15-20 minute bouts—can reduce homeostatic sleep pressure and alleviate symptoms by allowing intermittent recovery without deep sleep inertia.^[92]^[93] Personalization ensures naps suit individual circadian patterns and lifestyle demands, with tracking tools aiding adjustment. Sleep tracking apps, such as Sleep Cycle or RISE, monitor nap duration, quality, and timing via smartphone sensors or wearables, enabling users to identify optimal personal schedules based on real-time data.^[94] According to 2024 guidelines from the Sleep Foundation, most adults benefit from naps under 30 minutes to boost alertness while avoiding grogginess upon waking.^[1]

Cultural and Societal Contexts

Napping has deep historical roots, with evidence of midday rest practices in ancient civilizations. Historical accounts suggest biphasic sleep patterns, including short daytime rests, were practiced in ancient Egypt, as described by later writers such as the Roman historian Plutarch.^[95] Similarly, in ancient Rome, Romans routinely observed a midday siesta after morning activities, using this time for rest and reflection to counter the day's heat and natural energy dips before evening meals.^[96] These practices persisted into the pre-industrial era but declined in Western societies during the 19th and 20th centuries due to industrialization, which imposed rigid nine-to-five schedules and artificial lighting, shifting sleep to a consolidated nighttime block and marginalizing daytime napping.^[97] Cultural attitudes toward napping vary widely across regions, reflecting local traditions and values. In Spain and much of Latin America, the siesta—a post-lunch nap lasting 20 to 30 minutes—remains a longstanding custom, originating from Roman influences and adapted to hot climates, where shops often close in the early afternoon for rest.^[12] In Japan, the practice of inemuri, or "sleeping while present," involves brief public naps, particularly in workplaces or on trains, and is viewed positively as a marker of dedication and exhaustion from hard work rather than laziness.^[98] In the 2020s, societal attitudes have evolved, particularly in professional settings. Companies like Google have implemented nap pods in offices since the mid-2010s, formalizing short rests to boost productivity, a trend that gained momentum amid growing recognition of sleep's role in performance.^[99] The COVID-19 pandemic further accelerated informal napping through remote work, with surveys indicating nearly half of home-based employees taking midday naps—twice the rate of office workers—due to flexible schedules and reduced commuting.^[100] Global disparities in napping acceptance highlight cultural divides. In Protestant-influenced Northern European and North American societies, the Protestant work ethic fosters a stigma against rest during work hours, equating it with idleness and prioritizing constant productivity over rejuvenation.^[101] Conversely, Mediterranean cultures, such as those in Spain, Greece, and Italy, embrace midday napping as a normative tradition tied to climate and lifestyle, while many Asian societies, including Japan and China, tolerate or encourage brief public rests as signs of diligence or necessity.^[102]

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