Napping in athletes: A scoping review

Abstract

<h2>Abstract</h2> <p>Sleep is the most potent recovery modality available to athletes, and napping — a brief daytime sleep episode — has attracted growing attention as a strategy to supplement nocturnal sleep and offset the cumulative sleep debt that characterizes high-performance training environments. This scoping review by Lastella and Halson (2021) synthesizes available evidence on napping practices, prevalence, and performance effects in athletic populations, drawing on data from 36 studies involving elite and sub-elite athletes across a diverse range of sports.</p> <p>The review identifies several key findings. First, elite athletes nap frequently, with a substantial proportion reporting regular daytime napping as part of their recovery routine. Second, short naps of 20-30 minutes produce significant improvements in cognitive function, reaction time, and subjective alertness, with these benefits most pronounced in athletes who carry a sleep debt [1, 2]. Third, nap duration critically influences the type of sleep stage entered, with naps exceeding 90 minutes risking entry into slow-wave sleep and producing sleep inertia (SI) — a transient period of grogginess and impaired performance upon waking [3].</p> <p>From a practical standpoint, the evidence supports 20-30 minute napping between training sessions and prior to competition as an effective, non-pharmacological <a href="/terms/ergogenic-aid/" class="term-link" data-slug="ergogenic-aid" title="ergogenic aid">ergogenic aid</a>. The optimal nap window appears to be early-to-mid afternoon (12:00-15:00), which aligns with the natural post-prandial dip in circadian alertness and minimizes interference with nocturnal sleep architecture.</p>

Introduction

<h2>Introduction</h2> <p>The relationship between sleep and athletic performance is now well-established: chronic sleep restriction impairs reaction time, cognitive processing, mood, and physical performance, while sleep extension produces measurable improvements across these same domains [4, 5]. Yet despite this clear <a href="/terms/dose-response-relationship/" class="term-link" data-slug="dose-response-relationship" title="dose-response relationship">dose-response relationship</a>, many high-performance athletes chronically fail to achieve recommended sleep durations (7-9 hours per night for adults). Early morning training sessions, late-night competition, travel across time zones, and the anxiety associated with performance evaluation all conspire to fragment or curtail nocturnal sleep, creating a pervasive state of sleep debt within athletic populations.</p> <p>Napping represents an accessible and effective strategy to partially offset this deficit. Unlike many recovery modalities that require specialized equipment, facilities, or professional administration, napping demands only a quiet space, a brief period of time, and the ability to fall asleep on demand — a skill that experienced nappers can cultivate with practice. These characteristics make napping uniquely scalable for elite sport settings where the recovery window between morning and afternoon training sessions may be two to four hours.</p> <p>The scientific literature on napping in athletes has grown substantially over the past decade, transitioning from isolated case reports and descriptive surveys to controlled experimental designs examining specific performance outcomes. Researchers have investigated napping's effects on sprint speed, jump power, psychomotor vigilance, technical skills, and decision-making — outcomes directly relevant to competitive athletic performance [6].</p> <p>The scoping review framework employed by Lastella and Halson (2021) is particularly appropriate for this emerging field, as it maps the available evidence without the restrictive inclusion criteria of a <a href="/terms/systematic-review/" class="term-link" data-slug="systematic-review" title="systematic review">systematic review</a>, allowing the breadth of the napping literature to be characterized and gaps identified. This review provides the most comprehensive overview of athletic napping practices and outcomes to date, and its findings have direct implications for athlete sleep management protocols.</p>

Evidence Review

<h2>Evidence Review</h2> <h3>Napping Prevalence in Athletes</h3> <p>The review first establishes the prevalence of napping among athletes, a necessary foundation for understanding the population being studied. Survey data from elite athlete cohorts indicate that 60-80% of athletes report napping at least occasionally, with a significant subset napping daily or on most <a href="/terms/training-frequency/" class="term-link" data-slug="training-frequency" title="training days">training days</a> [7]. This prevalence substantially exceeds that of the general population, suggesting that athletes either have a greater need for daytime sleep (due to training load and sleep debt) or have been culturally conditioned to view napping as a legitimate recovery practice.</p> <p>Team sports athletes nap more frequently than individual sport athletes, possibly because team training schedules create more predictable mid-day gaps and because the culture of team sport programs may normalize the practice. Athletes who consistently sleep fewer than 7 hours at night nap more frequently and derive more substantial performance benefits from napping, supporting the sleep debt hypothesis as a primary driver of napping efficacy.</p> <h3>Cognitive and Perceptual Benefits</h3> <p>The most robust evidence for napping benefits relates to cognitive and perceptual outcomes. Studies employing psychomotor vigilance tasks (PVT), choice reaction time tests, and simulated sport-specific decision-making scenarios demonstrate that 20-30 minute naps produce:</p> <ul> <li>Significant reduction in PVT reaction time (6-12% improvement) [8]</li> <li>Improved accuracy on decision-making tasks</li> <li>Enhanced subjective alertness and reduced sleepiness</li> <li>Improved mood state (reduced fatigue, increased vigor on Profile of Mood States measures)</li> </ul> <p>These effects are most pronounced when testing occurs within 1-3 hours of nap termination and when athletes entered the nap in a state of partial sleep deprivation [1].</p> <h3>Physical Performance Effects</h3> <p>Evidence for napping-induced improvements in physical performance metrics is more variable. Several studies demonstrate significant improvements in sprint speed, jump height, and short-duration power output following napping compared with no-nap control conditions [9, 10]. However, effect sizes are generally small (d = 0.2-0.4), and the relationship appears mediated by the degree of prior sleep restriction — athletes sleeping optimally at night show minimal physical performance gains from napping.</p> <p>A critical confounding factor is time-of-day effects: many studies test performance in the afternoon, when circadian performance peaks naturally, potentially confounding nap-specific effects with time-of-day advantages [11].</p> <h3>Sleep Inertia: The Duration Caveat</h3> <p>A crucial practical consideration is sleep inertia (SI) — the period of transient cognitive impairment and subjective grogginess that follows awakening from sleep. SI duration and severity depend on the sleep stage from which awakening occurs: awakening from lighter sleep stages (N1, N2) produces minimal SI, while awakening from slow-wave sleep (N3) or REM sleep produces pronounced SI lasting 15-30 minutes [3].</p> <p>Naps of 20-30 minutes typically remain in N1 or N2 sleep, minimizing SI risk. Naps of 60-90 minutes risk transitioning into N3 sleep mid-cycle, creating substantial SI risk. Naps of approximately 90 minutes can encompass a complete sleep cycle, allowing a return to lighter sleep stages before awakening — potentially making them viable for athletes with more than 2 hours available before performance demands resume.</p>

Discussion

<h2>Discussion</h2> <h3>The Sleep Debt Framework</h3> <p>The most coherent interpretation of the napping literature is that napping's benefits are primarily a function of correcting sleep debt rather than providing independent ergogenic effects on a well-rested athlete. This framing has important implications: it shifts the clinical priority from developing optimal napping protocols to ensuring that athletes achieve adequate nocturnal sleep in the first place. Napping should be viewed as a compensatory tool for a realistic reality — that athletes will inevitably face periods of suboptimal sleep due to competition schedules, travel, and performance anxiety — rather than an enhancement strategy to be deployed regardless of sleep status.</p> <p>This interpretation is consistent with the <a href="/terms/dose-response-relationship/" class="term-link" data-slug="dose-response-relationship" title="dose-response">dose-response</a> evidence: studies enrolling sleep-restricted athletes consistently show larger napping benefits than those using adequately rested participants. An athlete who sleeps 8-9 hours nightly and maintains good <a href="/terms/sleep-hygiene/" class="term-link" data-slug="sleep-hygiene" title="sleep hygiene">sleep hygiene</a> may derive minimal additional benefit from routine daytime napping, though napping remains a useful tool in preparation for events requiring maximal alertness.</p> <h3>Circadian Timing and Nap Placement</h3> <p>The timing of napping interacts with circadian biology in important ways. The post-prandial dip — a natural reduction in alertness occurring approximately 7-8 hours after waking — creates a physiological window of opportunity for napping in the early-to-mid afternoon [12]. Napping aligned with this window tends to produce faster sleep onset and better sleep quality than napping attempted at other times of day. Napping after 15:00-16:00 risks interference with the nocturnal sleep onset, as the homeostatic sleep pressure built during wakefulness may be partially discharged by the nap, delaying the natural evening sleep onset time.</p> <p>Chronotype influences optimal napping timing: morning chronotypes ("larks") may find their napping window earlier in the day, while evening chronotypes ("owls") may tolerate later afternoon napping with less interference with nocturnal sleep.</p> <h3><a href="/terms/caffeine/" class="term-link" data-slug="caffeine" title="Caffeine">Caffeine</a>-Nap Combinations</h3> <p>An intriguing evidence-based strategy is the "caffeine nap" — consuming caffeine (150-200 mg) immediately before a 20-minute nap. Caffeine's adenosine-blocking effects take 20-30 minutes to manifest, meaning that caffeine ingested immediately before napping does not disrupt the nap itself. Upon awakening, both the nap's restorative effects and the caffeine's alertness-promoting effects are simultaneously active, producing synergistic wakefulness effects that exceed either intervention alone [13]. This strategy is particularly useful in competitive contexts requiring rapid transition from rest to high performance.</p> <h3>Limitations of the Evidence Base</h3> <p>The scoping review methodology allows broad coverage but cannot determine the quality or certainty of evidence with the rigor of a <a href="/terms/systematic-review/" class="term-link" data-slug="systematic-review" title="systematic review">systematic review</a>. Several gaps in the literature deserve acknowledgment: studies predominantly involve male athletes, the controlled timing of pre-nap sleep is rarely standardized, and few studies assess napping's effects on training adaptation (as opposed to acute performance). The ecological validity of laboratory napping protocols is also uncertain — athletes forced to nap in unfamiliar laboratory environments may not replicate the outcomes achieved in familiar, comfortable settings [14].</p>

Practical Recommendations

<h2>Practical Recommendations</h2> <p>Based on the available evidence, the following guidelines are offered for integrating napping into athlete recovery and performance preparation programs.</p> <h3>Standard Nap Protocol</h3> <p>For most athletes in most circumstances, a 20-30 minute nap between training sessions is the optimal starting point. This duration: - Remains predominantly in N1/N2 sleep stages, minimizing sleep inertia risk - Produces significant improvements in alertness, reaction time, and cognitive function - Is long enough to be restorative but short enough to accommodate most mid-day training gaps</p> <p>Athletes should establish a consistent nap routine in a quiet, dark, and temperature-controlled environment. Using eye masks and earplugs is recommended for athletes napping in shared or noisy environments. Setting an alarm for 30 minutes (allowing for 5-10 minutes of sleep onset time) provides a reliable framework.</p> <h3>Nap Timing</h3> <p>Target the early-to-mid afternoon window (12:00-15:00 hours) aligned with the natural post-prandial dip in circadian alertness. Avoid napping after 15:00-16:00 unless nocturnal sleep has already been compromised and performance demands require immediate alertness management. Early evening napping should generally be avoided.</p> <h3>Sleep Inertia Management</h3> <p>For athletes who experience significant sleep inertia upon waking from naps, strategies include: - Keeping nap duration to 20-25 minutes to minimize slow-wave sleep entry - Consuming <a href="/terms/caffeine/" class="term-link" data-slug="caffeine" title="caffeine">caffeine</a> (150-200 mg) immediately before napping for the "caffeine nap" synergy - Allowing 15-20 minutes post-nap before requiring peak performance - Engaging in light movement or cold water exposure to accelerate SI clearance</p> <h3>Duration Guidelines by Scenario</h3> <table> <thead> <tr> <th>Scenario</th> <th>Recommended Nap Duration</th> <th>Key Consideration</th> </tr> </thead> <tbody> <tr> <td>Standard recovery between sessions</td> <td>20-30 minutes</td> <td>Minimize sleep inertia</td> </tr> <tr> <td>Significant sleep debt (less than 6 h nocturnal)</td> <td>30-60 minutes</td> <td>Allow extra SI recovery time</td> </tr> <tr> <td>Pre-competition with 2+ hours available</td> <td>90 minutes (full cycle)</td> <td>Complete cycle avoids mid-cycle awakening</td> </tr> <tr> <td>Caffeine-nap protocol</td> <td>20 minutes + 150 mg caffeine pre-nap</td> <td>Synergistic alertness effect</td> </tr> </tbody> </table> <h3>Foundational Sleep First</h3> <p>Napping should complement, not replace, adequate nocturnal sleep. Athletes should prioritize achieving 8-9 hours of nocturnal sleep in consistent, dark, cool environments before investing significant effort in napping optimization. Napping is most effective as a compensatory tool during periods of unavoidable sleep restriction rather than as a chronic supplement to habitual short sleep [15].</p>