In a recent single-institution study of 628 collegiate athletes from 29 varsity teams, 42% experienced poor sleep quality (measured by the Pittsburgh Sleep Quality Index) and 51% reported high levels of excessive daytime sleepiness (assessed by the Epworth Sleepiness Scale). 13 Similarly, in the NCAA Growth, Opportunities, Aspirations and Learning of Students survey (GOALS), 5 less than 25% of collegiate athletes reported ≥8 hours of sleep on a typical night (online supplementary table 2 ). Poor sleep quality was also prevalent, as 19% of male and 23% of female respondents reported difficulty sleeping at least 8 of the past 30 days (see online supplementary table 3 for a breakdown by NCAA division). Moreover, 70% of male and 82% of female collegiate athletes reported a preference for more sleep. In sum, epidemiological data suggest that inadequate sleep quality and quantity could be targeted for improvement among collegiate athletes.

The American College Health Association’s annual National College Health Assessment (NCHA) survey includes information about sleep behaviour and allows researchers to aggregate results by students who self-identify as varsity athletes. 12 Among 14 134 collegiate athletes at NCAA member institutions, 61% reported daytime fatigue at least three or more days in the past week, and others reported consistent or more serious sleep difficulties ( table 1 ). These data are similar to those in non-athletes, 12 suggesting lack of sleep is endemic among all college students.

Better sleep is associated with greater academic success perhaps in part because acute sleep deprivation impairs cognitive performance and protracted insufficient sleep exacerbates mood disorders and distorts emotion regulation. 28 37–39 In general, students with better sleep (eg, >7 hours of night-time sleep, more consistent sleep schedules, lower levels of daytime sleepiness and less weekend ‘catch-up’ sleep) report higher grade point averages (GPAs). 28 37–39 Multiple single-institution prospective and cross-sectional studies have shown that insufficient, inconsistent and/or poor quality (non-restorative) sleep independently predict college students’ academic performance, even after accounting for other measures of achievement like standardised test scores. 28 37 In a study of 1845 undergraduates, those screening positive for possible sleep disorders were significantly more at risk for academic failure (GPA <2.0). 40 Among respondents in the 2009 ACHA-NCHA survey, sleep disturbances (early awakening, insufficient sleep or difficulty falling asleep) independently predicted poor academic performance, on par with high-risk drinking in its association with GPA and course completion. On average, each additional day per week a student reported experiencing sleep problems raised the probability of dropping a course by 10%. 41

In the 2018 American College Health Association (ACHA)-NCHA dataset, collegiate athletes with self-identified sleep problems were more than twice as likely to report feeling overwhelming anxiety, being so depressed it was difficult to function and considering suicide in the last 30 days compared with athletes who did not indicate sleep disturbance. 12 Prospective population studies demonstrate that disturbed sleep predicts development of anxiety and depression in adolescents. 32 In adults, anxiety and depression at baseline predict new cases of insomnia, and insomnia at baseline predicts new diagnoses of anxiety and depression 1 year later. 33 Similarly, treating insomnia improves depression and anxiety symptoms, and treating anxiety/depression improves insomnia. 34 In both students with depression and anxiety and healthy college students, better sleep is associated with improved mental wellness. 35 36

Sleep disturbances are clinically relevant for evaluation and treatment of mental health conditions in collegiate athletes. 6 27 28 The relationship between mental health and sleep quality are bidirectional and interdependent: poor sleep exacerbates mental health disorders and negative mood, and stress and mental health disorders lessen sleep quality and quantity. 29 The most commonly reported barrier to sleep among college students is perceived stress. 25 Among individuals with clinically relevant manifestations of depression and anxiety (25% of all collegiate athletes 30 ), sleep disturbances include difficulty with sleep initiation and maintenance, circadian rhythm dysregulation and insomnia or hypersomnia. 31

Adolescent athletes who reported sleeping <8 hours per night were 1.7 times more likely to have a musculoskeletal injury, 22 while sleeping >8 hours during weekday nights was associated with 61% lower odds of such an injury. 23 Similarly, a simultaneous increase in training load, training intensity and decreased hours of sleep resulted in a significantly higher risk of injury. 24 College students with poor quality sleep also report significantly more medical illness than those with near-ideal or ideal sleep (as determined by an aggregation of factors including sleep quality and duration). 25 One potential mechanism may be that increases in proinflammatory cytokines following sleep loss could promote immune system dysfunction. 26

As described in greater detail in a subsequent section, few studies have evaluated the effects of sleep extension on athletic performance. However, some studies have shown that serving accuracy, shooting accuracy and reaction time significantly improve in collegiate tennis and basketball players, respectively, following objectively measured sleep extension beyond 8 hours per day for several weeks. 19 20 Although regular exercise improves sleep quality, duration and efficiency, 21 the relationship between training loads, sleep and performance is complex and poorly understood. Sport-specific tasks and individual responses to training and sleep are likely different enough that optimising performance in athletes will require individualised approaches and further research.

Data are limited regarding the influence of sleep disturbance, sleep deprivation or circadian desynchrony on athletic performance. 8 9 14–16 Poor sleep is associated with delayed reaction time, increased perceived effort, fatigue, mood disturbance and reduced time to both exhaustion and task failure; however, it does not affect physiological markers of anaerobic, aerobic or power output. 8 14 17 Interestingly, sleep-deprived athletes may be able to execute or perform required sport-related tasks, but their task-related cognitive and psychological tolerance is diminished, thereby increasing perceived effort and somatic symptom reporting. 18 However, data on the overall physiological effects of sleep impairment and its dose–response relationship on endurance performance, anaerobic power, and sprint performance are conflicting. The data are derived from small samples with inconsistent methods to measure strength and performance. 8

When considering the use of consumer sleep technologies, ethical issues of privacy, including who has access to the sleep data, and informed consent are hurdles that need to be cleared. Any sleep-monitoring programmes should be voluntary for collegiate athletes and include sleep health and performance education. Coaches and medical personnel should thoroughly investigate data supporting the accuracy and functionality of any consumer sleep technologies before collegiate athletes use them.

One challenge in achieving collegiate athlete sleep health is determining the party responsible for screening, assessment and tracking of sleep beyond the athlete themselves. This group includes coaches, strength and conditioning specialists, team physicians, athletic trainers and psychologists. In some settings, strength and conditioning specialists are responsible for collecting subjective and objective collegiate athlete sleep data. They then relay the information and communicate with other clinicians/practitioners such as athletic trainers, team physicians and psychologists. Together, these professionals can provide the necessary support and expertise to the collegiate athlete to optimise his or her sleep health.

The emergence of consumer sleep technologies holds great promise for helping athletics departments better understand, and thus improve, collegiate athlete sleep. 42 43 Their ability to measure sleep in the collegiate athletes’ home environment over time provides a heretofore unattainable ecologically valid measure of sleep. Consumer sleep technologies can also identify problematic sleep that may indicate a sleep disorder. Despite the value of these technologies to coaches, team physicians and collegiate athletes, their use assisting medical providers in diagnosing sleep disorders is evolving and not yet mature. However, they can currently help collegiate athletes and their support team to understand their sleep environment, duration and timing and can provide a baseline on which these collegiate athletes can improve.

When screening athletes for disordered sleep, it is important to obtain a thorough sleep history. Key issues to address are summarised in box 2 . 61 Current sleep habits describe bedtimes; awakening history; napping; and exposure to light, dark and electronic device use. Sleep quality includes a subjective assessment of ‘average sleep’, feeling rested and presence of daytime fatigue or somnolence. Family medical history should screen for a history of insomnia, narcolepsy, sleep apnoea, depression, anxiety, attention deficit hyperactivity disorder or other psychiatric disorders (eg, somatoform disorders, substance abuse and personality disorders). A sleep diary can be a valuable tool for establishing baseline sleep habits and identifying changes in hygiene practices.

In general, subjective screening questionnaires 44–58 and objective clinical-grade measurements 44 45 57 59 60 focus on the diagnosis and treatment of sleep disorders such as sleep-disordered breathing (eg, obstructive sleep apnoea), insomnia, narcolepsy and circadian rhythm sleep disorders. The presence of these and other sleep disorders may be tested in collegiate athletes during their preparticipation physical exam or in those seeking diagnosis and treatment for sleep problems. Sports medicine team members can also use subjective measures (see online supplementary table 5 ) to refer collegiate athletes to team physicians, licenced mental health providers and board-certified sleep medicine professionals. These specialists can diagnose sleep disorders using clinical-grade objective measurements and implement treatment plans.

Sleep measurement can be either subjective, assessed mostly through questionnaires, or objective, occurring in either a sleep laboratory or at home (see online supplementary table 5 ). Objective testing can be further subdivided into ‘clinical grade’ measurements that are Food and Drug Administration (FDA) approved to assess and diagnose sleep disorders, or ‘consumer-based’, 42 43 which lack FDA approval but can measure sleep continuously in the subject’s typical sleeping environment. The clinical sleep laboratory environment, where detailed objective testing such as polysomnography 44 and multiple sleep latency testing 45 occur, has the advantage of accuracy and detail, and the disadvantage of an atypical sleeping environment, which can influence the sleep it intends to measure. Furthermore, this testing only occurs during a discrete period of time. Objective sleep assessment can also occur in the home environment, which has the advantage of familiarity and longitudinal measurement but has the disadvantage of limiting the number of possible measures and compromised accuracy compared with sleep laboratory measures.

Interventions to improve sleep

Evidence-based approaches to improving sleep include behavioural, social and pharmacological interventions. Here we review how they apply to collegiate athletes, noting that in many instances the evidence base is primarily among college students more generally. Nearly three-quarters of college students report receiving no health education from their universities about how to manage sleep difficulties.12 Interventions are particularly important for collegiate athletes who struggle to practice good sleep hygiene due to heightened time demands and for whom poor sleep impairs both academic and athletic performance. Unique elements of the collegiate athlete experience may present important opportunities for population-specific tailoring of educational messaging. For example, less than one-quarter of NCAA Division I collegiate athletes at a single institution regarded sleep as a way to recover from a game.62 Knowledge translation about sleep’s positive impact on athletic performance is an important starting point for population-tailored educational interventions.

The most common non-pharmacological sleep interventions studied in college-aged populations63–65 include cognitive–behavioural therapy for insomnia (CBT-I), sleep hygiene and education and relaxation/mindfulness. In general, CBT-I has shown large effect sizes across numerous studies.64 While CBT-I is generally focused on insomnia complaints, sleep hygiene and education interventions have been disseminated widely to college students. These interventions have generally resulted in small to moderate improvements in sleep quality64 and sleep knowledge.63 In addition, when used as stand-alone interventions, relaxation and mindfulness generally lead to moderate sleep improvements.64 66 Overall, sleep interventions in college students are associated with a full range of effect sizes, with increases in sleep duration and sleep efficiency and decreases in sleep onset latency and wake after sleep onset.64

Among collegiate athletes in particular evidence is more limited. Two studies prescribed increased sleep duration to small samples of basketball players19 and tennis players.20 One week20 or 5–7 weeks19 of sleep extension (ie, increasing daily sleep duration to >9–10 hours) were associated with significant increases in sleep duration, decreases in sleepiness and improvements in sport-specific performance indices (eg, tennis serve accuracy and sprint times, basketball shooting accuracy and faster reaction times). However, these studies did not include long-term follow-up, so the persistence of improvements is unknown. Two other studies reported on interventions focused on sleep hygiene and health for collegiate athletes. A 1-month sleep health intervention (delivered via pamphlet) improved self-reported sleep and improved perceived soccer performance among soccer players.67 In addition, preliminary analyses of a pilot 10-week sleep health intervention indicated significantly better sleep, energy levels and collegiate athlete mental health.68 Several studies have examined the effects of sleep interventions in trained athletes, primarily young adults.69 Short-term (ranging from a single night to 1 week) sleep hygiene interventions have modestly improved sleep duration but not other sleep parameters or markers of athletic performance.70–72 Improvement in perceived recovery was found in one study71 but not another.70 Biofeedback did not improve sleep quality in a sample of soccer and track athletes,73 and progressive muscle relaxation led to minimal improvements in sleep among dancers.74 Short-term (48 hours) or long-term (4 weeks) restrictions on use of late-night electronic devices did not improve sleep75 76 or various markers of athletic and cognitive performance,76 and five nights of sleep extension led to minimal improvements in measures of sleep or performance in adolescent pistol shooters.77 In contrast, interventions involving comprehensive sleep education, feedback and tailored approaches to behaviour change over several weeks significantly improved sleep.78 79 Finally, in a sample of golfers with sleep apnoea, treatment with continuous positive airway pressure therapy significantly improved sleep quality, decreased reported sleepiness and lowered golf handicaps.80

Although some collegiate athletics departments have modified their facilities or added programmes to improve sleep (eg, creation of napping rooms and comprehensive sleep monitoring systems), it remains unclear whether these strategies have improved collegiate athlete sleep. Overall, in addition to minimal research on non-pharmacological sleep interventions among collegiate athletes, the literature is greatly limited due to: small sample sizes, lack of control groups, insufficient sleep measures and minimal consideration for other relevant domains (eg, cognition, mental health, academic performance and sport performance).

Three per cent of NCAA collegiate athletes report non-prescription sleep aid use, while 18.7% of NCAA collegiate athletes report prescription sleep aid use.81 However, there is a dearth of literature on pharmacological treatment of insomnia and other sleep disorders in collegiate athletes; furthermore, hypnotic medication use among college students is broadly discouraged due to cognitive side effects and potential for adverse events when used with other drugs (eg, alcohol).65 For these reasons, pharmacological recommendations as sleep aids were considered beyond the scope of the Interassociation Task Force on Sleep, and the reader is referred to the International Olympic Committee consensus statement on mental health in elite athletes for a detailed discussion of this matter.82 Given the broad concerns of medication aids for sleep in collegiate athletes, insomnia-related complaints in this population should be managed behaviourally, since CBT-I produces similar short-term treatment outcomes and superior long-term treatment outcomes compared with pharmacotherapy.83 Nevertheless, given the seemingly high prevalence of sedative-hypnotic use among collegiate athletes, more research on sleep medication use among collegiate athletes is needed to understand its sleep, health and performance-related implications.84