Running on Empty: Self-Reported Sleep/Wake Behaviour during Ultra-Marathon Events Exceeding 100 Miles

ABSTRACT‘How much sleep does one need?’ is a critical question that has been difficult to answer. The long history of sleep research has culminated in population‐derived normative values of 7 to 9 h of sleep per night to avoid dysfunction. Such a wide range is sufficiently large that one cannot know what is required for any given individual. ‘Sleep need’ cannot currently be directly measured, might not be represented by one number (given the multiple functions that sleep subserves), and likely varies from individual‐to‐individual and from day‐to‐day. This said, the concept should be embraced and can be considered alongside more easily operationalised and routinely measured constructs of ‘sleep opportunity’ (e.g., time in bed) and ‘sleep ability’ (i.e., the obtained sleep, such as sleep duration). Considering the dynamics of all three constructs together may drive greater understanding about sleep health, sleep insufficiency, and sleep disorder pathology. In this article, we describe a new theory called Sleep Opportunity, Need, and Ability and provide a rationale for why this theory has both theoretical and clinical value.

To determine whether variation in sleep duration reflects variation in sleep need or self-imposed sleep restriction. After habitual bedrest duration of participants was assessed during a 2-week outpatient protocol, volunteers were scheduled to sleep according to this schedule for 1 week prior to and the first night after admission to a general clinical research center. The inpatient protocol included multiple sleep latency testing on the second day and sleep recordings during a bedrest extension protocol that included 16 hours of sleep opportunity (12 hours at night and 4 hours at midday) for 3 consecutive days. Outpatient monitoring followed by inpatient assessment of sleep. Seventeen healthy volunteers (10 women) aged 18-32 years without clinical sleep disorders. Extension of sleep opportunity. The habitual bedrest duration varied from 6.1 to 10.3 hours. Individuals with shorter habitual bedrest duration fell asleep more quickly and frequently during the multiple sleep latency test than did those with longer habitual bedrest duration. On the first day of extended sleep opportunity, the total sleep time of all individuals was greater than their habitual bedrest duration; the average increase in total sleep time was 4.9 hours (P = 0.001). The increase in total sleep time declined across the 3 day bedrest-extension protocol (P = 0.003 for trend). During the third day of increased sleep opportunity, the total sleep time was negatively associated with habitual bedrest duration (P = 0.005); individuals with shorter habitual bedrest duration continued to sleep more than those with longer habitual bedrest duration. Those individuals with shorter habitual sleep durations carry a higher sleep debt than do those with longer habitual sleep duration. Interindividual variation in sleep duration may primarily reflect variation in self-selected sleep restriction or wake extension.

To investigate sleep duration and sleep loss during antenatal period and assess associative factors, including maternal characteristic and mood symptoms. A cohort of 3038 women was enrolled. Self-reported sleep duration and sleep loss, the latter being calculated from preferred sleep need and actual sleep duration, were measured in early, mid- and late pregnancy, and at delivery. The associations with age, BMI, parity, education, smoking, napping, and depressive and anxiety symptoms were evaluated. Sleep duration was longest in early pregnancy and shortest at delivery (7.93h-7.76h, p < 0.001). The proportion of short sleepers (< 6h) increased from 1.4% to 5.9% throughout the studied period (p < 0.001). Mean sleep loss remained stable in early- and mid-pregnancy, lowering in late pregnancy (p < 0.001) and increasing again until delivery (p = 0.003). The number of women with notable sleep loss (> 2h) was similar during the first three measurement points (9.4%, 8.9% and 9.5%), but increased until delivery (14.1%, p < 0.001). Older, multiparous, and more-depressive women slept less (p < 0.001, p < 0.001, p = 0.017). Women with higher BMI were more likely to sleep < 6h in late pregnancy (p = 0.012). Multiparous, more-depressive, and higher-BMI women reported more sleep loss (p < 0.001, p < 0.001, p = 0.049). We confirmed earlier reported decrease in sleep duration at the end of pregnancy. As a novel finding, we showed a notable increase in sleep loss during the last month of pregnancy. Various factors were associated with both short sleep and sleep loss, especially multiparity, napping and depressive symptoms.

PurposeTo evaluate chronotype and the sleep management strategy adopted by sailors before the offshore solo sailing race “Mini Transat La Boulangère”. As secondary aim, we assessed whether adopting pre-race sleep management strategy influences performance at race.Materials and MethodsForty-two solo sailors completed questionnaires on sleep quality, sleepiness, chronotype and an ad hoc questionnaire on the pre-race sleep management strategy adopted. Arrival times, separately for each race’s leg, were provided by the race organization team.ResultsSolo sailors present mainly with a morning-type (40%) and intermediate-type (60%) chronotype, while none have an evening-type chronotype. Fifty-five percent of sailors adopted pre-race sleep management strategy. Sailors that adopted strategy have travelled more miles in offshore compared to sailors that did not adopt strategy (p<0.05). Significant differences emerged in rMEQ scores, with sailors that adopted strategy presenting lower score compared to sailors that did not adopt sleep strategy (p<0.05), as well as in chronotype distribution with morning-type sailors that are less likely to adopt pre-race sleep management strategy compared to intermediate type sailors (p<0.05). No differences emerged in final arrival times and in arrival time at leg1 and leg2. The most commonly adopted strategy (52% of sailors) consists of sleep extension, followed by the polyphasic sleep (26%), and sleep deprivation (22%) strategy. Sailors trained in polyphasic sleep have higher ESS than sailors trained in sleep deprivation (p<0.05).ConclusionMorning-type chronotype is overrepresented in this large cohort of solo sailors compared to the general population; moreover, chronotype seems to influence the adoption of sleep management strategy. A little over half of solo sailors participating in the Mini Transat trained in sleep management strategy before the race; however, neither the general adoption of pre-race sleep management strategy nor the adoption of a specific sleep strategy seems to significantly influence final arrival times.

Sleep duration versus sleep insufficiency as predictors of cardiometabolic health outcomes

Épidémiologie des accidents liés aux troubles du sommeil.

Cardiovascular disease is the leading cause of death in the United States. Chronic short sleep duration is also a significant public health problem and has been linked to several markers and outcomes of cardiovascular disease. To date, inconsistency of assessments of sleep duration and insufficiency, use of covariates, and cardiovascular disease measurement across studies limits strong conclusions about the relationship between sleep duration, sleep insufficiency, and cardiovascular disease. The current study examined the association between sleep duration, sleep insufficiency, and a marker of preclinical coronary heart disease (i.e., carotid intima-media thickness) in a community sample using a cross-sectional design. Some evidence for a relationship between sleep duration and cIMT was found, with longer sleep duration predicting higher cIMT in some segments. Additionally, the interaction between sleep duration and sleep insufficiency was significant. However, neither of these effects were significant after adjusting for age and in some cases race/ethnicity, suggesting demographics may explain this association. Actigraphy and sleep diary duration assessments demonstrated significantly different correlations with cIMT in some segments, suggesting the nature of the assessment method may impact the strength or direction of the relationship between sleep duration and cIMT. Limitations and future directions are discussed.

ObjectivesJuvenile idiopathic arthritis (JIA) is a common chronic childhood disease and chronic pain is a debilitating feature. A strong link has been shown between poor sleep and pain in JIA....

Many people are concerned about whether they are getting “enough” sleep, and if they can “sleep too much”. These concerns can be approached scientifically using experiments probing long-term (i.e., multi-night) sleep homeostatic processes, since homeostatic processes move the system towards its physiological setpoint (i.e., between “not enough” and “too much”). We analyzed sleep data from two human studies with sleep opportunities much longer than people usually stay in bed (i.e., conditions in which sleep homeostatic responses could be documented): sleep opportunities were 14-16 hours per day for 3-28 days. Across the nights of the extended sleep opportunities, total sleep duration, Rapid Eye Movement (REM) sleep duration and non-REM sleep durations decreased and sleep latency increased. Multiple nights were required to reach approximately steady-state values. These results suggest a multi-day homeostatic sleep process responding to self-selected insufficient sleep duration prior to the study. Once steady state-values were reached, there were large night-to-night variations in total sleep time and other sleep metrics. Our results therefore answer these concerns about sleep amount and are important for understanding the basic physiology of sleep and for two sleep-related topics: (i) the inter-individual and intra-individual variability are relevant to understanding “normal” sleep patterns and for people with insomnia and (ii) the multiple nights of sleep required for recovery from insufficient sleep from self-selected sleep loss is important for public health and other efforts for reducing the adverse effects of sleep loss on multiple areas of physiology.

Introduction Poor sleep hygiene is common in American college students, with the majority reporting insufficient sleep. Previous studies suggest that many students extend sleep during the weekend to recover sleep debt accrued during the week. In the current study we objectively measured sleep to determine if weekend catch-up sleep was practiced. We also provided students with a 9h sleep opportunity in order to observe how an extended sleep period affected sleep architecture. Methods Students (N=36, 20 women, 19.9±1.7 years) participated in the study from September 2019-March 2020. Sleep-wake behavior was assessed for two weeks using wrist actigraphy and a twice-daily diary. During this two-week period, participants wore at-home polysomnography (PSG) on two non-consecutive nights. For these two nights, in counterbalanced order, participants were instructed to follow their typical sleep pattern or to extend their sleep opportunity to 9h. Within-subjects ANOVA were used to compare sleep between week (Sunday-Thursday) and weekend (Friday and Saturday) nights as well as between typical and 9h PSG nights. Results Compared to week nights, participants went to bed 35 minutes later and woke up 58 minutes later on weekend nights (ps&amp;lt;0.01). Measures of sleep duration and sleep continuity were comparable (ps&amp;gt;0.10) between week and weekend nights and indicated that students averaged less than 7h of sleep per night (6.3±1.0h on week nights and 6.7±1.1h on weekend nights). Self-report measures of sleep quality and daytime sleepiness were also comparable between week and weekend nights (ps&amp;gt;0.05). When instructed to extend their sleep opportunity to 9h, participants exhibited high adherence and increased total sleep time by 88 minutes compared to the typical night (p&amp;lt;0.05). This increase in sleep was due to significant increases in time spent in all four stages of sleep (NREM S1-3 and REM sleep, ps&amp;lt;0.05). Conclusion In this study, students did not utilize weekend nights to extend sleep in order to recover accumulated sleep debt from the week. When provided with a 9h sleep opportunity, participants were physically able to extend sleep and exhibited high quality sleep, suggesting that the primary driver of insufficient sleep in this population is a lack of sleep opportunity rather than impaired sleep ability. Support (If Any)

Associations between sleep duration and sleep debt with insulin sensitivity and insulin secretion in the EGIR-RISC Study

Introduction Short sleep duration is linked to increased psychiatric risks, yet the protective role of subjective sleep sufficiency in short sleepers remains unclear. This study examines how reported sleep duration and subjective sleep sufficiency influence anxiety, depression, and fatigue in a Korean adult population. Methods Data from 2,492 participants in the Korean Sleep Headache Study were analyzed (age range: 19-92, mean 47.9 ± 16.4yrs, 49.6% male). Reported sleep duration was classified as inadequate (&amp;lt; 7 hours) or adequate (≥7 hours) based on weighted weekly averages from the Korean Munich Chronotype Questionnaire. Subjective sleep sufficiency was assessed via the question, “Do you think you are getting enough sleep at night?” with responses categorized as “sufficient” or “insufficient.” Anxiety, depression, and fatigue were defined using Generalized Anxiety Disorder-7 (≥10), Patient Health Questionnaire (≥10), and Fatigue Severity Scale (≥36), respectively. Logistic regression analyses, adjusting for sociodemographic, lifestyle, and sleep quality covariates, were performed to evaluate the associations between reported sleep duration and sufficiency on anxiety, depression, and fatigue. Results Participants reported inadequate sleep in 42.87% and insufficient sleep in 56.11%. Inadequate sleep duration was significantly associated with higher odds of anxiety and fatigue (OR [95% CI], 4.13 [1.75-11.41], p=0.003, and 1.33 [1.12-1.61], p= 0.002, respectively), while insufficient sleep was significantly associated only with fatigue (1.43 [1.18-1.72], p&amp;lt; 0.001). Depression was not significantly associated with either. Participants were categorized into sufficient adequate sleep (26.67%), insufficient adequate sleep (30.46%), sufficient inadequate sleep (17.22%), and insufficient inadequate sleep (25.65%). Notably, insufficient inadequate sleepers had the highest odds of anxiety (3.92 [1.24-17.42], p=0.036) and fatigue (1.89 [1.46-2.45], p&amp;lt; 0.001) compared to sufficient adequate sleepers, followed by insufficient adequate sleepers (1.48 [1.16-1.89], p=0.002) and sufficient inadequate sleepers (1.40 [1.06-1.86], p=0.018) for fatigue. For depression, insufficient inadequate sleepers showed slightly higher odds (1.22 [0.80-1.85], p=0.354), though this was not statistically significant. Conclusion Inadequate sleep duration and insufficient subjective sleep may exacerbate on daytime symptoms such as anxiety and fatigue. While sufficient subjective sleep may mitigate the impact of short sleep, particularly on fatigue, securing adequate sleep remains essential for managing mood and fatigue. Support (if any)

Chronic sleep restriction (CSR) has been associated with adverse effects including cognitive impairment and increased risk of diabetes and cardiovascular disease. Yet, sleep restriction therapy is an essential component of most behavioral treatments for insomnia. Moreover, little is known about the impact of CSR on sleep continuity and structure in healthy people whose need for sleep is satiated. We investigated the impact of CSR on sleep continuity and structure in nine healthy participants. They had 4 nights of sleep extension, 2 nights of post-extension sleep, 21 nights of CSR (5/5.6-hour time-in-bed), and 9 nights of recovery sleep. Compared to postextension sleep, during CSR sleep duration was reduced by 95.4 ± 21.2 min per night, Slow-Wave Activity was significantly increased, and sleep was more consolidated. During recovery, sleep duration was increased by 103.3 ± 23.8 min compared to CSR, and the CSR-induced increase in Slow-Wave Activity persisted, particularly after the 5-hour exposure. Yet, we found that sustained vigilant attention was not fully recovered even after nine nights of recovery sleep. Our results suggest that CSR improves traditional metrics of sleep quality and may have a persistent impact on sleep depth, which is consistent with the reported benefits on sleep continuity and structure of sleep restriction therapy. However, these improvements in traditional metrics of sleep quality were associated with deterioration rather than improvement in neurobehavioral performance, demonstrating that sleep duration should be included in assessments of sleep quality. These results have implications for the long-term use of sleep restriction in the behavioral treatment of insomnia. Clinical Trial Registration: Impact of Chronic Circadian Disruption vs. Chronic Sleep Restriction on Metabolism (https://clinicaltrials.gov/ct2/show/; #NCT02171273).

Objective: Sleep deprivation among teens is a major health issue. Only 15% of teens get 8.5 h of sleep on school nights. Sleep deprivation can lead to poor grades, sleepiness and moodiness. We undertook a study to assess the prevalence of sleep habit disturbance among elementary school students in South Texas with Hispanic ethnicity predominance. We also found how much a video based on sleep education had an impact on these children. Method: Once the Corpus Christi Independent School District (CCISD) approved the collection of baseline sleep data, questionnaires were administered using the Children’s Sleep Habit Questionnaire (CSHQ.) These questionnaires were distributed prior to the viewing of the educational and animated movie KNIGHTS (Keep Nurturing and Inspiring Good Habits in Teen Sleep). Four months later, a random follow-up was performed and the children were requested to respond to the same CSHQ. Results: 264 children from two elementary schools participated in this educational program. At baseline, 55.56% of the children had trouble sleeping. When the questionnaire was administered four months later, only 23.26% (p < 0.05) had trouble sleeping. Additionally, at baseline, approximately 60–70% children had some baseline bedtime resistance, anxiety dealing with sleep, issues with sleep duration and/or awakenings in the middle of the night. In the follow up questionnaire, results showed significant improvements in overall sleep habits, bedtime resistance, sleep anxiety and night awakenings amongst students (p < 0.05). However, no significant differences were seen in sleep duration and daytime sleepiness. Conclusion: Sleep deprivation and good sleep habits remain as a pervasive challenge among elementary school students. Administering an animated video about sleep education along with a provider-based education may be an effective tool for educating elementary school students and decreasing the prevalence of these sleep-related issues. Future prospective randomized studies are suggested.

Whether short or insufficient sleep are risk factors for new-onset nocturnal gastroesophageal reflux (nGER). In this 10-year longitudinal study, adult general-population women in Uppsala, Sweden, answered questionnaires on sleep, nGER, and other conditions on 2 occasions. Participants at baseline totaled 6,790, while participants at follow-up totaled 4,925. "Short sleep" was defined as sleeping < 6 hours/night and "insufficient sleep" was defined as reporting an average actual sleep duration below 80% of the self-estimated need for sleep duration but without "short sleep." nGER was defined as reporting heartburn or acid reflux after going to bed sometimes, often, or very often. The confounding factors-age, body mass index, physical activity, caffeine intake, smoking habits, alcohol dependence, depression, anxiety, and snoring-were defined from the questionnaire. At baseline, 839 participants reported short sleep and 1,079 participants were defined as having insufficient sleep. Both participants with insufficient sleep and short sleep had nGER more often than those with sufficient sleep (26% vs 17% vs 10%, respectively). At follow-up, a new onset of nGER was twice as common among those with insufficient or short sleep at baseline and follow-up, compared with those with sufficient sleep at baseline and follow-up, even after adjusting for confounding factors (odds ratio 2.0 [1.5-2.8], P < .001). Insufficient sleep and short sleep are associated with nGER. Persistent insufficient and/or short sleep independently increases the risk of developing nGER over a 10-year follow-up. Women seeking treatment for nGER should be questioned about their sleep habits to identify insufficient sleep as a possible causative factor. Emilsson OI, Al Yasiry H, Theorell-Haglöw J, Ljunggren M, Lindberg E. Insufficient sleep and new onset of nocturnal gastroesophageal reflux among women: a longitudinal cohort study. J Clin Sleep Med. 2022;18(7):1731-1737.