Disruptions to sleep and circadian rhythms are associated with poorer athlete mental health in female, but not male, elite Australian Rules footballers.

Elite athletes are vulnerable to sleep and circadian disruption and associated mental health symptoms. This study aimed to investigate sex differences in sleep, circadian rhythms, and mental health, as well as the moderating role of sex in the prediction of mental health, among male professional and female semi-professional elite athletes. Participants were 87 elite Australian Rules football (ARF) athletes (43% female; mean [standard deviation] age 24.0 [4.1] years). Participants completed baseline questionnaires, 2 weeks of sleep/wake monitoring via actigraphy, and a circadian phase assessment (dim-light melatonin onset [DLMO]). Cross-sectional data were collected in training-only Australian Football League (AFL) Men's and Women's pre-season periods, with 53 providing data in two pre-seasons. Female athletes, relative to males, reported poorer mental health (a higher athlete psychological strain score), had a later mid-sleep time (by 28 min), reported a greater preference towards eveningness, and displayed a later circadian phase (by 33 min). For female athletes, lower sleep efficiency and lower sleep regularity were associated with poorer mental health. For female athletes, there were U-shaped relationships between both morningness-eveningness and phase angle (interval between sleep onset and DLMO time) and mental health. No significant relationships were found for male athletes. In summary, elite female ARF athletes reported poorer mental health, relative to males, especially when experiencing sleep or circadian disruption. Lifestyle factors associated with sex differences in ARF professionalism (scheduling, finances, supports) may contribute to these findings. Programmes to improve sleep, circadian alignment, and mental health among female semi-professional elite athletes should be strongly considered.

Sleep patterns before and after competition: A real-world examination of elite athletes.

Good sleep before and after competitions is crucial to cognitive, physiological performance and recovery. Yet, elite athletes face a unique set of challenges when acquiring good sleep before and after competitions, and indeed commonly report sleep problems when it matters most. This study examined the sleep of elite athletes before and after competition compared to before and after free days. A total of 1808 unique nights of actigraphy (n = 1495) and sleep diary (n = 1335) data from elite Australian Football League and National Rugby League male athletes (N = 85, M-age = 24.4 ± 3.6) were collected and analysed using multi-level mixed models. On nights before competitions, athletes advanced sleep timings (p < .001, d = 0.63) and increased total sleep time (p < .001, d = 0.65) compared to nights before free days. On nights after competitions, athletes delayed sleep timings (p < .001, d = 1.64), reduced total sleep time (p < .001, d = 1.28), and had significantly worse quality sleep (p < .001, d = 0.71) compared to nights after free days. Sleep was especially worse following night competitions. While elite athletes and organisations may be implementing effective sleep strategies to optimise sleep the night before competitions, strategies to improve sleep after competitions may be lacking. We discuss potential factors contributing to this asymmetry and propose areas for research moving forward.

Home is where the hustle is: the influence of crowds on effort and home advantage in the National Basketball Association.

Studies have consistently shown crowds contribute to home advantage in the National Basketball Association (NBA) by inspiring home team effort, distracting opponents, and influencing referees. Quantifying the effect of crowds is challenging, however, due to potential co-occurring drivers of home advantage (e.g., travel, location familiarity). Our aim was to isolate the crowd effect using a "natural experiment" created by the Coronavirus disease 2019 (COVID-19) pandemic, which eliminated crowds in 53.4% of 2020/2021 NBA regular season games (N = 1080). Using mixed linear models, we show, in games with crowds, home teams won 58.65% of games and, on average, outrebounded and outscored their opponents. This was a significant improvement compared to games without crowds, of which home teams won 50.60% of games and, on average, failed to outrebound or outscore their opponents. Further, the crowd-related increase in rebound differential mediated the relationship between crowds and points differential. Taken together, these results suggest home advantage in the 2020/2021 NBA season was predominately driven by the presence of home crowds and their influence on the effort exerted to rebound the basketball. These findings are of considerable significance to a league where marginal gains can have immense competitive, financial, and historic consequences.

Cognitive fitness modulates gender differences in sleep and mental health among competitive athletes under chronic stress.

Objectives: Mental fitness is increasingly considered a key component of an athlete's competitive arsenal. Active domains of mental fitness include cognitive fitness, sleep, and mental health; and these domains can differ between men and women athletes. Our study investigated the associations of cognitive fitness and gender to sleep and mental health, and the interaction between cognitive fitness and gender on sleep and mental health, in competitive athletes during the COVID-19 pandemic. Methods: 82 athletes competing at levels from regional/state to international (49% women, M-age = 23.3 years) completed measures of self-control, intolerance of uncertainty, and impulsivity (together representing constructs of cognitive fitness), items about sleep (total sleep time, sleep latency, and mid-sleep time on free days) and a measure of mental health (depression, anxiety, and stress). Results: Women athletes reported lower self-control, higher intolerance of uncertainty, and higher positive urgency impulsivity compared with men athletes. Women reported sleeping later, but this gender difference disappeared after controlling for cognitive fitness. Women athletes-after controlling for cognitive fitness-reported higher depression, anxiety, and stress. Across genders, higher self-control was associated with lower depression, and lower intolerance of uncertainty was associated with lower anxiety. Higher sensation seeking was associated with lower depression and stress, and higher premeditation was associated with greater total sleep time and anxiety. Higher perseverance was associated with higher depression for men-but not women-athletes. Conclusion: Women athletes in our sample reported poorer cognitive fitness and mental health compared to men athletes. Most cognitive fitness factors protected competitive athletes under chronic stress, but some exposed them to poorer mental health. Future work should examine the sources of gender differences. Our findings suggest a need to develop tailored interventions aimed at improving athlete wellbeing, with a particular focus on women athletes.

Approaches to the assessment of adherence to CBT-I, predictors of adherence, and the association of adherence to outcomes: A systematic review.

This systematic review (PROSPERO registration CRD42020158010) aimed to: 1) assess how adherence to cognitive behavioural therapy for insomnia (CBT-I) has been measured; 2) evaluate predictors of adherence; and 3) determine whether treatment outcome is associated with adherence. Inclusion criteria included: adults with insomnia; an intervention of CBT-I, including sleep restriction and/or stimulus control; a reported measure of adherence; and written in English. Searches of eight databases returned 2038 publications as of April 2021. The final sample included 102 papers. Publication quality and risk of bias were assessed using Joanna Briggs institute tools. Studies assessed either global adherence or adherence to specific components of CBT-I via questionnaires, sleep diaries, interviews or actigraphy. Twenty-eight papers examined predictors of adherence. Better pre- and post-session sleep, greater psychosocial support, increased self-efficacy, and fewer dysfunctional beliefs about sleep predicted greater adherence. Twenty-eight papers examined whether adherence predicted treatment outcomes. Only insomnia severity index scores post-treatment were consistently predicted by adherence, and only by a few measures of adherence. Overall, there was very little consistency in how adherence was measured, and in predictors and outcome variables assessed. A standardised method for assessing specific adherence constructs is indicated, to fully understand the role of adherence in CBT-I.

Sleep as a Major Determinant for Mental Health Outcomes in Elite Australian Football League (AFL) Athletes.

PURPOSE: The link between mental health and sleep is well documented in the general population, with the majority of mental health disorders involving some type of sleep disturbance. There is, however, limited research investigating this relationship in elite athlete populations. The aim of this study was to identify whether sleep and mental health outcomes are associated in elite athletes and, if so, what measures of sleep were the most predictive of mental health outcomes. METHODS: A comprehensive assessment of sleep was conducted using both objective and subjective methods in 68 Australian Football League athletes (male; mean age, 23.3 ± 3.4 yr; median, 23; range, 18-32 yr). Rest-activity patterns were recorded using wrist actigraphy for an average of 13.8 ± 3.6 d (a total of 884 d of data). Subjective sleep data were collected using daily sleep diaries and validated questionnaires. Validated mental health questionnaires were used to assess depression, anxiety, and stress symptoms. Multiple linear regression modeling was used to investigate the relationship between sleep and mental health. RESULTS: Using a combination of sleep variables, poor sleep predicted 51% of the variation in clinical depression, 42% of the variation in stress, and 31% in clinical anxiety. Self-reported insomnia symptoms (using the Insomnia Severity Index) were the strongest predictors of poor mental health outcomes, followed by objective sleep monitoring via actigraphy. Sleep diary measures were the weakest predictors of mental health. CONCLUSIONS: Our results present poor sleep as a major determinant of impaired mental health outcomes in a population that is constantly under pressure to perform at the highest level and may underreport mental health symptoms. These findings support the inclusion of sleep assessments as an initial screening tool as well as a core component of all routine health and rehabilitation programs.

Eastward Jet Lag is Associated with Impaired Performance and Game Outcome in the National Basketball Association.

Objectives: Elite athletes are often required to travel across time zones for national and international competitions, causing frequent jet lag. The aim of this study was to examine whether the direction of travel-related jet lag is associated with performance in the National Basketball Association (NBA), and if so, to explore potential mechanisms. Methods: Ten seasons comprising of 11,481 games of NBA data from the 2011/2012 to the 2020/2021 regular season were analyzed using multi-level mixed models with one fixed factor (three levels; jet lag direction: eastward vs westward vs no jet lag) and three random factors (team, opponent, game time). Predicted circadian resynchronization rate was accounted for, and home and away games were analysed separately. Mediation analyses were performed to examine potential mechanisms. Results: Among home teams, eastward (but not westward) jet lag was associated with reduced winning (Δ (i.e., change) = -6.03%, p = 0.051, marginal), points differential (Δ = -1.29 points, p = 0.015), rebound differential (Δ = -1.29 rebounds, p < 0.0001), and effective field goal percentage differential (Δ = -1.2%, p < 0.01). As the magnitude of eastward jet lag increased, home team points differential decreased (2 h Δ = -4.53 points, p < 0.05; 1 h Δ = -0.72 points, p = 0.07). No significant associations were found between jet lag and away team performance. Conclusion: Eastward jet lag was associated with impaired performance for home (but not away) teams. Sleep and circadian disruption associated with advancing phase following eastward travel may have significant adverse consequences on performance in the NBA, particularly when recovery time is limited. Sports organisations could consider chronobiology-informed scheduling and interventions to maximise recovery and performance of their athletes.

Nocturnal Wakefulness and Suicide Risk in the Australian Population.

Objective: Temporal patterns for suicide over a 24-hour period have shown mixed results among prior studies. However, analyses of 24-hour temporal patterns for wakeful actions including suicidal behavior should adjust for expected sleep requirements that inherently skew such activities to conventional wakeful times. This study analyzed the time-of-day for suicide cases from the Australian population for the year 2017, adjusting for expected sleep patterns. Identification of time-of-day trends using this methodology may reveal risk factors for suicide and potentially modifiable contributors.Methods: The Australian National Coronial Information System database was accessed, and data for completed suicide were extracted for the most recent completed year (2017). Time of suicide was allocated to one of four 6-hourly time bins across 24 hours, determined from time last seen alive and time found subsequently. Prevalence of suicide for each time bin was adjusted for the likelihood of being awake for each bin according to sleep-wake norms published from a large Australian community survey. Observed prevalence of suicide was compared to expected values predicted from likelihood of being awake across each time bin calculated as a standardized incidence ratio (SIR).Results: For the year 2017, there were 2,808 suicides, of which 1,417 were able to be allocated into one of four 6-hourly time bins. When compared to expected values, suicides were significantly more likely to occur in the overnight bin (2301-0500; SIR = 3.93, P < .001).Conclusions: Higher-than-expected rates of suicide overnight associated with nocturnal wakefulness may represent a modifiable risk factor for triggering suicide events.

Postmigration stress and sleep disturbances mediate the relationship between trauma exposure and posttraumatic stress symptoms among Syrian and Iraqi refugees.

STUDY OBJECTIVES: Sleep disturbance is common in those who experience trauma. In a sample of nontreatment-seeking refugees, we examined the associations between trauma exposure, postmigration stress, sleep symptoms, and posttraumatic psychological symptoms. METHODS: Syrian and Iraqi refugees (n = 86; 51% female; mean age = 45 years) residing in Australia were recruited from the local community. Cross-sectional descriptive design, multinominal regression analyses, and mediation analyses were used. Participants completed measures in Arabic assessing premigration trauma exposure, postmigration stress, sleep symptoms, and mental health. They also completed 7 days of sleep diaries and actigraphy. RESULTS: We identified 34.9% of the participants as normal sleepers, 32.6% as probably having insomnia, and 32.6% as likely having insomnia. Variables associated with greater sleep disturbance (McFadden's R² = 0.57) included greater trauma exposure, increased time of resettlement, greater postmigration stress, and greater presleep arousal. The association of premigration trauma exposure to current posttraumatic symptoms was mediated sequentially by postmigration stress and sleep symptoms. CONCLUSIONS: Our findings highlight the extent of sleep disturbance in refugees. We found evidence for an indirect pathway between trauma exposure and posttraumatic symptoms through premigration stress and sleep (particularly presleep arousal). In the current global refugee crisis, improving the existing system of care in countries experiencing increased migration is critical. Because sleep disturbance is a modifiable condition associated with mental health, targeting sleep could be an important component of psychological interventions for refugees.

Diurnal Rhythm Robustness in Individuals With PTSD and Insomnia and The Association With Sleep.

Posttraumatic stress disorder (PTSD) and insomnia are characterized by sleep disturbances and daytime functional impairments. Actigraphy metrics can quantify diurnal rhythms via interdaily stability, intradaily variability, relative amplitude, and sleep regularity. Here, we (a) compared diurnal rhythms in PTSD, insomnia, and healthy control samples using linear mixed modeling; (b) compared inter-individual variability of diurnal rhythms between groups using variance ratio tests; and (c) examined correlations between diurnal rhythms and sleep measures within the clinical samples. Participants (N = 98) wore wrist-activity monitors for one week and completed the Insomnia Severity Index and Pittsburgh Sleep Quality Index. Both clinical samples displayed significantly lower interdaily stability, relative amplitude, and sleep regularity compared with controls. Individuals with PTSD and insomnia did not differ on mean diurnal rhythm metrics. Both clinical samples showed more inter-individual variability in relative amplitude compared with controls, and the individuals with PTSD were distinguished from those with insomnia by greater inter-individual variability in interdaily stability and relative amplitude. Relative amplitude in the clinical samples was positively correlated with objective sleep efficiency and total sleep time. This is the first study to compare individuals with PTSD and insomnia on measures of diurnal rhythms, revealing those with PTSD and insomnia to have less robust and more variable diurnal rhythms compared with controls. Individuals with PTSD differed from those with insomnia in inter-individual variability of diurnal rest-activity stability and amplitude, highlighting this population as particularly heterogenous. Diurnal rhythm robustness might be considered an intervention target in insomnia and PTSD populations.