Sleep Regularity and Predictors of Sleep Efficiency and Sleep Duration in Elite Team Sport Athletes

Higher Levels of Morning and Daytime Light Exposure Associated with Positive Sleep Indices in Professional Team Sport Athletes

Objective

Light exposure techniques have been recommended to combat sleep issues caused by disruption to circadian regularity in the athletic population, although studies are lacking.

Methods

A total of 17 professional male Australian Football athletes (age ± SD: 22 ± 3 years) wore a wrist actigraph to measure sleep parameters, and a wearable light sensor to measure melanopic equivalent daylight illuminance (mEDI, in lux) for 14 days. Participants completed three sleep questionnaires at the end of the data collection period and completed well-being surveys 6 times. The Sleep Regularity Index (SRI) for each player was also calculated from actigraphy data. Light exposure data were organised into three different timeframes: morning (wake time + 2 hours), daytime (end of morning to 6 pm), and evening (2 hours leading up to bedtime) for analysis. Repeated measures correlation was conducted for objective sleep measures and mEDI values per timeframe. Pearson's correlation was conducted on subjective sleep measures and well-being measures against mEDI values per timeframe.

Results

Higher morning light was associated with significantly (p < 0.001) greater total sleep time (r = 0.31). Higher daytime light exposure was associated with higher subjective sleep quality (r = 0.48, p < 0.05). Higher evening light exposure was associated with higher Athlete Sleep Screening Questionnaire (ASSQ) global scores (r = 0.52, p < 0.05). There were no other significant correlations between light exposure and sleep or well-being measures (p > 0.05).

Conclusion

Higher morning and daylight exposure levels were associated with various positive objective and subjective sleep measures in professional team sport athletes, supporting the need for education on optimising light exposure to improve circadian function, sleep, and health.

Adapting the athlete sleep behavior questionnaire (ASBQ) for Arabic-speaking populations: Translation, reliability testing, and validation using classical theory and item response theory

Sleep is essential for athletes' physical performance as well as their general health, well-being, and quality of life. To assess athletes' sleep behaviors, the Athlete Sleep Behavior Questionnaire (ASBQ) was developed in the English language. However, a validated Arabic-version of the ASBQ is lacking. This study aimed to translate the ASBQ into Arabic (ASBQ-AR) and evaluate its reliability and validity among Arabic-speaking athletes. A total of 458 participants (254 athletes, 202 non-athletes) from four Arabic countries completed the ASBQ-AR and the Insomnia Severity Index (ISI) questionnaires. The psychometric properties of the ASBQ-AR were examined using unidimensional reliability analysis, confirmatory factor analysis (CFA), Item Response Theory (IRT), and convergent validity. The ASBQ-AR had acceptable internal consistency (Cronbach's α = 0.723, McDonald's ω = 0.725) and a factorial structure, confirming its construct validity. CFA demonstrated improved model fit indices after the removal of two potentially misfitting items (items 4 and 13); however, the model's fit to the data remains suboptimal. IRT results indicated that the majority of items demonstrated a good model fit, suggesting effective measurement of the intended construct without significant interference, except for ASBQ-AR 4. Additionally, ASBQ-AR 4 appears to present the highest level of difficulty for respondents. In terms of convergent validity, the mean ASBQ-AR global score was correlated with the mean ISI global score (r = 0.5, p < 0.0001). The ASBQ-AR is a reliable and valid tool for assessing maladaptive sleep practices among Arabic-speaking athletes. Additional refinements to the ASBQ-AR are warranted to optimize its psychometric properties.

Aspects of Elite Female Football Players' Training Loads and Sleep Variations

The current study investigated the associations between female football players' training loads and their sleep variations. The sample included 21 female elite football players from a Norwegian top-league club with a mean age of 24 years (±2.8). Sleep duration, sleep quality, and training load were monitored every day over 273 consecutive days with a Somnofy sleep monitor based on ultra-wideband (IR-UWB) pulse radar and Doppler technology, and a FIFA-approved STATSports APEX 10 Hz GPS tracking system monitoring players' training loads. A multivariate analysis of variance (MANOVA) was conducted to investigate the relationships between the players' training loads and sleep. It was revealed that very high training loads were associated with reduced time in bed (p = 0.005), total sleep time (p = 0.044)), and rapid eye movement (p < 0.001). The present findings show that the female football players' sleep was disrupted when the training load, based on total distance (TDI), was very high. It appears to be a point where their sleep is somewhat consistent through low, medium, and high training loads, but with disrupted sleep when the training load reaches a very high level. Considering the reduced TIB after a very high training load, there should be suggested strategies to improve their sleep, such as extended TIB, to aid in longer TST and improved recovery.

Routine, Routine, Routine: Sleep Regularity and its Association with Sleep Metrics in Professional Rugby Union Athletes

BACKGROUND

Maintaining a consistent sleep and wake time is often reported as a key component of circadian rhythmicity and quality sleep. However, the impact of sleep onset and offset time variability on overall sleep outcomes are underreported in elite athlete populations. This study investigated the relationship between sleep onset and offset time variability using the sleep regularity index (SRI) and measures of sleep and well-being in professional rugby union athletes. Twenty-three professional male rugby union athletes (mean ± SD, age: 23 ± 3 y) underwent sleep monitoring via wrist actigraphy for three weeks during a pre-season phase of training and completed a daily wellness questionnaire. Median SRI was calculated and used to stratify the trainees into two quantile groups: >76.4 SRI (Regular, n = 11) and < 76.4 SRI (Irregular, n = 12).

RESULTS

The regular sleep group showed significantly longer total sleep duration (p = 0.02, d = 0.97) compared to the irregular group (7:42 ± 0:29 vs. 7:18 ± 0:20 h: min per night, respectively). Furthermore, while not statistically significant, the regular sleep group showed greater sleep efficiency and less wake episodes compared to irregular sleepers, as demonstrated by moderate effect sizes (d = 0.71 and 0.69, respectively).

CONCLUSIONS

The results from this study indicate that minimizing variability in sleep onset and offset time is beneficial for increasing sleep duration and may improve sleep efficiency during pre-season training in elite male rugby union athletes. This study provides evidence for the importance of including sleep-wake routines as a key component of sleep education interventions.

Evaluating the reliability of the athlete sleep behavior questionnaire (ASBQ): a meta-analysis of Cronbach's alpha and intraclass correlation coefficient

BACKGROUND

The Athlete Sleep Behavior Questionnaire (ASBQ) was designed to identify maladaptive sleep practices among athletes. The aim of this meta-analysis was to evaluate the internal consistency and the test-retest reliability coefficients of the ASBQ.

METHODS

A systematic search across 10 databases from inception of the ASBQ to August 2023 was performed. Publications that reported estimates of internal consistency and/or test-retest reliability of the ASBQ were included. A random-effects model was employed to estimate the overall reliability measures of the ASBQ.

RESULTS

Meta-analytic results demonstrated a good level of internal consistency within the ASBQ, evidenced by a Cronbach's alpha of 0.73 (95% CI: 0.63 to 0.80). This suggests a modest correlation among the questionnaire items, supporting its reliability as an effective measure of sleep behavior. In terms of test-retest reliability, our meta-analysis revealed a very good degree of consistency (ICC = 0.88; 95% CI: 0.87 to 0.89), suggesting that the ASBQ can serve as an instrument for monitoring and evaluating changes in athletes' sleep behavior over time. No evidence of publication bias was identified.

CONCLUSION

While the ASBQ demonstrates a moderate level of internal consistency, its test-retest reliability suggests that it can serve as an instrument for longitudinal assessments of athletes' sleep behavior. Future studies focusing on refining the ASBQ to optimize its internal consistency and validate its applicability across diverse athletic populations are warranted.

Intraindividual variability in sleep among athletes: A systematic review of definitions, operationalizations, and key correlates

Via systematic review with narrative synthesis of findings, we aimed to document the ways by which researchers have defined, operationalized, and examined sleep variability among athletes. We identified studies in which scholars examined intraperson variability in sleep among athletes via a search of six databases (Web of Science, Embase, Medline, PsycINFO, CINHAL Plus, and ProQuest Dissertations and Theses Global) using a protocol that included keywords for the target outcome (sleep*), population (athlet* OR sport*), and outcome operationalization (variability OR variation OR "standard deviation" OR fluctuate OR fluctuation OR stability OR instability OR reactivity OR IIV OR intraindividual). We complemented this primary search with citation searching of eligible articles. Assessments of study quality captured eight core elements, namely aims/hypotheses, sample size justification, sample representativeness, number of days sleep assessed, measures of sleep and its correlates, missing data, and inferences and conclusions. From a total of 1209 potentially relevant papers, we identified 16 studies as meeting our eligibility criteria. Concept definitions of variability were notably absent from this work and where available were vague. Quantitative deviations from one's typical level of target sleep metrics reflected the essence by which all but one of the research teams operationalized sleep variability. We assessed the overall quality of empirical work as moderate in nature. We propose a working definition of sleep variability that can inform knowledge generation on the temporal, day-to-day dynamics of sleep functioning that is required for personalized interventions for optimizing sleep health.

Sleep in marathon and ultramarathon runners: a brief narrative review

Introduction

Sleep is considered a fundamental biological function in humans necessary for recovery from daily physical activities. Considering the increasing popularity of long-distance running and participation in races such as marathons and ultramarathons, the aim of the present study was to review the relationship of such strenuous physical activities with sleep.

Methods

A search of Scopus was performed on 24/6/2023 using the syntax [ABS (sleep) AND ABS (marathon)] to identify relevant papers, the references of which were hand-searched to find additional sources.

Results

Optimal sleep has been shown to affect injury prevention and susceptibility to infection positively. In turn, participation in a marathon race may influence nocturnal autonomic modulation and disturb homeostasis. Ultramarathon races may have such a long duration that results in sleep deprivation even for several days, where sleep duration is quite below the physiological range. It seems that for ultramarathons of short duration, continuous running and sleep deprivation are beneficial for performance. In contrast, for races longer than 200 miles, it is necessary to develop sleep strategies to sustain performance.

Conclusion

In summary, the longer the distance of a running race, the greater the importance of an optimal sleep for race performance as well as the impact of a race on sleep.

From improved sleep regularity to reduced sleep complaints and mental health conditions: a population-based interventional study using a smartphone-based virtual agent

STUDY OBJECTIVES

To explore the effect of sleep regularity on sleep complaints and mental health conditions (i.e. insomnia, fatigue, anxiety, and depressive symptoms) in a population-based interventional study using a smartphone-based virtual agent.

METHODS

A populational cohort based on the Kanopée application, which provided interactions with a virtual companion to collect data on sleep and make personalized recommendations to improve sleep over 17 days. A pre-intervention sleep diary and interview were used for cross-sectional analysis (n = 2142), and a post-intervention sleep diary and interview were used for longitudinal analysis (n = 732). The intra-individual mean (IIM) and standard deviation (ISD) of total sleep time (TST) were calculated to measure sleep quantity and sleep regularity.

RESULTS

The mean age at baseline was 49 years, 65% were female, 72% reported insomnia, 58% fatigue, 36% anxiety, and 17% depressive symptoms. Before the intervention, irregular and short sleep was associated with a higher likelihood of insomnia (Relative risk [RR] = 1.26 [1.21-1.30] for irregular TST and RR = 1.19 [1.15-1.23] for short TST), fatigue, anxiety, and depressive symptoms. After the intervention, the IIM of the TST increased while the ISD of the TST and sleep complaints and mental health conditions decreased. More regular TST was associated with reduced insomnia and depressive symptoms (RR = 1.33 [1.10-1.52] and RR = 1.55 [1.13-1.98], respectively).

CONCLUSIONS

Our results reveal a longitudinal association between sleep regularity and sleep complaints and mental health conditions. Policymakers, health professionals, and the general population should be aware that, beyond its positive effect on sleep health, regular sleep could promote mental health.

Impact of COVID-19 pandemic on cross-country runners: changes in training, sleep, diet, and mental health

Objective: Determine the impact of the COVID-19 pandemic on the changes in training, sleep, diet, and mental health of cross-country runners. Participants: Cross-country runners from NCAA Division II institutes. Methods: Wilcoxon signed-rank test was performed to analyze survey responses to ordinal questions on the survey while Spearman's rank correlation analysis (ρ) was used to calculate correlation between after the start of pandemic questions. Data was marked significant at p < 0.05. Results: Analysis of the survey responses revealed that cross-country runners were more likely to experience feelings of depression (p < 0.001), lack of motivation (p < 0.001), and higher daily stress (p < 0.001) after the start of the pandemic. After the start of the pandemic, runners running less days per week were more likely to report an increased feeling of depression (ρ=-0.315, p = 0.008) and lack of motivation (ρ=-0.458, p < 0.001). Conclusions: The present study underscores the importance of training, sleep, diet, and mental health amongst cross-country runners.

Sleep and Performance in Professional Athletes

Purpose of Review

Sleep is an essential human behavior that plays a key role in proper biopsychosocial development as well as short- and long-term biological, physical, psychological, and cognitive health. Sleep plays a key role in athletic performance, influencing an athlete's ability to train, recover, and perform, as well as their overall wellness. Over the recent decade, the awareness of sleep's import has penetrated just about every professional sport domain. The purpose of the review was to identify and synthesize the literature published within the past 5 years (2018-2022) that relates to sleep and performance in professional athletes. Literature related to nonprofessional, high-level athletes (e.g., collegiate; Olympic) was omitted as well as those associated with non-traditional professional sports (e.g., eSports).

Recent Findings

Results from 38 articles were incorporated into this review, which covered (1) the sleep's role in the training, physical injury prevention and recovery, competitive performance, and mental health of professional athletes, (2) common sleep problems and disorders in professional athletes, and (3) the impact of unique challenges from training, travel, competition, and other factors on sleep health. Additionally, we provide an orientation to utilized strategies and interventions to assist with sleep health in professional athletes, as well as conclude with a commentary on critical steps forward.

Summary

Sleep plays a critically important role in the training, recovery, performance, and overall wellness of professional athletes. Professional athletes are vulnerable to a variety of sleep-related problems and disorders, due to unique factors related to training, travel, and competition, among other factors. Improved, standardized research methodology and partnerships between professional athletes, coaches, teams, and organizations and researchers are necessary to advance the knowledge of sleep and performance in professional athletes, including identifying sport-specific differences and variation across individual characteristics, as well as developing individualizable, dynamic, and appropriate interventions for improving sleep health among professional athletes.