Sleep, sport, and the brain

Current Aspects of Selected Factors to Modulate Brain Health and Sports Performance in Athletes

This review offers a comprehensive evaluation of current aspects related to nutritional strategies, brain modulation, and muscle recovery, focusing on their applications and the underlying mechanisms of physiological adaptation for promoting a healthy brain, not only in athletes but also for recreationally active and inactive individuals. We propose that applying the rule, among others, of good sleep, regular exercise, and a properly balanced diet, defined as "SPARKS", will have a beneficial effect on the function and regeneration processes of the gut-brain-muscle axis. However, adopting the formula, among others, of poor sleep, stress, overtraining, and dysbiosis, defined as "SMOULDER", will have a detrimental impact on the function of this axis and consequently on human health as well as on athletes. Understanding these dynamics is crucial for optimizing brain health and cognitive function. This review highlights the significance of these factors for overall well-being, suggesting that adopting the "SPARKS" approach may benefit not only athletes but also older adults and individuals with health conditions.

Dietary Strategies to Improve Exercise Performance by Modulating the Gut Microbiota

Numerous research studies have shown that moderate physical exercise exerts positive effects on gastrointestinal tract health and increases the variety and relative number of beneficial microorganisms in the intestinal microbiota. Increasingly, studies have shown that the gut microbiota is critical for energy metabolism, immunological response, oxidative stress, skeletal muscle metabolism, and the regulation of the neuroendocrine system, which are significant for the physiological function of exercise. Dietary modulation targeting the gut microbiota is an effective prescription for improving exercise performance and alleviating exercise fatigue. This article discusses the connection between exercise and the makeup of the gut microbiota, as well as the detrimental effects of excessive exercise on gut health. Herein, we elaborate on the possible mechanism of the gut microbiota in improving exercise performance, which involves enhancing skeletal muscle function, reducing oxidative stress, and regulating the neuroendocrine system. The effects of dietary nutrition strategies and probiotic supplementation on exercise from the perspective of the gut microbiota are also discussed in this paper. A deeper understanding of the potential mechanism by which the gut microbiota exerts positive effects on exercise and dietary nutrition recommendations targeting the gut microbiota is significant for improving exercise performance. However, further investigation is required to fully comprehend the intricate mechanisms at work.

Association between sleep dysfunction and Patient-Reported Outcomes Measurement Information System scores in patients with rotator cuff tears

OBJECTIVES

The purpose of this study was to utilize Patient-Reported Outcomes Measurement Information System (PROMIS) sleep scores to determine the prevalence of sleep dysfunction and its association with other PROMIS scores in patients with rotator cuff tears (RCT).

METHODS

Patients were retrospectively identified using the International Classification of Diseases-10 codes for RCT pathology, and PROMIS outcomes were assessed at multiple visits between November 2017 and February 2020. Generalized linear mixed effects models were fitted with PROMIS sleep score as the predictor variable and other PROMIS scores as the response variable. Additionally, models were fit using a clinically significant dichotomization of PROMIS sleep scores to assess differences in average PROMIS scores.

RESULTS

The study cohort included 481 patients, 201 (41.8 ​%) of whom had disrupted sleep at first visit. A higher percentage of those with disrupted sleep at first visit were female, nonwhite, and not married compared to those with normal sleep. PROMIS scores at first visit differed by sleep category. Higher PROMIS sleep scores were associated with higher anxiety, depression, fatigue, pain intensity, and pain interference scores and lower physical function, social participation, and upper extremity scores. Relationships were similar when dichotomous PROMIS sleep scores were considered.

CONCLUSION

There was a high prevalence of sleep dysfunction in patients with RCT. Sleep disturbance is associated with increased anxiety, depression, fatigue, pain intensity, pain interference and decreased physical function, social participation, and upper extremity function in patients with RCTs.

LEVEL OF EVIDENCE III

Retrospective Cohort Study.

Sleep quality and comfort in fully automated vehicles: A comparison of two seat configurations

As autonomous driving technology advances, the possibility of using vehicles as sleeping environments becomes increasingly relevant. To investigate the feasibility of this concept, a sleep study was conducted with twelve participants who were given a 4-h opportunity window to sleep in both reclined and flat seat configurations. The evaluation involved both objective measures, including polysomnographic (PSG) data analysis, and subjective measures through questionnaires, assessing sleep quality and comfort. While the sleep quantity results were comparable between the two sleeping positions, the reclined position showed a slight advantage in sleep quantity (TST and WASO). Interestingly, a trend highlighting a possible difference was found between the seat positions regarding non-rapid eye movement stage 3 (NREM 3). NREM 3 tended to be in a higher proportion of total sleep time in the flat seat position. Sleep onset latency (SOL) also showed a trend of a shorter latency by participants in the flat position. Additionally, most participants reported a preference for the flat position over the reclined position. These findings suggest that a flat seat configuration could offer a more comfortable and restful sleep environment for passengers in autonomous vehicles.

Sleep, Nutrition, and Injury Risk in Adolescent Athletes: A Narrative Review

This narrative review explores the impact of sleep and nutrition on injury risk in adolescent athletes. Sleep is viewed as essential to the recuperation process and is distinguished as an active participant in recovery through its involvement in growth, repair, regeneration, and immunity. Furthermore, the literature has shown that the sleep of athletes impacts elements of athletic performance including both physical and cognitive performance, recovery, injury risk, and mental well-being. For sleep to have a restorative effect on the body, it must meet an individual's sleep needs whilst also lasting for an adequate duration and being of adequate quality, which is age-dependent. The literature has suggested that athletes have increased sleep needs compared to those of the general population and thus the standard recommendations may not be sufficient for athletic populations. Therefore, a more individualised approach accounting for overall sleep health may be more appropriate for addressing sleep needs in individuals including athletes. The literature has demonstrated that adolescent athletes achieve, on average, ~6.3 h of sleep, demonstrating a discrepancy between sleep recommendations (8-10 h) and actual sleep achieved. Sleep-wake cycles undergo development during adolescence whereby adaptation occurs in sleep regulation during this phase. These adaptations increase sleep pressure tolerance and are driven by the maturation of physiological, psychological, and cognitive functioning along with delays in circadian rhythmicity, thus creating an environment for inadequate sleep during adolescence. As such, the adolescent period is a phase of rapid growth and maturation that presents multiple challenges to both sleep and nutrition; consequently, this places a significant burden on an adolescent athletes' ability to recover, thus increasing the likelihood of injury. Therefore, this article aims to provide a comprehensive review of the available literature on the importance of sleep and nutrition interactions in injury risk in adolescent athletes. Furthermore, it provides foundations for informing further investigations exploring the relation of sleep and nutrition interactions to recovery during adolescence.

The Impact of Multisession Sleep-Hygiene Strategies on Sleep Parameters in Elite Swimmers

PURPOSE

Short sleep duration and poor sleep quality are common in swimmers. Sleep-hygiene strategies demonstrated beneficial effects on several sleep parameters. The present study assessed the impact of a multisession sleep-hygiene training course on sleep in elite swimmers.

METHODS

Twenty-eight elite swimmers (17 [2] y) participated. The sleep-hygiene strategy consisted of 3 interventions. Sleep was measured by actigraphy for 7 days before the beginning of the intervention (baseline), after the first collective intervention (postintervention), after the second collective intervention (postintervention 2), and, finally, after the individual intervention (postintervention 3). The Epworth Sleepiness Scale (ESS) was completed concurrently. Swimmers were classified into 2 groups: nonsomnolent (baseline ESS score ≤ 10, n = 13) and somnolent (baseline ESS score ≥ 11, n = 15).

RESULTS

All swimmers had a total sleep time of <8 hours per night. Sixty percent of swimmers were moderately morning type. Later bedtime, less time in bed, and total sleep time were observed in the somnolent group compared with the nonsomnolent group at baseline. An interaction between training course and group factors was observed for bedtime, with a significant advance in bedtime between baseline, postintervention 2, and postintervention 3 for the somnolent group.

CONCLUSIONS

The present study confirms the importance of implementing sleep-hygiene strategies, particularly in athletes with an ESS score ≥11. A conjunction of individual and collective measures (eg, earlier bedtime, napping, and delaying morning training session) could favor the total sleep time achieved.

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.

Higher training loads affect sleep in endurance runners: Can a high-heat-capacity mattress topper mitigate negative effects?

This study investigates the impact of a training program on sleep among endurance runners and the benefits of chronically using a high-heat-capacity mattress topper (HMT). Twenty-one trained male athletes performed a 2-week usual training regimen, sleeping on a Low-heat-capacity Mattress Topper (LMT), followed by 2-week overload and taper periods. From overload, participants were assigned into two groups based on the mattress topper used: HMT (n = 11) or LMT (n = 10). Irrespective of the group, overload increased general stress and stress-reaction symptoms evaluated by questionnaires, with no decline in performance on a graded-exercise treadmill test, the majority of participant being "non-overreached" (n = 14). From a daily perspective, each additional 100 A.U. in training load, assessed using the session rating of perceived exertion, was associated with an impairment in subsequent sleep efficiency (β = -0.2%; p < 0.01), wake after sleep onset (β =  +0.4 min; p < 0.05) and sleep onset latency (β =  +0.5 min; p < 0.05), which was unaffected by HMT use. Practitioners should be aware of sleep needs, especially during excessive training loads, whereas implementing individualised sleep strategies. Further studies should be conducted on potential benefits of HMT among athletes in various sleep conditions.

Sleep and Sport Performance

SUMMARY

Elite athletes and coaches believe sleep is the most important recovery strategy and widely consider it critical to optimal performance. Despite this perceived importance, there are numerous circumstances that can reduce sleep quantity and quality in athletic populations. Because of the effects of sleep loss on various physical, neurophysiological, and cognitive parameters, such perturbations can have consequences for performance and recovery outcomes. Although peer-reviewed literature examining the interaction between sleep, performance, and recovery in athletes is increasing, understanding of these issues remains equivocal. Perhaps most pertinently, the effect of sleep on sport performance does not align with a one-size-fits-all approach and rather depends on numerous factors such as type of sport, scheduling, time of the season, and the intraindividual requirements for sleep. The relationship between brain plasticity and memory, which in turn can influence learning processes and long-term memory consolidation, suggests that sleep may play an important role in learning new skills and tactics for both elite and developing athletes. The aim of this special issue review was to analyze the evidence of sleep loss on sport performance and recovery, with a specific focus on elite athletes. An assessment of these sleep-compromising situations that elite athletes may face during a typical season and practical considerations for alleviating these issues is also provided to further the understanding for medical professionals, scientists, and applied sporting practitioners alike.

Caffeine and sport

Caffeine is a trimethylxanthine found in coffee and several other foods and beverages. Its stimulatory effects make it an interesting strategy to boost performance for athletic populations. Scientific evidence supports its efficacy to improve high-intensity endurance exercise, explosive and high-intensity efforts, resistance exercise, team sports and combat sports, though individual variation in the ergogenic response to caffeine exists. Supplementation can be taken in many forms including dissolved in water, via capsules, coffee, energy drinks and caffeinated gum; ingestion via capsules, dissolved in water or in caffeinated gum appear to be most effective. Variability in the exercise response following caffeine supplementation may be explained by genetic factors or habitual caffeine consumption. Caffeine is an excellent supplement for athletes looking to improve their exercise performance, though some consideration of side-effects and impact on sleep are warranted.

Pyjamas, Polysomnography and Professional Athletes: The Role of Sleep Tracking Technology in Sport

Technological advances in sleep monitoring have seen an explosion of devices used to gather important sleep metrics. These devices range from instrumented 'smart pyjamas' through to at-home polysomnography devices. Alongside these developments in sleep technologies, there have been concomitant increases in sleep monitoring in athletic populations, both in the research and in practical settings. The increase in sleep monitoring in sport is likely due to the increased knowledge of the importance of sleep in the recovery process and performance of an athlete, as well as the well-reported challenges that athletes can face with their sleep. This narrative review will discuss: (1) the importance of sleep to athletes; (2) the various wearable tools and technologies being used to monitor sleep in the sport setting; (3) the role that sleep tracking devices may play in gathering information about sleep; (4) the reliability and validity of sleep tracking devices; (5) the limitations and cautions associated with sleep trackers; and, (6) the use of sleep trackers to guide behaviour change in athletes. We also provide some practical recommendations for practitioners working with athletes to ensure that the selection of such devices and technology will meet the goals and requirements of the athlete.

Primum non nocere; It's time to consider altitude training as the medical intervention it actually is!

Sleep is one of the most important aspects of recovery, and is known to be severely affected by hypoxia. The present position paper focuses on sleep as a strong moderator of the altitude training-response. Indeed, the response to altitude training is highly variable, it is not a fixed and classifiable trait, rather it is a state that is determined by multiple factors (e.g., iron status, altitude dose, pre-intervention hemoglobin mass, training load, and recovery). We present an overview of evidence showing that sleep, and more specifically the prolonged negative impact of altitude on the nocturnal breathing pattern, affecting mainly deep sleep and thus the core of physiological recovery during sleep, could play an important role in intra- and interindividual variability in the altitude training-associated responses in professional and recreational athletes. We conclude our paper with a set of suggested recommendations to customize the application of altitude training to the specific needs and vulnerabilities of each athlete (i.e., primum non nocere). Several factors have been identified (e.g., sex, polymorphisms in the TASK2/KCNK5, NOTCH4 and CAT genes and pre-term birth) to predict individual vulnerabilities to hypoxia-related sleep-disordered breathing. Currently, polysomnography should be the first choice to evaluate an individual's predisposition to a decrease in deep sleep related to hypoxia. Further interventions, both pharmacological and non-pharmacological, might alleviate the effects of nocturnal hypoxia in those athletes that show most vulnerable.

Schlafqualität und kardialer autonomer Tonus bei Leistungssporttreibenden und in einer Referenzgruppe Gesunder

Leistungssportlerinnen und Leistungssportler sind hohen physischen und psychischen Anforderungen ausgesetzt, um optimale Ergebnisse zu erzielen. Dafür ist auch die Funktion der Regenerationsphase wichtig, zu der maßgeblich ein erholsamer Schlaf beiträgt. Es gibt jedoch Hinweise, dass bei Leistungssportlerinnen und Leistungssportlern aufgrund verschiedener Belastungen im Rahmen des Trainings und der Wettkämpfe gehäuft eine Insomniesymptomatik auftreten kann. Zur objektiven Untersuchung der Schlafstruktur, Schlafqualität und Funktion des kardialen autonomen Tonus wurden Leistungssporttreibende (LS) und eine Gruppe ebenfalls gesunder Kontrollen (GK) mit einer vereinfachten ambulanten Schlafmessung untersucht.

Es wurde in der Gruppe LS bei n = 12 Probanden (Alter 25,1 ± 4,3 Jahre) und in der Gruppe GK bei n = 17 Probanden (Alter 26,1 ± 3,2 Jahre) jeweils weiblichen und männlichen Geschlechts erfolgreich im häuslichen Umfeld eine vereinfachte Schlafmessung einschließlich 1‑Kanal-EKG (SOMNOtouch™) durchgeführt. Mittels Fragebögen wurden die Tagesschläfrigkeit (Epworth Sleepiness Scale, ESS), Insomnieschwere (Insomnia Severity Index, ISI) und Symptome für Schlafapnoe (Aktualisierter STOP-Bang-Fragebogen, aSBF) erhoben. Es wurden visuell die Schlafstadien gescort und aus dem EKG mittels Zeitreihenanalyse Parameter der Herzfrequenz und Herzfrequenzvariabilität (HRV) ausgewertet.

Es traten keine Unterschiede zwischen den Gruppen LS und GK hinsichtlich der ESS und aSBF auf, jedoch war die ISI in der Gruppe LS gegenüber GK erhöht (5,7 ± 4,1 vs. 2,4 ± 2,0; p < 0,02). In Auswertung der Schlafstruktur gab es keine Unterschiede für die Einschlaflatenz (ESL), Gesamtschlafzeit (TST), Schlafeffizienz (SE) sowie für die prozentualen Anteile von Leicht- (N1 + N2), Tief- (N3) und REM-Schlaf (REM), jedoch war die Bettzeit (TIB) in der Gruppe LS erhöht (503,2 ± 52,7 vs. 445,5 ± 45,4 min; p < 0,02). In der Gruppe LS waren gegenüber der Gruppe GK die mittlere nächtliche Herzfrequenz verringert (48,5 ± 6,8 vs. 56,1 ± 5,4; p < 0,01) sowie die HRV-Parameter HRV-Standardabweichung (HRV-SD) (166,0 ± 33,2 vs. 138,2 ± 38,7; p < 0,04), HRV-SD1 (78,8 ± 11,7 vs. 63,2 ± 36,5; p < 0,01) und HRV-SD2 (220,6 ± 48,0 vs. 183,8 ± 45,8; p < 0,05) erhöht.

In der von uns untersuchte Gruppe von Leistungssportlerinnen und Leistungssportlern gibt es Anhaltspunkte für eine leichte Insomnie, wobei die objektiv gemessene Schlafstruktur sich nicht von der gesunder Kontrollen unterscheidet. Dabei ist die TST, mit einem Mittelwert von 6,8 h sowohl in der Gruppe LS als auch in GK, geringer als die von den Fachgesellschaften American Academy of Sleep Medicine (AASM), Sleep Research Society (SRS) und National Sleep Foundation (NSF) empfohlene Schlafdauer für junge Erwachsene. Dagegen war die kardiale autonome Regulation im Schlaf in der Gruppe LS signifikant besser als in der Gruppe GK und ist in Übereinstimmung mit Befunden aus 24-Stunden-Holter-EKG-Studien. Die Entwicklung objektiver, mobiler und belastungsarmer Messverfahren vereinfacht die Erfassung der Schlafstruktur und charakteristischer vegetativer Parameter und könnte zunehmend im personalisierten Gesundheits- und Leistungsmanagement bei Leistungssporttreibenden eingesetzt werden.

Agreement of Sleep Measures-A Comparison between a Sleep Diary and Three Consumer Wearable Devices

Nowadays, self-tracking and optimization are widely spread. As sleep is essential for well-being, health, and peak performance, the number of available consumer technologies to assess individual sleep behavior is increasing rapidly. However, little is known about the consumer wearables' usability and reliability for sleep tracking. Therefore, the aim of the present study was to compare the sleep measures of wearable devices with a standardized sleep diary in young healthy adults in free-living conditions. We tracked night sleep from 30 participants (19 females, 11 males; 24.3 ± 4.2 years old). Each wore three wearables and simultaneously assessed individual sleep patterns for four consecutive nights. Wearables and diaries correlated substantially regarding time in bed (Range CCC_Lin: 0.74-0.84) and total sleep time (Range CCC_Lin: 0.76-0.85). There was no sufficient agreement regarding the measures of sleep efficiency (Range CCC_Lin: 0.05-0.34) and sleep interruptions (Range CCC_Lin: -0.02-0.10). Finally, these results show wearables to be an easy-to-handle, time- and cost-efficient alternative to tracking sleep in healthy populations. Future research should develop and empirically test the usability of such consumer sleep technologies.

Relationship between sleep quality, mood state, and performance of elite air-rifle shooters

Background

To evaluate the impact of pre-competition sleep quality on the mood and performance of elite air-rifle shooters.

Methods

Elite shooters who participated in an air-rifle shooting-competition from April 2019 to October 2019 were evaluated using actigraphy, including Total Sleep Time (TST), Sleep Efficiency (SE), Sleep Latency (SL), Wake-time after Sleep Onset (WASO). Sleep quality was assessed by Pittsburgh sleep quality index (PSQI) and Profile of Mood State (POMS). Mood state was assessed by Competitive State Anxiety Inventory-2.

Results

Study included 23 shooters, of them 13 male and 10 female with the mean age 23.11 ± 4.82 years. The average time to fall asleep was 20.6 ± 14.9 min, TST was 7.0 ± 0.8 h and SE was 85.9 ± 5.3%. Average sleep quality was 5.2 ± 2.2 and tended to decrease as the competition progressed. Pre-competition sleep time in female athletes was significantly higher compared to the competition day (P = 0.05). Pre-competition SL was significantly longer in women than in men (P = 0.021). During training and pre-competition, the tension, fatigue, depression, and emotional disturbance were significantly lower in athletes with good sleep quality. Athletes with good sleep quality had significantly more energy. The PSQI total score positively correlated with cognitive anxiety (r = 0.471, P < 0.01), and somatic anxiety (r = 0.585, P < 0.01), and negatively correlated with energy (− 0.504, P < 0.01) and self-confidence scores (r = − 0.523, P < 0.01).

Conclusion

Poor sleep quality negatively impacted the mood of athletes; however, sleep indices and competition performance of athletes during competitions were not significantly correlated.

Clinician Impact on Athlete Recovery and Readiness in a 24-Hour Training Cycle

This paper explores a 24-hr training cycle and how clinicians contribute to an athlete’s transition from recovery to readiness. The cycle is divided into three phases: immediate, intermediate, and extended. Phase break down is meant to provide wellness prioritization for the athlete and how the clinician can facilitate sustainable performance during a competitive season.

High sleep quality can increase the performance of CrossFit® athletes in highly technical- and cognitive-demanding categories

BACKGROUND

In current sports science, the important role of sleep quality for health and peak performance is well acknowledged. More precisely, it is evident that the negative combination of stressful factors, low resources, and bad sleep habits causes short-term performance losses as well as long-term health consequences. As the maximization of human performance consisting of multiple fixed workloads is the main motivation in CrossFit® (CF), the aim of the present study was to investigate the influence of high sleep quality on performance in CrossFit® athletes (CFA) and the different training categories that are addressed in CF.

METHODS

In total, 149 CFA (81 females, 68 males; 32.01 ± 7.49 years old, 2.56 ± 1.77 active years in CF) filled in the online survey comprising the Pittsburgh Sleep Quality Index (PSQI) and CF performance-specific questions.

RESULTS

It was found that CFA with high sleep quality reported higher values in all performance-related outcomes. Especially in Hero-/Girl-Workouts (χ2 = (1, n = 83) = 9.92, p = .002, φ = 0.37) and Gymnastics (χ2 = (1, n = 129) = 8.74, p = .003, φ = 0.28), performance differed significantly between good and poor sleeping CFA. Since those CF categories are highly technical- and cognitive-demanding high sleep quality seems to play a fundamental role in complex motor skill learning and performance development.

CONCLUSIONS

These results reveal for the first time the positive effects of high sleep quality for performance in CFA and could be used as basis for future studies. Future research should also develop and empirically test suitable interventions to foster high sleep quality in CFA.

TRIAL REGISTRATION

The study was conducted according to the guidelines of the Declaration of Helsinki, and approved by the Ethics Committee of University of the Federal Armed Forces Munich, Germany (06/04/2018).

Long sleep duration is associated with cognitive frailty among older community-dwelling adults: results from West China Health and Aging Trend study

OBJECTIVE

To investigate the association between sleep duration and cognitive frailty among older adults dwelling in western China.

METHODS

We used the baseline data from West China Health and Aging Trend (WCHAT) study. Sleep duration was classified as short sleep duration (< 6 h), normal sleep duration (6-8 h) and long sleep duration (≥ 9 h). Fried frailty criteria and Short Portable Mental Status Questionnaire were used to measure cognitive frailty. Multinomial logistic regression was conducted to estimate odds ratio (OR) and 95% confidence interval (CI).

RESULTS

A total of 4093 older adults (age = 67.8 ± 5.9 years, 1708 males and 2385 females) were included in the analysis. The prevalence of cognitive frailty was 11.8% among older adults in western China. Approximately 11.9% participants had short sleep duration (< 6 h); 22.2% had a long sleep duration (≥ 9 h). After adjusting for covariates, only long sleep duration was significantly associated with high risk of cognitive frailty (OR = 2.07, 95%CI = 1.60-2.68, P <  0.001) in western China older adults compared to normal sleep duration.

CONCLUSIONS

Long sleep duration was significantly related to cognitive frailty in older adults. Intervention for long sleep duration may be helpful to prevent cognitive frailty.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR1800018895 .

Brain-Derived Neurotrophic Factor and Psychophysiological Response in Youth Badminton Athletes During the Season

PURPOSE

To analyze peripheral brain-derived neurotrophic factor (BDNF) levels and psychophysiological parameters in youth badminton athletes during the season and to determine the relationship between variables.

METHODS

Fourteen young badminton athletes were assessed over the season (preseason, middle season, and final season). Serum BDNF (sBDNF) was determined during the preseason and final season. Sleep time, total physical activity, and time in vigorous activity were measured using an accelerometer. The fat-free mass, skeletal muscle mass, fat mass, handgrip strength, cardiorespiratory fitness (VO2max), and dietary intake were evaluated during the season. The Stroop Color and Word Test was employed to assess cognitive tasks. To evaluate the mood, the Brunel Mood Scale was used.

RESULTS

There  were lower sBDNF levels (-16.3% [46.8%]; P = .007) and sleep time (final season = 5.7 [1.1] vs preseason = 6.6 [1.1] h·night-1, P = .043) during the end of the season. The total calories and carbohydrate intake decreased across the season (P < .05). Conversely, better cognitive function was found in the final season with respect to the preseason (P < .05). There were significant correlations between BDNF and VO2max only in the preseason (r = .61, P = .027), but no significant relationship was found among sBDNF and cognitive performance, sleep time, and percentage of won games.

CONCLUSIONS

Youth badminton athletes decreased their sBDNF levels, sleep time, carbohydrate, and calorie intake across the season. The athletes improved in cognitive function; however, only the females improved in body composition, and the males improved their VO2max in the middle season. The sBDNF levels were positively correlated with the VO2max in the preseason, and no correlations were observed among the sBDNF and psychological parameters, sleep time, and sport performance during the season.

The effect of mental fatigue on half-marathon performance: a pragmatic trial

Purpose

It is well established that mental fatigue impairs performance during lab-based endurance tests lasting less than 45 min. However, the effects of mental fatigue on longer duration endurance events and in field settings are unknown. The aim of this study was to investigate the effect of mental fatigue on performance during a half-marathon race.

Methods

Forty-six male amateur runners (means ± SD: age 43.8 ± 8.6 years, $$\dot V{O_{2peak}}$$ V ˙ O 2 p e a k 46.0 ± 4.1 ml/kg/min) completed a half-marathon after being randomly allocated to performing a 50-min mentally fatiguing task (mental fatigue group) or reading magazines for 50 min (control group). Running speed, heart rate, and perceived effort were measured during the race.

Results

Runners in the mental fatigue group completed the half-marathon approximately 4 min slower (106.2 ± 12.4 min) than those in the control group (102.4 ± 10.2 min), but this difference was not statistically significant (Cohen’s d = 0.333; p = 0.265). However, equivalence was not established [t(40.88) = 0.239, p = 0.594] and equivalence testing analysis excluded a beneficial effect of mental fatigue on half-marathon performance.

Conclusion

Due to its posttest-only design and the achievable sample size, the study did not have enough power to provide evidence that the observed 4-min increase in half-marathon time is statistically significant. However, equivalence testing suggests that mental fatigue has no beneficial effect on half-marathon performance in male amateur runners, and a harmful effect cannot be excluded. Overall, it seems prudent for endurance athletes to avoid mentally fatiguing tasks before competitions.

Effect of the Depth of Cold Water Immersion on Sleep Architecture and Recovery Among Well-Trained Male Endurance Runners

Introduction: The aim of the present study was to investigate the effect of the depth of cold water immersion (CWI) (whole-body with head immersed and partial-body CWI) after high-intensity, intermittent running exercise on sleep architecture and recovery kinetics among well-trained runners. Methods: In a randomized, counterbalanced order, 12 well-trained male endurance runners ( V . O₂max = 66.0 ± 3.9 ml·min^-1·kg^-1) performed a simulated trail (≈18:00) on a motorized treadmill followed by CWI (13.3 ± 0.2°C) for 10 min: whole-body immersion including the head (WHOLE; n = 12), partial-body immersion up to the iliac crest (PARTIAL; n = 12), and, finally, an out-of-water control condition (CONT; n = 10). Markers of fatigue and muscle damage-maximal voluntary isometric contraction (MVIC), countermovement jump (CMJ), plasma creatine kinase [CK], and subjective ratings-were recorded until 48 h after the simulated trail. After each condition, nocturnal core body temperature (T _core) was measured, whereas sleep and heart rate variability were assessed using polysomnography. Results: There was a lower T _core induced by WHOLE than CONT from the end of immersion to 80 min after the start of immersion (p < 0.05). Slow-wave sleep (SWS) proportion was higher (p < 0.05) during the first 180 min of the night in WHOLE compared with PARTIAL. WHOLE and PARTIAL induced a significant (p < 0.05) decrease in arousal for the duration of the night compared with CONT, while only WHOLE decreased limb movements compared with CONT (p < 0.01) for the duration of the night. Heart rate variability analysis showed a significant reduction (p < 0.05) in RMSSD, low frequency (LF), and high frequency (HF) in WHOLE compared with both PARTIAL and CONT during the first sequence of SWS. No differences between conditions were observed for any markers of fatigue and muscle damage (p > 0.05) throughout the 48-h recovery period. Conclusion: WHOLE reduced arousal and limb movement and enhanced SWS proportion during the first part of the night, which may be particularly useful in the athlete's recovery process after exercise. Future studies are, however, required to assess whether such positive sleep outcomes may result in overall recovery optimization.

Methodological Considerations for Furthering the Understanding of Constraints in Applied Sports

Commonly classified as individual, task or environmental, constraints are boundaries which shape the emergence of functional movement solutions. In applied sport, an ongoing challenge is to improve the measurement, analysis and understanding of constraints to key stakeholders. Methodological considerations for furthering these pursuits should be centred around an interdisciplinary approach. This integration of methodology and knowledge from different disciplines also encourages the sharing of encompassing principles, concepts, methods and data to generate new solutions to existing problems. This narrative review discusses how a number of rapidly developing fields are positioned to help guide, support and progress an understanding of sport through constraints. It specifically focuses on examples from the fields of technology, analytics and perceptual science. It discusses how technology is generating large quantities of data which can improve our understanding of how constraints shape the movement solutions of performers in training and competition environments. Analytics can facilitate new insights from numerous and complex data through enhanced non-linear and multivariate analysis techniques. The role of the perceptual sciences is discussed with respect to generating outputs from analytics that are more interpretable for the end-user. Together, these three fields of technology, analytics and perceptual science may enable a more comprehensive understanding of constraints in sports performance.

Effects of two nights of sleep deprivation on executive function and central and peripheral fatigue during maximal voluntary contraction lasting 60s

PURPOSEː: The current study aimed at assessing the effect of a trial of two nights of sleep deprivation (SDT) on mood, sleepiness, motivation and cognitive and motor performance. METHODSː: Thirty-six healthy young and physically active adult men (17 in the control group and 19 in the SDT group) completed a 48-h control or 48-h SDT. For the SDT, participants did not sleep for 48 h. Executive function (attention and inhibitory control) in the Go/No-Go and Stroop tests, mood, sleepiness, motivation, heart rate variability (HRV), motor performance in a hand grip strength test, and 60-s maximal isometric contraction (MVC-60 s) of knee extension were evaluated at 9-11 am on consecutive days 1, 2, and 3. RESULTS: One night of sleep deprivation increased sleepiness, decreased mood, motivation and motor endurance but did not affect executive function (as measured in the Stroop and Go/No-Go tests), the MVC for hand and leg knee extensor muscles, and peripheral motor fatigue in the leg MVC-60 s task. However, the central activation ratio (CAR) decreased significantly during the MVC-60 s. The SDT significantly contributed to the decrease in these functions. That is, the SDT reduced executive function (increased reaction time during Go/No-Go test), MVC of knee extension, and the CAR before and after the MVC-60 s. By contrast, the SDT did not increase CAR immediately after the MVC-60 s and did not decrease the rate of torque development (RTD). CONCLUSIONSː: The SDT significantly impaired mood, motivation and increased sleepiness and HRV, reduced MVC of knee extensor muscles (but not RTD) and motor performance during the MVC-60 s and worsened executive function (attention and inhibitory control) only during the Go/No-Go task. However, the SDT did not reduce hand grip strength and CAR immediately after the MVC-60 s of knee extensor muscles.

Influence of Training Schedules on Objective Measures of Sleep in Adolescent Academy Football Players

Brown, GA, Veith, S, Sampson, JA, Whalan, M, and Fullagar, HHK. Influence of training schedules on objective measures of sleep in adolescent academy football players. J Strength Cond Res 34(9): 2515-2521, 2020-Football academy settings may pose risks to adolescent athletes achieving sufficient sleep because of the contextual challenges these players face (e.g., psychosocial pressure, changes in training, competition, and academic stress). Given the importance of sleep to overall health as well as physical athletic development and injury risk, this study aimed to investigate whether differences in training schedules (morning vs. evening training sessions) affected objective measures of sleep in adolescent academy football (soccer) players. Twelve academy players (mean age 14.18 ± 1.36 years) wore an ActiGraph accelerometer on nights before, and nights of, training days in 2 separate weeks where morning (09:00-11:00 hours) and evening (18:00-20:00 hours) training occurred. Objective sleep parameters and training load data were collected. Night-time sleep periods were categorized as sleep preceding morning training, preceding evening training, or after evening training. One-way univariate and multivariate analyses of variance for repeated measures were performed to determine the impact of the training schedule on sleep. Significance levels were set at p < 0.05. The total sleep time was below the recommended guidelines (<8 hours) across conditions. A large significant effect of the training schedule on time attempted to fall asleep (p = 0.004, effect size [ES] = 0.40) and time of sleep (p = 0.003, ES = 0.41) was present, with post-evening sessions resulting in the latest times. Overall, the players' sleep behavior was resilient to changes in training schedules. However, the low sleep durations (and potential risks to physical performance/injury) suggest that sleep education coupled with practical interventions are required in this cohort.

International society of sports nutrition position stand: caffeine and exercise performance

Following critical evaluation of the available literature to date, The International Society of Sports Nutrition (ISSN) position regarding caffeine intake is as follows: 1. Supplementation with caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions. 2. Aerobic endurance appears to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use, although the magnitude of its effects differs between individuals. 3. Caffeine has consistently been shown to improve exercise performance when consumed in doses of 3-6 mg/kg body mass. Minimal effective doses of caffeine currently remain unclear but they may be as low as 2 mg/kg body mass. Very high doses of caffeine (e.g. 9 mg/kg) are associated with a high incidence of side-effects and do not seem to be required to elicit an ergogenic effect. 4. The most commonly used timing of caffeine supplementation is 60 min pre-exercise. Optimal timing of caffeine ingestion likely depends on the source of caffeine. For example, as compared to caffeine capsules, caffeine chewing gums may require a shorter waiting time from consumption to the start of the exercise session. 5. Caffeine appears to improve physical performance in both trained and untrained individuals. 6. Inter-individual differences in sport and exercise performance as well as adverse effects on sleep or feelings of anxiety following caffeine ingestion may be attributed to genetic variation associated with caffeine metabolism, and physical and psychological response. Other factors such as habitual caffeine intake also may play a role in between-individual response variation. 7. Caffeine has been shown to be ergogenic for cognitive function, including attention and vigilance, in most individuals. 8. Caffeine may improve cognitive and physical performance in some individuals under conditions of sleep deprivation. 9. The use of caffeine in conjunction with endurance exercise in the heat and at altitude is well supported when dosages range from 3 to 6 mg/kg and 4-6 mg/kg, respectively. 10. Alternative sources of caffeine such as caffeinated chewing gum, mouth rinses, energy gels and chews have been shown to improve performance, primarily in aerobic exercise. 11. Energy drinks and pre-workout supplements containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance.

Sleep quality and military training injury during basic combat training: a prospective cohort study of Chinese male recruits

OBJECTIVE

To examine the association between sleep quality and military training injury (MTI) in recruits during basic combat training (BCT).

METHODS

Participants were new recruits undergoing 12-week military BCT in China. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI) . Participants were classified into two groups based on their sleep quality (group 1, good sleep, PSQI score <7; group 2, poor sleep, PSQI score ≥7) at the start of BCT. Logistic regression analysis was conducted to test whether baseline PSQI score was associated with MTI incidence during BCT.

RESULTS

A total of 563 participants were included. The incidence of MTI was significantly lower in group 1 (48/203, 23.6%) than in group 2 (150/360, 41.7%) (p<0.001). Logistic regression analysis showed that the odds of MTI were 2.307 times higher in group 2 than in group 1 without adjusting for confounders: OR=2.307, p<0.001. When the model was adjusted for age, ethnicity, educational level and family income (OR=2.285) or for the previous confounders plus body mass index (OR=2.377), the results were similar (both p<0.001). Analysis of the types of initial MTI showed that group 2 had about 2.1 times higher odds of soft tissue injury than group 1 (p<0.001 in all the three models).

CONCLUSION

Sleep quality before BCT influences the incidence of MTI, especially of soft tissue injury.

Improving Sleep in Intensive Care Unit: An Overview of Diagnostic and Therapeutic Options

Good quality sleep is considered to be essential for healthy living and recovering from illness. It would be logical to think that good quality sleep is most required when a patient is critically ill in an intensive care unit (ICU). Several studies have demonstrated poor quality of sleep while the patients are in ICU. Subjective tools such as questionnaires while simple are unreliable to accurately assess sleep quality. Relatively few studies have used standardized polysomnography. The use of novel biological markers of sleep such as serum brain-derived neurotrophic factor concentrations may help in conjunction with polysomnography to assess sleep quality in critically ill patients. Attempts to improve sleep included nonpharmacological interventions including the use of earplugs, eye sleep masks, and pharmacological agents including ketamine, propofol, dexmedetomidine, and benzodiazepines. The evidence for these interventions remains unclear. Further research is needed to assess quality of sleep and improve the sleep quality in intensive care settings.

The prevalence of non-contact muscle injuries of the lower limb in professional soccer players who perform Salah regularly: a retrospective cohort study

Background

The present study assessed the prevalence of non-contact muscle injuries of the lower limbs, including hamstring injuries, in professional Russian soccer players who regularly perform Salah, an obligatory Muslim prayer performed 5 times a day.

Methods

Using a retrospective cohort study design, 68 professional male soccer players (excluding goalkeepers), 34 of whom were Muslims regularly performing Salah (exposure group) and 34 were randomly chosen non-Muslim players (control group), were included in the study. The groups were similar in their playing leagues, field positions, age (27 ± 3.1 vs 28 ± 4.2 years), and body mass index (22 ± 1.2 vs 23 ± 0.92 kg/m²).

Results

The incidence of hamstring injury was significantly lower in the exposure group (2 vs 14, p = 0.0085). A declining trend for the number of muscle injuries (either hamstring or not) was observed in the exposure group (11 vs 27, p = 0.0562). Two players in the exposure group and 11 in the control group (p = 0.0115, OR 0.1307, 95% CI 0.0276 to 0.5698) suffered a hamstring injury, with no statistically significant difference in the occurrence of other injuries. The total amount of the training and play days missed because of hamstring and other muscle injuries was significantly lower in the exposure group (24 vs 213 days, p = 0.0043, and 200 vs 344 days, p = 0.0066, respectively).

Conclusion

The prevalence of non-contact muscle injuries, including hamstring injuries, was lower in professional Russian soccer players who regularly performed Salah.

Partial sleep deprivation affects endurance performance and psychophysiological responses during 12-minute self-paced running exercise

PURPOSE

This study aimed to investigate the effects of partial sleep deprivation (PSD) on physical performance and psychophysiological responses during 12-minute self-paced running exercise.

METHODS

Twenty runners (20.8±1.1 years, 70.6±4.9 kg, 175.1±3.9 cm) performed, in a randomized order, two running self-paced field exercises after a normal sleep night (CONT, bedtime from 22:30 h to 06:30 h) and one night of PSD (bedtime from 00:30 h to 04:30 h). Core temperature and motivation were recorded before exercise. Speed, covered distance, heart rate (HR), rating of perceived exertion (RPE) and respiratory parameters (i.e., minute ventilation (VE), oxygen uptake (VO₂) and carbon dioxide production (VCO₂)) were assessed during exercise. Blood lactate concentration [La] was assessed 2 min after exercise. Simple reaction time (SRT), mood and barrage test (BT) were assessed before and after exercise.

RESULTS

Higher RPE (p=0.01, d=0.90) and lower physical performance (i.e., p=0.001, d=0.59 for running speed and p=0.01, d=0.7 and Δ (%)=-6% for covered distance), following PSD, were obtained compared to CONT. Similarly, PSD attenuated core temperature (p=0.01, d=0.84), HR (p=0.006, ɳp²=0.45), VE (p=0.001, ɳp²=0.73), VO₂ (p=0.001, ɳp²=0.96), BT (p<0.0005, ɳp²=0.86), SRT (p=0.0009, ɳp²=0.44) and mood (p<0.0005). However, VCO₂, [La] and motivation score were not affected by sleep conditions.

CONCLUSION

The decrease of running performance and the increase of physical discomfort after PSD could be the origin of the lower cardio-respiratory responses to the 12-minute self-paced exercise. Effective strategies should be introduced to overcome the deterioration of physical performance and physiological responses after PSD.

Potential use of actigraphy to measure sleep in monkeys: comparison with behavioral analysis from videography

Sleep is indispensable for human health, with sleep disorders initiating a cascade of negative consequences. As our closest phylogenetic relatives, non-human primates (NHPs) are invaluable for comparative sleep studies and exhibit tremendous potential for improving our understanding of human sleep and related disorders. Previous work on measuring sleep in NHPs has mostly used electroencephalography or videography. In this study, simultaneous videography and actigraphy were applied to observe sleep patterns in 10 cynomolgus monkeys ( Macaca fascicularis) over seven nights (12 h per night). The durations of wake, transitional sleep, and relaxed sleep were scored by analysis of animal behaviors from videography and actigraphy data, using the same behavioral criteria for each state, with findings then compared. Here, results indicated that actigraphy constituted a reliable approach for scoring the state of sleep in monkeys and showed a significant correlation with that scored by videography. Epoch-by-epoch analysis further indicated that actigraphy was more suitable for scoring the state of relaxed sleep, correctly identifying 97.57% of relaxed sleep in comparison with video analysis. Only 34 epochs (0.13%) and 611 epochs (2.30%) were differently interpreted as wake and transitional sleep compared with videography analysis. The present study validated the behavioral criteria and actigraphy methodology for scoring sleep, which can be considered as a useful and a complementary technique to electroencephalography and/or videography analysis for sleep studies in NHPs.

Influence of Faster and Slower Recovery-Profile Classifications, Self-Reported Sleep, Acute Training Load, and Phase of the Microcycle on Perceived Recovery in Futsal Players

PURPOSE

To determine whether daily perceived recovery is explained from a multifactorial single-session classification of recovery (ie, faster vs slower) or other circumstantial factors (ie, previous training load, self-reported sleep, or phase of the microcycle).

METHODS

Nineteen elite male futsal players were initially allocated to a recovery-classification group (faster recovery, slower physiological, or slower perceptual) based on previous research using a multifactorial cluster-analysis technique. During 4 ensuing weeks of preseason, training loads were monitored via player load, training impulse, and session rating of perceived exertion. Before each day's training, players reported their perception of recovery (Total Quality of Recovery scale [TQR]) and the number of hours and perceived quality of sleep the night prior. A hierarchical linear mixed model was used to analyze the effect of the different recovery profiles, training load, sleep, and phase of the microcycle (ie, start, middle, end) on daily TQR.

RESULTS

The recovery classification of players (P = .20), training load (training impulse, P = .32; player load, P = .23; session rating of perceived exertion, P = .46), and self-reported hours slept the night before (P = .45) did not significantly influence TQR. However, perceived sleep quality (P < .01) and phase of the microcycle (P < .01) were significantly associated with TQR (r2 = .41).

CONCLUSIONS

Neither recovery classification nor prior training load influenced perceived recovery during the preseason. However, higher TQR was evident with better self-reported sleep quality, whereas lower values were associated with phases of the training week.

Acoustic closed-loop stimulation during sleep improves consolidation of reward-related memory information in healthy children but not in children with attention-deficit hyperactivity disorder

Study Objectives

Slow oscillations (SO) during slow-wave sleep foster the consolidation of declarative memory. Children with attention-deficit hyperactivity disorder (ADHD) display deficits in the sleep-associated consolidation of declarative memory, possibly due to an altered function of SO. The present study aimed at enhancing SO activity using closed-looped acoustic stimulation during slow-wave sleep in children with ADHD.

Methods

A total of 29 male children (14 with ADHD; aged 8–12 years) participated in a double-blind, placebo-controlled study trial. Children spent two experimental nights in a sleep lab, one stimulation night and one sham night. A declarative learning task (word-pair learning) with a reward condition was used as a primary outcome. Secondary outcome variables were a procedural memory (serial reaction time) and working memory (WM; n-back) task. Encoding of declarative and procedural memory took place in the evening before sleep. After sleep, the retrieval took place followed by the n-back task.

Results

The stimulation successfully induced SO activity during sleep in children with and without ADHD. After stimulation, only healthy children performed better on high-rewarded memory items (primary outcome). In contrast, there were indications that only children with ADHD benefitted from the stimulation with respect to procedural as well as WM performance (secondary outcome).

Conclusions

We were able to show that the acoustic closed-loop stimulation can be applied to enhance SO activity in children with and without ADHD. Our data indicate that SO activity during sleep interacts with subsequent memory performance (primary outcome: rewarded declarative memory; secondary outcome: procedural and WM) in children with and without ADHD.

The effect of night-time exercise on sleep architecture among well-trained male endurance runners

The aim of the present study was to investigate the effects of night-time (21:00 hours) high-intensity, intermittent exercise on sleep architecture among well-trained athletes in a laboratory setting. In a randomized, counterbalanced order, 11 well-trained male runners completed a simulated trail-running exercise (TRAIL) on a motorized treadmill and a resting condition (REST; no exercise during the day). After each condition, nocturnal autonomic nervous system activity and core body temperature (CBT) were measured and sleep was analysed using polysomnography and actigraphy. Markers of muscle damage (maximal voluntary contraction [MVC], plasma creatine kinase concentration [CK] and perceived muscle soreness) were recorded before and immediately (POST), 24 hr (H24) and 48 hr (H48) after exercise. TRAIL induced a high level of fatigue and mild exercise-induced muscle damage, as determined by a reduction in MVC (-9.4%, p < .01, d = -1.36) and increases in [CK] (+176.0%, p < .01, d = 1.49) and perceived muscle soreness (+4.5 UA, p < .01, d = 2.17) compared with REST at H24. A trend for increased non-rapid eye movement (+4.2%; p = .10; d = 0.86) and reduced rapid eye movement (-4.4%; p = .07; d = -0.87) during sleep was observed for TRAIL compared with the REST condition. Moreover, compared with REST, TRAIL significantly increased CBT and nocturnal HR during the first part of the night. In conclusion, sleep architecture was modified after night-time, high-intensity exercise among well-trained runners.

Sleep Quality and Quantity of International Rugby Sevens Players During Pre-season

Leduc, C, Jones, B, Robineau, J, Piscione, J, and Lacome, M. Sleep quality and quantity of international rugby sevens players during pre-season. J Strength Cond Res 33(7): 1878-1886, 2019-The aim of this study was to investigate the influence of training load on objective and subjective sleep measures among elite rugby sevens players during pre-season. Nine international male rugby sevens players participated in this study. Actigraphic and subjective sleep assessment were performed on a daily basis to measure sleep parameters. Training load was measured during the entire pre-season period, and sleep data from the highest and lowest training load week were used in the analysis through magnitude-based inferences. During the highest training load, likely to possibly small, moderate decreases in time in bed (effect sizes; ±90% confidence limits: -0.42; ±0.44 for session rating of perceived exertion [sRPE], -0.69; ±0.71 for total distance covered [TDC]) and total sleep time (-0.20; ±0.37 for sRPE, -0.23; ±0.35 for TDC) were found. Possibly small (-0.21; ±0.35 for high-speed distance, -0.52; ±0.73 for acceleration/deceleration [A/D]) and likely moderate (-074; ±0.67 for TDC) decreases were observed in subjective sleep quality. Possibly small to very likely moderate changes in sleep schedule were observed. Sleep quantity and subjective quality seem to be deteriorated during higher loads of training. This study highlights the necessity to monitor and improve sleep among elite rugby sevens players, especially for the intense period of training.

Effects of Exercise Domain and Intensity on Sleep in Women and Men with Overweight and Obesity

Inadequate sleep is associated with cardiometabolic risk and adiposity. Exercise has been suggested as an efficient strategy to improve sleep; however, the effects of different types of exercise on sleep in individuals with overweight and obesity are not well understood. We examined effects of active commuting and leisure-time exercise on sleep in individuals with overweight or obesity. 130 physically inactive adults (20-45 years) with overweight or class 1 obesity (body mass index: 25-35 kg/m²) were randomized to 6 months of habitual lifestyle (CON, n = 18), active commuting by bike (BIKE, n = 35), or leisure-time exercise of moderate intensity (MOD, 50% VO₂peak-reserve, n = 39) or vigorous intensity (VIG, 70% VO₂peak-reserve, n = 38), 5 days/week. Sleep was assessed from 7-day/night accelerometry and questionnaires at baseline, 3 months, and 6 months. 92 participants were included in a per protocol analysis. At 3 months, sleep duration was longer in VIG (29 min/night [3; 55] (mean [95% CI]), p=0.03) but not in BIKE and MOD (p ≥ 0.11) compared with CON and was not different between groups at 6 months (p ≥ 0.36 vs. CON). At 6 months, sleep duration variability was lower in MOD (-31% [-50; -3], p=0.03) and numerically lower in VIG (-28% [-49; 1], p=0.06) relative to CON but was unchanged in BIKE (p=0.17 vs. CON). The effects were, however, primarily attributable to shorter and more irregular sleep in CON over time. Our findings suggest that effects of exercise on sleep in individuals with overweight and obesity may be restricted to leisure-time exercise with a short-term effect on sleep duration after vigorous intensity exercise (3 months) but a more regular sleep pattern after 6 months of moderate and vigorous intensity exercise compared with physically inactive controls. This trial was registered at clinicaltrials.gov with ID NCT01962259.

Poor sleep is related to lower general health, increased stress and increased confusion in elite Gaelic athletes

OBJECTIVES

Persistent poor sleep is associated with a range of adverse health outcomes. Sleep is considered the main method of recovery in athletes; however, studies report that a significant number of athletes are getting insufficient sleep. The purpose of this study was to assess the sleep profiles of elite Gaelic athletes and to compare wellbeing in those with poor sleep and those with good sleep.

METHODS

69 elite Gaelic athletes completed questionnaires, including the Pittsburgh Sleep Quality Index (PSQI), Subjective Health Complaints Inventory (SHC), Nordic Musculoskeletal Questionnaire (NMQ), stress subscale of the Depression Anxiety Stress Scale (DASS), the tension-anxiety, anger-hostility and confusion-bewilderment subscales of the Profile of Mood States (POMS) as well as the catastrophising subscale of the Coping Strategies Questionnaire (CSQ). Participants were categorised into poor sleepers (PSQI ≥5) and good sleepers (PSQI <5) and outcome measures of health and wellbeing were analysed between the two groups.

RESULTS

47.8% of athletes were poor sleepers. Self-reported sleep duration was 7.5 ± 0.6 h per night. 63.7% of poor sleepers took >30 min to fall asleep, compared to 5.6% of good sleepers. Poor sleepers had significantly lower general health (SHC) (p = 0.029), increased stress (DASS) (p = 0.035) and increased confusion (POMS-subscale) (p = 0.005). There was no significant difference between groups for number of painful body parts (NMQ) (p = 0.052), catastrophising (CSQ) (p = 0.287), overall mood (POMS) (p = 0.059), or POMS subscales of anger (p = 0.346) or tension (p = 0.593).

CONCLUSION

Nearly 50% of elite Gaelic athletes report poor sleep. There is a significant relationship between poor sleep and lower general health, increased stress and increased confusion, and these factors may interact with each other. Monitoring of and interventions to enhance sleep may be required to improve athletes' wellbeing.