Sleep and the Young Athlete.

CONTEXT: Sleep plays a vital role in cognitive and physical performance. Teenage athletes (ages 13-19 years) are considered especially at risk for disordered sleep and associated negative cognitive, physical, and psychosomatic effects. However, there is a paucity of evidence-based recommendations to promote sleep quality and quantity in athletes who fall within this age range. We performed a review of the literature to reveal evidence-based findings and recommendations to help sports instructors, athletic trainers, physical therapists, physicians, and other team members caring for young athletes provide guidance on sleep optimization for peak sports performance and injury risk reduction. METHODS: PubMed, Scopus, and Cochrane CENTRAL were searched on May 11, 2016, and then again on September 1, 2020, for relevant articles published to date. STUDY DESIGN: Narrative review. LEVEL OF EVIDENCE: Level 4. RESULTS: Few studies exist on the effects disordered sleep may have on teenage athletes. By optimizing sleep patterns in young athletes during training and competitions, physical and mental performance, and overall well-being, may be optimized. Adequate sleep has been shown to improve the performance of athletes, although further studies are needed. CONCLUSION: Twenty-five percent of total sleep time should be deep sleep, with a recommended sleep time of 8 to 9 hours for most young athletes. Screen and television use during athletes' bedtime should be minimized to improve sleep quality and quantity. For young athletes who travel, jet lag can be minimized by allowing 1 day per time zone crossed for adjustment, limiting caffeine intake, planning meals and onboard sleeping to coincide with destination schedules, timing arrivals in the morning whenever possible, and using noise-canceling headphones and eyeshades. STRENGTH-OF-RECOMMENDATION TAXONOMY (SORT): B.

Air travellers' experiences and understanding of jetlag and perceptions of management strategies: a qualitative study.

Jetlag is largely self-managed by the individual traveller. This paper explores the lived experiences of air travellers, their understanding of jetlag, and their perceptions of management strategies. 32 international travellers (mean age = 31, SD: 15 years; 47% female, mean flight duration = 16, SD: 6 hours) were interviewed. Interviews were recorded, transcribed verbatim and analysed using the Framework Approach. Analysis of the qualitative data revealed three emergent themes: Travel beliefs and experiences, Impact of jetlag, and Approaches to jetlag management. Participants' experience of jetlag was described in terms of the entire journey with no distinction made between circadian disruption and travel fatigue. Management strategies revolved around needs for comfort and avoiding fatigue, and were mostly guided by somatic symptom cues, prior travel experiences, or the experiential advice from others. Our findings highlight the need for traveller involvement in co-designing evidence-based interventions for jetlag to enhance their transferability into the real world. Practitioner summaryQualitative findings highlighted jetlag as encapsulating the entire journey, and not limited to post-flight circadian disruptions during international travel. Jetlag management interventions need to address issues of circadian misalignment together with travel fatigue and in-flight discomfort through behavioural and nutritional strategies. Travel context and environmental factors such as airport facilities also influenced perceived jetlag severity.

Time-Restricted Feeding in Mice Prevents the Disruption of the Peripheral Circadian Clocks and Its Metabolic Impact during Chronic Jetlag.

We used time-restricted feeding (TRF) to investigate whether microbial metabolites and the hunger hormone ghrelin can become the dominant entraining factor during chronic jetlag to prevent disruption of the master and peripheral clocks, in order to promote health. Therefore, hypothalamic clock gene and Agrp/Npy mRNA expression were measured in mice that were either chronically jetlagged and fed ad libitum, jetlagged and fed a TRF diet, or not jetlagged and fed a TRF diet. Fecal short-chain fatty acid (SCFA) concentrations, plasma ghrelin and corticosterone levels, and colonic clock gene mRNA expression were measured. Preventing the disruption of the food intake pattern during chronic jetlag using TRF restored the rhythmicity in hypothalamic clock gene mRNA expression of Reverbα but not of Arntl. TRF countered the changes in plasma ghrelin levels and in hypothalamic Npy mRNA expression induced by chronic jetlag, thereby reestablishing the food intake pattern. Increase in body mass induced by chronic jetlag was prevented. Alterations in diurnal fluctuations in fecal SCFAs during chronic jetlag were prevented thereby re-entraining the rhythmic expression of peripheral clock genes. In conclusion, TRF during chronodisruption re-entrains the rhythms in clock gene expression and signals from the gut that regulate food intake to normalize body homeostasis.

Jet-Lag Countermeasures Used by International Business Travelers.

INTRODUCTION: Research has highlighted the significant impact that jet lag can have upon performance, health, and safety. International business travelers have an important role in economic growth; however, there is a lack of research investigating jet lag and jet-lag management in international business travelers. This study aimed to investigate international business travelers use of jet-lag countermeasures. METHODS: International business travelers from Australia (N = 107) participated in a survey examining use of jet-lag countermeasures (pharmacological and nonpharmacological). Chi-squared tests were conducted examining the association between duration of stay and traveling experience on jet-lag countermeasure use. RESULTS: Most subjects had traveled for business for less than 15 yr and 57% reported taking between 14 trips annually. Durations of stay averaged 10 d (SD 13 d). Nonpharmacological countermeasure use was high. Pharmacological countermeasure use was less common. There were no significant associations between duration of stay and countermeasure implementation. Travel experience was only associated with nonpharmacological countermeasures after arrival home. CONCLUSION: Education programs delivered through businesses would be beneficial for providing information on jet lag, its implications, and recommended countermeasures to travelers. Rigney G, Walters A, Bin YS, Crome E, Vincent GE. Jet-lag countermeasures used by international business travelers. Aerosp Med Hum Perform. 2021; 92(10):825830.

Managing Travel Fatigue and Jet Lag in Athletes: A Review and Consensus Statement.

Athletes are increasingly required to travel domestically and internationally, often resulting in travel fatigue and jet lag. Despite considerable agreement that travel fatigue and jet lag can be a real and impactful issue for athletes regarding performance and risk of illness and injury, evidence on optimal assessment and management is lacking. Therefore 26 researchers and/or clinicians with knowledge in travel fatigue, jet lag and sleep in the sports setting, formed an expert panel to formalise a review and consensus document. This manuscript includes definitions of terminology commonly used in the field of circadian physiology, outlines basic information on the human circadian system and how it is affected by time-givers, discusses the causes and consequences of travel fatigue and jet lag, and provides consensus on recommendations for managing travel fatigue and jet lag in athletes. The lack of evidence restricts the strength of recommendations that are possible but the consensus group identified the fundamental principles and interventions to consider for both the assessment and management of travel fatigue and jet lag. These are summarised in travel toolboxes including strategies for pre-flight, during flight and post-flight. The consensus group also outlined specific steps to advance theory and practice in these areas.

Business Class Travel Preserves Sleep Quality and Quantity and Minimizes Jet Lag During the ICC Women's T20 World Cup.

PURPOSE: To determine the impact of the quality and quantity of sleep during an international flight on subsequent objective sleep characteristics, training and match-day load, self-reported well-being, and perceptions of jet lag of elite female cricketers during an International Cricket Council Women's T20 World Cup. METHODS: In-flight and tournament objective sleep characteristics of 11 elite female cricketers were assessed using activity monitors. Seated in business class, players traveled west from Melbourne, Australia, to Chennai, India. The outbound flight departed Melbourne at 3:30 AM with a stopover in Dubai for 2 hours. The arrival time in Chennai was 8:10 PM local time (1:40 AM in Melbourne). The total travel time was 19 hours 35 minutes. Perceptual ratings of jet lag, well-being, and training and competition load were collected. To determine the impact of in-flight sleep on tournament measures, a median split was used to create subsamples based on (1) in-flight sleep quantity and (2) in-flight sleep quality (2 groups: higher vs lower). Spearman correlation coefficients were calculated to assess the bivariate associations between sleep measures, self-reported well-being, perceptual measures of jet lag, and internal training and match-day load. RESULTS: Mean duration and efficiency of in-flight sleep bouts were 4.72 hours and 87.45%, respectively. Aggregated in-flight sleep duration was 14.64 + 3.56 hours. Players with higher in-flight sleep efficiency reported higher ratings for fatigue (ie, lower perceived fatigue) during the tournament period. Tournament sleep duration was longer, and bed and wake times were earlier compared with habitual. Compared with other nights during the tournament, sleep duration was shorter following matches. CONCLUSIONS: Maximizing in-flight sleep quality and quantity appears to have implications for recovery and sleep exhibited during competition. Sleep duration was longer than habitual except for the night of a match, which suggests that T20 matches may disrupt sleep duration.

Efficacy of Functional Foods, Beverages, and Supplements Claiming to Alleviate Air Travel Symptoms: Systematic Review and Meta-Analysis.

Airline passengers experience a range of symptoms when travelling on long flights. This review evaluated the efficacy of functional foods, beverages, and supplements claiming to address the effects of air travel for healthy adults. Products were identified in a scoping review of electronic databases, search engines, and grey literature (March to August 2019). A systematic review of the efficacy of product ingredients was conducted using five electronic databases from inception to February 2021. Articles were screened, data extracted, and assessed for risk of bias by two researchers independently. Meta-analysis was performed. Of the 3842 studies identified, 23 met selection criteria: melatonin (n = 10), Pycnogenol (n = 4), various macronutrients (n = 2), caffeine (n = 2), Centella asiatica (n = 1), elderberry (n = 1), Echinacea (n = 1), fluid (n = 1), and Pinokinase (n = 1). Meta-analysis (random effects model) indicated melatonin reduced self-reported jetlag following eastbound (n = 5) and westbound (n = 4) flights: standard mean difference -0.76 (95% CI = -1.06 to -0.45, I2 0%, p < 0.00001) and -0.66 (95% CI = -1.07 to -0.26, I2 45%, p = 0.001), respectively. Pycnogenol also reduced edema scores (n = 3), standard mean -4.09 (95% CI = -6.44 to -1.74), I2 98%, p = 0.0006). Overall, 12 of 183 ingredients contained in 199 products had evidence to support claims.

Sleep Hygiene and Light Exposure Can Improve Performance Following Long-Haul Air Travel.

PURPOSE: To assess the efficacy of a combined light exposure and sleep hygiene intervention to improve team-sport performance following eastward long-haul transmeridian travel. METHODS: Twenty physically trained males underwent testing at 09:00 and 17:00 hours local time on 4 consecutive days at home (baseline) and the first 4 days following 21 hours of air travel east across 8 time zones. In a randomized, matched-pairs design, participants traveled with (INT; n = 10) or without (CON; n = 10) a light exposure and sleep hygiene intervention. Performance was assessed via countermovement jump, 20-m sprint, T test, and Yo-Yo Intermittent Recovery Level 1 tests, together with perceptual measures of jet lag, fatigue, mood, and motivation. Sleep was measured using wrist activity monitors in conjunction with self-report diaries. RESULTS: Magnitude-based inference and standardized effect-size analysis indicated there was a very likely improvement in the mean change in countermovement jump peak power (effect size 1.10, ±0.55), and likely improvement in 5-m (0.54, ±0.67) and 20-m (0.74, ±0.71) sprint time in INT compared with CON across the 4 days posttravel. Sleep duration was most likely greater in INT both during travel (1.61, ±0.82) and across the 4 nights following travel (1.28, ±0.58) compared with CON. Finally, perceived mood and motivation were likely worse (0.73, ±0.88 and 0.63, ±0.87) across the 4 days posttravel in CON compared with INT. CONCLUSIONS: Combined light exposure and sleep hygiene improved speed and power but not intermittent-sprint performance up to 96 hours following long-haul transmeridian travel. The reduction of sleep disruption during and following travel is a likely contributor to improved performance.

How do travelers manage jetlag and travel fatigue? A survey of passengers on long-haul flights.

Jetlag and travel fatigue can impair functioning, but it is unknown what strategies are used by travelers to minimize these consequences. Passengers on Qantas Airways flights were invited to take part in online surveys. Long-haul flights of ≥8 h into and out of Australia were targeted, which involved time differences of 1 to 18 h between the origin and destination. Passengers were queried about the use of travel booking choices before the flight, and the use of behavioral strategies before, during, and after flight for reducing jetlag and travel fatigue. Surveys were completed by N = 460 passengers aged 18 to 78 (43% male; mean age 50 y). Selecting a seat location (59%) and choosing a direct flight (52%) were the most common booking strategies. Almost all (99%) employed specific behavioral strategies during flight, with fewer implementing strategies before flight (73%) and after flight (89%). During the journey, 81% consumed or avoided caffeine and alcohol, 68% altered food intake, 68% used comfort/relaxation strategies, 53% light exposure, 35% physical activity, 31% compression stockings, 15% pharmaceutical sleep aids, and 8% melatonin. Surprisingly, only 1 of 460 passengers reported using a jetlag app. Younger travelers were more likely to adopt any strategy before the flight than older travelers (χ 22 = 14.90, p =.01), while female travelers appeared more likely than male travelers to use strategies before (77% vs. 68%) and after flight (91% vs. 85%). Reason for travel, flight cabin, leg of journey, and country of residence were not significantly associated with the use of behavioral strategies. Nearly all passengers took measures to improve the experience and consequences of long-haul flying. The results suggest that interventions around food/drink and physical activity may be highly acceptable to passengers for mitigating travel fatigue and that greater public education on evidence-based strategies may be helpful for reducing travel fatigue and jetlag.

Chocolate for breakfast prevents circadian desynchrony in experimental models of jet-lag and shift-work.

Night-workers, transcontinental travelers and individuals that regularly shift their sleep timing, suffer from circadian desynchrony and are at risk to develop metabolic disease, cancer, and mood disorders, among others. Experimental and clinical studies provide evidence that food intake restricted to the normal activity phase is a potent synchronizer for the circadian system and can prevent the detrimental metabolic effects associated with circadian disruption. As an alternative, we hypothesized that a timed piece of chocolate scheduled to the onset of the activity phase may be sufficient stimulus to synchronize circadian rhythms under conditions of shift-work or jet-lag. In Wistar rats, a daily piece of chocolate coupled to the onset of the active phase (breakfast) accelerated re-entrainment in a jet-lag model by setting the activity of the suprachiasmatic nucleus (SCN) to the new cycle. Furthermore, in a rat model of shift-work, a piece of chocolate for breakfast prevented circadian desynchrony, by increasing the amplitude of the day-night c-Fos activation in the SCN. Contrasting, chocolate for dinner prevented re-entrainment in the jet-lag condition and favored circadian desynchrony in the shift-work models. Moreover, chocolate for breakfast resulted in low body weight gain while chocolate for dinner boosted up body weight. Present data evidence the relevance of the timing of a highly caloric and palatable meal for circadian synchrony and metabolic function.

Sleep Hygiene for Optimizing Recovery in Athletes: Review and Recommendations.

For elite athletes who exercise at a high level, sleep is critical to overall health. Many studies have documented the effects of sleep deprivation in the general population, but few studies exist regarding specific effects in the athlete. This review summarizes the effects of sleep deprivation and sleep extension on athletic performance, including reaction time, accuracy, strength and endurance, and cognitive function. There are clear negative effects of sleep deprivation on performance, including reaction time, accuracy, vigor, submaximal strength, and endurance. Cognitive functions such as judgment and decision-making also suffer. Sleep extension can positively affect reaction times, mood, sprint times, tennis serve accuracy, swim turns, kick stroke efficiency, and increased free throw and 3-point accuracy. Banking sleep (sleep extension prior to night of intentional sleep deprivation before sporting event) is a new concept that may also improve performance. For sports medicine providers, the negative effects of sleep deprivation cannot be overstated to athletes. To battle sleep deprivation, athletes may seek supplements with potentially serious side effects; improving sleep quality however is simple and effective, benefiting not only athlete health but also athletic performance.

Jetlag related sleep problems and their management: A review.

OBJECTIVES: We reviewed Jetlag, particularly in view of its effects on sleep and how it can be managed. METHODS: The Proquest Central database of Kirikkale University, PubMed and Google scholar were used while searching for the following key words: "Jetlag", "symptoms", "sleep", "melatonin" and "treatment". RESULTS: Flight dysrhythmia, otherwise known as jetlag, is caused by flying globally over various time zones. Most passengers who fly over six or more different time zones generally require 4-6 days after travelling to resume their usual sleep patterns and to feel less lethargic during the day. Signs of jet lag can vary between debilitated awareness, insomnia, feeling tired during the day and frequent waking during the night. During the night our pineal glands excrete a hormone called melatonin; dim lights cause the continuation of excretion of these hormones whereas any exposure to bright lights stems the flow of release. Common precautionary measures are specific diets, bright lights and melatonin agonists (Ramelteon, Agomelatine). CONCLUSION: Sleep issues derived from jetlag were found to be most common in passengers who flew through various time belts. Melatonin assumes a critical part in adjusting the body's circadian rhythms and has been utilized restoratively to re-establish irritated circadian rhythms.

Effects of a 20-Min Nap Post Normal and Jet Lag Conditions on P300 Components in Athletes.

Post-lunch sleepiness belongs to biological rhythms. Athletes take a nap to counteract afternoon circadian nadir, in prevision of disturbed sleep. This study examined the effects of brief post-lunch nap on vigilance in young and healthy athletes. The P300 components, physiological and cognitive performances were assessed either after nap or rest, following a night of normal sleep (NSC) or simulated jet lag condition (5-h advance-JLC). P300 wave is the positive deflection at about 300 ms in response to a rare stimulus, representing higher information processing. P300 amplitude reflects the amount of attention allocated whereas P300 latency reflects time spent on stimulus classification. P300 amplitude was significantly increased (Fz:11.14±3.0vs9.05±3.2 µV; p<0.05) and P300 latency was shorter (Pz:327.16±18.0vs344.90±17.0 ms; p<0.01) after nap in NSC. These changes were accompanied by lower subjective sleepiness (19.7±9.6vs27.5±16.5; p<0.05) and decrease in mean reaction times (MRT: divided attention, 645.1±74.2vs698±80.4 ms; p<0.05). In contrast, in JLC, only P300 amplitudes (Fz:10.30±3.1vs7.54±3.3 µV; p<0.01 and Cz: 11.48±3.1vs9.77±3.6 µV; p<0.05) increased but P300 latencies or MRT did not improve. These results indicated improvements in speed of stimulus evaluation time. Napping positively impacts on cognitive processing, especially when subjects are on normal sleep schedules. A nap should be planned for athletes whose performance requires speedy and accurate decisions.

Is There a Doctor Onboard? Medical Emergencies at 40,000 Feet.

It is estimated 2.75 billion people travel aboard commercial airlines every year and 44,000 in-flight medical emergencies occur worldwide each year. Wilderness medicine requires a commonsense and improvisational approach to medical issues. A sudden call for assistance in the austere and unfamiliar surroundings of an airliner cabin may present the responding medical professional with a "wilderness medicine" experience. From resource management to equipment, this article sheds light on the unique conditions, challenges, and constraints of the flight environment.

Preparing for International Travel and Global Medical Care.

Thorough pretravel preparation and medical consultation can mitigate avoidable health and safety risks. A comprehensive pretravel medical consultation should include an individualized risk assessment, immunization review, and discussion of arthropod protective measures, malaria prophylaxis, traveler's diarrhea, and injury prevention. Travel with children and jet lag reduction require additional planning and prevention strategies; travel and evacuation insurance may prove essential when traveling to less resourced countries. Consideration should also be given to other high-risk travel scenarios, including the provision of health care overseas, adventure and extreme sports, water environments and diving, high altitude, and terrorism/unstable political situations.