Is Travel Associated With Match Performance in Elite North American Professional Soccer? An Exploratory Study.

PURPOSE: Travel fatigue impacts cognitive and physiologic systems, but its association with elite soccer match performance is unclear. In this retrospective observational study, we aimed to explore the association between travel and match outcomes in elite North American soccer. METHODS: Travel data and match outcomes (team points or goals scored and conceded) and physical performance outcomes from 26 elite professional soccer teams and their players were analyzed (148 matches [team-based data] and 1252 player matches from 297 players; age 22.7 [4.5] y). Player- and match-level correlations between performance measures and both acute and cumulated travel metrics were analyzed. RESULTS: Cumulative travel metrics were positively associated with team (travel distance [r = .20; 95% CI, .03-.25], travel time [r = .20; .06-.37], and time away [r = .20; .06-.37]) and individual player (travel distance, [r = .14; .08-.19], travel time [r = .17-.23], and time away [r = .13; .07-.18]) high-intensity running. Cumulative time away was negatively associated with team points (r = -.14; -.28 to -.001) and positively associated with goals conceded (r = .14; .01-.27); no clear association between acute travel metrics and match outcomes or physical performance was observed. CONCLUSIONS: As travel cumulated, away teams and their players ran more but for less reward (team points), although the magnitude of these associations was small. These data are exploratory and do not imply a causal relationship; however, further research should consider cumulation of travel.

The type and extent of travel for professional footballers undertaking national team duties for a national football federation.

Elite football (soccer) involves club, continental and international fixtures, requiring players to undertake extensive travel [1]. For a national football federation, this includes the transport of players between club and camp/tournament commitments, which is often a point of contention between respective organisations [2]. Partly this contention results from the effects of travel, whereby jet lag and travel fatigue can negatively affect physical performance [3-5] and athlete wellbeing [6, 7]. Given the scarcity of data on elite players following travel, an initial step for any national football federation is to understand the volume and nature of travel undertaken by national team players. Such insight may better identify the schedule, timelines and needs of athletes' post travel. Better awareness of these travel needs can help maximise availability for training and minimise the impact of travel related stresses on performance or wellbeing. However, the regularity and volume of travel to national football team commitments has not previously been described. Further, travel demands are likely to vary significantly based on the location of the athlete and the national team camp. For countries outside of Europe, such as Australia, the travel demands and ensuing effects on player preparation can be substantial for both arrival into national team and on return to clubs [7]. Hence, detailed information regarding the type, frequency, and extent of travel for national team duties is important to aid in planning optimal travel schedules and interventions to assist players for international or club duty.

Travel Across More Time Zones Results in Worse Perceived Fatigue and Sleep in National-Team Footballers.

PURPOSE: This study investigated the association between (1) time zone difference and (2) travel direction (east vs west) with posttravel changes in perceptual responses of national-team footballers. METHODS: Travel schedules from 355 national-team trips (50 elite soccer players) were verified using an online flight database. All players provided perceptual ratings of fatigue, sleep quality, soreness, and stress to calculate changes in scores up to 2 days after travel. Trips were categorized as <3, 3 to 6, 6 to 9, or 9+ time zone changes, along with travel direction (eastward or westward). The pretravel to posttravel changes in perceptual ratings at days 1 and 2 postarrival were compared between time zone change and travel direction with linear mixed models. RESULTS: For every time zone crossed, poorer ratings of perceptual fatigue (ß = 0.068, P < .001), sleep (ß = 0.095, P < .001), soreness (ß = 0.0049, P < .001), and total wellness (ß = 0.214, P < .001) were observed. However, the models explained only small proportions of the variation in postflight perceptual responses (7%-18%). Regardless, travel across 9+ time zones resulted in significantly worse perceived fatigue, sleep, and total wellness for days 1 and 2 postarrival compared with travel with <6 time zones (P < .05). Additionally, fatigue, sleep, and total scores were worse on day 2 following trips of 9+ time zones. Eastward travel resulted in poorer sleep ratings (ß = 0.52, P < .001) than westward travel within time zone groupings. CONCLUSIONS: Perceptual ratings of fatigue and sleep become progressively worse as travel increases in national-team soccer players, especially after travel across 9+ time zones and eastward travel.

Effects of long-haul transmeridian travel on physiological, sleep, perceptual and mood markers in Olympic team support staff.

The objective of this study was to holistically examine the impact of long-haul transmeridian travel (LHTT) on perceptual, mood, sleep and physiological markers in Olympic team support staff travelling to Japan for the 2020 Summer Olympic Games. An observational descriptive study design was used. Nine support staff members of the Irish Olympic team (2 M/7 F; age 34.3 ± 8.3 y (mean ±SD)) embarked on a long-haul (LH) eastward flight across eight time-zones from Ireland to Japan (approx. 24 h total travel time), to work at the Irish Team's 2020 Summer pre-Olympic Games camp, postponed to July 2021 due to Covid-19 pandemic. Perceived jet lag and travel fatigue symptoms, mood states and salivary markers for circadian rhythm and stress were assessed in the morning and evening during the week prior to travel as baseline (BL) measures and on days 1 to 8 (C1-C8) and day 15 (C15) post-travel. Night-time sleep (duration and quality) was monitored via actigraphy monitors and self-report sleep diaries. Participants perceived themselves to be significantly jet lagged for six days post-travel (p < .05). Morning sCort decreased by 66% on C1 and remained significantly lower than BL until C6 (p ≤ .03). On arrival participants perceived sleep to be worse than BL on arrival (C1, C2, C4, C5; p ≤ .04), with significantly shorter sleep duration (C2, C3, C6; p ≤ .01) and lower sleep efficiency (C2, C6; p ≤ .04) recorded by actigraphy, all normalizing by C7. Negative changes in mood states were evident in the evening time following LHTT, with significant elevations in confusion (C2, C3, p ≤ .02), fatigue (C2, C3; p ≤ .03) and depression (C3, C7; p < .05) and reduction in vigour (C2, C6, C7; p < .05). Following LHTT in an eastward direction across eight time-zones, it took seven days for perceived jet lag, physiological markers for circadian rhythm and sleep to normalize in Olympic team support staff. Despite alleviation of jet lag and fatigue and return of sleep to normal by C15, vigor remained low, indicating a "submerged" mood profile in these Olympic team support staff. These findings highlight the need to put strategies in place before and after LHTT for the Olympic Games to assist Olympic team support staff to maximize sleep, minimize stress and assist with expediating recovery from jet lag and travel fatigue, allowing them to perform optimally in supporting Olympic athletes in their final preparations for the Games.

Travelers' perceptions of jetlag and travel fatigue: A scoping review.

Effective management strategies for jetlag have largely been studied and evaluated through the lens of circadian science and biological rhythms. Jetlag is mostly self-managed by the individual. The most effective strategies require individuals to make behavioral changes to carefully alter sleep-wake schedules and time light exposure. However, travelers' perceptions, including their experiences, beliefs about jetlag/travel fatigue, and management expectations remain unclear. Therefore, the aim of this scoping review was to systematically synthesize the literature to understand what is currently known about travelers' perceptions of jetlag and travel fatigue. A literature search was conducted through EMBASE, PsycINFO, PubMed and Scopus generating 1164 results (2 articles known to authors), which were screened against our inclusion criteria. Twenty-two studies including data from 3952 participants were evaluated for its study design and traveler-centered outcome measures across the domains of: 1) Traveler Health Beliefs and Knowledge about Jetlag and Travel Fatigue; 2) Experience of Jetlag and Travel Fatigue 3) Traveler Priorities; 4) Self-reported Management Strategies for Jetlag and Travel Fatigue; and 5) User Experiences of Management Strategies. Synthesis of results suggests a potential mismatch between researchers' focus on circadian misalignment and travelers' focus on air travel comfort. A better understanding of the beliefs, attitudes, knowledge, satisfaction, experiences, and expectations about jetlag and travel fatigue will better enable the development of interventions that align with traveler priorities.

The effects of travel on performance: a 13-year analysis of the National Rugby League (NRL) competition.

The purpose was to investigate the effects of travel on performance in the National Rugby League (NRL). A total of 4,704 observations from 2,352 NRL matches (2007-2019) were analysed. The effect of travel on match outcome (i.e., win/loss) was analysed using a generalized linear mixed model, and the points difference using a linear mixed model. For every 1,000 km travelled in the NRL, the estimated probability of winning a match was reduced by -2.7% [-5.7 to 0.3%] and the estimated points difference by -1.1 [-2.0 to -0.2] points. In relation to every 1,000 km travelled, the 2007-2009 seasons had the greatest reduction in the likelihood of winning a match (-2.7% [-4.7 to -0.6%]), with the 2018-2019 seasons having the greatest likelihood (1.1% [-1.2 to 3.3%]). Regarding inter-state travel, teams from the state of Queensland had the greatest reduction in the likelihood of winning a match while the team from the state of Victoria had the greatest likelihood, although there were no clear differences between states. These data suggest that travel has impacted performance in NRL matches although this effect has reduced over time. These findings are useful for practitioners that prepare athletes in sports where frequent short-haul travel is required.

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.

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.

Covid-19 Has Turned Home Advantage Into Home Disadvantage in the German Soccer Bundesliga.

The main factors for home advantage (HA), quantified by the number of points won at home expressed as a percentage of all points, are believed to be crowd support, territoriality, familiarity, and travel fatigue. In 2020, the German Soccer Bundesliga interrupted its championship due to the Covid-19 pandemic after 25 rounds and the last nine rounds were played without audience. This unique situation allowed studying the effect of spectators on the team's performance and the referee's decisions. We hypothesized a decrease in HA and a more balanced distribution of fouls and disciplinary cards in the games without audience (GWOA) compared to the games with audience (GWA). We evaluated n = 223 GWA and n = 83 GWOA of the season 2019/20 and all games of the preceding season 2018/19 to analyze the distribution of game outcomes (wins, losses, and draws) and HA. We analyzed the number of fouls, disciplinary cards, and penalty kicks. We found significant differences in HA between GWA (HA = 54.35%) and GWOA (HA = 44.1%) as well as GWOA and games of 2018/19 (HA = 57.63%). The distribution of game outcomes in GWOA did not differ from GWA but differed significantly from 2018/19 (p = 0.031). The distribution of fouls showed a significant difference to equal distribution in GWA [home: 2,595 (48.56%); away: 2,749 (51.44%)] but not in GWOA [home: 1,067 (50.54%); away: 1,044 (49.46%)]. In the GWOA, we counted 178 (51.1%, home) and 170 (48.9%, away) cards, representing a significant difference in the distribution to GWA [home: 405 (44.85%); away: 498 (55.15%)]. The number of red cards differed significantly from an equal distribution for GWA (14 home and 28 away) but not for GWOA (eight home and seven away). In the last nine rounds without audience, we observed more home losses (36) than home wins (27). Hence, the Covid-19 lock-down led to a home disadvantage. One reason for this surprising result could be that the home team is missing an important familiar aspect when playing in their empty stadium without social support from their home audience. Furthermore, both teams know about the HA thus the away team could be more motivated in this unusual situation.

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.

What works for jetlag? A systematic review of non-pharmacological interventions.

Jetlag is a combination of travel fatigue and circadian misalignment resulting from air travel across time zones. Routinely recommended interventions based on circadian science include timely exposure to light and darkness (scheduled sleep), but the real-world effectiveness of these and other non-circadian strategies is unknown. We systematically reviewed the evidence for non-pharmacological interventions for jetlag. PubMed, EMBASE, Scopus, and Web of Science were searched. Studies reviewed 1) involved human participants undergoing air travel with a corresponding shift in the external light-dark cycle; 2) administered a non-pharmacological intervention; 3) had a control or comparison group; and 4) examined outcomes such as jetlag symptoms, sleep, cognitive/physical performance, mood, fatigue, or circadian markers. Thirteen studies used light exposure, physical activity, diet, chiropractic treatment, or a multifaceted intervention to counteract jetlag. Nine studies found no significant change in the outcomes, three reported mixed findings, and one was positive. The null findings are likely due to poorly designed circadian interventions and neglect of contributors to travel fatigue. Higher quality studies that schedule darkness as well as light, in the periods before, during, and after flight are needed to reduce the circadian component of jetlag. Interventions should also address the stressors that contribute to travel fatigue.

Effects of simulated domestic and international air travel on sleep, performance, and recovery for team sports.

The present study examined effects of simulated air travel on physical performance. In a randomized crossover design, 10 physically active males completed a simulated 5-h domestic flight (DOM), 24-h simulated international travel (INT), and a control trial (CON). The mild hypoxia, seating arrangements, and activity levels typically encountered during air travel were simulated in a normobaric, hypoxic altitude room. Physical performance was assessed in the afternoon of the day before (D - 1 PM) and in the morning (D + 1 AM) and afternoon (D + 1 PM) of the day following each trial. Mood states and physiological and perceptual responses to exercise were also examined at these time points, while sleep quantity and quality were monitored throughout each condition. Sleep quantity and quality were significantly reduced during INT compared with CON and DOM (P < 0.01). Yo-Yo Intermittent Recovery level 1 test performance was significantly reduced at D + 1 PM following INT compared with CON and DOM (P < 0.01), where performance remained unchanged (P > 0.05). Compared with baseline, physiological and perceptual responses to exercise, and mood states were exacerbated following the INT trial (P < 0.05). Attenuated intermittent-sprint performance following simulated international air travel may be due to sleep disruption during travel and the subsequent exacerbated physiological and perceptual markers of fatigue.