Editorial: The Reciprocal Relationship Between Sleep and Stress in Elite Athletes

Modern elite athletes are facing more mental, emotional and social demands than ever before, including, amongst others, pressure on personal relationships, media demands, sponsor needs and public interest (Walsh et al., 2021). The majority of elite athletes sleep less than the recommended night-time sleep duration of 7–9 h per night and obtain less than their self-assessed sleep need (Sargent et al., 2021). Many endogenous and environmental factors are able to negatively influence sleep duration and quality in athletes, including evening high-intensity training, pre-competition anxiety, mental fatigue or long-haul travel (Aloulou et al., 2021; Janse van Rensburg et al., 2021; Walsh et al., 2021). Unfortunately, poor sleep can have negative effects on both psychological and physiological aspects which can ultimately lead to an impairment of physical and mental performance (Fullagar et al., 2015; Filipas et al., 2021; Vitale et al., 2021). Thus, it was the aim of this Research Topic to explore the reciprocal relationship between sleep and stress, and to provide insights into potential contributions regarding athletic performance and health

Injury risk factors, screening tests and preventative strategies: A systematic review of the evidence that underpins the perceptions and practices of 44 football (soccer) teams from various premier leagues

Purpose: To systematically review the scientific level of evidence for the ‘Top 3’ risk factors, screening tests and preventative exercises identified by a previously published survey of 44 premier league football (soccer) teams. Also, to provide an overall scientific level of evidence and graded recommendation based on the current research literature. Methods: A systematic literature search (Pubmed [MEDLINE], SportDiscus, PEDRO and Cochrane databases). The quality of the articles was assessed and a level of evidence (1++ to 4) was assigned. Level 1++ corresponded to the highest level of evidence available and 4, the lowest. A graded recommendation (A: strong, B: moderate, C: weak, D: insufficient evidence to assign a specific recommendation) for use in the practical setting was given. Results: Fourteen studies were analysed. The overall level of evidence for the risk factors previous injury, fatigue and muscle imbalance were 2++, 4 and ‘inconclusive’, respectively. The graded recommendation for functional movement screen, psychological questionnaire and isokinetic muscle testing were all ‘D’. Hamstring eccentric had a weak graded ‘C’ recommendation, and eccentric exercise for other body parts was ‘D’. Balance/proprioception exercise to reduce ankle and knee sprain injury was assigned a graded recommendation ‘D’. Conclusions: The majority of perceptions and practices of premier league teams have a low level of evidence and low graded recommendation. This does not imply that these perceptions and practices are not important or not valid, as it may simply be that they are yet to be sufficiently validated or refuted by research

Monitoring of post-match fatigue in professional soccer: Welcome to the real world

Participation in soccer match-play leads to acute and transient subjective, biochemical, metabolic and physical disturbances in players over subsequent hours and days. Inadequate time for rest and regeneration between matches can expose players to the risk of training and competing whilst not entirely recovered. In professional soccer, contemporary competitive schedules can require teams to compete in-excess of 60 matches over the course of the season while periods of fixture congestion occur prompting much attention from researchers and practitioners to the monitoring of fatigue and readiness to play. A comprehensive body of research has investigated post-match acute and residual fatigue responses. Yet the relevance of the research for professional soccer contexts is debatable notably in relation to the study populations and designs employed. Monitoring can indeed be invasive, expensive, time-inefficient and difficult to perform routinely and simultaneously in a large squad of regularly competing players. Uncertainty also exists regarding the meaningfulness and interpretation of changes in fatigue response values and their functional relevance, and practical applicability in the field. The real-world need and cost-benefit of monitoring must be carefully weighed up. In relation to professional soccer contexts, this opinion paper intends to: 1) debate the need for PMF monitoring, 2) critique the real-world relevance of the current research literature, 3) discuss the practical burden relating to measurement tools and protocols and the collection, interpretation and application of data in the field, and, 4) propose future research perspectives

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.https://www.springer.com/journal/402792022-07-14hj2021Sports MedicineStatistic

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Football : les stratégies pour une récupération optimale

International audienc

Cinétiques de récupération de la fonction musculaire, des perceptions subjectives et de paramètres biochimiques à lřissue dřun exercice intermittent spécifique au football

International audienceMathieu Nédélec 12, Serge Berthoin 1, Grégory Dupont 11UDSL, EA4488, Université de Lille Nord de France, F-59000 Lille, France 2ENS-CACHAN, Bruz, [email protected] but de cette étude était dřanalyser les cinétiques de récupération de joueurs de football de haut niveau lors des 72h suivant la réalisation dřun exercice intermittent spécifique au football réalisé sur un tapis roulant non motorisé. La performance au squat jump, à un test de répétition de sprints et le pic de force isométrique nřont pas été significativement affectés ni immédiatement après ni au cours des 72h suivant lřexercice. Par contre, les retours aux valeurs initiales des concentrations de créatine kinase et dřacide urique ainsi que des douleurs musculaires étaient plus rapides que celles reportées à lřissue dřun match de football. En plus des courses réalisées au cours dřun match de football, dřautres facteurs tels que les dommages musculaires et/ou la fatigue cognitive pourraient contribuer à la fatigue induite par le match. Mots clés : sports collectifs, performance, fatigueINTRODUCTIONDans le football de haut niveau professionnel, le nombre de rencontres se multiplie. Lorsque le calendrier est surchargé, les joueurs jouent 2 matches par semaine durant plusieurs semaines consécutives, ce qui pourrait générer blessure et/ou contreperformance (Ekstrand et al., 2004; Dupont et al., 2010). La variabilité de la distance parcourue à haute intensité au cours de matches de football est importante puisque les coefficients de variation intra- individuels varient de 36.0% à 52.1% (Dupont et al., 2010). Le but de cette étude était dřanalyser les cinétiques de récupération de la fonction musculaire, des perceptions subjectives et de paramètres biochimiques lors des 72h suivant un exercice intermittent de 90min basé sur le profil dřactivité de matches de football de haut niveau.MÉTHODESHuit footballeurs professionnels ont réalisé un exercice standardisé de 90min sur un tapis roulant non motorisé (Woodway Force 3.0, USA). Cet exercice a été élaboré à partir de données physiques issues de joueurs de football professionnel de haut niveau (Rampinini et al. 2007). La performance au squat jump (SJ), au saut avec contremouvement (CMJ), à un test de répétition de sprints (RS), le pic de force isométrique (picFI), les perceptions subjectives (fatigue, douleurs musculaires, stress perçu), les concentrations de créatine kinase ([CK]) et dřacide urique ([AU]) ont été recueillis avant, immédiatement après, 24, 48 et 72h après lřexercice de 90min.RÉSULTATS ET DISCUSSIONDes augmentations significatives de [CK] (p<0.01), de [AU] (p<0.01) et des perceptions subjectives (p<0.05) ainsi quřune diminution significative de la performance au CMJ (p<0.01) ont été observées immédiatement après lřexercice de 90min. La masse corporelle à lřissue de lřexercice était significativement inférieure (p<0.001) à celle mesurée avant lřexercice, avec une diminution de -1.4±0.3 kg (-1.8±0.3%). La consommation hydrique (boisson contenant 6.4% de glucides) au cours du test était de 472±150 ml. La perte hydrique estimée était de 1884±289 ml. Les [AU] retournaient à leurs valeurs initiales 24h après lřexercice tandis que les [CK] et les douleurs musculaires retournaient à leurs valeurs initiales 48h après lřexercice. La performance au CMJ était toujours significativement (p<0.01) réduite 72h après lřexercice. Les performances au SJ, aux tests de RS et au picFI nřont pas été significativement affectées ni immédiatement après, ni au cours des 72h suivant lřexercice de 90min. Les cinétiques de récupération différentes entre CMJ et SJ confirment que la performance aux activités musculaires dřétirement-contraction se normalise plus lentement que la performance aux activités musculaires concentriques (Horita et al., 2003).363CONCLUSIONLes normalisations des [CK], des [AU] et des douleurs musculaires dans cette étude sont plus rapides que celles reportées à lřissue dřun match de football (Ispirlidis et al., 2008). En plus des courses réalisées au cours dřun match de football, les activités générant des dommages musculaires et/ou de la fatigue cognitive, limitées lors de lřexercice intermittent de 90min, pourraient contribuer à la fatigue induite par le match.BIBLIOGRAPHIEDupont, G., Nedelec, M., McCall, A., McCormack, D., Berthoin, S., Wisløff, U. (2010). Effect of 2 soccer matches in a week on physical performance and injury rate. American Journal of Sports Medicine, 38(9), 1752-1758.Ekstrand, J., Waldén, M., Hägglund, M. (2004). A congested football calendar and the wellbeing of players: correlation between match exposure of European footballers before the World Cup 2002 and their injuries and performances during that World Cup. British Journal of Sports Medicine, 38, 493-497.Horita, T., Komi, P.V., Hämäläinen, I., Avela, J. (2003). Exhausting stretch-shortening cycle (SSC) exercise causes greater impairment in SSC performance than in pure concentric performance. European Journal of Applied Physiology, 88(6), 527-534.Ispirlidis, I., Fatouros, I.G., Jamurtas, A.Z., Nikolaidis, M.G., Michailidis, I., Douroudos, I., Margonis, K., Chatzinikolaou, A., Kalistratos, E., Katrabasas, I., Alexiou, V., Taxildaris, K. (2008). Time-course of changes in inflammatory and performance responses following a soccer game. Clinical Journal of Sport Medicine, 18(5), 423-431.Rampinini, E., Coutts, A.J., Castagna, C., Sassi, R., Impellizzeri, F.M. (2007). Variation in top level soccer match performance. International Journal of Sports Medicine, 28(12), 1018-1024

Technologies, recherche et développement : du labo au terrain...

National audienc

Reproductibilité de la performance lors d’un test de répétition de sprints

International audienceIntroduction. — The aim of this study is to check the reliability of performance during a repeatedsprint test.Summary of facts. — Eleven amateur soccer players (30.3±6.0 years old) volunteered for thestudy. All subjects completed two tests separated by 1 week. The test consisted in 6×6 secondsprints repeated at 20-second intervals on a non-motorized treadmill. Intraclass correlation coefficients (ICC), typical error of measurement (TEM) and coefficients of variation (CV) werecalculated for peak power output during 6-second sprint, mean power output during test andpercentage decrement score. The ICC, TEM and CV for peak power output are 0.91, 91 W,and 4.1%, respectively. The ICC, TEM and CV for mean power output are 0.99, 27 W and 1.4%,respectively. The ICC, TEM and CV for percentage decrement score are 0.65, 3.3% and 32.1%,respectively.Conclusion. — Peak power output during 6-second sprint and mean power output during testshow good test-retest reliability, but the reliability of the percentage decrement score is poor.Introduction. —Cette étude a pour objectif de vérifier la reproductibilité de la performancelors d’un test de répétition de sprints.Synthèse des faits. —Onze footballeurs amateurs (30,3± 6,0 ans) ont participé à cette étude.Les sujets ont réalisé deux fois, à une semaine d’intervalle, un test de répétition de six sprintsde 6 secondes entrecoupés de 20 secondes de récupération passive sur un tapis roulant nonmotorisé. Le coefficient de corrélation intraclasse (CCI), l’erreur-type (ET) et le coefficientde variation (CV) du pic de puissance développée sur un sprint de 6 secondes, de la puissancemoyenne développée au cours du test et d’un indice de diminution de performance ont étécalculés. Les CCI, ET et CV du pic de puissance sont respectivement de 0,91, de 91 W et de4,1 %. Les CCI, ET et CV de la puissance moyenne sont respectivement de 0,99, de 27 W et de1,4 %. Les CCI, ET et CV de l’indice de diminution de performance sont respectivement de 0,65,de 3,3 % et de 32,1 %.Conclusion. — Ces résultats montrent que la reproductibilité du pic de puissance et de la puissancemoyenne développée au cours du test sont bonnes, mais que la reproductibilité de l’indicede diminution de performance est faible

Recovery after an Intermittent Test

International audienc