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International audience; When implementing computer vision algorithms, the quality of the video input is a crucial parameter for systematic application as :• Training and inference conditions of Deep Learning models may differ.• Video quality may be downgraded due to sourcing or transfer encoding.• Storage capacity may limit the volume/quantity of data available.To better understand the sensitivity of inference with regarding video quality, we investigated the effect of video compression on the output of a human pose estimation network model.

Background Breast cancer (BC) has particular characteristics in young women, with diagnosis at more advanced stages, a poorer prognosis and highly aggressive tumors. In NeoFit, we will use an activity tracker to identify and describe various digital profiles (heart rate, physical activity, and sleep patterns) in women below the age of 45 years on neoadjuvant chemotherapy for BC. Methods NeoFit is a prospective, national, multicenter, single-arm open-label study. It will include 300 women below the age of 45 years treated with neoadjuvant chemotherapy for BC. Participants will be asked to wear a Withing Steel HR activity tracker round the clock for 12 months. The principal assessments will be performed at baseline, at the end of neoadjuvant chemotherapy and at 12 months. We will evaluate clinical parameters, such as toxicity and the efficacy of chemotherapy, together with quality of life, fatigue, and parameters relating to lifestyle and physical activity. The women will complete REDCap form questionnaires via a secure internet link. Discussion In this study, the use of an activity tracker will enable us to visualize changes in the lifestyle of young women on neoadjuvant chemotherapy for BC, over the course of a one-year period. This exploratory study will provide crucial insight into the digital phenotypes of young BC patients on neoadjuvant chemotherapy and the relationship between these phenotypes and the toxicity and efficacy of treatment. This trial will pave the way for interventional studies involving sleep and physical activity interventions. Trial registration Clinicaltrials.gov identifier: NCT05011721. Registration date: 18/08/2021.

International audience; The objective was to compare the metabolic responses of high-level national swimmers to threshold or polarised training. 22 swimmers (n = 12 males and 10 females) participated in a 28-week cross-over intervention study consisting of 2 × 6 period weeks of training. Swimmers were assigned randomly to either training group for the first period: polarised (POL) (81% in energetic zone 1: blood lactate [La]b ≤ 2 mmol.L-1; 4% in zone 2: 2 mmol.L-1 4 mmol.L-1) or threshold (THR) (65%/25%/10%). Before and after each training period, urine samples were collected for non-targeted metabolomics analysis. Mixed model analysis was performed on metabolomics data including fatigue class factors and/or training and/or interaction. Ion intensities of 6-keto-decanoylcarnitine (+31%), pregnanediol-3-glucuronide (+81%), P-cresol sulphate (+18%) were higher in the threshold group (P

Background: The French National Observatory for Physical Activity and Sedentary Behaviors conducted a national survey aiming to evaluate the potential effects of confinement on the population’s physical activity levels and sedentary behaviors. Methods: In close collaboration with the French Ministry of Sports and a selected expert committee, 3 different questionnaires investigating 3 subgroup populations were included in the survey: (1) children, (2) adolescents, and (3) adults. Results: Forty-two percentage of children, 58.7% of adolescents, 36.4% of adults, and 39.2% of older people had reduced physical activity levels. Particularly, active transportation and endurance practices showed a significant decrease, while domestic, muscular strengthening, and flexibility activities increased. Sitting time and screen time increased, respectively, in 36.3% and 62.0% of children, 25.5% and 69.0% in adolescents, 24.6% and 41.0% in adults, and 36.1% and 32.1% in seniors. Conclusion: The COVID-19 confinement period led to important modifications in individual movement behaviors at all ages, particularly favoring decreased physical activity and increased sedentariness. These findings suggest that the authors need to inform and encourage people to maintain and improve their physical activities and to change their sedentary time habits during postconfinement and during the period of a potential future lockdown.

International audience; International elite Para swimmers form a large portion of the overall multi-medalist winning population. For the highest performing Para swimmers, world class performances were achieved across different strokes. The aim of this study was to quantify the level of involvement across different events and to examine this in relation to the level of performance. The performances in swimming speed of the top 100 females and males for both Para- and non-disabled swimmers were collected in 11 race events between 2009 and 2019 (4,400 performances for 307 Para females and 365 Para males, 605 non-disabled females, and 715 non-disabled males). We tallied the number of events in which each swimmer was involved. Swimmers were grouped according to the total number of race events in which they participated. Then the association between involvement and level of performance was investigated. Para swimmers with impairment from classes seven to 14 were involved in a range of race events across different strokes. The most common combination for both Para and non-disabled athletes was over similarly distanced races of the same stroke (50 and 100 m freestyle). The more race events in which Para swimmers involved, the higher the level of performance that was achieved. This trend can partially be explained by the less concentrated competition pool for Para swimmers compared to able-bodied swimmers. Para swimmers with minimal and no physical impairment perform in multiple race events more often than able-bodied swimmers. Fewer Para swimmers at the international level and a less concentrated competition pool could explain these differences.

International audience; PurposeThe aim of the present study was to investigate (i) how glycolytic metabolism assessed by accumulated oxygen deficit (AODgly) and blood metabolic responses (lactate and pH) resulting from high-intensity exercise change during growth, and (ii) how lean body mass (LBM) influences AODgly and its relationship with blood markers.MethodsThirty-six 11- to 17-year olds performed a 60-s all-out test on a rowing ergometer. Allometric modelling was used to investigate the influence of LBM and LBM + maturity offset (MO) on AODgly and its relationship with the extreme post-exercise blood values of lactate ([La]max) and pH (pHmin) obtained during the recovery period.ResultsAODgly and [La]max increased while pHmin decreased linearly with LBM and MO (r2 = 0.46 to 0.72, p

Olympic distance cross-country cycling (XCO) is a discipline subject to wide performance variability due to uncontrollable environmental factors such as altitude, ambient temperature and/or humidity. This study therefore aimed to investigate the impact of environmental factors on XCO performance in under-23 and elite female and male categories. Individual data were collected from Continental Cup, World Cup, World Championship, and Olympics Games for U23 and elite female and male categories from 2009 to 2018. Factors included were race time (range: 55–157 min), average speed (range: 7.6–32.2 km/h), distance (range: 15.2–48.4 km), altitude (range: 50–2680 m), ambient temperature (range 7–41°C), relative and absolute humidity (range: 8–97% and 2.4–25.3 g/m(3), respectively), and categories. The analysis represents 10,966 individual data which indicate a continuous progression of the performance for all categories. Principal component analysis reveals that the slowest XCO performance was resulting from high ambient temperature and absolute humidity. Regressions revealed that only altitude (P

International audience; PURPOSE:Previous studies have noted consequences of ultra-distance trail running on health, but few studies are available regarding the temporal variations of renal biomarker injury during the running. The aim of this study was to assess the of kidney function parameters temporal variation during and on short-term after an ultra-distance race.METHODS:We performed an observational study with 47 subjects participating in an ultra-distance race (80 km). Urine (47 subjects) and blood (21 subjects) samples were serially collected before (baseline-km 0), during (21 and 53 km), on arrival (80 km), and 9 days after the race (d9).RESULTS:Mean serum creatinine increased during the race from 90±14 μmol/L (km0) to 136±32 μmol/L (km 80-p0.05). On day 9, no significant difference remains in blood and urine biomarkers compared to their respective baseline levels.CONCLUSIONS:During an ultra-distance race, despite an acute and transient increase in the serum creatinine levels, urinary biomarkers of AKI displayed only limited changes with a complete regression on day 9. These results suggest the absence of the short-term impact of an ultra-distance race kidney function.

International audience

Background: Judo is a full-contact fighting sport that may lead to severe injuries. There are limited data available on the incidence of judo-related injuries. The French Judo Federation has established a surveillance system to document the frequency and type of injuries during judo competitions. Purpose: To describe the incidence rates and types of judo-related traumatic injuries during 21 seasons of competitions in France with respect to athlete (judoka) age, sex, and level of performance. Study Design: Descriptive epidemiology study. Methods: Between 1993 and 2014, each physician in charge of each judo competition filled out a form in which he/she documented the number of competing judokas, the number of fights, the number of medical interventions, the specific type of traumatic injuries for each intervention, the number of fight interruptions, and the number of athletes removed from the competition venue because of an injury. The age, sex, and level of performance of each judoka were also documented. Variance analysis was applied to assess whether differences in incidence rates of injuries between groups were significant (Student t test and chi-square test). Results: Surveillance of 421,670 fights demonstrated 3511 injuries in 316,203 judokas (incidence proportion, 1.1%). Among the injuries recorded, the most common were sprains (54.3%), fractures (15.6%), and dislocations (12.5%). Female athletes exhibited significantly higher incidence rates for knee sprains and elbow dislocations, whereas male athletes exhibited a higher incidence rate for shoulder dislocations ( P < .001 for all). Regarding age, higher incidence rates were observed in young adults (aged 18-20 years) for acromioclavicular sprains and in children (aged 10-14 years) for clavicle fractures compared with adults (aged 21-35 years) ( P < .001 for both). Both young adult and adult athletes had a higher incidence rate of shoulder dislocations ( P < .001). Regarding the level of performance, athletes competing at higher levels had a higher incidence rate of sprains to the knee ( P < .001). Conclusion: During 21 years of surveillance of injuries in judo competitions in France, the incidence proportion of injuries was 1.1%. Significant differences in incidence rates demonstrated when considering age, sex, and level of performance may help in developing strategies to prevent traumatic injuries in the future.

International audience; Physical exercise has important effects as secondary prevention or intervention against several diseases. Endurance exercise induces local and global effects, resulting in skeletal muscle adaptations to aerobic activity and contributes to an amelioration of muscle performance. Furthermore, it prevents muscle loss. Serum response factor (Srf) is a transcription factor of pivotal importance for muscle tissues and animal models of Srf genetic deletion/over-expression are widely used to study Srf role in muscle homeostasis, physiology and pathology. A global characterisation of exercise adaptation in the absence of Srf has not been reported. We measured body composition, muscle force, running speed, energy expenditure and metabolism in WT and inducible skeletal muscle-specific Srf KO mice, following three weeks of voluntary exercise by wheel running. We found a major improvement in the aerobic capacity and muscle function in WT mice following exercise, as expected, and no major differences were observed in Srf KO mice as compared to WT mice, following exercise. Taken together, these observations suggest that Srf is not required for an early (within 3 weeks) adaptation to spontaneous exercise and that Srf KO mice behave similarly to the WT in terms of spontaneous physical activity and the resulting adaptive responses. Therefore, Srf KO mice can be used in functional muscle studies, without the results being affected by the lack of Srf. Since lack of Srf induces premature sarcopenia, our observations suggest that the modifications due to the absence of Srf take time to occur and that young, Srf KO mice behave similarly to WT in aerobic physical activities.

Background: This study investigated the periodization of elite swimmers' training over the 25 weeks preceding the major competition of the season. Methods: We conducted a retrospective observational study of elite male (n = 60) and female (n = 67) swimmers (46 sprint, 81 middle-distance) over 20 competitive seasons (1992-2012). The following variables were monitored: training corresponding to blood lactate 4-6 mmol.L-1, >6 mmol.L-1, and maximal swimming speed; general conditioning and maximal strength training hours; total training load (TTL); and the mean normalized volumes for both in-water and dryland workouts. Latent class mixed modeling was used to identify various TTL pattern groups. The associations between pattern groups and sex, age, competition event, Olympic quadrennial year, training contents, and relative performance were quantified. Results: For the entire cohort, similar to 86-90% of the training was swum at an intensity of [La](b) 4-6 mmol.L-1, and 3.5-4.5% at > 6 mmol.L-1. Three sprint TTL patterns were identified: a pattern with two long similar to 14-15-week macrocycles, one with two similar to 12-13 week macrocycles each composed of a balanced training load, and one with a single stable flat macrocycle. The long pattern elicited the fastest performances and was most prevalent in Olympic quadrennials (i.e., 4 seasons preceding the 2004, 2008, and 2012 Olympic Games). This pattern exhibited moderate week-to-week TTL variability (6 +/- 3%), progressive training load increases between macrocycles, and more training at 6 mmol.L-1. This fastest sprint pattern showed a waveform in the second macrocycle consisting of two progressive load peaks 10-11 and 4-6 weeks before competition. The stable flat pattern was the slowest and showed low TTL variability (4 +/- 3%), training load decreases between macrocycles (P < 0.01), and more training at 4-6 mmol.L-1 (P < 0.01). Conclusion: Progressive increases in training load, macrocycles lasting about 14-15 weeks, and substantial volume of training at intensities 6 mmol.L-1, were associated with peak performance in elite swimmers. This research was partially funded by the French Institute of Sport, Expertise and Performance (INSEP) and the French Ministry in charge of sports under grant no. 14r21.

International audience; Purpose: To quantify the impact of a polarized distribution of training intensity on performance and fatigue in elite swimmers.Methods: Twenty-two elite junior swimmers (12 males, age = 17 [3] y, and 10 females, age = 17 [3] y) participated in a crossover intervention study over 28 wk involving 2- × 6-wk training periods separated by 6 wk. Swimmers were randomly assigned to a training group for the first period: polarized (81% in zone 1, blood lactate concentration, [La]b ≤ 2 mmol·L−1; 4% in zone 2, 2 mmol·L−1 4 mmol·L−1) or threshold (65%/25%/10%). Before and after each period, they performed a 100-m maximal swimming test to determine performance, maximal [La]b, and oxygen consumption and an incremental swimming test to determine speed corresponding to [La]b = 4 mmol·L−1 (V4 mmol·L−1). Self-reported indices of well-being were collected with a daily questionnaire.Results: Polarized training elicited small to moderately greater improvement than threshold training on 100-m performance (within-group change ± 90% confidence interval: 0.97% ± 1.02% vs 0.09% ± 0.94%, respectively) with less fatigue and better quality of recovery. There was no substantial gender effect. No clear differences were observed in physiological adaptations between groups.Conclusions: In elite junior swimmers, a 6-wk period of polarized training induced small improvements in 100-m time-trial performance and, in combination with less perceived fatigue, forms a viable option for coaches preparing such cohorts of swimmers for competition.

Data has massively invaded the world of high-level sport. Team sports such as football and rugby union, which are among the most publicized sports, are particularly concerned by this phenomenon. In addition, performance in a team sport is multifactorial and multidimensional and are deeply linked to the injuries. Sports scientists seek to understand and contextualize these performances as well as possible. To do so, a lot of data are needed and consumed. Those data are coming from many sources as they are the results of a global thinking between staff members surrounding the athletes. The participation of all the staff, and players, makes sports science answering the call of interdisciplinary research. In this context, biostatistics naturally find their place in direct collaboration with sports scientist, at the interface between data produced and the issues raised by the staff in order to help decision-making.Team sports involve individuals who play as a team. By definition, analyzing these sports requires both individual and collective assessment. It is this double analysis that was carried out during this thesis. The individualization of performance monitoring and health condition of players is clearly essential and it involves the development of statistical tools adapted to the issues raised. Z-score-based methods development for the analysis of biomarkers derived from longitudinal monitoring is an example of the reciprocal contribution that a collaboration between biostatistics and sports science can produce: a better understanding of players' state of health, which is essential for optimizing their performance and minimizing exposure to injury risk factors, and the prospects for optimizing existing statistical tools. The correction of a widely used test, the Mann-Whitney test also finds its place in the will to compare individual performance evolving over time, an issue encountered in detection, selection or rehabilitation protocols.Then, the collective dimension has been investigated. The individualization of the monitoring makes it possible to understand what is happening within each player and to personalize support by the staff. But what about team management? How can managing a group optimize its performance and impact the occurrence of injuries? Through two studies on rugby union, we have shown through the application of adapted statistical tools that the collective dimension of the analysis of the performance was essential to its understanding. Indeed, an optimized group management, favorable to the creation of collective experience, cohesion, and cleverly spreading playing time between the players contributes to better performance. The perspectives raised by these quantitative analyzes of collective experience in a collective sport were discussed. Including the impact on the occurrence of injuries which is a major issue raised by staffs because directly impacting the performance of the group. But the relationship between workforce management and injuries is poorly analyzed.Studies presented in this thesis illustrate some stapes of the necessary exchange between the different disciplines gathered around sports sciences and show how biostatistics fit into the decision-making process of the staffs., Les données ont massivement investi le monde du sport de haut niveau. Les sports collectifs comme le football et le rugby à 15 qui sont parmi les sports les plus médiatisés sont particulièrement concernés par ce phénomène. De plus, les performances dans un sport collectif sont multifactorielles et multidimensionnelles et sont étroitement liées à la survenue de blessures. Les sport scientists cherchent à comprendre et à contextualiser au mieux ces performances. Pour se faire, ils demandent et consomment énormément de données dont les sources sont multiples car émanant de la concertation des différents membres du staff entourant les athlètes. La participation de l’ensemble du staff, et des joueurs, fait des sciences du sport une thématique de recherche pluridisciplinaire. Dans ce contexte, les biostatistiques trouvent naturellement leur place en collaboration directe avec les sport scientitsts, à l’interface entre les données produites et les problématiques posées par le staff afin d’aider à la prise de décision.Les sports collectifs impliquent des individus qui jouent en équipe. Par définition, analyser ces sports nécessite un regard à la fois individuel et collectif. C’est cette double analyse qui a été réalisée au cours de cette thèse. L’individualisation du suivi des performances et de l’état de santé des joueurs est clairement indispensable et il implique l’élaboration d’outils statistiques adaptés aux problématiques soulevées. Le développement de méthodes basées sur le z-score pour l’analyse de marqueurs biologiques issus d’un suivi longitudinal est un exemple de l’apport réciproque qu’une collaboration entre biostatistiques et science du sport peut produire : une meilleure compréhension de l’état de santé des joueurs indispensable à l’optimisation de leur performance et à la minimisation de l’exposition aux facteurs de risques de blessure et les perspectives d’optimisation d’outils statistiques existants. La correction d’un test largement utilisé, le test de Mann-Whitney trouve aussi sa place dans la volonté de comparer des performances individuelles évoluant au cours du temps, problématique rencontrée dans la détection, la sélection ou encore les protocoles de soins. C’est ensuite la dimension collective qui a été investiguée. L’individualisation des suivis permet de comprendre ce qu’il se passe au sein de chaque joueur et de personnaliser les prises en charges par le staff. Mais qu’en est-il de la gestion du collectif ? Comment la gestion d’une équipe, d’un groupe peut optimiser sa performance et impacter la survenue de blessures ? A travers deux études sur le rugby à XV, nous avons montré à travers l’application d’outils statistiques adaptés que la dimension collective de l’analyse de la performance était indispensable à sa compréhension. En effet une gestion de groupe optimisée, favorable à la création d’expérience collective, de cohésion, répartissant intelligemment le temps de jeu entre les joueurs participe à la réalisation de meilleures performances. Les perspectives soulevées par ces analyses quantitatives de l’expérience collective dans un sport collectif ont été discutées. Dont l’impact sur la survenue des blessures qui est une problématique majeure soulevée par les staffs car impactant directement la performance du groupe. Mais les relations entre gestion d’effectif et blessures sont à ce jour peu analysées.Les études présentées dans cette thèse illustrent certaines étapes de l’échange nécessaire entre les différentes disciplines rassemblées autour des sciences du sport et montrent comment les biostatistiques s’inscrivent dans le processus de décision des staffs.

1873-6750 Joffin, Nolwenn Noirez, Philippe Antignac, Jean-Philippe Kim, Min-Ji Marchand, Philippe Falabregue, Marion Le Bizec, Bruno Forest, Claude Emond, Claude Barouki, Robert Coumoul, Xavier Journal Article Netherlands Environ Int. 2018 Oct 31. pii: S0160-4120(18)31382-5. doi: 10.1016/j.envint.2018.10.027.; International audience; BackgroundPersistent organic pollutants (POPs) are known to accumulate in adipose tissues (AT). This storage may be beneficial by diverting POPs from other sensitive tissues or detrimental because of chronic release of pollutants as indirectly suggested during weight loss. The aim is to study the biological and/or toxic effects that chronic POP release from previously contaminated grafted AT could exert in a naïve mouse.MethodsC57BL/6J male mice were exposed intraperitoneally to 2,3,7,8-tetrachlorodibenzo-p-doxin (TCDD); their epididymal fat pads were collected and grafted on the back skin of uncontaminated recipient mice whose brain, liver, and epididymal ATs were analyzed (TCDD concentration, relevant gene expression). Kinetics of release and redistribution were modeled using Physiologically Based PharmacoKinetics (PBPK).ResultsThe grafts released TCDD over a period of 10 weeks with different kinetics of distribution in the three organs studied. A PBPK model was used to simulate the AT releasing process and the incorporation of TCDD into the major organs. At three weeks post-graft, we observed significant changes in gene expression in the liver and the host AT with signatures reminiscent of inflammation, gluconeogenesis and fibrosis as compared to the control.ConclusionsThis study confirms that AT-stored TCDD can be released and distributed to the organs of the recipient hence leading to distinct changes in gene expression. This original model provides direct evidence of the potential toxic-relevant effects when endogenous sources of contamination are present.

ISBN : 979-10-97391-03-4; International audience; Les jeux vidéo, par leur double nature de comportement et de fiction (Juul, 2006), nous invitent à questionner qui est l'auteur des récits qu'ils proposent. Bien que le fait de mobiliser la notion d'interactivité comme élément distinctif des jeux vidéo par rapport à d'autres médias soit discutable – Galloway préfère par exemple parler d'active-based medium (2006, p. 3) – il semble malgré tout que leurs créateurs et les joueurs s'attachent particulièrement à considérer cela comme une spécificité de ce médium. De facto, de nombreux éléments et marqueurs présents et directement observables font des jeux vidéo des objets particulièrement intéressants à étudier lorsqu'il s'agit d'observer les relations entre le joueur, l'auteur et leurs créations. Une première lecture de ce dilemme serait alors de penser les game designers comme les véritables créateurs de ces jeux. Ils définissent une structure et attribuent des rôles définis aux joueuses et joueurs. Ces derniers ne sont alors que des rouages d'une mécanique plus ou moins bien huilée. Dans le cadre de cet article, le collectif d'auteurs et autrices signataires prend le parti de considérer l'inverse sans la renier ni la critiquer : les joueurs sont créateurs. La question à laquelle nous allons proposer des éléments de réponse est donc : de quoi sont-ils les autrices et auteurs ? Dans cet article, nous souhaitons faire un pas de côté pour interroger le joueur ou la joueuse non pas comme un lecteur-modèle (Eco, 1985) mais comme un créateur laissant des traces et des documents. Pour cela, nous posons un cadre de discussion sur le joueur représenté soit en tant que rouage mécanique à l'instar d'un opérateur sur une machine, soit en tant qu'acteur d'une performance. Par la suite, nous explorons trois pratiques du jeu vidéo qui nous amènent à constater, à l'intérieur de diverses communautés, des phénomènes de citations, d'attribution de découvertes ou de combinaisons d'actions, etc. Si les joueurs ne sont pas les auteurs d'un récit, il semble que les pratiques de ces communautés leur attribuent ce statut lorsqu'il s'agit de comportements techniques et ludiques.

International audience; Maximal physical performances are powerful and accurate biomarkers in the understanding of age-related changes during the aging process. Previous studies have characterized age-related changes from Caenorhabditis elegans to Homo sapiens. We characterized changes in this pattern for H. sapiens, decade by decade, from 1970 to 2017. Using 286,916 performances related to age from the world's best performances in each age group, we measured the relative change of 10 different running and jumping events for both women and men. We compared the change in sexual dimorphism with age and showed that the gender gap in maximal performance regarding age increases gradually, especially after the age of 50. Between 1970 and 2017, the performances for all age groups in all events have slightly progressed. However, during the last decades, the relative progression of the best performances for all age groups has decreased in both range and frequency, suggesting that age-related maximal physical performances for H. sapiens are reaching their physiological limits.

National audience; Context - In order to help states to develop policies and strategies impacting on all determinants of physical activity, the WHO has set up a policy analysis tool, the HEPA PAT (Health-Enhancing Physical Activity Policy Analysis Tool). This tool allows evaluation of national policies, while considering the complex network of determinants and influencing factors. This article has a double objective: firstly, to present this tool in order to define its specificity and utility in the development of HEPA national policies; secondly, to illustrate its application in the case of France. Methods - The national HEPA policies and projects in France were identified and analysed using the HEPA PAT methodology and quality criteria to highlight the opportunities and to propose recommendations for improvement. Results - HEPA promotion is a recent and fragmented process in France. Development is more intensive at the local level and needs stronger national support and coordination. The main problem seems to be the lack of long-term vision accompanied by a unified national strategy. Implementation is impaired by vaguely defined action plans, very often without any evaluation criteria or sustainable financing methods. Conclusion - The use of HEPA PAT provides a clear and complete overview of the political structure in the field of physical activity promotion. Further analysis of regional policies and projects is recommended to complete this work.; Contexte : Afin d’appuyer les États dans l’élaboration de stratégies et politiques agissant sur l’ensemble des déterminants de la sédentarité et de la pratique de l’activité physique, l’OMS a mis en place un outil d’analyse des politiques, le Health Enhancing Physical Activity Policy Analysis Tool (HEPA PAT) qui permet d’évaluer la qualité des politiques nationales et de prendre en compte le maillage complexe de ces déterminants. Cet article vise un double objectif : d’une part présenter cet outil pour préciser sa nature et son utilité pour la définition des politiques nationales de promotion de l’activité physique et d’autre part offrir une illustration de son application aux politiques françaises.Méthodes : Ayant d’abord identifié les politiques et les projets HEPA au niveau national, nous les avons ensuite analysés sur la base de l’HEPA PAT et de ses 17 critères de qualité, afin d’identifier des opportunités et de proposer des recommandations.Résultats : La promotion de l’activité physique en France est encore un domaine récent et fragmenté. Son développement est plus visible au niveau local mais requiert une coordination nationale. Le problème fondamental semble être le manque d’une vision à long terme et d’une stratégie unifiée l’accompagnant. La mise en œuvre se trouve limitée aussi par des plans d’action insuffisamment définis ou privés de critères d’évaluation et de financements durables.Conclusion : HEPA PAT offre un portrait clair et complet des efforts des États de promotion de l’activité physique. Cependant, seul un travail supplémentaire d’analyse des niveaux régional et local permettra de générer une vision globale des stratégies de promotion de l’activité physique au sein de la population.

National audience

National audience; L'activité physique est bonne pour la santé... et pour la longévité. Mais, aujourd'hui, la sédentarité grandissante liée ànotre mode de vie contrarie ces bénéfices.

Results from France's 2018 Report Card on Physical Activity for Children and Youth

Objectives: Emphasize the importance of setting up training load quantification models in sport.News: Sometimes neglected due to its time-consuming aspect, the quantification of training loads proves to be of great interest nevertheless, including in high performance sport. It is essential to place load quantification at the center of the training program so that it regains its main role within practice.Perspectives: This will have to go through the setting up of mixed models, including external and internal loads. Recent articles have placed internal loads as predominant indicators, which highlight the athlete’s knowledge on how they perceive fatigue, recovery or session intensity. A recent model of loads ratio taking into account the chronic load and the acute load seems extremely relevant. This reflection on acute/chronic ratios needs to be extrapolated to other variables of follow-up and to cross with the monitoring of fatigue and injuries.Conclusion: This model is useful for physical preparation, training monitoring, injury preven- tion and reathletisation in accordance to competitive requirements. Moreover, the computing of the ratio load could be transferable to all sports and all levels., Objectifs: Souligner la nécessité et l'intérêt de la mise en place de modèles de quantification de charge dans le sport de haut niveau. Actualités: Parfois délaissé, y compris dans le sport de haut niveau, notamment par son aspect chronophage, la quantification de la charge d'entraînement revêt pourtant de grands intérêts. Il est essentiel de replacer au centre de la programmation la quantification de la charge afin que la pierre névralgique de tout entraînement retrouve la place qui est la sienne.Perspectives et projets: Ceci devra passer par la mise en place de modèles mixtes, incluant charge externe et interne. De récents articles positionnent les indicateurs de charges internes comme prépondérants et soulignent la bonne connaissance des athlètes sur leur ressenti de niveau de fatigue, récupération ou intensité des séances. Un modèle récent de ratio de charges prenant en compte la charge chronique et la charge actuelle, paraît extrêmement pertinent. Ce positionnement autour de ratios aiguë/chronique est à extrapoler sur d’autres variables de suivi et intéressant à croiser avec du monitoring de la fatigue et des blessures.Conclusion: Ce type de modèle s’avère utile à la préparation physique, au suivi d’entraînement, à la prévention de la blessure, la réathlétisation face aux exigences compétitives. Par ailleurs, le calcul du ratio de charge peut se révéler transférable à tous les sports et tous les niveaux.

En collaboration avec la mission d'Optimisation de la Performance (MOP)

National audience; Actuel entraîneur du pôle France de Strasbourg,l’ancien insepien partage ses observations, ses idéesd’entraînement qui ont permis au plongeon tricolored’exister sur la scène internationale. Autant de pistes pourréfléchir sur le chemin menant au haut niveau en plongeon etailleurs.

Nowadays, resistance training plays an important part in the training programmes of sportsmen, because it can optimise two essential parameters of physical performance: strength and power. Nutritional strategies following exercise can maximise the muscle responses from resistance training. Quality, quantity and timing of protein intake have particularly engaged the attention of scientific studies. While the majority of relevant research has investigated the intake of protein after a single bout of resistance exercise, this particular research project aims to investigate the effect of post-exercice protein intake during several weeks of resistance training.The objectives of this project are 1) to identify the optimal ratio between slow proteins (casein) and fast proteins (whey) of milk, present in a recovery riched-protein drink, on the muscle adaptations from resistance training (muscle mass and strength) and, 2) to investigate the muscle responses to slow protein intake a few hours after resistance training exercise. Results from the first study show that there is no resulting gain in muscle mass when the ratio of fast protein is equal to or higher than that of slow protein, despite an resulting increase in plasma leucine. The second study 1) confirms that ingestion of fast protein after each resistance training session improves muscle mass and strength gains, and 2) suggests that intake of casein 3 hours after the end of each training session can maximise the gain of strength during resistance training. These results allow specific recommendations to be formulated for protein intake during the recovery period after resistance training, both in planning the quality (study 1), quantity (studies 1 and 2) and timing (study 2) of protein intake during resistance training programmes., De nos jours, l’entraînement en musculation occupe une part importante dans la programmation d’entraînement des sportifs car il permet d’optimiser deux paramètres essentiels à la performance, la force et la puissance. Les stratégies nutritionnelles qui accompagnent les séances de musculation sont susceptibles d’influencer les réponses à l’entraînement. Parmi ces stratégies, celle qui a surtout retenu l’attention du monde scientifique concerne les caractéristiques des apports protéiques, et notamment les aspects de quantité, de qualité et du moment d’apport optimaux. Alors que la grande majorité des travaux ont été conduit dans le cadre d’un exercice unique, ce travail de thèse se propose d’évaluer l’intérêt d’un apport protéique en récupération d’exercices programmés dans le cadre d’un entraînement en musculation de plusieurs semaines. Il s’agit de 1) préciser l’impact du rapport entre les protéines lentes (caséines) et les protéines rapides (lactosérum) du lait - présentes dans une boisson protéique de récupération - sur les adaptations musculaires à un entraînement en musculation (masse musculaire et force) et, 2) de vérifier l’intérêt et le moment optimal d’un apport en protéines lentes, à distance de l’entraînement en musculation, sur les réponses musculaires à l’entraînement. Les résultats de la première étude montrent une augmentation significative de la concentration plasmatique en leucine lorsque la proportion de protéines rapides est supérieure ou égale à la proportion de protéines lentes, par rapport à la situation inverse (plus de caséine que de lactosérum). Mais, ceci ne se traduit pas par des gains hypertrophiques supérieurs. La seconde étude, 1) confirme l’intérêt de l’ingestion de protéines rapides après chaque séance pour améliorer le gain de masse musculaire en réponse à l’entraînement en musculation, et 2) suggère l’intérêt d’un apport de caséine 3h après la fin de chaque séance d’entraînement pour maximiser les gains de force pendant l’entraînement en musculation. Ces résultats permettent de préciser les recommandations d’apport en protéines en phase de récupération de séances de musculation, tant au plan de la qualité des apports azotés (étude 1), de leur quantité (études 1 et 2), que du moment d’apport (étude 2).

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International audience; Periodization of swim training in the final training phases prior to competition and its effect on performance have been poorly described. We modeled the relationships between the final 11 weeks of training and competition performance in 138 elite sprint, middle-distance, and long-distance swimmers over 20 competitive seasons. Total training load (TTL), strength training (ST), and low- to medium-intensity and high-intensity training variables were monitored. Training loads were scaled as a percentage of the maximal volume measured at each intensity level. Four training periods (meso-cycles) were defined: the taper (weeks 1 to 2 before competition), short-term (weeks 3 to 5), medium-term (weeks 6 to 8), and long-term (weeks 9 to 11). Mixed-effects models were used to analyze the association between training loads in each training meso-cycle and end-of-season major competition performance. For sprinters, a 10% increase between ∼20% and 70% of the TTL in medium- and long-term meso-cycles was associated with 0.07 s and 0.20 s faster performance in the 50 m and 100 m events, respectively (p < 0.01). For middle-distance swimmers, a higher TTL in short-, medium-, and long-term training yielded faster competition performance (e.g., a 10% increase in TTL was associated with improvements of 0.1-1.0 s in 200 m events and 0.3-1.6 s in 400 m freestyle, p < 0.01). For sprinters, a 60%-70% maximal ST load 6-8 weeks before competition induced the largest positive effects on performance (p < 0.01). An increase in TTL during the medium- and long-term preparation (6-11 weeks to competition) was associated with improved performance. Periodization plans should be adapted to the specialty of swimmers.; En natation, la périodisation des phases d’entraînement précédant les compétitions majeures a été peu décrite. Nous avons modélisé les relations entre les 11 dernières semaines d’entraînement et les performances en compétition chez 138 nageurs élites. La charge d’entraînement totale (TTL), l’entraînement de force (ST), les variables d’entraînement de basse à moyenne et haute intensité ont été quantifiées. Les charges d’entraînement ont été normalisées en pourcentage du volume maximal individuel pour chaque niveau d’intensité. Quatre périodes d’entraînement (méso-cycles) ont été définies, l’affutage (semaines 1 à 2 avant la compétition), à court-terme (semaines 3 à 5), moyen-terme (semaines 6 à 8) et long-terme (semaines 9 à 11). Les modèles à effets mixtes ont été utilisés pour analyser les associations entre les charges d’entraînement dans chaque méso-cycle et la performance de fin de saison. Pour les sprinters, chaque augmentation de TTL de 10 % entre ∼20–70 % dans les méso-cycles à long et moyen-terme a été associée avec des performances plus rapides de 0,07 s et 0,20 s dans les épreuves de 50 m et 100 m (p < 0,01). Pour les nageurs de demi-fond une TTL plus élevée à court, moyen et long terme a induit des performances en compétition plus rapides (chaque augmentation de TTL de 10 % entre ∼20–70 % a été associée à des performances plus rapides de 0,3–1,6 s au 400 m, p < 0,01). Pour les sprinters, une ST entre 60–70 % 6–8 semaines avant la compétition a induit les effets positifs les plus élevés (p < 0,01). TTL 6–11 semaines avant la compétition a amélioré les performances en compétition.

International audience; Objective: Despite the indubitable beneficial effect of exercise to prevent of cardiovascular diseases, there is still a lack of studies investigating the impact of exercise in non-ischemic dilated cardiomyopathy. Here, we investigated the impact of voluntary exercise on cardiac function in a mouse model of non-ischemic dilated cardiomyopathy (αMHC-MerCreMer:Sf/Sf), induced by cardiac-specific inactivation of the Serum Response Factor.Materials and Methods: Seven days after tamoxifen injection, 20 αMHC-MerCreMer:Sf/Sf mice were assigned to sedentary (n = 8) and exercise (n = 12) groups. Seven additional αMHC-MerCreMer:Sf/Sf mice without tamoxifen injection were used as control. The exercise group performed 4 weeks of voluntary running on wheel (1.8 ± 0.12 km/day). Cardiac function, myocardial fibrosis, and mitochondrial energetic pathways were then blindly assessed.Results: Exercised mice exhibited a smaller decrease of left ventricular (LV) fractional shortening and ejection fraction compared to control mice. This was associated with a lower degree of LV remodeling in exercised mice, as shown by a lower LV end-systolic intrerventricular septal and posterior wall thickness decrease from baseline values compared to sedentary mice. Moreover, exercised mice displayed a reduced gene expression of atrial and brain natriuretic factors. These benefits were associated by a reduced level of myocardial fibrosis. In addition, exercised mice exhibited a higher mitochondrial aconitase, voltage-dependent anion-selective channel 1 and PPAR gamma coactivators-1 alpha proteins levels suggesting that the increase of mitochondrial biogenesis and/or metabolism slowed the progression of dilated cardiomyopathy in exercised animals.Conclusions: In conclusion, our results support the role of voluntary exercise to improve outcomes in non-ischemic dilated heart failure (HF) and also support its potential for a routine clinical use in the future.

International audience; Echoing scientific and industrial progress, the Twentieth century was an unprecedented period of improvement for human capabilities and performances, with a significant increase in lifespan, adult height, and maximal physiological performance. Analyses of historical data show a major slow down occurring in the most recent years. This triggered large and passionate debates in the academic scene within multiple disciplines; as such an observation could be interpreted as our upper biological limits. Such a new phase of human history may be related to structural and functional limits determined by long term evolutionary constraints, and the interaction between complex systems and their environment. In this interdisciplinary approach, we call into question the validity of subsequent forecasts and projections through innovative and related biomarkers such as sport, lifespan, and height indicators. We set a theoretical framework based on biological and environmental relevance rather than using a typical single-variable forecasting approach. As demonstrated within the article, these new views will have major social, economical, and political implications.

Purpose:To investigate the effect of different limb blood-flow levels on cycling-performance recovery, blood lactate concentration, and heart rate.Methods:Thirty-three high-intensity intermittent-trained athletes completed two 30-s Wingate anaerobic test sessions, 3 × 30-s (WAnT 1–3) and 1 × 30-s (WAnT 4), on a cycling ergometer. WAnT 1–3 and WAnT 4 were separated by a randomly assigned 24-min recovery intervention selected from among blood-flow restriction, passive rest, placebo stimulation, or neuromuscular electrical-stimulation-induced blood flow. Calf arterial inflow was measured by venous occlusion plethysmography at regular intervals throughout the recovery period. Performance was measured in terms of peak and mean power output during WAnT 1 and WAnT 4.Results:After the recovery interventions, a large (r = .68 [90% CL .42; .83]) and very large (r = .72 (90% CL .49; .86]) positive correlation were observed between the change in calf arterial inflow and the change in mean and peak power output, respectively. Calf arterial inflow was significantly higher during the neuromuscular-electrical-stimulation recovery intervention than with the blood-flow-restriction, passive-rest, and placebo-stimulation interventions (P < .001). This corresponds to the only intervention that allowed performance recovery (P > .05). No recovery effect was linked to heart rate or blood lactate concentration levels.Conclusions:For the first time, these data support the existence of a positive correlation between an increase in blood flow and performance recovery between bouts of high-intensity exercise. As a practical consideration, this effect can be obtained by using neuromuscular electrical stimulation-induced blood flow since this passive, simple strategy could be easily applied during short-term recovery.

National audience; Une blessureet la carrièresportive estsuspendue.Le mental affecté.La reprise incertaine.Un dispositif récent basésur les dernièresdécouvertes en neurologieet en neurosciences faitdes miracles à condition del’adapter à chaque athlète.Quand dire, imaginerou observer un gestesportif optimise la reprisede la pratique, redonneconfiance, voirerevient à s’entraîner.

Summary The clinical and biological follow-up of individuals, such as the biological passport for athletes, is typically based on the individual and longitudinal monitoring of hematological or urine markers. These follow-ups aim to identify abnormal behavior by comparing the individual’s biological samples to an established baseline. These comparisons may be done via different ways, but each of them requires an appropriate extra population to compute the significance levels, which is a non-trivial issue. Moreover, it is not necessarily relevant to compare the measures of a biomarker of a professional athlete to that of a reference population (even restricted to other athletes), and a reasonable alternative is to detect the abnormal values by considering only the other measurements of the same athlete. Here we propose a simple adaptive statistic based on maxima of Z-scores that does not rely on the use of an extra population. We show that, in the Gaussian framework, it is a practical and relevant method for detecting abnormal values in a series of observations from the same individual. The distribution of this statistic does not depend on the individual parameters under the null hypothesis, and its quantiles can be computed using Monte Carlo simulations. The proposed method is tested on the 3-year follow-up of ferritin, serum iron, erythrocytes, hemoglobin, and hematocrit markers in 2577 elite male soccer players. For instance, if we consider the abnormal values for the hematocrit at a 5% level, we found that 5.57% of the selected cohort had at least one abnormal value (which is not significantly different from the expected false-discovery rate). The approach is a starting point for more elaborate models that would produce a refined individual baseline. The method can be extended to the Gaussian linear model, in order to include additional variables such as the age or exposure to altitude. The method could also be applied to other domains, such as the clinical patient follow-up in monitoring abnormal values of biological markers.

International audience; The aim of this study was to quantify the impact of selections and shared selections in the rugby union. Players’ names, positions, and number of selections were collected for all XV de France’s games (1906–2014). Every team’s percentage of renewal of workforce was calculated for backs and forwards. During the 1987–2014 period, all second row forwards (locks), halfbacks, and centres’ shared selections (number of times when two players have competed together) were recreated. The Best vs. Rest method was applied to these remodelled dyads. They were analysed and compared with surrounding teammates as well as opponents. Head coaches similarly change their workforce for upcoming matches after winning or losing (around 30%), but losing teams renew significantly more positions in their line-ups. The recreated halfbacks, locks, and centres reveal a common pattern. Whether victorious or not, the ‘renewed couples’ victory percentage will congregate towards the XV de France’s victory percentage. For all the best recreated couples, the cumulated number of selections for forwards’ is always higher than the ones part of less efficient teams: 231.3 ± 80 vs. 212.9 ± 91 selections for locks’ teammates (Effect sizes (ES) small, possibly positive, 54.8%). In best recreated couples, number 8’s are significantly more experienced than their counterparts in less efficient pairs (ES small, likely positive, 76.3%). The XV de France’s collective effectiveness relies on a balance between stability and workforce renewal, which allows the building of specific position interactions and builds on experimented forwards packs. Selections and shared selections are serious collective performance parameters associated with performance.

International audience; We consider the problem of estimating a high-dimensional additive mixed model for longitudinal data using sparse methods. In this problem, multiple measurements are made on the same subject across time, and then the different sources of variability (intra- and inter-subject variability) and correlation within subjects have to be considered. Also, the relationships between explanatory variables and the outcome arepossibly non linear. In addition, the number of explanatory variables could be larger than the sample size but only a small set of explanatory variables contribute to the response.Several computational approaches for high-dimensional additive modelling for independent data have been developed in the literature. Recently, Amato and colleagues (Stat Methods Appl 2016; s10260-016-0357-8) conducted a comprehensive review of these methods. Efficient regularized estimation procedures for variable selection in nonparametric additive models use basis function approximations. The authors also proposed a reformulation of the estimation problem in terms of group Lasso that allows deducing convergence and asymptotic optimality properties.Only a few works have developed suggestions to analyse high-dimensional longitudinal data using Lasso-type methods in additive mixed model. The resulting estimator depends only on a relatively small number of basis functions, however variable selection is not directly encouraged. In this study we explore the extension of the group Lasso penalty to additive mixed effects models. We discuss computational aspects, including a comparison of group Lasso algorithms implemented through publicly available R codes, the estimation of optimal regularization parameter and linkages between mean and covariance parameter estimation algorithms. We illustrate the interest of such approaches in the analysis of a twenty - year longitudinal study of training practices of elite athletes.

International audience; Functional data analysis (FDA) and longitudinal data analysis (LDA) are the main approaches to analyze repeated measures data (in which multiple measurements are made on the same subject across time). Typically, FDA is applied when the data are dense, assumed to be observed in the continuum, and without noise. LDA is usually applied when data are sparse, possibly with different number of measurements across individuals, and subject to error.In elite sport, the parameters of the training program (intensity, volume, frequency, distribution and duration of high-intensity, recovery, and competition periods) should be manipulated systematically to optimize performance and reduce the risk of injury. Sport training data are recorded densely over time. However, measurements, such as duration of follow-up or duration of the season, vary among subjects. Subject-specific variations may introduce substantial measurement error.The statistical objectives of this study were the following:- First, to review the literature on the most commonly used methods for clustering of time evolution curves with a publicly available R code.- Second, to implement FDA and LDA methods presenting publicly available R code: k-means based on the standard Euclidian distance, a discrete Frèchet distance, and a distance of functions; Gaussian mixture model - based clustering for standard, longitudinal and functional data; and latent class mixed models.- Third, using data from a twenty - year longitudinal study of training practices of elite athletes, to perform a clustering analysis using relevant methods.- Fourth, to compare the results and interpret them. Comparison criteria were mainly based on computational and practical aspects.The practical goal of this project was to identify training profiles and to characterize them to provide relevant tools for supporting decision-making in monitoring athletes' training programs.

We give the asymptotic behavior of the Mann-Whitney U-statistic for two independent stationary sequences. The result applies to a large class of short-range dependent sequences, including many non-mixing processes in the sense of Rosenblatt. We also give some partial results in the long-range dependent case, and we investigate other related questions. Based on the theoretical results, we propose some simple corrections of the usual tests for stochastic domination; next we simulate different (non-mixing) stationary processes to see that the corrected tests perform well.

Aging is a complex, multi-scale process that affects all levels of biological organization from molecular structure to individual behavior. Locomotion is a highly integrated neurophysiological function that illustrates this process. The functional decline in locomotion with age has been described in a wide-range of species, both domestic and wild, and appears as a common aspect of senescence among animals. However, in most cases these descriptions remain incomplete and the dynamics of age-related changes are poorly understood. Here, we use a conceptual feature to describe age-related changes in locomotor performances for Caenorhabditis elegans, Mus domesticus, Canis familiaris, Equus caballus and Homo sapiens. We show that measurements of locomotor performance are consistent biomarkers of age-related changes, with a well preserved pattern regardless of the type of effort or duration. We also show that age-related pattern for locomotor performance are modulated by gender and environment. Nevertheless, in every case, the pattern remains similar and very well preserved. The second part of this work introduces the concept of phenotypic expansion and focuses on the expansion of the age-related pattern for Homo sapiens during the last century. Since the first edition of modern Olympic Games in 1896, athletes have consistently improved previous records, echoing scientific and industrial progress. Their data constitute privileged and accurate biomarkers, as sport performances reflect highly integrated neuro-physiological traits based on complex multifactorial interactions. Following the progression of the world records, the age-related pattern expanded gradually during the 20th century. However, the last decades show a slow-down in the expansion, following again the recent asymptotic levelling off of world records, which no longer supports the historical motto “Citius, Altius, Fortius”. This work provides new insights about the utility of an age-based comparative approach to provide a thorough understanding of aging processes and also for gaining insights into aging at different levels of biological organization and in an evolutionary perspective.; L’organisation biologique, du niveau moléculaire jusqu’au niveau des performances de l’organisme. La locomotion est une fonction neurophysiologique hautement intégrée illustrant un tel processus multi-échelle. Le déclin des performances de locomotion avec l’âge, comme la vitesse maximale, a été observé pour de nombreuses espèces, aussi bien en captivité qu’en milieu naturel. Cependant, ces descriptions restent souvent succinctes, sans précision sur la progression de ces performances au cours du vieillissement. Dans ces travaux, nous utilisons une équation bi-phasique pour décrire la relation entre performance de locomotion et âge sur l’ensemble de la durée de la vie pour Caenorhabditis elegans, Mus domesticus, Canis familiaris, Equus caballus et Homo sapiens. Les performances maximales de locomotion se révèlent être des bio-marqueurs robustes pour suivre la progression des performances sur l’ensemble de la durée de vie des animaux, permettant ainsi d’estimer le pic physiologique et le début du déclin des performances. De plus, dans tous les cas, nous remarquons que la forme de progression des performances maximales selon l’âge est similaire et conservée d’une espèce à l’autre ; seule varie la pente dans le temps, dépendant de l’espèce et la performance mesurée. L’observation des performances selon le genre ne montre pas de différence dans la forme de l’enveloppe. Néanmoins, elle révèle des écarts variables dans les performances maximales entre femelles et mâles selon les espèces. Enfin, les conditions thermiques affectent les performances maximales de locomotion, mais la forme de l’enveloppe reste aussi préservée. Nous avons ensuite étudié le développement et l’expansion de cette dynamique au cours du siècle dernier pour les performances athlétiques maximales d’Homo sapiens. Cette étude révèle que la forme s’est progressivement précisée au cours du temps en s’étendant à tous les âges et suivant homothétiquement la progression des records du monde. Néanmoins, la progression semble ralentir au cours des dernières décennies, laissant présager l’atteinte possible des limites biologiques d’Homo sapiens. Ces travaux offrent de nouvelles perspectives sur l’utilité des approches comparatives et l’utilisation d’un bio-marqueur comme les performances de locomotion pour suivre les dynamiques sur l’ensemble de la durée de vie à différentes échelles. Elles apportent aussi un regard novateur sur la progression des performances avec l’âge, en intégrant à la fois les processus de développement et de vieillissement, permettant ainsi de préciser les pics physiologiques et la forme des progressions des performances sur toute la durée de la vie.

Introduction: Mortality of people with diabetes is still high in France, as is their excess mortality compared with the general population. In this context, it is essential to understand the determinants of mortality in people with diabetes. The objective of this study was to examine the determinants of mortality in people with type 2 diabetes.Methods: The study population consisted in people with type 2 diabetes that replied to a self-administered questionnaire from the ENTRED 2001 and the ENTRED 2007 surveys. Participants were followed up until February 2013. Survival analyses were performed with a Cox model using age as a time scale. A subgroup analysis was conducted among participants for whom physicians had replied to a questionnaire.Results: Among the 7,218 participants, median age at inclusion and death were 65 and 72 years, respectively. The proportion of deaths was 21%.In multivariate analysis, determinants of mortality were: non-morbid obesity (RR=1.21, 95%CI: [1.02-1.43]) and morbid obesity (RR=1.76 [1.43-2.18]), diagnosis of diabetes established after symptoms (RR=1.19 [1.03-1.37]) rather than after a screening and tobacco consumption (RR=1.49 [1.26-1.77]), along with the fact of being a man (RR=1.76 [1.53-2.02]), participation in the 2007 ENTRED cohort vs. 2001 ENTRED cohort (RR=0.84 [0.74-0.95]), socio-economic category (with an excess risk in blue-collar workers (RR=1.36 [1.11-1.67]) compared to executives), registration for long term illness exemption (RR=1.29 [1.08-1.54]), treatment by insulin alone (RR=1.45 [1.21-1.74]) or by insulin and one or more oral antidiabetic drugs (RR=1.37 [1.12-1.68]) compared to a treatment based on one oral antidiabetic drug only, foot or renal complications (RR=1.97 [1.68-2.31]) and coronary complications (RR=1.39 [1.22-1.59]).Conclusion: Some determinants identified are widely modifiable. These results highlight the importance of prevention, which must involve appropriate therapeutic education in order to change lifestyles of people with type 2 diabetes, and improve the management of complications. This prevention must be adapted to the socio-economic profile of people with diabetes to reduce social inequalities observed in mortality linked with diabetes., Introduction : La mortalité des personnes diabétiques reste élevée en France, de même que leur surmortalité par rapport à la population générale. Dans ce contexte, la compréhension des déterminants de la mortalité des personnes diabétiques, peu étudiés en France, est essentielle. L’objectif de notre étude était d’étudier les déterminants de la mortalité des personnes diabétiques de type 2.Méthodes : La population d’étude était composée des personnes diabétiques de type 2 ayant répondu à un auto-questionnaire dans le cadre des enquêtes Entred 2001 ou Entred 2007. Les participants ont été suivis jusqu’en février 2013. Les analyses de survie ont été réalisées à partir d’un modèle de Cox utilisant l’âge comme échelle de temps. Une analyse de sous-groupe a été réalisée sur les personnes dont le médecin avait répondu à un questionnaire.Résultats : Parmi les 7 218 personnes incluses, les âges moyens à l’inclusion et au décès étaient respectivement de 65 et 72 ans. La proportion de décès était de 21%.En analyse multivariée, les déterminants de la mortalité étaient : l’obésité non morbide (RR=1,21, IC95%: [1,02-1,43]) et l’obésité morbide (RR=1,76 [1,43-2,18]), le diagnostic de diabète posé suite à des symptômes (RR=1,19 [1,03-1,37]) plutôt que suite à un dépistage et la consommation de tabac (RR=1,49 [1,26-1,77]), ainsi que le sexe masculin (RR=1,76 [1,53-2,02]), l’appartenance à la cohorte Entred 2007 par rapport à Entred 2001 (RR=0,84 [0,74-0,95]), le niveau socioéconomique (avec un sur-risque notamment chez les ouvriers (RR=1,36 [1,11-1,67]) par rapport aux cadres), le fait de bénéficier d’une affection longue durée (RR=1,29 [1,08-1,54]), le traitement par insuline seule (RR=1,45 [1,21-1,74]) ou par insuline associée à un ou des antidiabétiques oraux (RR=1,37 [1,12-1,68]) par rapport à un traitement par un seul antidiabétique oral et les complications podologiques ou rénales graves (RR=1,97 [1,68-2,31]) et coronaires (RR=1,39 [1,22-1,59]).Conclusion : Certains déterminants mis en évidence sont largement modifiables. Ces résultats rappellent l’importance de la prévention, qui doit passer par une éducation thérapeutique adaptée, afin de modifier le mode de vie des personnes diabétiques de type 2 et d’améliorer la prise en charge des complications. Cette prévention doit être adaptée au profil socioéconomique de la personne diabétique afin de réduire les inégalités sociales observées dans la mortalité liée au diabète.

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International audience; Introduction: Originally developed for astronauts, lower body positive pressure treadmills (LBPPTs) are increasingly being used in sports and clinical settings because they allow for unweighted running. However, the neuromuscular adjustments to unweighted running remain understudied. They would be limited for certain lower limb muscles and interindividually variable. This study investigated whether this might be related to familiarization and/or trait anxiety. Methods: Forty healthy male runners were divided into two equal groups with contrasting levels of trait anxiety (high, ANX+, n = 20 vs. low, ANX−, n = 20). They completed two 9-min runs on a LBPPT. Each included three consecutive 3-min conditions performed at 100%, 60% (unweighted running), and 100% body weight. Normal ground reaction force and electromyographic activity of 11 ipsilateral lower limb muscles were analyzed for the last 30 s of each condition in both runs. Results: Unweighted running showed muscle- and stretch-shortening cycle phase-dependent neuromuscular adjustments that were repeatable across both runs. Importantly, hamstring (BF, biceps femoris; STSM, semitendinosus/semimembranosus) muscle activity increased during the braking (BF: +44 ± 18%, p < 0.001) and push-off (BF: +49 ± 12% and STSM: +123 ± 14%, p < 0.001 for both) phases, and even more so for ANX+ than for ANX−. During the braking phase, only ANX+ showed significant increases in BF (+41 ± 15%, p

International audience

This study aimed to assess the effects of an off-season period of repeated-sprint training in hypoxia induced by voluntary hypoventilation at low lung volume (RSH-VHL) on off-ice repeated-sprint ability (RSA) in ice hockey players. Thirty-five high-level youth ice hockey players completed 10 sessions of running repeated sprints over a 5-week period, either with RSH-VHL (n = 16) or with unrestricted breathing (RSN, n = 19). Before (Pre) and after (Post) the training period, subjects performed two 40-m single sprints (to obtain the reference velocity (Vref)) followed by a running RSA test (12 × 40 m all-out sprints with departure every 30 s). From Pre to Post, there was no change in Vref or in the maximal velocity reached in the RSA test in both groups. In RSH-VHL, the mean velocity of the RSA test was higher (88.9 ± 5.4 vs. 92.9 ± 3.2% of Vref; p < 0.01) and the percentage decrement score lower (11.1 ± 5.2 vs. 7.1 ± 3.3; p < 0.01) at Post than at Pre whereas no significant change occurred in the RSN group (89.6 ± 3.3 vs. 91.3 ± 1.9% of Vref, p = 0.11; 10.4 ± 3.2 vs. 8.7 ± 2.3%; p = 0.13). In conclusion, five weeks of off-ice RSH-VHL intervention led to a significant 4% improvement in off-ice RSA performance. Based on previous findings showing larger effects after shorter intervention time, the dose-response dependent effect of this innovative approach remains to be investigated.

International audience; Achieving peak performance at a specified time is the primary goal of athletes’ training programs. To optimize performance and reduce the risk of injury, a comprehensive list of training program parameters (e.g. intensity, volume, frequency, distribution, duration and type) requires careful management. This work focuses on clustering of time evolution curves of training measurements.Training data are recorded densely over time. However, duration of follow-up and duration of the seasons vary among subjects. Also, subject-specific variation can induce substantial error. Functional data analysis (FDA) and longitudinal data analysis (LDA) are the main approaches to analyze repeated measures data (in which multiple measurements are made on the same subject across time). Typically, FDA is applied when the data are dense, assumed to be observed in the continuum, and a function of time. LDA is usually applied when data are sparse, possibly with different number of measurements across individuals, and subject to error. We compared several FDA and LDA methods implemented through publicly available R code: k-means based on the standard Euclidian distance, a discrete Fréchet distance [2], and a functional distance [1]; Gaussian mixture model–based clustering for standard [4], longitudinal [5] and functional [3] data; and latent class mixed models [6]. We discuss advantages and limitations including computational and practical aspects.References[1] Febrero-Bande, M. and Oviedo de la Fuente, M. (2012). Statistical computing in functional data analysis: the R package fda.usc. Journal of Statistical Software, 51, 1–28.[2] Genolini, C. and Falissard, B. (2011). Kml : A package to cluster longitudinal data. Computer Methods and Programs in Biomedicine.[3] Jacques, J. and Preda, C. (2013). Funclust: A curves clustering method using functional random variables density approximation. Neurocomputing, 112, 164–171.[4] Lebret, R., Iovleff, S., Langrognet, F., Biernacki, C., Celeux, G., and Govaert, G. (2014). Rmixmod: The R package of the model–based unsupervised, supervised and semi–supervised classification mixmod library. Journal of Statistical Software.[5] McNicholas, P. D. and Murphy, T. B. (2010). Model–based clustering of longitudinal data. Canadian Journal of Statistics, 38, 153–168.[6] Proust-Lima, C., Philipps, V., and Liquet, B. (2015). Estimation of extended mixed models using latent classes and latent processes: the R package lcmm. Technical report, University of Bordeaux. arXiv:1503.00890v2.

International audience; The conditions for high performance have changed considerably over the last few years. Athletes must spend more time training and competing, devote a lot of time to mental, physical and nutritional professionals and continue to respond to some constraints such as studying, spending time with their families, friends and quality of life. In this context and based on the work of Rosa, we wonder about the capacity of elite athletes to combine all these constraints, namely to manage the acceleration in their pace of life, in order to be able to achieve always more and better in the same time unit. To address this issue, we interviewed 42 French high-level athletes who train at the National Institute of Sport, Expertise and Performance (INSEP). Results show that to suit their goals, athletes implement arrangement and adjustment strategies aimed at making the time they have wholly useful and efficient. This time constraint puts athletes in a perpetual state of tension, on the verge of a good or poor life. The paper shows how the question of time, and particularly the acceleration of pace of life, is vital for modern sporting performance.

International audience; This study aims to characterize the relationships between intrinsic motivation towards physical activity, mindfulness, and physical activity level. We measured self-reported mindfulness, motivational regulation towards exercise, and physical activity level in 280 French students. Analyses conducted on 244 participants revealed that self-reported mindfulness moderates the relationship between intrinsic motivation towards exercise and physical activity levels. These findings may have implications for interventionists seeking to promote increased physical activity with mindfulness-based techniques. In fact, it seems that increasing mindfulness skills of individuals could improve their intrinsic motivation to exercise and thus, physical activity.

International audience; The effect of constitutive inactivation of the gene encoding myostatin on the gain in muscle performance during postnatal growth hsa not been well characterized. Methods. We analyzed 2 murine myostatin knockout (KO) models: i) the Lee model (KOLee) and ii) the Grobet model (KOGrobet), and measured the contraction of tibialis anterior muscle in situ. Results. Absolute maximal isometric force was increased in 6-month old KOLee and KOGrobet mice, as compared to wild-type mice. Similarly, absolute maximal power was increased in 6-month old KOLee mice. In contrast, specific maximal force (relative maximal force per unit of muscle mass was decreased in all 6-month old male and female KO mice, except in 6-month old female KOGrobet mice, whereas specific maximal power was reduced only in male KOLee mice. Discussion. Genetic inactivation of myostatin increases maximal force and power, but in return it reduces muscle quality, particularly in male mice.

International audience; La violence existe de tout temps, elle est consubstantielle à l’homme car « la relation humaineest une relation violente » (Pain, 2006). Un halo définitoire entoure ce vocable car la violence estprotéiforme et déclinée diversement selon le point de vue adopté et les époques. Il est vrai qu’àl’épreuve du temps, certains concepts sont passés d’une coloration positive à une coloration plusnégative, l’inverse étant vrai (Dugas, 2015).