A Medal in the Olympics Runs in the Family: A Cohort Study of Performance Heritability in the Games History

Introduction: Elite performance in sports is known to be influenced by heritable components, but the magnitude of such an influence has never been quantified.Hypothesis/Objectives: We hypothesized that having a former world-class champion in the family increases the chances of an athlete to repeat the achievement of her or his kinship. We aimed to measure the heritability of a medal in the Olympic Games (OG) among Olympians and to estimate the percentage of the genetic contribution to such a heritance.Study Design: Twin-family study of a retrospective cohort.Methods: All the 125,051 worldwide athletes that have participated in the OG between 1896 and 2012 were included. The expected probability to win a medal in the OG was defined as the frequency of medallists among Olympians without any blood kinship in the OG. This expected probability was compared with the probability to win a medal for Olympians having a kinship (grandparent, aunt/uncle, parent, or siblings) with a former Olympian that was a (1) non-medallist or (2) medallist. The heritability of the genetically determined phenotype (h2) was assessed by probandwise concordance rates among dizygotic (DZ) and monozygotic (MZ) twins (n = 90).Results: The expected probability to win a medal in the OG was 20.4%. No significant difference of medal probability was found in the subgroups of Olympians with a Non-medallist kinship, except among siblings for whom this probability was lower: 13.3% (95% CI 11.2–14.8). The medal probability was significantly greater among Olympians having a kinship with a former Olympic Medallist: 44.4% for niece/nephew (33.7–54.2); 43.4% for offspring (37.4–48.6); 64.8% for siblings (61.2–68.8); 75.5% for DZ twins (63.3–86.6); and 85.7% for MZ twins (63.6–96.9); with significantly greater concordance between MZ than DZ (p = 0.01) and h2 estimated at 20.5%.Conclusion: Having a kinship with a former Olympic medallist is associated with a greater probability for an Olympian to also become a medallist, the closer an athlete is genetically to such kinship the greater this probability. Once in the OG, the genetic contribution to win a medal is estimated to be 20.5%

Optimisation des performances, complexité des systèmes et confrontation aux limites

National audienceLe but de ce chapitre est de comprendre les conditions de la performance : son moteur, son énergie, ses rendements, ses bénéfices premiers et seconds. Il s'agira de concevoir ensuite, sur quelques exemples, ce qui fonde les raisons théoriques de nos limites, et de vérifier que les situations observées sont en accord avec les constructions conceptuelles. Enfin, nous chercherons à connaître le contexte présent de la performance, les raisons du dépassement, les fondements de l'optimisation et les métamorphoses de cette quête perpétuelle

FACE AUX PROGRÈS CONSTANTS DE LA SÉDENTARITÉ, LES GOUVERNEMENTS DOIVENTPROMOUVOIR TOUTES LES STRATÉGIES FAVORISANT L’ACTIVITÉ PHYSIQUE OU SPORTIVE

National audienceL’activité physique ou sportive (APS) constitue unvéritable phénomène de société. Tant par ses conséquenceséconomiques ou culturelles que par seseffets sanitaires, le corps en mouvement devientenjeu d’équilibre quotidien pour nos concitoyensautant qu’objet d’étude pour les sciences humaineset les sciences de la vie et, plus encore, une cible despolitiques internationales de santé et d’éducation

Prediction of one-repetition maximum from submaximal ratings of perceived exertion in older adults pre-and post-training

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Physiotherapy Intervention for Joint Hypermobility in Three Cases with Heritable Connective Tissue Disorders

peer reviewedIntroduction: In Joint Hypermobility Syndromes, chronic pain is the most disabling symptom. Its origin can be multiple (i.e. subluxations, sprains, pathologies of tendons, ligaments, peripheral nerves, multiple operations). The goal of this article was intended to discuss appropriate physiotherapy in hyperlax patients. Patients and Method: The recovery process was analyzed in three cases (Marfan Syndrome, Ehlers-Danlos Syndrome and Osteogenesis Imperfecta). Hypermobility was assessed using the Brighton scale, pain using the Visual Analogue Scale and quality of life using the Medical Outcome Study Short Form-36. Bone density was evaluated by QDR X-ray absorptiometry. We emphasized that it was important to avoid stretching and to train the patient within a controlled range of motion. Submaximal eccentric exercises within a safe range of motion were incorporated to increase the active control of the joint positioning. Thus, in one patient, isokinetic rehabilitation was successfully undertaken. Each treatment had to be adapted to the individual patient and had to include specific home exercises. Conclusion: In each case, physiotherapy gave good results in relation to pain, quality of life and stability of rehabilitated joints. Safety must be assured and specific evaluations such osteodensitometry, cardiac explorations and interventions of bracing, proprioceptive and functional strengthening can be very helpful

Application des principes de la classe inversée aux travaux pratiques de physique

Une enquête interne au sein du département de Physique de l’Université de Liège (Belgique) a révélé que les assistants en charge des travaux pratiques considéraient importante l’aide qu’ils apportent aux étudiants en laboratoire. Malgré cela, les assistants sondés considèrent que les étudiants sont insuffisamment motivés lors de leur arrivée et observent un manque d’investissement dans la tâche au cours de ces laboratoires. En réponse à ces constats, un projet a été développé afin de tenter de faciliter la compréhension de la matière par les étudiants et d’accroître leur motivation à s’investir davantage dans leur formation, et en particulier, lors des travaux pratiques de physique. Basé sur le principe de la classe inversée, ce projet consiste en la réalisation de courtes séquences vidéo introductives aux travaux pratiques. Elles ont notamment pour objectif de présenter la matière sous une autre forme que celle utilisée lors des cours en classe. Concrètement, une première séquence est publiée quelques jours avant le laboratoire. Les concepts de base y sont illustrés et rapidement mis en application. Les étudiants sont alors invités à commenter une application particulière et non expliquée. Quelques jours plus tard, une seconde séquence vidéo est postée. Elle comprend la solution au problème et la présentation du matériel de laboratoire. Ces vidéos ont été conçues en accord avec les standards pédagogiques en la matière au niveau de la durée, de la distribution de la charge cognitive et des principes du multimédia. Une attention particulière a été apportée afin de rendre signifiante la matière enseignée au public particulier auquel elles s’adressent. Enfin, un test formatif composé de QCM permet à l’étudiant de s’auto-évaluer avant le laboratoire. Une analyse portant sur une éventuelle augmentation des notes obtenues aux questions en rapport avec ces deux laboratoires et sur la satisfaction des étudiants et des assistants sera effectuée

Innovative Weak Formulation for The Landau-Lifshitz-Gilbert Equations

A non-conventional finite element formalism is proposed to solve the dynamic Landau-Lifshitz-Gilbert micromagnetic equations. Two bidimensional test problems are treated to estimate the validity and the accuracy of this finite element approachComment: 4 pages, proceedings for Intermag Madrid, May 2008 (oral contribution

Geographic enrollment of the top 100 in athletics running events from 1996 to 2012

International audiencePurpose It is widely accepted in the literature that athletes of West African origins achieve the best sprint performances; while, athletes originating from East Africa are the most efficient at long distances. No epidemiological studies have measured the evolution of the contributing of each of these athlete origin groups from 100m to the marathon.Method Speed, morphology and geographic origin of the Top 100 male and female athletes (from 100m to the marathon) were collected and analyzed over the 1996-2012 period.Results The amount of male sprinters (100m, 200m and 400m) originating from West Africa increased from 57.7% in 1996 to 72.3% in 2012, while female sprinters from West Africa increased from 55% to 65% over the same period. This contribution has gradually increased from 400m to 100m for both sexes. For long distance events (3000m, 10000m and marathon), male athletes from East Africa represented 32% in 1996, which increased to 65.7% in 2012 and increased over the same period from 9% to 39% for women. In addition, male and female sprinters originating from West Africa have a significantly higher (p<0.05) BMI than athletes of other geographic origin. Conversely, long distances runners' BMI are significantly lower for runners with an East African origin (p<0.05).Conclusions The best performances are dominated by a few groups including the West African ancestry for the sprint distances and East African runners for the long distances. This dominance is strengthened from 1996 to 2012 for both sexes to the detriment of Caucasian and Asian athletes

Aux limites de la performance

International audienc