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Résumé Objectifs Cette étude a comme objectif principal d'explorer l'influence de la fatigue sur les paramètres biomécaniques de la foulée mesurés par un accéléromètre portatif, le MyotestRun. Le protocole mis sur pied a permis des analyses complémentaires sur la reproductibilité et la sensibilité de l'outil utilisé. Méthode Trente-deux sujets masculins, répartis en deux groupes (Coureurs et Contrôle), ont réalisé un test d'effort progressif sur tapis roulant, des séquences de course à vitesse standardisée sur piste d'athlétisme et un test de temps limite à 90 % de la VMA sur piste. Les mesures biomécaniques obtenues à partir du MyotestRun ont permis d'explorer la reproductibilité des données, l'influence de la vitesse, les différences entre course sur tapis roulant et course sur piste ainsi que l'influence de la fatigue sur les paramètres biomécaniques. Résultats Les résultats montrent une excellente reproductibilité inter-essais des paramètres du MyotestRun à l'exception de l'asymétrie de la course. Aucune différence significative n'apparaît entre la foulée sur tapis roulant et la foulée sur piste. Le test progressif montre que tous les paramètres évoluent avec l'augmentation de la vitesse, confirmant la sensibilité du MyotestRun. L'étude met en évidence une modification de la foulée avec la fatigue qui se caractérise par un allongement du temps d'appui au sol et une diminution de la force, sans altération de la fréquence. Si l'étude met en évidence que l'évolution de la foulée avec la fatigue est plus uniforme dans le groupe Coureurs elle souligne également des adaptations à la fatigue qui peuvent être très différentes d'un sujet à l'autre. Conclusion Cette étude démontre d'une part, que le MyotestRun peut être un outil de terrain utile à l'analyse biomécanique de la course, et d'autre part, que l'influence de la fatigue sur la foulée, s'accorde avec la plupart des études tout en confirmant des différences interindividuelles très importantes. Summary Aims of the study The aim of the study was to investigate the influence of fatigue on stride biomechanics measured by a portable accelerometer, the MyotestRun. Opportunities of the protocol allowed additional analysis on the device reliability and sensitivity. Methods Thirty-two male subjects, divided in two groups (runners and control), were involved in the study and achieved a treadmill progressive VO2max test; repeated run at constant velocity on a track and a field test at 90% of the VvO2max until exhaustion. The biomechanical measurements obtained from the MyotestRun allow exploring the reliability, the influence of speed, the differences between treadmill and track stride and the influence of fatigue. Results Results show an excellent reproducibility of the MyotestRun values, except for the asymmetry of the stride. No significant stride difference appears between treadmill and track conditions. The progressive test shows that all the parameters evolve with speed increment, confirming the sensitivity of the MyotestRun. The study shows changes in the stride with the fatigue, such as an increase of the contact time, a decrease of the force. However any change in the stride frequency is observed. If the study shows that the fatigue pattern is more constant in the runners group it also highlights adaptations to fatigue that can be very different from one subject to another. Conclusion This study confirmed that MyotestRun is a useful device in the stride analysis. The influence of fatigue on the stride is in accordance with most of the studies while confirming very important interindividual differences. [ABSTRACT FROM AUTHOR]

Résumé: Objectif: L’objectif de cette étude est de vérifier, au sein d’une équipe de handball féminin s’entraînant trois fois par semaine, si l’introduction de deux courtes séances de musculation hebdomadaires présente un impact positif sur les qualités physiques des joueuses au cours de l’année. Population et méthode: Dix-huit joueuses de handball du meilleur niveau belge ont été suivies au cours d’une saison entière. Dix de ces filles (groupe ű Muscu Ƈ) ont bénéficié, en plus de leur entraînement normal, de deux séances de musculation hebdomadaire d’une durée de 30minutes. Les autres (groupe ű Contrôle Ƈ) ont suivi le même entraînement, sans les séances de musculation. Une batterie de tests (puissance des jambes, puissance des bras, détente verticale, sprint, lancer, souplesse) a été mise en place, à quatre reprises au cours de la saison, afin d’examiner l’évolution des performances musculaires. Résultats: Conformément à la littérature, le groupe ű Contrôle Ƈ ne montre aucune modification de performance au cours de l’année. Les résultats du groupe ű Muscu Ƈ montre, en revanche, que les séances de musculation ont été bénéfiques, avec des améliorations significatives, pour la puissance des jambes (p <0,005) et le sprint (p <0,05). L’amélioration de la détente se rapproche du seuil de signification (p =0,06) et la puissance des bras apparaît supérieure en fin d’année comparativement au groupe ű Contrôle Ƈ. [ABSTRACT FROM AUTHOR]

Abstract: Aims of the study: The aim of the present study was to explore the interest of inertial load-velocity and load-power relationships for establishing resistance training zones. Materials and methods: Thirty-five subjects went twice at the laboratory. The first session was used to determine bench press one repetition maximal (1RM) while the second session was used to determine load-velocity and load-power relationships by the means of an inertial dynamometer. For each subject, four major training zones (maximal velocity, power-velocity, strength-power, maximal strength), defined from the 1RM, were compared to the corresponding training zones defined from inertial load-velocity and load-power relationships. Results: Training zones defined from the 1RM are significantly different (P <0,001) from the ones based on load-velocity and load-power relationships. According to load-power and load-velocity relationships results, maximal bench press velocity should be trained from 0 to 23% of the 1RM; power-velocity should be trained from 25 to 54% of the 1RM; strength-power should be trained from 54 to 82% of the 1RM and maximal strength should be trained with superior loads. Such muscular profiles defined with inertial dynamometers allow a more acute and individualised prescription for power-velocity resistance training. [Copyright &y& Elsevier]

Abstract: Aims: To present the current status of the inertial muscular assessment. Current knowledge: This method stays feasible with very basic resistance training materials. The dynamometric approach, more accurate, presents growing interest in the sport context. Inertial assessment with submaximal loads allows the description of force–power–velocity relationships, the investigation of muscular fatigue or the kinematical analysis of movement. Rigorous protocols are requested in order to warrant the results reliability. Points of view and plans: Clarification of the recommendations to the users and of the protocol designing process seems indispensable. Perspectives of use appear numerous in sport pursuit, and may be interesting in some clinical contexts. Conclusion: The inertial dynamometric assessment appears like an accessible method which may revolutionize field muscular assessment. [Copyright &y& Elsevier]

Abstract: Introduction: The purpose of this study was to investigate the validity and reliability of an inertial dynamometer using accelerometry. Methods: Fourteen subjects were tested during three successive sessions at four increasing loads (30, 50, 70 and 95% of the 1RM). Maximal force, velocity and power performances were simultaneously assessed by the Myotest (Myotest S.A., Switzerland), an inertial dynamometer using accelerometry, and by another control valid dynamometer witch combine accelerometer and linear position transducer. At three first loads, only minor differences appeared in between both dynamometers, correlations were excellent and coefficients of variation were good and similar. However, at 95% of the 1RM, Myotest validity and reliability became insufficient. Conclusion: Bench press inertial assessment with accelerometer appeared valid and reliable at 30, 50 and 70% of the 1RM, but not at 95% of the 1RM. [Copyright &y& Elsevier]

Abstract: Introduction: This study used an iso-inertial dynamometer to investigate the influence of counter-movement and barbell throwing during bench press exercise. A critical analysis of these modalities during muscular evaluation was also performed. Methods: The action of muscle stretch during the counter-movement induced an increase in average velocity and a shortening of the time to reach the peak power and peak velocity. The barbell throwing did not alter the initial part of the movement yet lengthened the propulsive phase and delayed the braking phase. Consequently, maximal power and maximal velocity performances were improved. However, the throwing of the barbell requires its catch when falling down, which could be potentially harmful. Conclusion: The counter-movement and the throwing of the barbell significantly change the iso-inertial performances through a bench press exercise. The modalities of bench press assessment execution would have to be rigorously standardised. [Copyright &y& Elsevier]

Abstract: Introduction. – This study explored concentric and eccentric profile of knee musculature in a jumpers population. Relationships between isokinetic assessment and field tests performances have also been explored. Materials. – Jumpers population presented higher knee flexors performances in concentric and eccentric mode and superior knee extensors strength in eccentric. Significant correlations between isokinetics and field tests results were exclusively observed with athletes quadriceps performances. A very high correlation (r =0.93) was found between the second bound relative performance of the ten multijumps test and eccentric quadriceps relative peak torque. Conclusion. – Jumpers training may favour a specific muscular development. The knee extensors eccentric strength may be a major factor in the athletic performance. [Copyright &y& Elsevier]

Summary Aims of the study The first aim of this study was to set a battery of field tests in order to assess specific muscular function of biketrial riders. The second aim was to investigate the discrimination of these tests by comparing the performance of elite and amateur riders. Material and method Twenty ELITE biketrial riders and 13 biketrial amateurs (AMAT) underwent field tests. The battery of field tests consisted in four non specific jumping tests (SJ, CMJ, SBJ and Reactivity) and three original specific tests on the bike (bike gap, side-hop over an elastic and holding time on the back-wheel). All the tests were performed on the field with portable equipment. Results The results show that bike specific tests are very discriminant: ELITE riders were significantly superior in each test (P < 0.001) The 20in riders seem to have a greater jumping ability in comparison with the 24in riders. The correlation between the jumping field tests and the bike specific tests is fairly high (r > 0.7). Conclusion The field tests as well as the bike specific tests showed to be selective and discriminant for the biketrial rider's. Jumping ability appears to be very important in order to achieve the elite level. [ABSTRACT FROM AUTHOR]

Introduction From 3 to 6-years-old, it is very important to offer children an adapted physical education intervention in which they are playing and at the same time develop perceptual and basic fundamental movement skills. In Belgium, most teachers are meeting recurrent problems like big classes, insufficient infrastructures and equipment that have not been appropriately adapted. All these reasons have encouraged the CEReKi to organize sport classes in its sport centrum in order to offer an adapted physical education to 3- to 6-years-old children. Implemented project In the last twenty years, preschool children have attended our sports centre for whole day sport classes. Most classes occur once or twice a month. According to Harrow's taxonomy, it is important to focus on fundamental motor skills and on perceptual abilities. The day at CEReKi starts at 9:30 am and ends at 3 pm. There are five activities lasting 30 to 45 minutes throughout the day and include water-based learning and gymnastic circuits. We select a range of different activities with nine categories of games (gymnastics, track and field, balls, small equipment, water based learning, etc.) Activities are organized either as free game, game with rules or as circuits. Our teaching is adapted to the children and encourages fun and enjoyment. Through the use of appropriate games and stories, we try to engage with the children also on an emotional level so that they join in the game and are as active as possible. Critical analysis Sport classes at the CEReKi are really appreciated by children. The keys to our success are: (a) good knowledge of child development; (b) knowledge of the equipment; (c) adaptation to level of the child; (d) using stories and imagination; (e) safety; (f) enthusiastic and communicative instructors. However, such an approach is only viable with financial support. Conclusion Sport classes at the CEReKi are a successful and useful concept that deserve to be disseminated. Similar organizations should emerge to support children's fundamental motor development but they will require financial support. [ABSTRACT FROM AUTHOR]

Introduction Premature infants are more susceptible to motor development impairment when compared to full term infants [1] . The effects of these impairments that are manifested in the long-term can be prevented through adapted psychomotor stimulation and early parental guidance. From this perspective a psychomotor program has been implemented for very pre-term children aged from 18 to 36 months. The aim of the present study was to validate the project. Methods Before the project started instance several experts were consulted. Ten children took part in this project from January to April 2011. The staff consisted of a psychomotor specialist and a physiotherapist. The activity was structured as follows: – welcome and familiarization (5–10 min); – undirected activity stimulating fine and gross motor skills (45 min); – return to calm (5 min). During the activity, the staff suggested different games and exercises in order to stimulate the children. The children were never forced to do the exercises. Interviews were conducted with parents, instructors and experts in order to validate the implemented project. They were asked to they give their opinion on the project, to confirm or deny our choices and to make suggestions about the activity. Results The initial project has been well designed. The objectives, the activity model and its structure, the staff and pedagogy have been validated by the experts. In order to stimulate infant autonomy it has been decided that no parent will be present during the activity although this particular point is controversial. Financial aspects have also to be considered as the activity is not subsidized. Conclusion Most elements of the implemented psychomotor activity were validated by the experts and the parents. However, financial support is needed for this work to be sustained. [ABSTRACT FROM AUTHOR]

Summary Objectives This review article aimed to summarize the current state of understanding on creatine supplementation for soccer players. In other words, it investigated the beneficial (and potentially negative) effects of this supplementation on sport-specific skills and performance in soccer players. Furthermore, this article accordingly discussed the safest and most recommended protocols for the consumption of creatine by these athletes. News Studies have shown that creatine supplementation can have positive effects on sprint and vertical jump performances in soccer players. This supplementation may also enhance soccer players’ muscle strength and adaptation to a high-intensity training regimen. Besides, creatine may be able to enhance muscle glycogen (as well as phosphocreatine) storage, reduce oxidative stress, and improve muscular repair and hypertrophy. Interestingly, creatine supplementation does not seem to affect aerobic performance. Prospects and projects Soccer players could take creatine during pre-season training (3 to 5 g/day) in order to help them endure a high-intensity training regimen and enhance their muscular strength and adaptation resulting from strength and/or resistance training. A lower dosage (less than 3 g/day) might also be sufficient and beneficial during the season in case of fatigue, in order to sustain adequate levels of phosphocreatine and glycogen in the muscles. Occasional intakes (about 3 g) before games and/or extenuating practices could also give a physical and mental boost to the players. Conclusion Most of the studies measured the effects of creatine on skills or physical performances in isolation from the true athletic demands of soccer match play. In conclusion, there is still a need for more research in order to determine whether creatine supplementation is ergogenic regarding the (aerobic) capacity to repeat (very) high-intensity actions, more particularly during competitive soccer. [ABSTRACT FROM AUTHOR]

Introduction/Background Patients with Parkinson's disease (PD) have a reduced physical activity level, although exercise is especially recommended in this population [1] . Besides, motor and non-motor symptoms may also interfere with the ability to produce strenuous efforts. Yet, their baseline performances and the response to physical reconditioning have not been thoroughly investigated. The cross-sectional part of this study investigates different aspects of physical fitness of patients suffering from mild-to-moderate PD. The second part investigates the response to physical reconditioning. Material and method Sixty PD patients and 47 healthy controls (HC) matched for demographic features were tested for aerobic performances and muscle strength. Peak work load (PWL) and peak oxygen consumption (VO 2 peak) were assessed in both groups during an incremental cycle exercise test. Isokinetic knee muscle strength (IKMS) was also tested for the extensor and flexor muscles at 60° and 180°.s −1 . Subgroups of PD patients were also allocated to 12 weeks of strength training (ST, n = 17), aerobic training (AE, n = 20) or standard care control intervention ( n = 15). Results In comparison to HC, PD patients showed reduced PWL and VO 2 peak (respectively −19% and −14%, P ≤ 0.003). PD patients showed reduced IKMS of flexor muscles (from −17 to −24%, P ≤ 0.001), and reduced IKMS only for the most affected side of extensor muscles (−13%, P ≤ 0.015). Eighty-eight percent and 80% of the trained patients respectively completed the ST and the AE interventions. No major complication occurred during the interventions. The AE group improved PWL (+18%, P = 0.001) and VO 2 peak (+12%, P = 0.033). The ST group improved IKMS of flexors (+22–25%, P ≤ 0.02), IKMS of extensors only for the most affected side (+10–17%, P < 0.05), and PWL (+16%, P < 0.001). Conclusion Aerobic and strength performances are both affected by PD. However, physical reconditioning is feasible and improves fitness of PD patients. [ABSTRACT FROM AUTHOR]

Introduction En Belgique, les compétitions proposées aux enfants de moins de 10 ans sont des modèles réduits des compétitions adultes et sont axées sur la performance, avec peu d’engagement moteur, favorisant une spécialisation et un élitisme précoce. Pourtant, à l’échelle internationale, l’IAAF recommande depuis plus de dix ans un modèle de compétition adapté aux enfants avec des activités motivantes, accessibles et formatrices : le Kids’Athletics © [1] . Face au constat de retard, la Ligue Francophone Belge d’Athlétisme a mis sur pied un groupe de réflexion qui a décidé d’organiser une première compétition Kids’Athletics © . Structure mise en place Tous les clubs régionaux ont été invités à former des équipes d’enfants âgés entre 5 et 8 ans afin de participer au Kids’Athletics. Sept épreuves de courses, de sauts et de lancers, largement inspirées des fiches proposées par l’IAAF [1] , étaient réalisées par toutes les équipes. La compétition était organisée de façon à se dérouler en 3 heures, échauffement et remise des diplômes compris. Analyse critique Seulement trois clubs ont répondu présents. Cette déception s’explique par le manque de connaissance des clubs, des réticences, un désintérêt, la concurrence avec d’autres évènements ou encore une promotion limitée. Des questionnaires distribués aux parents et aux entraîneurs présents ont permis de discerner leurs connaissances et leur avis sur le Kids’Athletics © . Bien que le concept s’avère mal connu, les avis apparaissent très positifs après la compétition. Les questionnaires révèlent que les enfants se sont amusés et 96 % des intervenants sont favorables au développement et à la promotion du concept. Seulement 7 % préfèrent le modèle de compétition traditionnel. Conclusion Le développement des Kids’Athletics © en Belgique devrait contribuer à une pratique de l’athlétisme mieux adaptée chez les enfants. Les nombreuses réticences existantes nécessitent la mise sur pied d’une promotion bien réfléchie et convaincante. [ABSTRACT FROM AUTHOR]

Introduction/Background Being physically active protects the elders against cerebral grey matter (GM) loss in regions particularly exposed to aging [1] . This cross-sectional study extended this hypothesis by searching correlations between volume or microstructure of GM and physical fitness in the nigrostriatal system of patients suffering from Parkinson's disease (PPD). Material and method Cerebral grey matter volume (GMV), magnetization transfer (MT) and R2* (an index of local iron) parameters were extracted from whole brain 3 T MRI and were analysed voxel-by-voxel using SPM12 in 42 PPD and 32 matched healthy controls (HC). All subjects were also tested for Peak work load (PWL) and knee flexor strength (KFS). First, we performed a two-sample t -test to look at areas affected in the nigrostriatal system of the PPD in comparison to HC. Next, we used a regression analysis to test which of these regions, if any, showed a relationship between (1) GMV, MT or R2* and (2) individual PWL or KFS. Results The comparative study showed increased R2* in bilateral SN, reduced GMV and increased R2* in left and right striata ( P uncorrected < 0.001). In PPD, GMV in the head of the right caudate nucleus and anterior putamen showed a positive correlation with PWL and GMV ( P corrected < 0.023). Besides, GMV in this cluster also correlated with global cognitive performance assessed by the Mattis Dementia Rating Scale ( P corrected < 0.024). None of the disturbed regions correlated with KFS. No significant correlations were observed in these regions for HC. Conclusion Aerobic fitness may have a specific neuroprotective effect on the right anterior striatum of PPD, and this could be associated with better cognition. [ABSTRACT FROM AUTHOR]

Introduction L’accoutumance à l’eau apparaît comme un pré-requis indispensable à l’apprentissage des techniques de nages [1] . Les difficultés pédagogiques rencontrées dans certaines piscines pour l’accoutumance à l’eau (pas de pataugeoire, profondeur excessive, taux d’encadrement) ont poussé le CEReKI à développer un circuit d’accoutumance original basé sur un assemblage de matériel [2] . L’objectif de l’étude est de vérifier l’efficacité de l’approche CEReKI comparativement à une approche traditionnelle réalisée dans un contexte idéal. Méthodes Une batterie de tests [3] a permis d’évaluer le niveau d’accoutumance à l’eau de 77 enfants préscolaires avant et après une période d’intervention de 5 mois. Vingt-cinq enfants bénéficiaient d’une piscine optimale (3 bassins) et d’une approche pédagogique traditionnelle (tradition). Vingt-cinq autres bénéficiaient de l’approche pédagogique CEReKi dans une piscine peu adaptée (CEReKI). Les 27 derniers ne bénéficiaient d’aucun cours d’acclimatation (témoin). L’approche pédagogique et le comportement des enfants ont été analysés dans les 2 écoles à partir d’enregistrements vidéo. Résultats Le niveau d’accoutumance à l’eau, qui évolue naturellement avec l’âge, s’améliore significativement du pré-test au post-test quel que soit le groupe. Les résultats démontrent cependant des gains plus importants dans les deux écoles d’accoutumance à l’eau comparativement au groupe témoin (respectivement 16,5 %, 19,2 % et 11,8 %). L’Anova révèle que cette supériorité est statistiquement significative ( p < 0,05) pour les qualités « flottaison-équilibration » et « propulsion ». L’analyse statistique ne démontre pas la supériorité d’une approche par rapport à une autre. Cependant, le nombre de séances et la durée de celles-ci étaient plus faibles dans le groupe CEReKI, ceci tend à indiquer une meilleure rentabilité de l’approche CEReKI. Cette dernière apparaît donc particulièrement efficace dans une piscine peu adaptée aux activités d’accoutumance à l’eau. Conclusion L’étude confirme l’efficacité de l’accoutumance à l’eau chez l’enfant préscolaire. L’approche CEReKI se montre particulièrement intéressante pour les piscines peu adaptées à l’accoutumance à l’eau. [ABSTRACT FROM AUTHOR]

Introduction Au CEReKi, les activités d’accoutumance à l’eau se déroulent dans un bassin dont la profondeur minimale est de 80 cm. Seuls certains enfants de maternelle sont capables de s’y tenir debout. Dès lors, comment proposer une activité adaptée à ces enfants dans un bassin inadapté tout en respectant les importantes différences de niveau observées dans cette tranche d’âge ? Le CEReKi a développé une solution pour relever le défi. Expérience Afin de permettre l’évolution en toute autonomie des enfants en l’absence de « petite profondeur », le CEReKi a mis en place un « jardin d’accoutumance à l’eau ». Il s’agit d’un circuit qui associe différentes sortes de matériel, permettant aux enfants de se déplacer dans l’eau « sans avoir pied ». Barres parallèles, tapis flottants, toboggan sont reliés à un filet flottant tendu à fleur d’eau. Dans le « jardin d’accoutumance », chaque enfant évolue à son propre rythme. Le circuit permet de stimuler les différents composants de l’accoutumance à l’eau : entrée à l’eau, maîtrise de la position horizontale, immersion, respiration et propulsion. Ce dispositif peut accueillir simultanément 25 à 30 élèves de niveaux d’aisance aquatique différents. Analyse critique Le succès de cette activité et les progrès observés chez les enfants confirment l’efficacité du « jardin d’accoutumance ». Ce dernier nécessite cependant l’acquisition d’un équipement aquatique de qualité qui, par ailleurs, doit être stocké à proximité du lieu de l’activité. Un temps de montage/démontage de quinze minutes est à prévoir avant et après chaque activité. La formation des animateurs, très importante, insistera sur le montage du circuit, la sécurité et l’approche pédagogique. Conclusions Le jardin d’accoutumance à l’eau CEReKi semble offrir une solution pour toutes les piscines, particulièrement pour celles qui ne disposent que d’un grand bassin. [ABSTRACT FROM AUTHOR]