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Yann Le Mansec Benjamin Pageaux Antoine Nordez Sylvain Dorel 《Journal of sports sciences》2018,36(23):2751-2759
ABSTRACTThis study aimed at evaluating the effects of mental and muscle fatigue on table tennis performance. Mental fatigue (MF) was induced by completion of 90 minutes of the AX-CPT; muscle fatigue was induced by completion of an eccentric exercise performed with the elbow flexors (biceps fatigue, BF) or the knee extensors (quadriceps fatigue, QF). The control condition consisted of watching a movie. Stroke parameters (speed and accuracy of the ball), as well as feelings of fatigue and force production capacity of the elbow flexors (BF, MF and control conditions) and knee extensors (QF condition), were assessed pre and post fatigue protocols. Feelings of fatigue increased post fatigue protocols. Force production capacity decreased only in the BF and QF conditions. BF and MF induced a decrease in accuracy. This decrease in accuracy was associated with an increased ball speed in the BF condition, and a decreased ball speed in the MF condition. QF had a negligible effect on stroke performance. Our results suggest that both mental fatigue, and muscle fatigue, significantly impair table tennis performance and therefore coaches should take into account both the physical and mental state of table tennis players to optimize performance. 相似文献
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Winter Olympic Games,cities, and tourism: a systematic literature review in this domain 总被引:1,自引:0,他引:1
The purpose of this study is to present the current state of scientific knowledge on the Winter Olympic Games (2000 to present-day) and their urban and tourism-related impacts. To achieve this, a scoping review was performed using established methodology. Of the 1694 English and French peer-reviewed sources identified from 14 different databases, 47 met the specific inclusion criteria and were retained for analysis. Findings were divided into three sections according to our objectives: (1) methodological profiles of the selected articles; (2) urban impacts; (3) tourism-related impacts. First, the reviewed sources – mainly qualitative – generally showed that mega-events such as the Winter Olympic Games are a catalyst for the urban renewal of host cities. However, these urban transformations must be part of a global scenario to ensure long-term viability. Although research shows that the Games represent an opportunity for the development of the tourism industry, the scoping review showed mixed results in terms of tourist flows and the enhancement of the city’s image. The concluding remarks identify the limitations of this study and offer opportunities and areas of research regarding the next Winter Games. 相似文献
23.
In the literature on new product development, most existing studies on the end of the design process concentrate on managing ramp-up in the field of manufactured products. This situation poses a problem at a time when our economies increasingly depend upon services and products are more and more related with sophisticated services that provide value for customers and producers. This article examines the management of the final phases of the design process of an innovative product-related service. Our research thus makes three contributions: (1) an analysis of the implementation process shows that the simultaneity of the production and consumption of a service means that three types of learning - technical, sales and uses - take place at the same time. Launch management strategies have thus to be adapted; (2) an analysis of the data collected confirms this difference by bringing to light great contrasts in these different aspects of learning; (3) this led us to identify a field that needs exploration by researchers in product and service innovation: the design of the sales process. Furthermore we underline two scenarios to manage the launch of innovative product-related services. 相似文献
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This study investigated maternal prenatal docosahexaenoic acid (DHA) intake and infant cognitive development at 22 months. Estimates for second‐ and third‐trimester maternal DHA intake levels were obtained using a comprehensive Food Frequency Questionnaire. Infants (n = 67) were assessed at 22 months on a novel object search task. Mothers' DHA intake levels were divided into high or low groups, with analyses revealing a significant positive effect of third‐trimester DHA on object search task performance. The third trimester appears to be a critical time for ensuring adequate maternal DHA levels to facilitate optimum cognitive development in late infancy. 相似文献
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In France, the existence of competition among schools and pupil flight from local public schools is not easily acknowledged because it calls into question established ideals concerning equality of opportunity and social integration through schooling. However, research on schools on the urban periphery shows that these phenomena are now quite common and reveal important changes in the functioning of schools and in perspectives and actual choices of parents. Faced with pupil flight to more prestigious public or private schools, local collèges create ‘good classes’, reinforce security and discipline and try to strengthen links with feeder schools to improve their image among parents. Parents, however, who are in search of guarantees of the existance of a good leaning environnement, have major doubts about the relevant criteria to judge school quality. Moreover, they differ strongly not only in the will to choose but in the ability to do so. The end result of these transformations in attitudes and behaviors is an increase in school segregation that can only be limited if important measures are taken to homogenize public school provision. 相似文献
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Yann Le Mansec Sylvain Dorel François Hug 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(4):442-452
This study aimed to compare the muscle activity of lower limbs across typical table tennis strokes. Fourteen high-level players participated in this study in which five typical strokes (backhand top, forehand top, forehand spin, forehand smash, flick) were analysed. Surface electromyography activity (EMG) of eight muscles was recorded (gluteus maximus, biceps femoris, vastus medialis, vastus lateralis, rectus femoris, gastrocnemius medialis, gastrocnemius lateralis, soleus) and normalised to the maximal activity measured during squat jump or isometric maximal voluntary contractions. The forehand spin, the forehand top and the forehand smash exhibited significant higher EMG amplitude when compared with other strokes. Both biceps femoris and gluteus maximus were strongly activated during the smash, forehand spin and forehand top (from 62.8 to 91.7% of maximal EMG activity). Both vastii and rectus femoris were moderately to strongly activated during the forehand spin (from 50.4 to 62.2% of maximal EMG activity) whereas gastrocnemii and soleus exhibited the highest level of activity during the smash (from 67.1 to 92.1% of maximal EMG activity). Our study demonstrates that offensive strokes, such as smash or forehand top, exhibit higher levels of activity than other strokes. 相似文献
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François Y. Doré Sylvain Fiset Sonia Goulet Marie -Chantale Dumas Sylvain Gagnon 《Learning & behavior》1996,24(2):142-149
Cats’ and dogs’ search behavior was compared in different problems where an object was visibly moved behind a screen that was then visibly moved to a new position. In Experiments 1 (cats) and 2 (dogs), one group was tested with identical screens and the other group was tested with dissimilar screens. Results showed that in both species, search behavior was based on processing of spatial information rather than on recognition of the visual features of the target screen. Cats and dogs were unable to find the object by inferring its invisible movement. They reached a high level of success only if there was direct perceptual evidence that the object could not be at its initial position. When the position change was indicated by an indirect cue, cats searched more at the object’s initial than final position, whereas dogs searched equally at both positions. Interspecific similarities and differences are interpreted in terms of the requirements for resetting working memory. 相似文献
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Sylvain Doussot 《Educational Action Research》2020,28(2):310-324
ABSTRACTKey studies in history education (from France and the USA) are discussed and compared in order to explore their methodological issues in terms of the types of knowledge they can generate about teaching and learning. An epistemological framework that relates the history of historians as an inquiry to that of the classroom provides the criteria for this comparative analysis, which is inscribed in Abbott’s epistemologico-institutional social sciences analysis through the identification of two basic debates that structure history education research, namely subject-matter knowledge vs pedagogical practices, and teaching and learning rules of methods vs habits of thinking. This analysis points out the conditions for the development of a formative school history inquiry (to have students work on their own explanations, to put into play their set of beliefs about history), which determine the modalities of a specific action research. These modalities are detailed by the example of an action research on the case of the teaching of the French Revolution in the last grade of primary school: the sharing of pedagogical (by the professor) and academic (by the researchers) decisions, the collective production of data throughout the process. 相似文献
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Drawing on the experience of training graduate students and researchers in qualitative and mixed-methods analysis since the mid-1990s, the authors reflect on the evolution of a multidisciplinary graduate course developed in a Canadian university since 2007. The hands-on/hands-off course design based on the use of NVivo was developed in parallel with a conceptual and reflexive position on methodology and multidisciplinarity in the context of an action research supported by their institution. This article exposes the four basic components of the course and the constructivist assessment model based on a term-long team analysis of original data created specifically for this purpose. The balance between collective and individual work, in-class and online exchanges, hands-on experience with the software and hands-off reflection is described and compared to recent pedagogical literature on the subject. The interest of this blended approach in fostering the development of the methodological expertise expected from researchers and graduate students, as well as the main issues and challenges facing this type of training in a research environment characterised by new approaches and tools, are discussed. 相似文献