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41.
This study aims to describe the intensity and load demands of different stage types within a cycling Grand Tour. Nine professional cyclists, whom are all part of the same World-Tour professional cycling team, participated in this investigation. Competition data were collected during the 2016 Giro d’Italia. Stages within the Grand Tour were classified into four categories: flat stages (FLAT), semi-mountainous stages (SMT), mountain stages (MT) and individual time trials (TT). Exercise intensity, measured with different heart rate and power output based variables, was highest in the TT compared to other stage types. During TT’s the main proportion of time was spent at the high-intensity zone, whilst the main proportion of time was spent at low intensity for the mass start stage types (FLAT, SMT, MT). Exercise load, quantified using Training Stress Score and Training Impulse, was highest in the mass start stage types with exercise load being highest in MT (329, 359?AU) followed by SMT (280, 311?AU) and FLAT (217, 298?AU). Substantial between-stage type differences were observed in maximal mean power outputs over different durations. FLAT and SMT were characterised by higher short-duration maximal power outputs (5–30?s for FLAT, 30 s–2?min for SMT) whilst TT and MT are characterised by high longer duration maximal power outputs (>10?min). The results of this study contribute to the growing body of evidence on the physical demands of stage types within a cycling Grand Tour. 相似文献
42.
This study examined if short-duration record power outputs can be predicted with the Anaerobic Power Reserve (APR) model in professional cyclists using a field-based approach. Additionally, we evaluated if modified model parameters could improve predictive ability of the model. Twelve professional cyclists (V?O2max 75 ± 6 ml?kg?1?min?1) participated in this investigation. Using the mean power output during the last stage of an incremental field test, sprint peak power output and an exponential constant describing the decrement in power output over time, a power-duration relationship was established for each participant. Record power outputs of different durations (5 to 180 s) were collected from training and competition data and compared to the predicted power output from the APR model. The originally proposed exponent (k = 0.026) predicted performance within an average of 43 W (Standard Error of Estimate (SEE) of 32 W) and 5.9%. Modified model parameters slightly improved predictive ability to a mean of 34–39 W (SEE of 29 – 35 W) and 4.1 – 5.3%. This study shows that a single exponent model generally fits well with the decrement in power output over time in professional cyclists. Modified model parameters may contribute to improving predictability of the model. 相似文献
43.
Mathieu Cynober Yukio Saito Nicolas Chaillet 《Journal of The Franklin Institute》2012,349(7):2313-2322
The objective of this work is the development of an automatic and mobile X-ray robot that is becoming necessary in a changing environment (aging society, growth of the developing countries, etc.). Specifically, there are three sides to such a project. First, there is the mechanical side, i.e. the design and implementation of motors on every mobile part of an X-ray unit allowing it to move around a standing patient. Then, comes the electronic side, i.e. the use of potentiometers and limit switches as feedback combined with microcontrollers. And last, the algorithm that computes three-dimensional models from two-dimensional X-rays. 相似文献
44.
Mathieu Lacome Julien Piscione Jean-Philippe Hager Chris Carling 《European Journal of Sport Science》2017,17(2):132-143
This study investigated end-game and transient changes in running activities and whether these were concomitantly associated with reductions in skill-related performance in senior international rugby union match-play. Altogether, 18 official matches were analysed (322 individual observations) using computerised video-based tracking and event coding (Amisco Pro®, SUP, Nice, France). In forwards and backs, trivial to small reductions (% difference: ?2.1, ±1.3 to ?10.0, ±4.0%) in total distance and that covered at high speeds (>18.0?km?h?1) occurred in the second- versus the first-half while there were trivial differences in skill-related performance measures (?2.3, ±4.5 to 7.5, ±14.0%). In both positions, small to moderate declines (?42, ±10 to ?21, ±7%) occurred in high-speed running in the final 10-min and 5-min periods versus mean values for all other 10-min and 5-min periods throughout the game while only small changes (?18, ±51 to 13, ±41%) in skill-related performance were observed. Trivial changes in running and skill-related performance (?11, ±74 to 7, ±39%) were observed in the 5-min period immediately following the most intense 5-minute periods of play compared to mean performance over the other 5-min periods. These findings suggest that international rugby union players were generally able to maintain skill-related performance over the course of match-play even when declines in running performance occurred. 相似文献
45.
Mathieu Quet 《Journal of Cultural Economy》2017,10(2):150-162
ABSTRACTThe past decade has seen an increase in anti-counterfeiting practices, especially in the pharmaceutical field. These practices aim at reducing the number of bad medicines available on the market, especially in countries where pharmaceutical regulation is still weak. But they have been accused of serving the interests of Big Pharma by reinforcing intellectual property instead of promoting better quality medicines. Based on a study of the controversies provoked by anti-counterfeiting laws and devices, this paper analyses anti-counterfeiting politics and shows: (a) the aim of this mode of government is to discriminate between medicines in order to regulate the value attached to distribution processes and (b) the tensions and contradictions which characterize anti-counterfeiting discourses and practices. As such, a central characteristic of pharmaceutical markets is the shift of value conflicts towards circulation and distribution rather than production. The securitization of pharmaceutical flows, rather than being in addition to the production of pharmaceuticals, emerges as a new disputed way of producing economic value, legality and social legitimacy for globalized technical commodities such as medicines. 相似文献
46.
Robert Hristovski Aleksandar Aceski Natalia Balague Ludovic Seifert Aleksandar Tufekcievski Aguirre Cecilia 《European Journal of Sport Science》2017,17(1):19-29
AbstractThe article discusses general structure and dynamics of the sports science research content as obtained from the analysis of 21998 European College of Sport Science abstracts belonging to 12 science topics. The structural analysis showed intertwined multidisciplinary and unifying tendencies structured along horizontal (scope) and vertical (level) axes. Methodological (instrumental and mode of inquiry) integrative tendencies are dominant. Theoretical integrative tendencies are much less detectable along both horizontal and vertical axes. The dynamic analysis of written abstracts text content over the 19 years reveals the contextualizing and guiding role of thematic skeletons of each sports science topic in forming more detailed contingent research ideas and the role of the latter in stabilizing and procreating the former. This circular causality between both hierarchical levels and functioning on separate characteristic time scales is crucial for understanding how stable research traditions self-maintain and self-procreate through innovative contingencies. The structure of sports science continuously rebuilds itself through use and re-use of contingent research ideas. The thematic skeleton ensures its identity and the contingent conceptual sets its flexibility and adaptability to different research or applicative problems. 相似文献
47.
Bouget M Rouveix M Michaux O Pequignot JM Filaire E 《Journal of sports sciences》2006,24(12):1297-1302
In this study, we examined the effect of rapidly increased training volume and intensity on hormonal responses (salivary cortisol [C] and urinary dehydroepiandrosterone sulphate [DHEA-S]) and recovery-stress state perceived by 12 female cyclists. Over the 4-day experimental period, there was an average increase in training load of approximately 122% compared with that during the previous 12 days. Scores on subscales of the Recovery Stress Questionnaire for Athletes increased for the somatic component of stress (Fatigue, Emotional Stress and Social Stress; P<0.05) and decreased the factor indicating recovery (General Well Being; P<0.05) after the heavy training period. The training programme increased resting concentrations of salivary cortisol (P<0.05) and decreased the DHEA-S/C ratio (P<0.05). The increase in training load of cyclists was correlated with this hormonal ratio (r=-0.48, P<0.05). Changes in resting cortisol concentration as a result of heavy training stress were positively related to the change in Physical Complaints (r=0.69, P<0.01). Negative relationships were also found between changes in the DHEA-S/C ratio and changes in the somatic component of stress. The present results suggest that there is a dose-response relationship between increased training load, resting DHEA-S/C ratio and subjective assessment of stress and recovery, implying that this ratio could be used as an indicator of training status in female athletes. 相似文献
48.
In this study, we examined the effectiveness of auditory concurrent feedback on body segmental alignment during the circle movement performed on a pommel horse. Eighteen gymnasts were assigned to one of two groups: a concurrent auditory feedback group (experimental) or a control group that received no concurrent feedback. After 2 weeks of training (300 circles), the body segmental alignment (BSA) of the experimental group had improved by 2.3% between the pre test (85.7 +/- 4.8% BSA(max)) and the post test (87.7 +/- 4.0% BSA(max)). Furthermore, the results of a retention test administered 2 weeks after the post test revealed no decline in performance for the experimental group. No gains in body segmental alignment were found for the control group. It was concluded that augmented auditory feedback made available in real time can be used to correct complex movements, such as the circle movement on a pommel horse, and does not appear to lead to information-dependence despite the frequent administration of feedback. The auditory signal available in real time could help gymnasts to become more objective about their own intrinsic information necessary for the refinement of the circle movement. 相似文献
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50.
Christian Fischer Leila S. Overney Mathieu Fauve Olaf Blanke Hansueli Rhyner Michael H. Herzog 《Journal of sports sciences》2013,31(14):1567-1576
Abstract Flexural and torsional rigidity are important properties of skis. However, the flexural and torsional rigidity that lead to optimal performance remain to be established. In the present study, four pairs of slalom skis that differed in flexural and torsional rigidity were tested by advanced and expert skiers. Using a 10-item questionnaire, different aspects of the skis' performance were rated on a 9-point scale. For each pair of skis, physical measurements were compared with the ratings of the two groups of skiers. Correlations (Spearman) were then determined between (i) different mechanical properties of the skis (static and dynamic), (ii) subjective assessments of the participants, and (iii) properties of the skis and the participants' assessments. The latter showed that expert skiers rate the aspects of the skis more accurately than advanced skiers. Most importantly, expert skiers are particularly sensitive to torsion of the skis. These results suggest that such highly rated elements should be addressed in future ski designs. 相似文献