Constraints on competitive performance of attacker-defender dyads in team sports     

Vilar L  Araújo D  Davids K  Travassos B 《Journal of sports sciences》2012,30(5):459-469

Previous research on coordination dynamics of 1 vs. 1 sub-phases in team sports has reported stable emergent patterns of coordination in the displacement trajectories of attackers and defenders. The aim of this study was to use attacker-defender interactions in competitive team match-play to investigate how the locations of the goal and ball constrain the pattern-forming dynamics of attacker-defender dyadic systems. Ten high-level futsal matches were filmed and 13 goal sequences selected for analysis. Displacements of the players and the ball were filmed and digitized from 52 attacker-defender dyadic system interactions. Results showed that, although attackers and defenders exhibited similar angular orientations to the goal, the latter always remained closer to the goal than attackers. Observations revealed that in-phase patterns of coordination emerged from changes to both the distances and angles of attackers and defenders to the goal. Attackers always remained closer to the ball than defenders, while the latter exhibited a lower angle to the ball than attackers. A pattern of in-phase coordination modes emerged between the attackers and defenders' distances and angles to the ball. This study helps us to understand interpersonal interactions in team sports by explaining how attackers and defenders use information about their relative positioning to the goal and the ball to perform successfully.  相似文献   

Interpersonal coordination tendencies shape 1-vs-1 sub-phase performance outcomes in youth soccer   总被引：2，自引：2，他引：0  

Duarte R  Araújo D  Davids K  Travassos B  Gazimba V  Sampaio J 《Journal of sports sciences》2012,30(9):871-877

This study investigated the influence of interpersonal coordination tendencies on performance outcomes of 1-vs-1 sub-phases in youth soccer. Eight male developing soccer players (age: 11.8 ± 0.4 years; training experience: 3.6 ± 1.1 years) performed an in situ simulation of a 1-vs-1 sub-phase of soccer. Data from 82 trials were obtained with motion-analysis techniques, and relative phase used to measure the space-time coordination tendencies of attacker-defender dyads. Approximate entropy (ApEn) was then used to quantify the unpredictability of interpersonal interactions over trials. Results revealed how different modes of interpersonal coordination emerging from attacker-defender dyads influenced the 1-vs-1 performance outcomes. High levels of space-time synchronisation (47%) and unpredictability in interpersonal coordination processes (ApEn: 0.91 ± 0.34) were identified as key features of an attacking player's success. A lead-lag relation attributed to a defending player (34% around -30° values) and a more predictable coordination mode (ApEn: 0.65 ± 0.27, P < 0.001), demonstrated the coordination tendencies underlying the success of defending players in 1-vs-1 sub-phases. These findings revealed how the mutual influence of each player on the behaviour of dyadic systems shaped emergent performance outcomes. More specifically, the findings showed that attacking players should be constrained to exploit the space-time synchrony with defenders in an unpredictable and creative way, while defenders should be encouraged to adopt postures and behaviours that actively constrain the attacker's actions.  相似文献   

Challenges and strategies of building and sustaining inter-organizational partnerships in sport for development and peace     

Jon Welty Peachey  Adam Cohen  Nari Shin  Bruno Fusaro 《Sport Management Review》2018,21(2):160-175

While sport management scholars have explored inter-organizational partnerships and their associated challenges, they have devoted less attention to inter-organizational partnership development and sustainability in sport for development and peace (SDP), particularly across a wide range of organizations with varied missions and foci. Hence, the purpose of this qualitative study was to examine challenges faced by SDP organizations when forming and sustaining inter-organizational partnerships across contexts and partnership types, and to uncover strategies they have employed to overcome these challenges. Common challenges encountered across 29 SDP organizations included competition for resources, skepticism of sport as a development tool, unequal power relations, misaligned goals and mission drift, and implementation issues. Strategies included focusing on building relationships and networks, demonstrating benefits to partner, starting small then diversifying, keeping focused on mission and goals, involving partner, and treating the partnership as a business relationship. Theoretical extensions and practical implications are discussed, along with directions for future research.  相似文献   

Spontaneous change from seated to standing cycling position with increasing power is associated with a minimization of cost functions     

Antony Costes  Nicolas A Turpin  David Villeger  Pierre Moretto  Bruno Watier 《Journal of sports sciences》2018,36(8):907-913

Spontaneous changes of movement patterns may allow to elucidate which criteria influence movement pattern preferences. However, the factors explaining the sit-stand transition in cycling are unclear. This study investigated if biomechanical and/or muscle activation cost functions could predict the power at which the spontaneous sit-stand transition occurs. Twenty-five participants performed an incremental test leading to the sit-to-stand transition, and subsequent randomized pedaling trials at 20 to 120% of the transition power in seated and standing position. A Moment Cost Function based on lower limbs net joint moments and two Electromyographic Cost Functions based on EMG data were defined. All cost functions increased with increasing crank power (p < 0.001) but at different rates in the seated and standing positions. They had lower values in the seated position below the transition power and lower values in the standing position above the transition power (p < 0.05). These results suggest that spontaneous change of position observed in cycling with increasing crank power represents an optimal choice to minimize muscular efforts. These results support the use of simple cost functions to define optimal settings in cycling and to assess the cost of cycling during short-term efforts.  相似文献   

Effects of knowing the task duration on players’ pacing patterns during soccer small-sided games     

Ricardo Ferraz  Bruno Gonçalves  Roland Van Den Tillaar  Sergio Jiménez Sáiz  Jaime Sampaio  Mário C. Marques 《Journal of sports sciences》2018,36(1):116-122

The aim of this study was to identify the influence of prior knowledge of exercise duration on players’ pacing patterns during soccer small-sided games. Twenty semi-professional male soccer players participated in this study. In the first game scenario, players were not informed how long they would be required to play the small-sided game and the activity was terminated after 20 min (Unknown Condition). In the second game scenario, players were told that they would play the small-sided game for 10 min, but immediately after completing the 10-min game, they were asked to complete another 10 min (Partially Condition). In the third game scenario, players were instructed that they would play the small-sided game for 20 min and then they completed the 20-min game (Known Condition). The results presented a tendency of higher values in all performance variables in the [0′–10′] min compared with the [10′–20′] min. As the players’ previous knowledge about the tasks duration increased, the performance between two moments tended to be similar. Considering the entire 20-min game duration, the Partially Condition of the exercise was the most demanding condition. In conclusion, the knowledge of shorter durations of the exercise seems to lead to an increase of exercise duration demand, and longer exercise durations possibly tend to decrease differences between full knowledge and not knowing the exercise duration.  相似文献   

Book reviews     

Draper  James  Chopin  Bruno 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1985,30(3):377-382

International Review of Education -  相似文献   

Perception of humor by regular class students and students with learning disabilities or mild mental retardation   总被引：1，自引：0，他引：1  

R M Bruno  J M Johnson  J Simon 《Journal of learning disabilities》1987,20(9):568-570

  相似文献   

The Elliott Cresson medal     

Theodore L. Cairns  Robert H. Dickie  Bruno B. Rossi  A.J. Haagen-Smith 《Journal of The Franklin Institute》1975,299(5):367-376

This medal is awarded for discovery or original research adding to the sum of human knowledge, irrespective of commercial value; leading and practical utilizations of discovery; and invention, methods and products embodying substantial elements of leadership in their respective classes, or unsual skill or perfection in their workmanship.  相似文献   

The impact of M&A on the R&D process: An empirical analysis of the role of technological- and market-relatedness     

Bruno Cassiman  Massimo G. Colombo  Reinhilde Veugelers 《Research Policy》2005,34(2):195-220

Using information on 31 in-depth cases of individual M&A deals, we show that technological and market-relatedness between M&A partners distinctly affects the inputs, outputs, performance and organisational structure of the R&D process. While the findings in the literature on the effect of M&A on R&D are quite mixed, we can sharpen results by analysing data at the level of the R&D process. This comes at the price of a smaller sample and more qualitative data, for which caution in the interpretation is necessary. M&A between partners with ex-ante complementary technologies result in more active R&D performers after the M&A. In sharp contrast, when merged entities are technologically substitutive, they significantly decrease their R&D level after the M&A. Moreover, R&D efficiency increases more prominently when merged entities are technologically complementary than when they are substitutive. These two findings on the R&D level and the performance support the scope economy effect of M&A, on the one hand, and reject the scale economy effect of M&A, on the other. Next, for cases in which partners were active in the same technological fields before the M&A, the reduction of R&D is more prominent, while the R&D efficiency gain is smaller if merged entities were rivals in the product market prior to their merger than if they were non-rival. This suggests that rival firms reap little technology gains from mergers.  相似文献   

Can young students understand the mathematical concept of equality? A whole-year arithmetic teaching experiment in second grade     

Fischer  Jean-Paul  Sander  Emmanuel  Sensevy  Gérard  Vilette  Bruno  Richard  Jean-François 《European Journal of Psychology of Education - EJPE》2019,34(2):439-456

European Journal of Psychology of Education - Ensuring students correctly understand the notion of equality is a fundamental problem in teaching mathematics. Is it possible to teach arithmetic in...  相似文献