Cue usage in volleyball : a time course comparison of elite, intermediate and novice female players

This study compared visual search strategies in adult female volleyball players of three levels. Video clips of the attack of the opponent team were presented on a large screen and participants reacted to the final pass before the spike. Reaction time, response accuracy and eye movement patterns were measured. Elite players had the highest response accuracy (97.50 ± 3.5%) compared to the intermediate (91.50 ± 4.7%) and novice players (83.50 ± 17.6%; p<0.05). Novices had a remarkably high range of reaction time but no significant differences were found in comparison to the reaction time of elite and intermediate players. In general, the three groups showed similar gaze behaviour with the apparent use of visual pivots at moments of reception and final pass. This confirms the holistic model of image perception for volleyball and suggests that expert players extract more information from parafoveal regions

Miss Olympic Athlete? A Content Analysis of NBC’s Primetime Interviews During the 2016 Summer Olympic Games

The 2016 Summer Olympic Games in Rio de Janeiro has further exposed the difference in sports reporting between sexes. Creating social media controversy, viewers called out the sexist commentary directed towards women athletes emphasizing their relationship status, how many children they have, and male athlete accomplishments over the female’s athletic ability. This content analysis will dive deeper into NBC’s prime-time coverage of the twenty-third Olympiad, examining the sport and non-sport questions brought up during interviews with the male and female athletes. With reporters possessing more control over what is discussed on-air, when compared to live commentators, the goal of this analysis is to examine if a significant difference of sport-related themes remains between sexes, or if a few outliers are drawing disproportionate attention. No significant difference was found between questions asked during interviews with male and female athletes, however, there was a significant difference found between the mean number of non-sport questions posed by male reporters when compared to female reporters. Suggestions for future research are also explored

Movement recognition from wearable sensors data: power-aware evolutionary training for template matching and data annotation recovery methods

Human activities recognition finds numerous applications for example in sport training, patient rehabilitation, gait analysis and surgical skills evaluation. Wearable sensing and Template Matching Methods (TMMs) offer significant advantages compared to manual assessment methods as well as to more cumbersome camera-based setups and other machine learning (ML) algorithms. TMMs require less data for training than other ML methods, they are low-power and therefore suitable for integration on wearable sensor. They compute a sample-by-sample distance between two time series. When applied to gestures sensors data, this even enables a richer and more movement-specific assessment and feedback. However, TMMs lack of a standard training procedure. In this thesis, we introduce an innovative evolutionary training algorithm for TMMthat not only can maximize recognition performance, but it can also prefer power-minimisation by reducing the TMM’s computational cost with a configurable trade-off. We exhibit that a reduction is even possible without sacrificing recognition performance by exploiting the long-established concept of “time warping”. We demonstrate that our method is suitable for a wide variety of raw data as well as processed, fused and encoded sensor data. We present a new original multi-modal, multi-user dataset of beach volleyball movements that allowed to evaluate our training methods on a real-case of sport training actions. Moreover, the collection of this dataset helped to generate a set of guidelines for the collection of movement data in the wild, using wearable sensors. We introduce a 3D human model that can be animated through inertial wearable sensors data for troubleshooting, movement analysis and privacy-safe annotation of human activities. Finally, through a case study on a dataset of drinking actions, we demonstrate how TMM can improve the quality of a badly annotated but highly valuable dataset

Time Motion Analysis of Women\u27s Collegiate Indoor Volleyball

A better understanding of the demands of a sport can be determined by identifying work-to-rest ratios and frequency of high-intensity movements, but limited research has been on indoor volleyball. Video footage of two matches for a mid-level NCAA Division I women\u27s indoor volleyball team was analyzed using time motion analysis. Rally durations (mean of 7.6s), the rest times (mean of 18.8s), and the number of high-intensity movements (total of 1507) were recorded. The outside hitters, middle blockers, and setter performed the greatest number of HIM per rally with means of 0.78, 0.96 and 0.98 respectively and mean HIM/s of 0.031, 0.037, and 0.038 respectively. Total work and total time were calculated, 48.3 minutes and 166.5 minutes respectively. Therefore, the ball was only in play 29.0% of total time. The overall work-to-rest ratio was 0.40:1

Tapping the Full Potential? Jumping Performance of Volleyball Athletes in Game-Like Situations

Background: One key issue in elite interactive team sports is the simultaneous execution of motor actions (e.g., dribbling a ball) and perceptual-cognitive tasks (e.g., visually scanning the environment for action choices). In volleyball, one typical situation is to prepare and execute maximal block jumps after multiple-options decision-making and concurrent visual tracking of the ongoing game dynamics to find an optimal blocking location. Based on resource-related dual- and multi-tasking theories simultaneous execution of visual-cognitive and motor tasks may interfere with each other. Therefore, the aim of this study was to investigate whether volleyball-specific perceptual-cognitive demands (i.e., divided attention, decision making) affect blocking performance (i.e., jumping performance and length of the first step after the ready-block-position) compared to relatively isolated jumping performance.Methods: Twenty-two elite volleyball players (1st – 3rd German league) performed block jumps in front of a net construction in a single-task condition (ST) and in two perceptual (-cognitive) dual-task conditions including a dual-task low (DT_L; presenting a picture of an opponent attack on a screen) and a dual-task high condition (DT_H; presenting videos of an offensive volleyball set play with a two-alternative choice).Results: The results of repeated-measures ANOVAs showed a significant effect of conditions on jumping performance [F(2,42) = 33.64, p &lt; 0.001, ηp2 = 0.62] and on the length of the first step after the ready-block-position [F(2,42) = 7.90, p = 0.001, ηp2 = 0.27). Post hoc comparisons showed that jumping performance in DT_H (p &lt; 0.001) and DT_L (p &lt; 0.001) was significantly lower than in ST. Also, length of the first step after the ready-block-position in DT_H (p = 0.005) and DT_L (p = 0.028) was significantly shorter than in ST.Conclusion: Our findings suggest that blocking performance (i.e., jumping height, length of the first step) decreases in elite volleyball players when a perceptual (-cognitive) load is added. Based on the theory of Wickens (2002), this suggests a resource overlap between visual-processing demands for motor performance and for tracking the dynamics of the game. Interference with the consequence of dual-task related performance costs can therefore also be found in elite athletes in their specific motor expert domain

The Effect of Decision Training, from a Cognitive Perspective, on Decision-Making in Volleyball: A Systematic Review and Meta-Analysis

This article will be part of the Doctoral Thesis titled: “Study of cognitive skills in volleyball players in Spain and Brazil”, by Manuel Conejero Suárez, at the University of Extremadura. This work was conducted with thanks to the Fernando Valhondo Calaff Foundation for the contribution of predoctoral contracts to young researchers.Over the past few decades there has been great interest in the study of cognitive processes, and specifically decision-making, from a cognitive perspective. The aim of the present study was to systematically review the scientific literature on the effect of decision training interventions/programs, from a cognitive perspective, on the decision-making of volleyball players. The systematic search was carried out in five scientific electronic databases according to PRISMA guidelines Web of Science (WOS), Pubmed (Medline), Scopus, SportDiscus and Google Scholar. A total of eight studies met the inclusion criteria. The main finding of the meta-analysis was that the use of decision-making training programs/interventions led to significant improvements in volleyball players’ decision-making (Standardized mean difference = 0.94 with 95% confidence interval from 0.63 to 1.25), compared to normal active volleyball training. In addition, the heterogeneity of the interventions was low (I2 = 0%). From the results of the studies analyzed, we recommend using decisional interventions or training, both as part of normal active training or complementary to it, to improve the decision-making of the players, thus optimizing their ability to perceive and process relevant stimuli, and then generate quick and effective responses. These findings can be useful in the process of sports training

ENROLLMENT MANAGEMENT AND INTERCOLLEGIATE ATHLETICS: A STUDY OF WOMEN’S BEACH VOLLEYBALL

With college costs increasing annually and the number of high school students dropping in many areas of the country, enrollment management professionals must seek out creative strategies to appeal to a broader population of out-of-state students. This study assessed the impact of the three common faces of a holistic enrollment management plan: structural management, planning, and leadership, on the recruitment of out-of-state student-athletes to play NCAA Division I beach volleyball. Alternative explanations were explored to determine how an institution was successful in recruiting out-of-state beach volleyball student-athletes when the three common faces of a holistic enrollment management plan were not evident. Using a single significant case study approach, one institution was selected that stood out from their peers as being able to successfully recruit a high number of out-of-state student-athletes for their beach volleyball program. Interviews were conducted with three key stakeholders as the primary data collection method. A narrative inquiry methodology was used to analyze the data from the interviews, with the institution’s website and recruitment materials serving as supplemental material in order to allow the true essence of the story to emerge. Findings revealed that the institution did not demonstrate any of the three faces of a holistic enrollment management plan as limited collaboration was identified between the admissions office and the athletics department. The essence of this study indicates that extraordinary efforts from very dedicated individuals resulted in the successful recruitment of out-of-state student-athletes for a new or emerging sport. The results suggest that the institution would have even greater opportunity for success if they created strategic collaborative relationships across campus to facilitate the sharing of data and work together toward common recruitment goals. Advisor: Brent Cejd

Towards a More Efficient Training Process in High-Level Female Volleyball From a Match Analysis Intervention Program Based on the Constraint-Led Approach: The Voice of the Players

The aim of the research was to know the perception of high-level volleyball players of the changes produced (in relation to the previous season) in the efficiency of the training process, after a match analysis intervention program based on the Constraint-led Approach (CLA). The sample consisted of 11 players from a women’s volleyball team. The protocol of the intervention program consisted of providing objective, contextualised and systematic information to the coach (adapted to his needs) that would allow understanding the different real game contexts. We used semi-structured interviews to assess players’ perceptions. The athletes perceived changes in training, both in their preparation and development, specifically in greater involvement and organisation in preparing the training; in an increase in the specificity and suitability of training tasks according to individual needs; in the representativeness of the restrictions of the game; in a more tactical approach; in the variability of task and in the accountability to achieve the objective proposed. In addition, in the preparation and development for competition, the players detected more game planning; a deeper analysis of the opponents; an objective selection of the most relevant data, an increase in the depth of match analysis and the inclusion of the weekly meeting with the use of video compared to the previous season. These results expose the benefits of coaches incorporate programmes to obtain objective information about the game in their training process.Foundation Tatiana Pérez de Guzmán el BuenoConsejeria de Economia e Infraestructuras de la Junta de Extremadura (Spain) through the European Regional Development fund: A way to make Europe GR1812

A video-based framework for automatic 3d localization of multiple basketball players : a combinatorial optimization approach

Sports complexity must be investigated at competitions; therefore, non-invasive methods are essential. In this context, computer vision, image processing, and machine learning techniques can be useful in designing a non-invasive system for data acquisition that identifies players’ positions in official basketball matches. Here, we propose and evaluate a novel video-based framework to perform automatic 3D localization of multiple basketball players. The introduced framework comprises two parts. The first stage is player detection, which aims to identify players’ heads at the camera image level. This stage is based on background segmentation and on classification performed by an artificial neural network. The second stage is related to 3D reconstruction of the player positions from the images provided by the different cameras used in the acquisition. This task is tackled by formulating a constrained combinatorial optimization problem that minimizes the re-projection error while maximizing the number of detections in the formulated 3D localization problem8286CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPNão temNão temNão temWe would like to thank the CAPES, FAEPEX, FAPESP, and CNPq for funding their research. This paper has content from master degree’s dissertation previously published (Monezi, 2016) and available onlin