Warntjen, Andreas; Dowding, Keith
Veto players are political actors whose consent is necessary to adopt a new policy. Put otherwise, they have veto power which allows them to prevent a change to the status quo. The concept is crucial to the influential veto player theory developed by George Tsebelis. Building on earlier work in
Tychsen, Anders; McIlwain, D.; Brolund, T.
This paper presents the results of a comprehensive empirical study of the impact of integrating complex game characters in multi-player Role Playing Games across tabletop and digital formats. Players were provided with characters that had detailed background history, personality and goals. Player...
, categories and triggers involved in this process. By applying grounded theory to the analysis of the responses, a process-oriented player engagement framework was developed and four main components consisting of objectives, activities, accomplishments and affects as well as the corresponding categories...
Fallis, Todd L.
Discusses the process of introducing the trombone to beginning students and addresses the issue of warming-up. Provides resources for beginning trombone methods, band methods, and daily warm-up studies. Includes resources for scale studies and etudes for beginning to intermediate trombone players. (CMK)
Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad
Learning models of player behavior has been the focus of several studies. This work is motivated by better understanding of player behavior, a knowledge that can ultimately be employed to provide player-adapted or personalized content. In this paper, we propose the use of active learning for player...... experience modeling. We use a dataset from hundreds of players playing Infinite Mario Bros. as a case study and we employ the random forest method to learn mod- els of player experience through the active learning approach. The results obtained suggest that only part of the dataset (up to half the size...... that the method can be used online during the content generation process where the mod- els can improve and better content can be presented as the game is being played....
Vallgårda, Anna; Boer, Laurens; Cahill, Ben
In this design case we present the Hedonic Haptic Player—a wearable device that plays different patterns of vibrations on the body as a form of music for the skin. With this we begin to explore the enjoyability of vibrations in a wearable set-up. Instead of implementing vibrations as a haptic...... output for some form of communication we want to explore their hedonistic value. The process leading up to the Hedonic Haptic player served as a first step in getting a grasp of the design space of vibrotactile stimuli in a broader sense. This is reported as seven episodes of explorations. The Hedonic...
Sharples, Paul; Wilson, Scott; Popat, Kris; Griffiths, David; Beauvoir, Phillip
Sharples, Paul Wilson, S., Popat, K., Griffiths, D., Beauvoir, P. (2009) The Astro Learning Design Player. This software is distributed under the three clause BSD license, copyright TENCompetence Foundation
Florian Miftari; Juel Jarani; Dhimitraq Stratoberdha; Hazir Salihu
The purpose of this study was to compare the anthropometric measurement to the professional players of the three different disciplines of basketball, handball and volleyball. . For each player anthropometric measurements such as weight, body height, waist circumference, BMI and skinfold calculation on different sports are performed. Differences in terms of anthropometric measurements were assessed by independent static tests and the differences for each variable for each sport were evaluated ...
Full Text Available Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players dont have any preference in any stage of Stroop test. Chess players dont have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.
Nejati, Majid; Nejati, Vahid
Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST) data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players don't have any preference in any stage of Stroop test. Chess players don't have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.
Boone, Jan; Vaeyens, Roel; Steyaert, Adelheid; Vanden Bossche, Luc; Bourgois, Jan
The purpose of this study was to gain an insight into the physical and physiological profile of elite Belgian soccer players with specific regard to the player's position on the field. The sample consisted of 289 adult players from 6 different first division teams. The players were divided into 5 subgroups (goalkeepers, center backs, full backs, midfielders, and strikers) according to their self-reported best position on the field. The subjects performed anaerobic (10-m sprint, 5 × 10-m shuttle run [SR], squat jump [SJ], and countermovement jump [CMJ]) and aerobic (incremental running protocol) laboratory tests. The strikers had significantly shorter sprinting times (5-, 5- to 10-m time, and SR) compared with the midfielders, center backs, and goalkeepers, whereas the full backs were also significantly faster compared with the goalkeepers and the center backs. The goalkeepers and the center backs displayed higher jumping heights (total mean SJ = 40.7 ± 4.6 cm and CMJ = 43.1 ± 4.9 cm) compared with the other 3 positions, whereas the strikers also jumped higher than the full backs and the midfielders did. Regarding the aerobic performance, both full backs and the midfielders (61.2 ± 2.7 and 60.4 ± 2.8 ml · min(-1) · kg(-1), respectively) had a higher VO2max compared with the strikers, center backs, and goalkeepers (56.8 ± 3.1, 55.6 ± 3.5, and 52.1 ± 5.0 ml · min(-1) · kg(-1), respectively). From this study, it could be concluded that players in different positions have different physiological characteristics. The results of this study might provide useful insights for individualized conditional training programs for soccer players. Aside from the predominant technical and tactical skills, a physical profile that is well adjusted to the position on the field might enhance game performance.
Hichens, Michael; Drachen, Anders; Richards, Deborah
The player character is an important feature of many games, where it is through the character that the player interacts with game world. There has been considerable interest in the relationship between the player and the player character. Much of this work has examined the identification of players......, third) as an indication of the relationship between player and character. Results indicate that the presence of story and information about the player character had no effect on identification with the plater character. However, characteristics of the players, particularly gender and general experience...... in playing video games, did have a statistically significant affect, indicating that different levels of identification are more dependent on the player than on the game. This indicates that players are not a homogeneous group with respect to player character identification and is an important consideration...
While classically cryptography is concerned with the problem of private communication among two entities, say players, in modern cryptography multi-player protocols play an important role. And among these, it is probably fair to say that secret sharing, and its stronger version verifiable secret...... sharing (VSS), as well as multi-party computation (MPC) belong to the most appealing and/or useful ones. The former two are basic tools to achieve better robustness of cryptographic schemes against malfunction or misuse by “decentralizing” the security from one single to a whole group of individuals...... (captured by the term threshold cryptography). The latter allows—at least in principle—to execute any collaboration among a group of players in a secure way that guarantees the correctness of the outcome but simultaneously respects the privacy of the participants. In this work, we study three aspects...
This study aims to investigate whether different player-matching mechanisms in educational multi-player online games (MOGs) can affect students' learning performance, enjoyment perception and gaming behaviors. Based on the multi-player quiz game, TRIS-Q, developed by Tsai, Tsai and Lin (2015) using a free player-matching (FPM) mechanism, the same…
A sophisticated player is an individual who takes the action of the opponents, in a strategic situation, as determined by decision of rational opponents, and acts accordingly. A sophisticated agent is rational in the choice of his action, but ignores the fact that he is part of a strategic
Kelly M. Hastings
Full Text Available The NBA’s 1999 Collective Bargaining Agreement (CBA included provisions capping individual player pay in addition to team payrolls. This study examines the effect the NBA’s maximum player salary on player rents by comparing player pay from the 1997–1998 and 2003–2004 seasons while controlling for player productivity and other factors related to player pay. The results indicate a large increase in the pay received by teams’ second highest and, to a lesser extent, third highest paid players. We interpret this result as evidence that the adoption of the maximum player salary shifted rents from stars to complementary players. We also show that the 1999 CBA’s rookie contract provisions reduced salaries of early career players.
Þorsteinsson, Arnar Tumi; Lund, Henrik Hautop; Mastorakis, Nikos
With the creation of playware as intelligent hardware and software that creates play, it is possible to adapt the play tool to the individual user, and even to multiple users playing at the same time with the play tool. In this paper, we show how it is possible to implement adaptivity in modular...... to such differences, and argues that adaptivity is needed to make games fit to the individual users in both single-player games and multi-player games. As a case study, we implemented such adaptivity on modular interactive tiles for the single-user game ColorTimer, and for the multiple-user games PingPong, in which...
Ruiz‐Cotorro, A; Balius‐Matas, R; Estruch‐Massana, A; Angulo, J Vilaró
The general aetiology, diagnosis, and treatment of spondylolysis, a bone defect in the pars interarticularis of the vertebra, are reviewed. A retrospective study of young tennis players diagnosed between 2000 and 2004 with spondylolysis with or without spondylolisthesis, assessed by radiography and planar bone scintigraphy, is described. If the radiographic results were negative, computed tomography was performed. Sixty six cases were evaluated: 53 L5 lesions, eight L4 lesions, two L3 lesions, and one bilateral lesion at the L2 level. Two more lesions at two levels were found (bilateral L5 and unilateral L4 and L3 on the right side). Classification, treatment, and outcome of the cases are reported. A combination of radiography, planar bone scintigraphy, and SPECT is useful for evaluating spondylolysis in tennis players and recommending treatment. Use of a brace did not appear to achieve significant results. PMID:16632576
Alfonso Martínez Moreno
Full Text Available In the sport context, elite category, it is necessary to know all the factors, which in one way or another, affect the athletes throughout the different competitions. The object of study is to know the motivational profile of elite handball players. The sample consisted of 495 players, of whom 47.8% were boys and 52.2% girls, their ages ranged from 12 to 16 years, with an average of 13.8 years (dt = 1.0. Descriptive statistical analyzes of the sample, absolute and relative frequencies were performed for the qualitative variables and for the quantitative values minimum, maximum, mean, standard deviation, Cronbach's alpha. Correlation between variables, with the Pearson correlation coefficient. The MANCOVA test was performed to determine if there were differences between the dimensions of the questionnaire, according to age and years of practice. The results reveal that handball players elite category of the sample object of study have mainly intrinsic motivation, achieving high scores on general motivation, motivation achievement and motivation stimulation. In addition to moderately high values in introjected regulation and very low values in demotivation.
Szczepańska, Elzbieta; Spałkowska, Agnieszka
In sports, such as basketball and volleyball, players must demonstrate the speed, strength, stamina and concentration. Correct nutrition affects the strength of the muscles and the extension of capacity. It is also necessary for the proper functioning of the nervous system and determines the rate of regeneration after physical effort. The aim of this study was to assess dietary behaviours of professional volleyball and basketball players and compare the prevalence of correct behaviours in both groups. 209 professional volleyball and basketball players from sports clubs localized in six Silesian cities were survived with the mean of author questionnaire. The chi-square test was used to examine differences in the prevalence of the correct behaviours among players. Analysis of the results obtained showed that 52% of the players had 4-5 meals a day. 35% of respondents had wholemeal bread and/or groats daily. Milk and dairy products daily ate 71% of surveyed players, meat and sausages 70% respectively. 41% of respondents had cottage cheese and 28% had fish several times a week. Vegetables and fruit were eaten by 21% and respectively 23% of respondents. Sweets were eaten daily by 40% of surveyed, while fast-food were eaten several times a week by 17% of players. Nutrients for athletes were used by 32%, and vitamin supplementation by 48% of respondents. Prevalence of correct dietary behaviour in the group of professional volleyball and basketball players differed. Basketball players statistically more frequently than volleyball players had 4-5 meals a day, had wholemeal bread and/or thick groats, milk and dairy products, meat and sausages, especially poultry. They had raw vegetables and fruit several times a day. They drank more than 2.5 liters of fluids per day. They also significantly more frequently than volleyball players consumed the fast-food occasionally or never. Dietary behaviours of surveyed players were incorrect. Comparison of prevalence of proper behaviours
Fishman, Matthew P; Lombardo, Stephen J; Kharrazi, F Daniel
Vitamin D plays an important role in several systems of the human body. Various studies have linked vitamin D deficiency to stress and insufficiency fractures, muscle recovery and function, and athletic performance. The prevalence of vitamin D deficiency in the elite athletic population has not been extensively studied, and very few reports exist among professional athletes. There is a high prevalence of vitamin D deficiency or insufficiency among players attending the National Basketball Association (NBA) Combine. Cross-sectional study; Level of evidence, 3. This is a retrospective review of data previously collected as part of the routine medical evaluation of players in the NBA Combines from 2009 through 2013. Player parameters evaluated were height, weight, body mass index (BMI), and vitamin D level. Statistical analysis using t tests and analysis of variance was used to detect any correlation between the player parameters and vitamin D level. Vitamin D levels were categorized as deficient (32 ng/mL). After institutional review board approval was submitted to the NBA, the NBA released deidentified data on 279 players who participated in the combines from 2009 through 2013. There were 90 players (32.3%) who were deficient, 131 players (47.0%) who were insufficient, and 58 players (20.8%) who were sufficient. A total of 221 players (79.3%) were either vitamin D deficient or insufficient. Among all players included, the average vitamin D level was 25.6 ± 10.2 ng/mL. Among the players who were deficient, insufficient, and sufficient, the average vitamin D levels were 16.1 ± 2.1 ng/mL, 25.0 ± 3.4 ng/mL, and 41.6 ± 8.6 ng/mL, respectively. Player height and weight were significantly increased in vitamin D-sufficient players compared with players who were not sufficient (P = .0008 and .009, respectively). Player age and BMI did not significantly differ depending on vitamin D status (P = .15 and .77, respectively). There is a high prevalence of vitamin D deficiency
Title: Swimming literacy field hockey woman player ground. Objectives: To obtain and analyze data on the level ground swimming literacy field hockey woman player. Their perception swimming literacy for life, the use of non-specific regeneration and as a training resource. Methods: Analysis of scientific literature, survey, case study, data analysis and graphical presentation of results. Results of the work: field hockey player as swimming literate, benefits swimming but not used as a means of...
Yamaner, Faruk; Gumusdag, Hayrettin; Kartal, Alparslan; Gumus, M.; Gullu, A.; Imamoglu, O.
Study aim: To assess the prevalence and anatomical sites of injuries in professional soccer players in one game season. Material and methods: A cohort of 510 professional male soccer players consisting of 48 goalkeepers, 194 defence players, 189 mid-field players and 79 forward players of the 1st and 2nd Turkish Professional Soccer Leagues in…
Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona
Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert chess players using the Persian version of dichotic auditory-verbal memory test. The Persian version of dichotic auditory-verbal memory test was performed for 30 expert chess players aged 20-35 years and 30 non chess players who were matched by different conditions; the participants in both groups were randomly selected. The performance of the two groups was compared by independent samples t-test using SPSS version 21. The mean score of dichotic auditory-verbal memory test between the two groups, expert chess players and non-chess players, revealed a significant difference (p≤ 0.001). The difference between the ears scores for expert chess players (p= 0.023) and non-chess players (p= 0.013) was significant. Gender had no effect on the test results. Auditory memory function in expert chess players was significantly better compared to non-chess players. It seems that increased auditory memory function is related to strengthening cognitive performances due to playing chess for a long time.
Simkin, M V; Roychowdhury, V P
We investigate a pool of international chess title holders born between 1901 and 1943. Using Elo ratings, we compute for every player his expected score in a game with a randomly selected player from the pool. We use this figure as the player's merit. We measure players' fame as the number of Google hits. The correlation between fame and merit is 0.38. At the same time, the correlation between the logarithm of fame and merit is 0.61. This suggests that fame grows exponentially with merit.
Full Text Available In the context of globalisation and the current global financial crisis, new players are emerging in cooperation in Africa. These partners loosen financial constraints and conditionalities, increase the room for manoeuvre and stimulate commodity markets. On the other hand, they also increase the risks of renewed indebtedness and potentially weaken the coordination of aid policies. Do these partnerships call the new cooperation practices of OECD countries into question? Do they justify the return to a realpolitik or are they repeating the earlier mistakes of industrial powers? Can these mistakes be corrected? The question also arises as to whether the global crisis, which has a profound effect on Africa, will lead to a withdrawal or to a passing of the baton on to new, emerging powers. This article highlights the new geopolitical issues concerning Africa in a multipolar world, then discusses the new players involved in cooperation in Africa, before going on to explore the horizons that are opening up for cooperation in Africa, in particular with regard to the global crisis.
Odgaard, Peter Fogh; Stoustrup, Jakob; Andersen, Palle
a pair of residuals generated by Compact Disc Player. However, these residuals depend on the performance of position servos in the Compact Disc Player. In other publications of the same authors a pair of decoupled residuals is derived. However, the computation of these alternative residuals has been...
Odgaard, Peter Fogh; Wickerhauser, Mladen Victor
Optical disc players such as CD-players have problems playing certain discs with surface faults like scratches and fingerprints. The problem is to be found in the servo controller which positions the optical pick-up, such that the laser beam is focused on the information track. A scheme handling...
Full Text Available A two-player quantum game is considered in the presence of thermal decoherence. It is shown how the thermal environment modeled in terms of rigorous Davies approach affects payoffs of the players. The conditions for either beneficial or pernicious effect of decoherence are identified. The general considerations are exemplified by the quantum version of Prisoner Dilemma.
van Lankveld, G.; Spronck, P.H.M.; Bakkes, S.C.J.
Player behavioural modelling has grown from a means to improve the playing strength of computer programs that play classic games (e.g., chess), to a means for impacting the player experience and satisfaction in video games, as well as in cross-domain applications such as interactive storytelling. In
Cerynik, Douglas L; Lewullis, Gabriel E; Joves, Brian C; Palmer, Michael P; Tom, James A
Surgical treatment for chondral defects of the knee in competitive running and jumping athletes remains controversial. This study evaluated the performance outcomes of professional basketball players in the National Basketball Association (NBA) who underwent microfracture. Data from 24 professional basketball players from 1997 to 2006 was obtained and analyzed. NBA player efficiency ratings (PER) were calculated for two seasons before and after injury. A control group of 24 players was used for comparison. Study group and control group demographics including age, NBA experience, and minutes per game demonstrated no statistical difference. Mean time to return to an NBA game was 30.0 weeks from the time of surgery. The first season after returning to competition PER and minutes per game decreased by 3.5 (P 0.05) and 3.0 min (P NBA game. On return to competition player performance and minutes per game are diminished.
Full Text Available This study aims to introduce the method that can relieve vibrating forces to oral environment by making an embouchure aid. Thin plastic crown forms were fabricated to prevent tooth abrasion and irritation to lip mucosa for the saxophone player. After application to the player, the most comfort form was chosen and delivered to 3 professional saxophone players. After 5 mon, the players responded to the survey. This embouchure aid did not disturb playing and gave comfort to lower lip. In general, the players preferred thin soft type and thought it caused little effect on sound. Far too little attention has been paid to the problems encountered by single-reed wind instrumentalist who suffer from tooth abrasion and irritation to lip mucosa. The embouchure aid not only prevent tooth damage but also diminish the discomfort of tight embouchure.
Li, Lichun; Feron, Eric; Shamma, Jeff S.
the opponents' corresponding best responses depends only on the informed player's history action sequences. Moreover, efficient LP formulations to compute both player's security strategies are provided.
In asymmetric zero-sum games, one player has superior information about the game over the other. It is known that the informed players (maximizer) face the tradeoff of exploiting its superior information at the cost of revealing its superior information, but the basic point of the uninformed player (minimizer)\\'s decision making remains unknown. This paper studies the finite stage asymmetric repeated games from both players\\' viewpoints, and derives that not only security strategies but also the opponents\\' corresponding best responses depends only on the informed player\\'s history action sequences. Moreover, efficient LP formulations to compute both player\\'s security strategies are provided.
Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap
Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer. PMID:24632735
Full Text Available Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9, and forty-two age-matched amateur soccer players (mean age 11.8 in the age range 8 to 16 years performed a Stop Signal task (motor inhibition, the Attention Network Test (alerting, orienting, and executive attention and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer.
McNeill, L.; Jernigan, G.
When citizens become involved in the public policy decision-making process, who picks the players? Are there any criteria for determining which members of the public should sit at the table? These are questions frequently asked by new participants and observers of the public involvement process. In the interest of trust and credibility, the process must be one of self-selection. Any exclusion on the part of the sponsoring organization would probably be interpreted by the public and the press as manipulative self-interest. Clearly, at times there are irrational people attending public meetings or submitting written comments. But if an organization begins excluding participants, the risk increases that the process will be perceived as a travesty
Kawasaki, Takayuki; Ota, Chihiro; Yoneda, Takeshi; Maki, Nobukazu; Urayama, Shingo; Nagao, Masashi; Nagayama, Masataka; Kaketa, Takefumi; Takazawa, Yuji; Kaneko, Kazuo
A stinger is a type of neurapraxia of the cervical roots or brachial plexus and represents a reversible peripheral nerve injury. The incidence of and major risk factors for stingers among young rugby players remain uninvestigated. To investigate the incidence, symptoms, and intrinsic risk factors for stingers in elite rugby union teams of young players. Descriptive epidemiology study. A total of 569 male rugby players, including 358 players from 7 high school teams and 211 players from 2 university teams, were investigated using self-administered preseason and postseason questionnaires. The prevalence of a history of stingers was 33.9% (95% CI, 30.3-37.9), and 20.9% (119/569) of players experienced at least 1 episode of a stinger during the season (34.2 [95% CI, 26.2-42.1] events per 1000 player-hours of match exposure). The reinjury rate for stingers per season was 37.3% (95% CI, 30.4-44.2). Using the multivariate Poisson regression method, a history of stingers in the previous season and the grade and position of the player were found to be risk factors for stingers during the current season. The mean severity of injury was 2.9 days, with 79.3% (191/241) of the players not losing any time from playing after sustaining a stinger injury and 5.8% (14/241) of the players recovering within more than 14 days. The most frequent symptom was numbness in the unilateral upper extremity, and the most severe symptom was weakness of grasping (mean severity, 6 days). A logistic regression analysis indicated that a history of stingers in the previous season and an injury with more than 3 symptoms, especially motor weakness, were correlated with the severity of injury. Young rugby players with a history of stingers have a significantly high rate of repeat injuries. Although nearly 80% of the players experienced only minimal (0-1 day) time loss injuries, neurological deficits sometimes last beyond 1 month. A history of stingers was identified to be the strongest risk factor for
Comstock, R Dawn; Fields, Sarah K; Knox, Christy L
Our objective was to assess the prevalence of protective equipment use and the motivation for using protective equipment among a sample of US female rugby players. We surveyed a convenience sample of 234 current US female rugby players from 14 teams participating in a US women's rugby tournament, obtaining self-reported demographic, rugby exposure, and protective equipment use information. Mouthguards were the most commonly used piece of protective equipment: 90.8% of players reported having always worn a mouthguard while playing or practicing rugby within their most recent 3 months of play. Fewer than 15% of players reported having always worn other types of protective equipment. Equipment use varied by playing position. Whereas over 80% of players in all other positions always wore a mouthguard, 66.7% of scrum halves reported always wearing one. Both backs and forwards reported wearing shoulder pads, but only forwards reported always wearing padded headgear. Mouthguards, padded headgear, and shoulder pads were worn "to prevent injury," whereas ankle braces, neoprene sleeves, and athletic tape on joints were worn "to protect a current/recent injury." This is the first study of female rugby players to assess the prevalence of protective equipment use by playing position and the motivation for using protective equipment. With the exception of mouthguards, US female rugby players infrequently use protective equipment. Protective equipment use varies by playing position. Some types of protective equipment appear to be used as primary prevention mechanisms, whereas others are used as secondary or tertiary prevention mechanisms.
Shariff, A H; George, J; Ramlan, A A
The purpose of this study was to investigate the pattern of musculoskeletal injuries sustained by Malaysian badminton players. This is a retrospective case notes review of all badminton players who attended the National Sports Institute (NSI) Clinic, Kuala Lumpur, Malaysia, and were diagnosed with musculoskeletal injuries. In a two and a half year period, from January 2005 to June 2007, 469 musculoskeletal injuries were diagnosed among badminton players at the NSI Clinic. The mean age of the players who attended the clinic was 19.2 (range 13-52) years. Approximately 60 percent of the injuries occurred in players younger than 20 years of age. The majority of injuries (91.5 percent) were categorised as mild overuse injury and mostly involved the knee. The majority of the injuries sustained by badminton players in this study were due to overuse, primarily in the knee. The majority of the injuries were diagnosed in younger players and occurred during training/practice sessions. There was no difference in terms of incidence and types of injuries between the genders.
Shaker, Noor; Yannakakis, Georgios N.; Togelius, Julian
Generating immersive game content is one of the ultimate goals for a game designer. This goal can be achieved by realizing the fact that players’ perception of the same game differ according to a number of factors including: players’ personality, playing styles, expertise and culture background....... While one player might find the game immersive, others may quit playing as a result of encountering a seemingly insoluble problem. One promising avenue towards optimizing the gameplay experience for individual game players is to tailor player experience in real-time via automatic game content generation......-driven content generation....
Full Text Available Purpose. The aim of the study was to compare the morphological characteristics of experienced futsal players with professional soccer players. Methods. The research sample included 22 university futsal players and 22 professional soccer players. Parameters including body height and mass, skinfold thicknesses of the trunk and extremities, lower limb length, trunk width, humerus and femur bone breadths, and the circumferences of the chest, hips, thighs, and calves were used to calculate various somatic indices. Somatotyping was performed using the Heath–carter method. Differences in the characteristics between the futsal and soccer players were analyzed using Student’s t test. Intragroup analysis was also performed on futsal players depending on player position and compared with the arithmetic means and standard deviations of all variables of the entire sample. Results. compared with their soccer-playing peers, the futsal players were shorter, weighed less, had shorter lower limbs, narrower hips, and smaller hip circumference and bone breadth values. In contrast, higher levels of body fat and endomorphy were noted in this group. The proportion of mesomorphs and ectomorphs were similar in both groups. Futsal goalkeepers were differentiated by greater subcutaneous adiposity and body mass. Defenders had the slimmest body shape, with relatively narrower shoulders and hips, smaller bone breadths, and lower levels of adiposity. The body build of wingers was slightly larger. Pivoters were characterized by greater body height and larger values for the characteristics measuring the lateral trunk dimensions. Conclusions. The observed morphological differences between futsal and soccer players were mainly in body height and height-associated characteristics. This indicates that no specialized approach in futsal recruitment is currently used. This points to the need to develop a specialized approach in the player recruitment stage, as the tactical and
Wodarska, M; Witkoś, J; Drosdzol-Cop, A; Dąbrowska, J; Dąbrowska-Galas, M; Hartman, M; Plinta, R; Skrzypulec-Plinta, V
The aim of this study was to examine the relation between increased physical activity and menstrual disorders in adolescent female volleyball players. The study was conducted on 210 Polish female volleyball players, aged 13-17 years, the authorship questionnaire was used. The results of the study showed that irregular menstruation occurred in 19% of girls, spotting between menstrual periods in 27% and heavy menstruation was reported in 33% of girls. Out of all volleyball female players participating in the study, 94 girls (45%) declared absence of menstrual periods after regular cycles. Statistical analysis showed that the more training hours per week, the bigger probability of the occurrence of irregular menstruation. It was concluded that the number of hours of volleyball training per week affects regularity of menstrual cycles in female volleyball players. The absence of menstruation might be caused by the duration of training per week or years of training.
Eime, R; Finch, C; Sherman, C; Garnham, A
Methods: A survey of 303 players (aged ≥18 years) was conducted at three squash venues in Melbourne, Australia over a three week period in June 2000 to obtain information about protective eyewear use.
Kuriyama, Andrew M; Nakatsuka, Austin S; Yamamoto, Loren G
There is greater attention to head-related injuries and concussions in American football. The helmet's structural safety and the way that football players use their helmets are important in preventing head injuries. Current strategies include penalizing players for high-risk behavior such as leading with their helmet or hitting an opposing player above the shoulder. Passive strategies include helmet modification to better protect the head of the players or to change the playing style of the players. Hawai'i high school varsity football players were surveyed to determine how they use their helmets and how a new helmet design would affect their style of play. One hundred seventy-seven surveys were completed; 79% said that they used their helmet to hit an opposing player during a tackle and 46% said they made this contact intentionally. When asked about modifying helmets with a soft material on the outside, 48% said they thought putting a soft cover over a regular helmet would protect their head better. However, many participants said that putting a soft cover over their regular helmet was a bad idea for various reasons. Most young football players use their helmets to block or tackle despite being taught they would be penalized or potentially injured if they did so. By gaining a better understanding of why and how players use their helmets and how they would respond to new helmet designs, steps can be taken to reduce head injuries for all levels of play.
Dávila-Romero, C; Hernández-Mocholí, M A; García-Hermoso, A
This study is divided into three sequential stages: identification of fitness and game performance profiles (individual player performance), an assessment of the relationship between these profiles, and an assessment of the relationship between individual player profiles and team performance during play (in championship performance). The overall study sample comprised 525 (19 teams) female volleyball players aged 12-16 years and a subsample (N.=43) used to examine study aims one and two was selected from overall sample. Anthropometric, fitness and individual player performance (actual game) data were collected in the subsample. These data were analyzed through clustering methods, ANOVA and independence chi-square test. Then, we investigated whether the proportion of players with the highest individual player performance profile might predict a team's results in the championship. Cluster analysis identified three volleyball fitness profiles (high, medium, and low) and two individual player performance profiles (high and low). The results showed a relationship between both types of profile (fitness and individual player performance). Then, linear regression revealed a moderate relationship between the number of players with a high volleyball fitness profile and a team's results in the championship (R2=0.23). The current study findings may enable coaches and trainers to manage training programs more efficiently in order to obtain tailor-made training, identify volleyball-specific physical fitness training requirements and reach better results during competitions.
Leclere, Lance E; Asnis, Peter D; Griffith, Matthew H; Granito, David; Berkson, Eric M; Gill, Thomas J
Shoulder instability is a common problem in American football players entering the National Football League (NFL). Treatment options include nonoperative and surgical stabilization. This study evaluated how the method of treatment of pre-NFL shoulder instability affects the rate of recurrence and the time elapsed until recurrence in players on 1 NFL team. Retrospective cohort. Medical records from 1980 to 2008 for 1 NFL team were reviewed. There were 328 players included in the study who started their career on the team and remained on the team for at least 2 years (mean, 3.9 years; range, 2-14 years). The history of instability prior to entering the NFL and the method of treatment were collected. Data on the occurrence of instability while in the NFL were recorded to determine the rate and timing of recurrence. Thirty-one players (9.5%) had a history of instability prior to entering the NFL. Of the 297 players with no history of instability, 39 (13.1%) had a primary event at a mean of 18.4 ± 22.2 months (range, 0-102 months) after joining the team. In the group of players with prior instability treated with surgical stabilization, there was no statistical difference in the rate of recurrence (10.5%) or the timing to the instability episode (mean, 26 months) compared with players with no history of instability. Twelve players had shoulder instability treated nonoperatively prior to the NFL. Five of these players (41.7%) had recurrent instability at a mean of 4.4 ± 7.0 months (range, 0-16 months). The patients treated nonoperatively had a significantly higher rate of recurrence (P = 0.02) and an earlier time of recurrence (P = 0.04). The rate of contralateral instability was 25.8%, occurring at a mean of 8.6 months. Recurrent shoulder instability is more common in NFL players with a history of nonoperative treatment. Surgical stabilization appears to restore the rate and timing of instability to that of players with no prior history of instability.
Efforts to entice and retain player activity within a casino gaming environment require bringing to bear a range of sensory and physical influences. The challenge is to accomplish the operators’ objectives while at the same time ensuring any potential negative effects on the player are minimised. How casinos keep this in balance is at the heart of how the gaming floor works, and assessing such matters is becoming a necessary part of social responsibility.
Zhao, Dengji; Schiffel, Stephan; Thielscher, Michael
Research in General Game Playing aims at building systems that learn to play unknown games without human intervention. We contribute to this endeavour by generalising the established technique of decomposition from AI Planning to multi-player games. To this end, we present a method for the automatic decomposition of previously unknown games into independent subgames, and we show how a general game player can exploit a successful decomposition for game tree search.
Sortland, O.; Tysvaer, A.T.
Thirty-three former football players from the National Football Team of Norway were examined by cerebral computer tomography (CT). The CT studies, evaluated for brain atrophy, visually and by linear measurements compared two different normal materials. One third of the players were found to have central cerebral atrophy. It is concluded that the atrophy probably was caused by repeated small head injuries during the football play, mainly in connection with heading the ball. (orig.)
Basketball players are traditionally grouped into five distinct positions, but these designationsare quickly becoming outdated. We attempt to reclassify players into new groupsbased on personal performance in the 2016-2017 NBA regular season. Two dimensionalityreduction techniques, t-Distributed Stochastic Neighbor Embedding (t-SNE) and principalcomponent analysis (PCA), were employed to reduce 18 classic metrics down to two dimensionsfor visualization. k-means clustering discovered four grou...
Nitsche, Michael; Drake, Matthew; Murray, Janet
We suggest harvesting the power of multiplayer design to bridge content across different media platforms and develop player-driven cross-media experiences. This paper first argues to partially replace complex AI systems with multiplayer design strategies to provide the necessary level of flexibility in the content generation for cross-media applications. The second part describes one example project - the Next Generation Play (NGP) project - that illustrates one practical approach of such a player-driven cross-media content generation. NGP allows players to collect virtual items while watching a TV show. These items are re-used in a multiplayer casual game that automatically generates new game worlds based on the various collections of active players joining a game session. While the TV experience is designed for the single big screen, the game executes on multiple mobile phones. Design and technical implementation of the prototype are explained in more detail to clarify how players carry elements of television narratives into a non-linear handheld gaming experience. The system describes a practical way to create casual game adaptations based on players' personal preferences in a multi-user environment.
Wilson, Wayne J; O'Brien, Ian; Bradley, Andrew P
Among orchestral musicians, horn players are one of the most at-risk groups for noise-induced hearing loss (NIHL). To investigate this group further, pure tone audiometry and a 14-item questionnaire were used to assess the hearing health, as well as attitudes and practices regarding hearing conservation, among 142 French horn players attending an international horn conference in Brisbane, Australia. Of this study's French horn players, 11.1% to 22.2%, and 17.7% to 32.9% of those aged ≤40 years, showed some form of hearing loss (corrected for age and gender) typical of NIHL, using conservative versus lenient criteria, respectively. Stepwise multiple regression analyses showed no obvious predictor of hearing loss in this study's participants. Of the 18% of participants who reported using hearing protection, 81% used this protection "sometimes" and 50% used generic, foam, or other inferior forms of protection. Continued efforts to better manage the hearing health of horn players is warranted particularly as any hearing loss will affect a horn player's ability to perform and therefore his or her livelihood. Managing the hearing health of horn players will be challenging, however, with no simple predictor of NIHL loss being identified in this study's sample.
Chen, Zhengxing; Sun, Yizhou; El-nasr, Magy Seif; Nguyen, Truong-Huy D.
Successful analysis of player skills in video games has important impacts on the process of enhancing player experience without undermining their continuous skill development. Moreover, player skill analysis becomes more intriguing in team-based video games because such form of study can help discover useful factors in effective team formation. In this paper, we consider the problem of skill decomposition in MOBA (MultiPlayer Online Battle Arena) games, with the goal to understand what player...
Gajadhar, B.J.; Kort, de Y.A.W.; IJsselsteijn, W.A.
This article presents an empirical study of social setting as a determinant of player involvement in competitive play. We conceptualize player experience as comprising of components of involvement and enjoyment. Involvement relates to the attentional pull of games encompassing feelings of immersion,
Smith, Matthew V; Davis, Randi; Brophy, Robert H; Prather, Heidi; Garbutt, Jane; Wright, Rick W
There is a scarcity of literature evaluating injuries in youth fast-pitch softball players. To perform a descriptive analysis of player-reported injuries in youth fast-pitch softball position players and pitchers during a single select-level season. Prospective observation cohort study. Level 3. Ninety-eight athletes (48 pitchers, 50 position players) were followed for a single select fast-pitch softball season. Study participants completed web-based surveys every 3 weeks reporting injuries related to participation in fast-pitch softball. Injury was defined as pain causing cessation of participation in the current game or practice that prevents the player's return to that session or any pain that causes cessation of a player's customary participation on the day after the day of onset. The median age of the study participants was 14 years (range, 9-18 years). There were 49 reported injuries in 98 athletes. The average age was 13 years for those not injured and 14 years for those who were injured (P softball players. Better off-season and preseason conditioning may be a key factor for reducing pitching injuries. Recognition of injury patterns in fast-pitch softball players is critical to developing strategies to keep these athletes competing safely. © 2015 The Author(s).
Cieśla, E; Dutkiewicz, R; Mgłosiek, M; Nowak-Starz, G; Markowska, M; Jasiński, P; Dudek, J
Although physical activity brings a range of lifelong health benefits, it may also lead to injuries that pose a significant threat to health. It is particularly noticeable in people involved in professional sports where sport-related injuries commonly occur and are associated with intense exercise which aims to improve physical fitness. The article attempts to determine incidence of sports injuries reported by Plus League volleyball players, as well as to identify their most common types and causes. The research project involved 90 Plus League volleyball players aged 18-37 with the average age of 25.11 (SD±5.378). A method of diagnostic survey was applied to collect empirical data by means of questionnaire developed by the authors (researchers). The results were statistically analysed and verified with the analysis of variance (ANOVA) and χ2 test at the significance level (or critical P-value) of P≤0.05. Over 87% of the respondents suffered from at least one sport-related injury. In total, 362 injuries occurred, on average 4.02 injuries per one volleyball player. The most common sports injuries involved ankle or talocrural joint (46 injuries), knee and lower leg muscles (30), interphalangeal articulations of fingers (30) as well as shoulder joint. More than half of the injuries (57%) occurred twice or three times. Volleyball players commonly sustain injuries through contact with an opposing player in competition. Sport-specific injuries may also occur due to exhaustion, lack of rest and undertreated injuries. The most common volleyball-related injuries are primarily talocrural joint, hand and shoulder injuries. Common types of injuries that can affect volleyball players include muscles, joints and ligaments injuries, sprains and strains as well as bruises. Most of these injuries are caused by exhaustion, contact with an opposing player during competition and fatigue. The incidence of sport-related injuries seems to be influenced by such factors as somatic
Juan Del Coso
Full Text Available Background: Epidemiologic research to learn the incidence, type, location, and severity of female soccer injuries and the risk factors for sustaining a sport injury is the first step in developing preventive policies. The aim of this study was to analyze the incidence of injuries in the population of female soccer players in Spain. Methods: The injuries incurred by 25,397 female soccer players were registered by the medical staff of the Spanish Football Federation during 1 season. A standardized medical questionnaire was used to classify the injury according to type, severity, location, and injury mechanism. A total of 2108 injuries was reported with an incidence of 0.083 injuries per player per season. Most injuries were in the lower limbs (74.0%, mainly affecting knee (30.4% and ankle joints (17.9%. Results: The proportion of injuries derived from contact with another player was higher during matches (33.7% than during training (11.4%; p 0.05. Conclusion: Most female soccer injuries were located at the knee and ankle; the injury mechanism determined the playing time lost; and the player's age did not affect injury characteristics. Keywords: Ankle, Epidemiology, Knee, Sport injuries, Women
Missura, Olana; Gärtner, Thomas
In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.
Molik, Bartosz; Morgulec-Adamowicz, Natalia; Kosmol, Andrzej; Perkowski, Krzysztof; Bednarczuk, Grzegorz; Skowroński, Waldemar; Gomez, Miguel Angel; Koc, Krzysztof; Rutkowska, Izabela; Szyman, Robert J
Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg), body height (cm), the arm span (cm) and length of the body in the defensive position (cm). The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03) and the sum of good defense (p = 0.04). The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04), the sum of penalty defenses (p = 0.01), and fouls (p = 0.01). The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level. PMID:26834872
Full Text Available Goalball is a Paralympic sport exclusively for athletes who are visually impaired and blind. The aims of this study were twofold: to describe game performance of elite male goalball players based upon the degree of visual impairment, and to determine if game performance was related to anthropometric characteristics of elite male goalball players. The study sample consisted of 44 male goalball athletes. A total of 38 games were recorded during the Summer Paralympic Games in London 2012. Observations were reported using the Game Efficiency Sheet for Goalball. Additional anthropometric measurements included body mass (kg, body height (cm, the arm span (cm and length of the body in the defensive position (cm. The results differentiating both groups showed that the players with total blindness obtained higher means than the players with visual impairment for game indicators such as the sum of defense (p = 0.03 and the sum of good defense (p = 0.04. The players with visual impairment obtained higher results than those with total blindness for attack efficiency (p = 0.04, the sum of penalty defenses (p = 0.01, and fouls (p = 0.01. The study showed that athletes with blindness demonstrated higher game performance in defence. However, athletes with visual impairment presented higher efficiency in offensive actions. The analyses confirmed that body mass, body height, the arm span and length of the body in the defensive position did not differentiate players’ performance at the elite level.
Full Text Available The aim of the study was to test whether different levels of motivation are related to the injuries suffered by elite athletes. The sample consists of 80 professional handball players of ASOBAL League, with a mean age of 24.83 years (+ 5.21. Motivation was assessed through the CPRD scale (Gimeno, Buceta & Pérez-Llantada; 1999 and a self-report questionnaire was used to register sports injuries. The results indicate that there is a relationship between motivational levels and the risk for injury. Specifically, players with high motivated players had a greater number of moderate injuries. Although it may seem paradoxical, it is possible that an excessively high motivation leads to overachievement and risk behaviors, which in turn facilitate the appearance of lesions.
The CERN Cricket Club, having lost several key players, has had a very difficult season so far and is desperately in need of new players. Having qualified for the Cricket Switzerland semi-finals for the last two years (unfortunately losing both), this year we are bottom of the Western Pool, having played the last two league matches with only 10 players. If you are interested in playing cricket please join us at net practice, which takes place on the Prevessin site each Thursday evening from 18:00 to around 20:00 (weather permitting) or send me an e-mail (see below). Please have a look at the Cricket Club web site for more information: http://cern.ch/Club-Cricket/ Chris Onions, President of the CERN Cricket Club (firstname.lastname@example.org)
Larsen, Lasse Juel
on the subject matter from the catalogue of game theory. All four suggestions exclude the player from the relationship. This paper introduces a phenomenological point of view and includes the player in order to understand the relationship between structure and dressing. It argues that players constitute a bridge......This paper is a search for meaning or to be more precise a study of how meaning is produced between ontology and fiction in computer games. It sets out to investigate the relationship between formal abstract game structures and game representation (dressing) by presenting four suggestions...... or the center which establishes, upholds and renegotiate the relationship between formal game structure and game dressing. It also argues that players’ interaction with both structure and dressing produce meaning and the production of meaning is the relationship between formal abstract game structures and game...
Picardi, Andrea; Burelli, Paolo; Yannakakis, Georgios N.
industry and game AI research focus on the devel- opment of increasingly sophisticated systems to automate the control of the virtual camera integrating artificial intel- ligence algorithms within physical simulations. However, in both industry and academia little research has been carried out......In a three-dimensional virtual environment, aspects such as narrative and interaction largely depend on the placement and animation of the virtual camera. Therefore, virtual camera control plays a critical role in player experience and, thereby, in the overall quality of a computer game. Both game...... on the relationship between virtual camera, game-play and player behaviour. We run a game user experiment to shed some light on this relationship and identify relevant dif- ferences between camera behaviours through different game sessions, playing behaviours and player gaze patterns. Re- sults show that users can...
Bensoussan, A., E-mail: email@example.com [The University of Texas at Dallas, International Center for Decision and Risk Analysis, Jindal School of Management (United States); Chau, M. H. M., E-mail: firstname.lastname@example.org; Yam, S. C. P., E-mail: email@example.com [The Chinese University of Hong Kong, Department of Statistics (Hong Kong, People’s Republic of China) (China)
In this article, we consider mean field games between a dominating player and a group of representative agents, each of which acts similarly and also interacts with each other through a mean field term being substantially influenced by the dominating player. We first provide the general theory and discuss the necessary condition for the optimal controls and equilibrium condition by adopting adjoint equation approach. We then present a special case in the context of linear-quadratic framework, in which a necessary and sufficient condition can be asserted by stochastic maximum principle; we finally establish the sufficient condition that guarantees the unique existence of the equilibrium control. The proof of the convergence result of finite player game to mean field counterpart is provided in Appendix.
Generating immersive game content is one of the ultimate goals for a game designer. This goal can be achieved taken into account that players’ perceptions of the same game differ according to a number of factors including: players’ personality, playing styles, expertise and cultural background. One...... promising avenue towards optimizing the gameplay experience for individual game players - and thereby attempt to close the affective loop in games - is to automatically tailor the game content in real-time. To realize player-driven procedural content generation one needs to specify the aspects of the game...... that have a key influence on the gameplay experience, identify the relationship between these aspects and player experience and define a mechanism for tailoring the game content to each individual needs. In this dissertation we attempt to address the following research questions towards the aim...
Full Text Available In the provided research, some of the Big Data most prospective usage domains connect with distinguished player groups found in the business ecosystem. Literature analysis is used to identify the state of the art of Big Data related research in the major domains of its use-namely, individual marketing, health treatment, work opportunities, financial services, and security enforcement. System theory was used to identify business ecosystem major player types disrupted by Big Data: individuals, small and mid-sized enterprises, large organizations, information providers, and regulators. Relationships between the domains and players were explained through new Big Data opportunities and threats and by players’ responsive strategies. System dynamics was used to visualize relationships in the provided model.
Reed, Nick; Taha, Tim; Greenwald, Richard; Keightley, Michelle
Despite the growing popularity of ice hockey among female youth and interest in the biomechanics of head impacts in sport, the head impacts sustained by this population have yet to be characterized. To describe the number of, biomechanical characteristics of, and exposure to head impacts of female youth ice hockey players during competition and to investigate the influences of player and game characteristics on head impacts. Cohort study. Twenty-seven female youth ice hockey players (mean age = 12.5 ± 0.52 years) wore instrumented ice hockey helmets during 66 ice hockey games over a 3-year period. Data specific to player, game, and biomechanical head impact characteristics were recorded. A multiple regression analysis identified factors most associated with head impacts of greater frequency and severity. A total of 436 total head impacts were sustained during 6924 minutes of active ice hockey participation (0.9 ± 0.6 impacts per player per game; range, 0-2.1). A higher body mass index (BMI) significantly predicted a higher number of head impacts sustained per game (P = .008). Linear acceleration of head impacts was greater in older players and those who played the forward position, had a greater BMI, and spent more time on the ice (P = .008), whereas greater rotational acceleration was present in older players who had a greater BMI and played the forward position (P = .008). During tournament games, increased ice time predicted increased severity of head impacts (P = .03). This study reveals for the first time that head impacts are occurring in female youth ice hockey players, albeit at a lower rate and severity than in male youth ice hockey players, despite the lack of intentional body checking.
Carson, F.; Polman, Remco C.J.
Background The aim of the present study was to explore the views of professional rugby union players during the early rehabilitation, late rehabilitation and return to play stages, following anterior cruciate ligament (ACL) injury. Methods A qualitative dominant, mixed methodological approach was utilized with five players who had suffered an ACL injury requiring reconstructive surgery. A longitudinal approach, concurrent with each player?s rehabilitation, consisting of twice monthly intervie...
Title: Effect of coach change on professional tennis players Objectives of work: The aim of the thesis is to analyze the impact of coach change on professional tennis players from the psychology perspective, social relationship and player's attitude to the sport itself. The impact of the coach change on player's approach to tennis, game results, personal life and interpersonal relationships will be examined. Method: The methods that will be used are narrative interviews - annotated transcript...
Dobrosielski, Devon A.; Rosenbaum, Daryl; Wooster, Benjamin M.; Merrill, Michael; Swanson, John; Moore, J. Brian; Brubaker, Peter H.
Collegiate American football players may be at risk for cardiovascular disease. Objective: To compare cardiovascular disease risk factors and cardiovascular structure and function parameters of football players, stratified by position, to a group of sedentary, nonathletes. Participants: Twenty-six collegiate football players and 13 nonathletes…
This study focused on coping strategies used by soccer (football) players by exploring the role of the environment, ethnicity and culture in players' response to stressful situations. An interpretive-qualitative research methodology was applied with a sample of 33 professional soccer players. The subjects were representative ...
Chiang, Yu-Tzu; Lin, Sunny S. J.; Cheng, Chao-Yang; Liu, Eric Zhi-Feng
The authors conducted two studies to explore online game players' flow experiences and positive affect. Our findings indicated that online game are capable of evoking flow experiences and positive affect, and games of violent or nonviolent type may not arouse players' aggression. The players could be placed into four flow conditions: flow,…
Broodryk, Retief; van den Berg, Pieter Hendrick
The aims of this study were firstly to determine the players' perceptions of their respective coaches' coaching effectiveness and secondly, determine the difference between big and small schools of the players' perceptions of their respective coaches' coaching effectiveness. Four hundred and seventy six players from 22 schools were asked to fill…
The physique of rugby players has evolved over the course of the Twentieth Century. A novel morphological dataset was constructed of all Springbok rugby players until 2014. Although most of the change in body structure, particularly body weight, occurs during the era of professionalism, white Springbok rugby players ...
The aim of this study was to analyze technical drills, warm-up and cool-down exercises used by wheelchair basketball players of the Turkish league in relation to training sessions. 33 male wheelchair basketball players participated in the study (mean age 26.6[plus or minus]5,95 years). All players reported that they used warm-up exercises before…
Football is the most popular sport in the world. Foot morphology and foot preference are important factors in football player's performance. The aim of this cross-sectional study was to evaluate the foot morphology of elite football players with different foot preferences. 407 male football players participated in this study. 328 of ...
van Beijsterveldt, A.M.C.
Soccer causes the largest number of injuries each year (18% of all sports injuries) in the Netherlands. The aim of this dissertation is to contribute to the body of evidence on injury prevention for adult male soccer players. Chapter 1 is a general introduction and presents the “sequence of
This article reviews all the players of the photovoltaic industry in France (silicon producers, electrical component manufacturers, solar system manufacturers, design offices, solar system wholesalers, installers, and solar farm operators). For each company the following is reported: name, activity sector, historical background, staff, turnover, achievement and projects. (A.C.)
Full Text Available Objective: In this work the anthropometric features and the body composition of Italian hockey players, members of the Female National team, were analysed. The purpose of the research was to verify if morphological features could influence the performance of different positional groups. Materials and Methods: Each player was measured for her total and sitting height, weight, 9 skinfolds thickness and bioelectrical impedance analysis. Different equations were used to calculate the Fat% from skinfolds thickness. Results: Average height is not a crucial advantage for this sport. On the contrary the proportion trunk-limb seems to play an important role for the performance of the midfield players. Percentage of body fat of the hockey players was lower than the Fat% of the non-athletes women of the same age. Significant differences were found between Fat% determined by skinfolds thickness and Fat% obtained by bioelectrical impedance analysis. Conclusions: The results of this study indicate that there are significant differences in anthropometric features and in body composition between positional groups, stressing the importance of a specific training program. Keywords: field hockey, bioelectrical impedance, skinfolds thickness, anthropometry.
Eime, R M; Finch, C F; Sherman, C A; Garnham, A P
To determine factors associated with adult squash players' protective eyewear behaviours. A survey of 303 players (aged >or =18 years) was conducted at three squash venues in Melbourne, Australia over a three week period in June 2000 to obtain information about protective eyewear use. Of 303 participants the response rate was 98.1%; 66.1% were males, with a mean age of 40.5 years. The majority (68.4%) had played squash for 10 years or more. Although 18.8% of players reported using protective eyewear, only 8.9% reported wearing approved eyewear. Both age group (peye injuries (50.0%) and knowledge of eye injury risk (33.9%). A commonly reported barrier was restriction of vision (34.2%). These findings demonstrate a low prevalence of voluntary use of appropriate protective eyewear. Future prevention strategies incorporating education campaigns should focus on increasing players' knowledge of risks. The barriers to use and misconceptions about which types of eyewear is most protective need to be addressed as a priority.
Webb, J; Bannister, G
In a random sample of 105 first class rugby players, 45% gave a history of injury of the acromioclavicular joint. All continued to play at the highest level. The effects of the injury appeared to be minimal. Supraspinatus impingement syndrome commonly associated with acromioclavicular pathology was sought, but not found.
Maria Abella del Campo
Full Text Available Introduction: Basketball is a sport with a high heterogeneity anthropometric as playing position. Point guard is usually the lowest player but also the fastest. Guard is similar to point guard, faster and more agile than the others. Small forward has an intermediate height between the inside and outside players and it combines height with velocity. And center (pivot has a physical role, it has the highest and more muscle mass. The aim of this study is to describe the kinanthropometric profile of male cadet “Valencia Basket Club”. Material and Methods: A total of 20 male cadet basketball players were evaluated (15.35±0.59 years old. An anthropometrist level 1 took anthropometric measures according to the methodology of the International Society for the Advancement of Kinanthropometry (ISAK. Body composition was calculated according to the kinanthropometry consensus of the Kinanthropometry Spanish Group (GREC, somatotype with Heath-Carter’s method and adiposemuscular and cardiovascular risk index. Results: Differences in values of weight, height, skinfold and body composition from variables of sample and position were observed. Lower values were from point guard position and higher values were from center position. An increasing trend of these parameters was established in the following order: point guard, guard, small forward and center. Conclusions: The Valencia Basket Club cadet player overall somatotype is balance ectomorph. To know kinanthropometric profile may be beneficial to develop specific training and nutrition plans as well as to see evolution and characteristics for optimal performance
Full Text Available Purpose: to determine the model indicators of technical and tactical actions in the attack highly skilled volleyball players. Material and Methods: the study used statistical data of major international competitions: Olympic Games – 2012 World Championships – 2010, World League – 2010–2014 European Championship – 2010–2014. A total of 130 analyzed games. Methods were used: analysis and generalization of scientific and methodological literature, analysis of competitive activity highly skilled volleyball players, teacher observation, modeling technical and tactical actions in attacking highly skilled volleyball players. Results: it was found that the largest volume application of technical and tactical actions in the attack belongs to the group tactics «supple movement», whose indicator is 21,3%. The smallest amount of application belongs to the group tactics «flight level» model whose indicators is 5,4%, the efficiency of 3,4%, respectively. It is found that the power service in the jump from model parameters used in 51,6% of cases, the planning targets – 21,7% and 4,4% planning to reduce. Attacks performed with the back line, on model parameters used in the amount of 20,8% efficiency –13,7%. Conclusions: we prove that the performance of technical and tactical actions in the attack can be used as model in the control system of training and competitive process highly skilled volleyball players
This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives.......This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives....
This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives.......This article gives insights into why and how football brands (e.g. clubs and governing bodies) can benefit from enhancing the activation of players in football management and football marketing initiatives....
Kerr, Zachary Y; Collins, Christy L; Mihalik, Jason P; Marshall, Stephen W; Guskiewicz, Kevin M; Comstock, R Dawn
Little research has examined concussion outcomes in terms of impact location (ie, the area on the head in which the impact occurred). This study describes the epidemiology of concussions resulting from player-to-player collision in high school football by impact location. National High School Sports-Related Injury Surveillance Study data (2008/2009-2012/2013) were analyzed to calculate rates and describe circumstances of football concussion (eg, symptomology, symptom resolution time, return to play) resulting from player-to-player collisions by impact location (ie, front-, back-, side-, and top-of-the-head). Most concussions resulting from player-to-player collisions occurred from front-of-the-head (44.7%) and side-of-the-head (22.3%) impacts. Number of symptoms reported, prevalence of reported symptoms, symptom resolution time, and length of time to return to play were not associated with impact location. However, a larger proportion of football players sustaining concussions from top-of-the-head impacts experienced loss of consciousness (8.0%) than those sustaining concussions from impacts to other areas of the head (3.5%) (injury proportion ratio 2.3; 95% confidence interval 1.2-4.2; P = .008). Players had their head down at the time of impact in a higher proportion of concussions caused by top-of-the-head impacts (86.4%) than concussions from impacts to other areas of the head (24.0%) (injury proportion ratio 3.6; 95% confidence interval 3.2-4.0; P impact location. Recommended strategies for reducing the proportion of top-of-the-head impacts include improved education regarding tackling with proper "head-up" technique. Copyright © 2014 by the American Academy of Pediatrics.
Hänggi, Jürgen; Brütsch, Karin; Siegel, Adrian M; Jäncke, Lutz
The game of chess can be seen as a typical example for an expertise task requiring domain-specific training and experience. Despite intensive behavioural studies the neural underpinnings of chess performance and expertise are not entirely understood. A few functional neuroimaging studies have shown that expert chess players recruit different psychological functions and activate different brain areas while they are engaged in chess-related activities. Based on this functional literature, we predicted to find morphological differences in a network comprised by parietal and frontal areas and especially the occipito-temporal junction (OTJ), fusiform gyrus, and caudate nucleus. Twenty expert chess players and 20 control subjects were investigated using voxel-based and surface-based morphometry as well as diffusion tensor imaging. Grey matter volume and cortical thickness were reduced in chess players compared with those of control men in the OTJ and precunei. The volumes of both caudate nuclei were not different between groups, but correlated inversely with the years of chess playing experience. Mean diffusivity was increased in chess players compared with that of controls in the left superior longitudinal fasciculus and the Elo score (a chess tournament ranking) was inversely related to mean diffusivity within the right superior longitudinal fasciculus. To the best of our knowledge we showed for the first time that there are specific differences in grey and white matter morphology between chess players and control subjects in brain regions associated with cognitive functions important for playing chess. Whether these anatomical alterations are the cause or consequence of the intensive and long-term chess training and practice remains to be shown in future studies. Copyright © 2014 Elsevier Ltd. All rights reserved.
Gibson, Claire; Hindle, Chloe; McLay-Cooke, Rebecca; Slater, Joanne; Brown, Rachel; Smith, Brett; Baker, Dane; Healey, Philip; Black, Katherine
There is limited information on the risk of eating disorders and body image of elite male athletes. However, research suggests there are some athletes who have poor body image and they may be at increased risk of developing eating disorders. Therefore, the current study investigated risk of eating disorders, body image, and the relationship with age, in elite rugby union players during their pre-season training period.This cross-sectional study was undertaken at the start of the pre-season amongst elite rugby union players in New Zealand. Twenty-six professional rugby union players completed a 49-item questionnaire on body image and disordered eating. A 'body image score' was calculated from questionnaire subscales including 'drive for thinness', 'bulimia' and 'body dissatisfaction', with total scores above twenty indicative of poor body image.Body image scores varied from 8-39 out of a possible 0-100. Disordered eating behaviours were reported, including binge eating at least once a week (15%, n=4/26), pathogenic weight control use (4%, n=1/26) and avoidance of certain foods (77%, n=20/26). There was a statistically significant inverse association between the bulimia subscale and age (P = 0.034).At the start of the pre-season training period, many elite rugby union players experience disturbances in body image. The prevalence of disordered eating behaviours is of concern, and needs to be minimised due to the negative impact on health and performance. A focus on assessment and education of younger male rugby players may be required in order to reduce disordered eating patterns.
Soccer is one of the most popular sports in the world. There is still much uncertainty and debate surrounding its physiological requirements because emphasis is on skills to the neglect of fitness, conservative training methods and the difficulty of studying the sport scientifically. The frequently found values for total distance covered in a game of about 10 km and an above-average, though not outstanding, maximum oxygen uptake of 60 ml/kg/min suggest a moderate overall aerobic demand. A comparison of top teams and players with less able participants indicates that the components of anaerobic fitness-speed, power, strength and the capacity of the lactic acid system may differentiate better between the 2 groups. Generally, there is a reduction in the level of activity in the second half of games compared with the first. There is some evidence that increased aerobic fitness may help counteract this. Progressively lower muscle glycogen stores are one likely cause of reduction in activity, and nutrition also appears to be a key factor in minimising performance deterioration, both in terms of overall diet and, more particularly, the ingestion of carbohydrates immediately before, during and after a game. There are evolutionary trends in the sport such as greater frequency of games, changes in the roles of players, and new strategies and tactics which are placing increasing demands on the all-round fitness of players. Many studies indicate scope for improvement in player fitness. The challenge for coaches and players is to meet these fitness requirements without sacrificing the skill work which makes the sport unique.
Smith, Matthew V.; Davis, Randi; Brophy, Robert H.; Prather, Heidi; Garbutt, Jane; Wright, Rick W.
Background: There is a scarcity of literature evaluating injuries in youth fast-pitch softball players. Purpose: To perform a descriptive analysis of player-reported injuries in youth fast-pitch softball position players and pitchers during a single select-level season. Study Design: Prospective observation cohort study. Level of Evidence: Level 3. Methods: Ninety-eight athletes (48 pitchers, 50 position players) were followed for a single select fast-pitch softball season. Study participants completed web-based surveys every 3 weeks reporting injuries related to participation in fast-pitch softball. Injury was defined as pain causing cessation of participation in the current game or practice that prevents the player’s return to that session or any pain that causes cessation of a player’s customary participation on the day after the day of onset. Results: The median age of the study participants was 14 years (range, 9-18 years). There were 49 reported injuries in 98 athletes. The average age was 13 years for those not injured and 14 years for those who were injured (P softball players. Better off-season and preseason conditioning may be a key factor for reducing pitching injuries. Clinical Relevance: Recognition of injury patterns in fast-pitch softball players is critical to developing strategies to keep these athletes competing safely. PMID:26502442
Pastor, M F; Ezechieli, M; Classen, L; Kieffer, O; Miltner, O
The volleyball game has a high complexity and thus entails a lot of strain to the players. Due to this high and different training and competition strain comprehensive and individual training plans should be developed with competing training objectives in order to prevent injuries. The aim of the study was to analyse prospectively over six seasons the acute and overuse injuries of a German male professional volleyball team. The study included 34 male national league players from season the 2007/08 to 2012/13. All players received a sport medicine examination and a functional diagnosis before each season. Based on the results the players received an individual training plan. The players suffered 186 injuries. The prevalence of acute injuries was 1.94 per player and overuse injuries 0.64 per player. The incidence of acute injuries was 3.3/1000 h volleyball and overuse injuries 1.08/1000 h volleyball. The largest number of injuries was found in the spine. The players had most likely minor injuries. The players had significantly fewer injuries in their second season (1.92) than in their first season (3.25; p= 0.004). It could be concluded that volleyball is a sport with a relative low prevalence of injuries compared to other team sports. The prevalence of injury is 2.58 per player. Due to an injury a player dropped out 16.91 days per season. An individual training program seems to reduce the incidence of injury.
Aarseth, Espen J.
This paper is an attempt to understand Game Studies through the contested notion of the “player” both inside and outside “the game object” – that is the object that game users perceive and respond to when they play. Building on Hans-Georg Gadamer’s notion of games as a subject that “masters...... the players”, the paper will go beyond the traditional split between the social sciences’ real players and the aesthetics/humanities critical author-as-player, and present a theory of the player and player studies that incorporates the complex tensions between the real, historical player and the game’s human...... components. Since games are both aesthetic and social phenomena, a theory of the player must combine both social and aesthetic perspectives to be successful. The tension between the humanities and the social sciences over who controls the idea of the player can be found mirrored also in the struggle between...
Grgantov, Zoran; Milić, Mirjana; Katić, Ratko
With the purpose of determining the factor structure of explosive power, as well as the influence of each factor on situational efficiency, 56 young female volleyball players were tested using 14 tests for assessing nonspecific and specific explosive power. By factor analysis, 4 significant factors were isolated which explained the total of over 80% of the common variability in young female volleyball players. The first factor was defined as volleyball-specific jumping, the second factor as nonspecific jumping and sprinting, the third factor as throwing explosive power, while the fourth factor was interpreted as volleyball-specific throwing and spiking speed from the ground. Results obtained by regression analysis in the latent space of explosive power indicate that the identified factors are good predictors of player quality in young female volleyball players. The fourth factor defined as throwing and spiking speed from the ground had the largest influence on player quality, followed by volleyball-specific jumping and nonspecific jumping and sprinting, and to a much lesser extent, by throwing explosive power The results obtained in this age group bring to the fore the ability of spiking and serving a ball of high speed, which hinders the opponents from playing those balls in serve reception and field defence. This ability, combined with a high standing vertical jump reach and spike approach vertical jump reach (which is the basis of the 1st varimax factor) enables successful performance of all volleyball elements by which points are won in complex 1 (spike) and complex 2 (serve and block). Even though the 2nd factor (nonspecific jumping and sprinting) has a slightly smaller impact on situational efficiency in young players, this ability provides preconditions i.e. preparation for successful realisation of all volleyball elements, so greater attention must be paid to perfecting it in young female volleyball players.
Boden, Lauren M; Rosengren, Kenneth J; Martin, Daniel F; Boden, Scott D
Although many aspects of vision have been investigated in professional baseball players, few studies have been performed in developing athletes. The issue of whether youth baseball players have superior stereopsis to nonplayers has not been addressed specifically. The purpose of this study was to determine if youth baseball/softball players have better stereo acuity than non-ball players. Informed consent was obtained from 51 baseball/softball players and 52 non-ball players (ages 10 to 18 years). Subjects completed a questionnaire, and their static near stereo acuity was measured using the Randot Stereotest (Stereo Optical Company, Chicago, Illinois). Stereo acuity was measured as the seconds of arc between the last pair of images correctly distinguished by the subject. The mean stereo acuity score was 25.5 +/- 1.7 seconds of arc in the baseball/softball players and 56.2 +/- 8.4 seconds of arc in the non-ball players. This difference was statistically significant (P softball players had significantly better static stereo acuity than non-ball players, comparable to professional ball players.
Christian Wisdom Magtajas Valleser
Full Text Available The purpose of this study is to determine the common injuries of Filipino collegiate tennis players; 110 varsity tennis players with a mean of 20 years old (SD ± 1.7 with an average playing experience of 12 years participated in the study. There was a 100% occurrence of at least one injury with an average rate of 5.98 injuries per person. The authors observed that the most commonly injured anatomical region is the lower extremity; ankles were recorded as the most commonly injured part. Other commonly injured areas included the shoulders and lower back. Furthermore, the most common injury type is tendinitis, sprains, and strains. The recorded injuries were mostly associated with overuse injuries, and the findings were similar to those of most other studies on tennis injuries. A larger sample size may provide more conclusive findings on tennis injuries, particularly in different levels of competition, such as recreational or professional athletes.
Bohl, Katrin; Hummert, Sabine; Werner, Sarah; Basanta, David; Deutsch, Andreas; Schuster, Stefan; Theissen, Günter; Schroeter, Anja
In this and an accompanying paper we review the use of game theoretical concepts in cell biology and molecular biology. This review focuses on the subcellular level by considering viruses, genes, and molecules as players. We discuss in which way catalytic RNA can be treated by game theory. Moreover, genes can compete for success in replication and can have different strategies in interactions with other genetic elements. Also transposable elements, or "jumping genes", can act as players because they usually bear different traits or strategies. Viruses compete in the case of co-infecting a host cell. Proteins interact in a game theoretical sense when forming heterodimers. Finally, we describe how the Shapley value can be applied to enzymes in metabolic pathways. We show that game theory can be successfully applied to describe and analyse scenarios at the molecular level resulting in counterintuitive conclusions.
Hadiji, Fabian; Sifa, Rafet; Drachen, Anders
Free-to-Play or "freemium" games represent a fundamental shift in the business models of the game industry, facilitated by the increasing use of online distribution platforms and the introduction of increasingly powerful mobile platforms. The ability of a game development company to analyze...... a crucial value, allowing developers to obtain data-driven insights to inform design, development and marketing strategies. One of the key challenges is modeling and predicting player churn. This paper presents the first cross-game study of churn prediction in Free-to-Play games. Churn in games is discussed...... and derive insights from behavioral telemetry is crucial to the success of these games which rely on in-game purchases and in-game advertising to generate revenue, and for the Company to remain competitive in a global marketplace. The ability to model, understand and predict future player behavior has...
Hammershøi, Dorte; Ordoñez, Rodrigo Pizarro; Reuter, Karen
The technological development within personal stereo systems,such as MP3 players, e. g. iPods, has changed music listening habits from home entertainment to everyday and everywhere use. The technology has developed considerably, since the introduction of cassette players and CD walkmen. High......-level low-distortion music is produced by minimal devices which can play for long periods. In this paper, the existing literature on effects of personal stereo systems is reviewed, incl. studies of exposure levels, and effects on hearing. Generally, it is found that the levels being used are of concern......, which in one study is demonstrated to relate to the specific use in situations with high levels of background noise. Another study demonstrates that the effect of using personal stereo is comparable to that of being exposed to noise in industry. The results are discussed in view of the measurement...
Magnussen, Rikke; Misfeldt, Morten
transformed the game to accommodate social interaction. With these transformed ways of playing the game, they managed to get to the top of the high score list while avoiding the educational parts of the game. Players transforming educational games to escape learning elements can be a problem when these games...... are used for formal education. In this paper we argue that player transformation of educational games can, however, be the basis of exciting and unconventional learning of valuable things, such as how to transform information technology to better accommodate social interaction.......Children's great interest in multiplayer games has led to attempts to design educational multiplayer games. In this study, we have studied a test of an educational multiplayer game designed for mathematics education for children aged nine to twelve. In our observations, it became clear that pupils...
Full Text Available This paper presents an ontology that leads the player of a serious game - regarding conflict handling - to the educative experience from which they will benefit the most. It provides a clearly defined tree of axioms that maps the player’s visually manifested affective cues and emotional stimuli from the serious game to conflict handling styles and proposes interventions. The importance of this ontology lies in the fact that it promotes natural interaction (non-invasive methods and at the same time makes the game as player-specific as it can be for its educational goal. It is an ontology that can be adapted to different educational theories and serve various educational purposes.
OFarrell, Zachary L.
Aegis Video Player is the name of the video over IP system for the Telemetry and Communications group of the Launch Services Program. Aegis' purpose is to display video streamed over a network connection to be viewed during launches. To accomplish this task, a VLC ActiveX plug-in was used in C# to provide the basic capabilities of video streaming. The program was then customized to be used during launches. The VLC plug-in can be configured programmatically to display a single stream, but for this project multiple streams needed to be accessed. To accomplish this, an easy to use, informative menu system was added to the program to enable users to quickly switch between videos. Other features were added to make the player more useful, such as watching multiple videos and watching a video in full screen.
Evaluation and treatment of a football player who has sustained life-threatening injuries is a rare but significant challenge for the sports medicine team. Early recognition and intervention in these injuries is crucial. Helmets and shoulder pads complicate management of these patients. In this article, I present a rapid and simple assessment method used by paramedics for trauma patients. Treatment focuses on when football equipment should be removed and how the equipment complicates Advanced...
Hasan, Syed Akif; Subhani, Muhammad Imtiaz; Osman, Ms. Amber
The behavior of following the most in vogue and admired styles of dressing has been there since the ancient times. With time, people have moved on with the rapid change in the surroundings. Both the genders acknowledge fashion. Fashion is an extension of regular clothing. This paper investigates the role of economical players which includes per capita income and inflations in shaping up the various trends/ fashion trends/ trends in clothing and their consumptions for Pakistan, India, United S...
Topič, Mojca Doupona; Šibila, Marko
Abstract The main purpose of this research was to study the characteristics of migration in European women’s handball based on the Slovenian example and to find the differences between the foreigners coming to Slovenia and the Slovenians transferring to foreign clubs. The research was based on 16 open face-to-face semi-structured interviews (8 Slovenians (age 29.5 ± 6.2 years) and 8 foreigners (age 35.5 ± 8.7 years)). We found out that the most powerful factor in foreigners was the financial one, while within Slovenian players it was their personal desire for progression within their sport, the club’s reputation and poor conditions in their previous club. The results confirm that when making a decision on transfer, all players had the support of family and friends, while the clubs of foreign players were not as supportive. Most interviewees considered their careers successful and did not regret going abroad. The research indicates that the largest differences discovered between Slovenians and foreigners were that foreign female players chose to stay in the new country (Slovenia), while domestic players returned home after few years playing abroad. In conclusion, the results show that in top-level handball there are important differences between migration models which are based on nationality and also that the migration models change throughout time, which is largely connected with the socioeconomic events in the country of origin or transfer. PMID:28149349
Full Text Available The main purpose of this research was to study the characteristics of migration in European women’s handball based on the Slovenian example and to find the differences between the foreigners coming to Slovenia and the Slovenians transferring to foreign clubs. The research was based on 16 open face-to-face semi-structured interviews (8 Slovenians (age 29.5 ± 6.2 years and 8 foreigners (age 35.5 ± 8.7 years. We found out that the most powerful factor in foreigners was the financial one, while within Slovenian players it was their personal desire for progression within their sport, the club’s reputation and poor conditions in their previous club. The results confirm that when making a decision on transfer, all players had the support of family and friends, while the clubs of foreign players were not as supportive. Most interviewees considered their careers successful and did not regret going abroad. The research indicates that the largest differences discovered between Slovenians and foreigners were that foreign female players chose to stay in the new country (Slovenia, while domestic players returned home after few years playing abroad. In conclusion, the results show that in top-level handball there are important differences between migration models which are based on nationality and also that the migration models change throughout time, which is largely connected with the socioeconomic events in the country of origin or transfer.
Bohm, Philipp; Ditzel, Roman; Ditzel, Heribert; Urhausen, Axel; Meyer, Tim
The purpose of the study was to evaluate ECG abnormalities in a large sample of elite football players. Data from 566 elite male football players (57 of them of African origin) above 16 years of age were screened retrospectively (age: 20.9 ± 5.3 years; BMI: 22.9 ± 1.7 kg · m(-2), training history: 13.8 ± 4.7 years). The resting ECGs were analysed and classified according to the most current ECG categorisation of the European Society of Cardiology (ESC) (2010) and a classification of Pelliccia et al. (2000) in order to assess the impact of the new ESC-approach. According to the classification of Pelliccia, 52.5% showed mildly abnormal ECG patterns and 12% were classified as distinctly abnormal ECG patterns. According to the classification of the ESC, 33.7% showed 'uncommon ECG patterns'. Short-QT interval was the most frequent ECG pattern in this group (41.9%), followed by a shortened PR-interval (19.9%). When assessed with a QTc cut-off-point of 340 ms (instead of 360 ms), only 22.2% would have had 'uncommon ECG patterns'. Resting ECG changes amongst elite football players are common. Adjustment of the ESC criteria by adapting proposed time limits for the ECG (e.g. QTc, PR) should further reduce the rate of false-positive results.
Mlynarek, Ryan A; Coleman, Struan H
To discuss the clinical significance of the most common hip and groin injuries in baseball players, as well as an algorithmic approach to diagnosis and treatment of these injuries. (a) Limitations in throwing velocity, pitch control, and bat swing speed may be secondary to decreased mobility and strength within the proximal kinetic chain, which must harness power from the lower extremities and core. (b) Approximately 5.5% of all baseball injuries per year involve the hip/groin and may lead to a significant amount of time spent on the disabled list. Injuries involving the hip and groin are relatively common in baseball players. Our knowledge of the mechanics of overhead throwing continues to evolve, as does our understanding of the contribution of power from the lower extremities and core. It is paramount that the team physician be able to accurately diagnose and treat injuries involving the hip/groin, as they may lead to significant disability and inability to return to elite levels of play. This review focuses on hip- and groin-related injuries in the baseball player, including femoroacetabular impingement, core muscle injury, and osteitis pubis.
Full Text Available This paper focuses on the contribution of Australian Football League (AFL players to their team's on-field network by simulating player interactions within a chosen team list and estimating the net effect on final score margin. A Visual Basic computer program was written, firstly, to isolate the effective interactions between players from a particular team in all 2011 season matches and, secondly, to generate a symmetric interaction matrix for each match. Negative binomial distributions were fitted to each player pairing in the Geelong Football Club for the 2011 season, enabling an interactive match simulation model given the 22 chosen players. Dynamic player ratings were calculated from the simulated network using eigenvector centrality, a method that recognises and rewards interactions with more prominent players in the team network. The centrality ratings were recorded after every network simulation and then applied in final score margin predictions so that each player's match contribution-and, hence, an optimal team-could be estimated. The paper ultimately demonstrates that the presence of highly rated players, such as Geelong's Jimmy Bartel, provides the most utility within a simulated team network. It is anticipated that these findings will facilitate optimal AFL team selection and player substitutions, which are key areas of interest to coaches. Network simulations are also attractive for use within betting markets, specifically to provide information on the likelihood of a chosen AFL team list "covering the line".
Full Text Available Aim: The purpose of this study is to research the differences of genotype polymorphism between the elite male and elite female basketball player, volleyball player and control group. Material and Methods: 58 basketball players (ages 24.25±4.99 years, height 188.22±12.31 cm and weight 80.62±16.34 kg, 64 volleyball players (ages 22.82±5.40 years, height 188.67±9.69 cm and weight 77.82±12.14 kg and 122 sedentary subjects (control group were participated randomly in the study. 5cc blood was taken control and control groups for measuring the ACE gene polymorphism. Chi-square and analysis of variance (ANOVA, Levene’s Tests, and frequencies of allele were used for statistical evaluation at significance level p0.05, basketball, volleyball and control group (p>0.05, male basketball, volleyball and control group (p>0.05, female basketball, volleyball and control group (p>0.05 and male and female athletes (p>0.05 respectively. There were no significance differences in male athletes between the genotype distribution and physical performance tests, such as 20m shuttle-run (F=1.31, vertical jump (F=0.22, and 20m sprint test (F=0.44. There were also no significance differences in female athletes between the genotype distribution and physical performance tests, such as 20m shuttle-run (F=2.03, vertical jump (F=0.10, and 20m sprint test (F=1.17. Conclusion: ACE polymorphism genotype distribution in terms of elite female and male volleyball players with elite female and male basketball players are the same.
Deborah L. Feairheller
Full Text Available Studies report that football players have high blood pressure (BP and increased cardiovascular risk. There are over 70,000 NCAA football players and 450 Division III schools sponsor football programs, yet limited research exists on vascular health of athletes. This study aimed to compare vascular and cardiovascular health measures between football players and nonathlete controls. Twenty-three athletes and 19 nonathletes participated. Vascular health measures included flow-mediated dilation (FMD and carotid artery intima-media thickness (IMT. Cardiovascular measures included clinic and 24 hr BP levels, body composition, VO2 max, and fasting glucose/cholesterol levels. Compared to controls, football players had a worse vascular and cardiovascular profile. Football players had thicker carotid artery IMT (0.49 ± 0.06 mm versus 0.46 ± 0.07 mm and larger brachial artery diameter during FMD (4.3±0.5 mm versus 3.7±0.6 mm, but no difference in percent FMD. Systolic BP was significantly higher in football players at all measurements: resting (128.2±6.4 mmHg versus 122.4±6.8 mmHg, submaximal exercise (150.4±18.8 mmHg versus 137.3±9.5 mmHg, maximal exercise (211.3±25.9 mmHg versus 191.4±19.2 mmHg, and 24-hour BP (124.9±6.3 mmHg versus 109.8±3.7 mmHg. Football players also had higher fasting glucose (91.6±6.5 mg/dL versus 86.6±5.8 mg/dL, lower HDL (36.5±11.2 mg/dL versus 47.1±14.8 mg/dL, and higher body fat percentage (29.2±7.9% versus 23.2±7.0%. Division III collegiate football players remain an understudied population and may be at increased cardiovascular risk.
Bauckhage, Christian; Kersting, Kristian; Sifa, Rafet
introduce methods from random process theory into game data mining in order to draw inferences about player engagement. Given large samples (over 250,000 players) of behavioral telemetry data from five different action-adventure and shooter games, we extract information as to how long individual players......Analyzing telemetry data of player behavior in computer games is a topic of increasing interest for industry and research, alike. When applied to game telemetry data, pattern recognition and statistical analysis provide valuable business intelligence tools for game development. An important problem...... in this area is to characterize how player engagement in a game evolves over time. Reliable models are of pivotal interest since they allow for assessing the long-term success of game products and can provide estimates of how long players may be expected to keep actively playing a game. In this paper, we...
Fahlström, M; Söderman, K
The aim of this study was to describe the prevalence and consequences of painful conditions in the shoulder region in recreational badminton players. A questionnaire study was performed on 99 players, of whom 57 were also assessed with Constant score. Previous or present pain in the dominant shoulder was reported by 52% of the players. Sixteen percent of the players had on-going shoulder pain associated with badminton play. A majority of these players reported that their training habits were affected by the pain. Total Constant score was lower in the painful shoulders. Furthermore, range of active pain-free shoulder abduction was decreased. However, isometric shoulder strength test showed no differences when compared with pain-free shoulders. Even though the pain caused functional problems, the players were still playing with on-going symptoms. The diagnoses were mostly unknown, although history and clinical tests indicate problems resembling subacromial impingement.
Full Text Available The aim of this descriptive study is to determine the incidence of injuries among recreational badminton players. We evaluated 86 recreational badminton players in the city of Malacca; 35 were excluded for fitting the exclusion criteria. The average recreational badminton player was 36.13 years old and had been playing badminton for the past 17.84 years at a frequency of 2.11 times per week. 39.21% of the recreational badminton players complained of recent injuries in relation to playing badminton. Our data showed that the most common injury sustained by recreational badminton players was pain and stiffness at the shoulder joint. None of the injuries sustained by the players in our data were serious enough to warrant any form of surgical intervention. We conclude that badminton is a sport of relatively low risk and that the majority of related injuries were chronic overuse injuries.
Teng, Ching-I; Lo, Shao-Kang; Wang, Pe-Cheng
This study investigated how different adolescent players acquire game information and the criteria they use in choosing online games and found that (1) current players generally use comprehensive information sources more than potential players do; (2) current players rely on free trials and smooth display of motion graphics as choice criteria more than potential players do; (3) potential players rely on the look of advertisements more than current players do; (4) both current and potential players most likely use word-of-mouth and gaming programs on TV as information sources; and (5) endorser attractiveness is ranked the least important among six choice criteria by both current and potential players.
Ito E; Iwamoto J; Azuma K; Matsumoto H
Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball player...
Objectives: Athlete’s nutritional habits and knowledge can directly affect their performance. The purpose of this study is to investigate the nutritional habits and knowledge of the Division I collegiate football player. Methods: The participants of this study are male Division I college football players at Utah State University. The athletes included 45 players ranging from 18-26 and include freshman through seniors. Results: Over eighty six percent of the athletes were unaware that a ...
Gyarmati, Laszlo; Hefeeda, Mohamed
It is challenging to get access to datasets related to the physical performance of soccer players. The teams consider such information highly confidential, especially if it covers in-game performance.Hence, most of the analysis and evaluation of the players' performance do not contain much information on the physical aspect of the game, creating a blindspot in performance analysis. We propose a novel method to solve this issue by deriving movement characteristics of soccer players. We use eve...
Tambe, Amol; Badge, Ravi; Funk, Lennard
Background: Rugby is an increasingly popular collision sport. A wide spectrum of injuries can be sustained during training and match play. Rotator cuff injury is uncommon in contact sports and there is little published literature on the treatment of rotator cuff tears in rugby players. Aims: We therefore reviewed the results and functional outcomes of arthroscopic rotator cuff repair in elite rugby players. Materials and Methods: Eleven professional rugby players underwent arthroscopic ...
Barbero Álvarez, José Carlos; Gómez López, Maite; Barbero Álvarez, Verónica; Granda Vera, Juan; Castagna, Carlo
The physical and physiological demands of high-level male soccer have been studied extensively, while few studies have investigated the demands placed on females during match-play, however, there is no information available about the heart rate and activity profile of young female soccer players during match play. Therefore, the aim of this study was to examine cardiovascular (heart-rates HR) and physical demands of young female soccer players during a match. Players were observed during a fr...
The results are guidelines for game developers to improve their game design. Through using the guidelines of the paper, developers know how to implement appealing online game elements which appeal to the player and draw them in. The result of the thesis are socializing, achievements and immersion are motivated the player to play online games, as well as the way online games stimulate the player's brain.
Maughan, R J
OBJECTIVE: To examine the dietary habits of professional soccer players at two Scottish Premier League clubs during the competitive season. METHODS: A study of the dietary intake of 51 professional soccer players with two different clubs was carried out by the seven day weighed intake method. RESULTS: Physical characteristics of the two groups of players were similar, with only small differences in age and body mass but no difference in height and body fat. Mean (SD) daily energy intake for c...
Grappiolo, C.; Cheong, Yun-Gyung; Togelius, J.
to resolve this type of conflict, the underlying system generates level content automatically which adapts to player experience and behaviour. Preliminary results demonstrate the efficiency of the procedural content generation mechanism in guiding the training of players towards targeted learning objectives.......We present a technology demonstrator for an adaptive serious game for teaching conflict resolution and discuss the research questions associated with the project. The prototype is a single-player 3D mini-game which simulates a resource management conflict scenario. In order to teach the player how...
Kaye, Linda K; Gresty, Claire E; Stubbs-Ennis, Natasha
Gender stereotypes are still reported to exist in digital gaming contexts, despite the fact that participation of females is relatively equal to that of males. The current research explored a number of factors and their impact upon stereotypical perceptions and attitudes toward female players. This included avatar gender, gender identity by gaming context, as well as more general gender-role beliefs. We undertook two studies, each utilizing an online questionnaire targeted toward online players. Study 1 recruited online gamers (N = 489) and compared competence perceptions of players, which varied by player gender (male, female) and avatar gender (male, female), whereby four conditions were established. Overall, player competence was perceived to be highest when male avatars were used, specifically when female players were depicted in this way. Study 2 explored the relationships between male social identity and gender-role beliefs, with sexist attitudes in gaming, and whether this varied by gaming context (massively multiplayer online [MMO] vs. first-person shooter [FPS]). Male online gamers (N = 193) were recruited, of which 112 were MMO players, and 81 were FPS players. It was found that identifying as male social identity was not related to sexist attitudes in either gaming context. However, more general gender-role beliefs were related to sexist attitudes. The findings indicate that although certain stereotypes exist (e.g., competence perceptions), these are not necessarily harvested by players' identities within communities, but may derive through more operational functions such as avatar gender.
Martin, W.E.; Patrick, R.H.; Tolwinski, B.
Modeling transboundary pollutants in a dynamic game framework provides a foundation for analyzing the impact of various policy options. The focus of this analysis is on the results of a tax/subsidy scheme used to address the transboundary problem of global climate change. A nonzero-sum dynamic game with asymmetric players is used to evaluate the policy impact of the tax/subsidy scheme on the respective player's value functions and strategies as determined by a Nash equilibrium feedback solution. The asymmetry of the players is reflected in their respective attitudes toward global climate change with one player benefiting from the change and the other losing. 17 refs., 5 tabs
Ostojic, Sergej M; Mazic, Sanja; Dikic, Nenad
The purpose of this study was to describe structural and functional characteristics of elite Serbian basketball players and to evaluate whether players in different positional roles have different physical and physiological profiles. Five men's basketball teams participated in the study and competed in the professional First National League. Physiological measurements were taken of 60 players during the final week of their preparatory training for competition. According to positional roles, players were categorized as guards (n = 20), forwards (n = 20), and centers (n = 20). Guards were older (p Vertical jump power was significantly higher in centers (p basketball.
Full Text Available This study measured and compared the frequency, magnitude, and distribution of head impacts sustained by junior and adult Australian football players, respectively, and between player positions over a season of games. Twelve junior and twelve adult players were tracked using a skin-mounted impact sensor. Head impact exposure, including frequency, magnitude, and location of impacts, was quantified using previously established methods. Over the collection period, there were no significant differences in the impact frequency between junior and adult players. However, there was a significant increase in the frequency of head impacts for midfielders in both grades once we accounted for player position. A comparable amount of head impacts in both junior and adult players has implications for Australian football regarding player safety and medical coverage as younger players sustained similar impact levels as adult players. The other implication of a higher impact profile within midfielders is that, by targeting education and prevention strategies, a decrease in the incidence of sports-related concussion may result.
Wagner-Egger, Pascal; Gygax, Pascal; Ribordy, Farfalla
This experiment investigated challenge evaluations in soccer and their relation to prejudice: more precisely, whether skin colour may influence judgments of soccer tackles. Three groups of participants (soccer players, referees,and soccer fans) were asked to evaluate challenges, featuring Black and White players as aggressors and victims in a mixed-design study. Results showed that participants made some differentiations between Black and White players in a challenge evaluation task. Participants were more likely to consider within-group challenges as fouls and were faster to consider challenges made by Black players as fouls. On the other hand, fouls made by White players were seen as more severe. There were no major differences between the participating groups, suggesting that the observed effects were independent of how good players were or whether the participants were referees or not.
Mankins, Michael; Bird, Alan; Root, James
Top talent is an invaluable asset: In highly specialized or creative work, for instance, "A" players are likely to be six times as productive as "B" players. So when your company has a crucial strategic project, why not multiply all that firepower and have a team of your best performers tackle it? Yet many companies hesitate to do this, believing that all-star teams don't work: Big egos will get in the way. The stars won't be able to work with one another. They'll drive the team Leader crazy. Mankins, Bird, and Root of Bain & Company believe it's time to set aside that thinking. They have seen all-star teams do extraordinary work. But there is a right way and a wrong way to organize them. Before you can even begin to assemble such a team, you need to have the right talent management practices, so you hire and develop the best people and know what they're capable of. You have to give the team appropriate incentives and leaders and support staffers who are stars in their own right. And projects that are ill-defined or small scale are not for all-star teams. Use them only for critical missions, and make sure their objectives are clear. Even with the right setup, things can still go wrong. The wise executive will take steps to manage egos, prune non-team-players, and prevent average coworkers from feeling completely undervalued. She will also invest a lot of time in choosing the right team Leader and will ask members for lots of feedback to monitor how that leader is doing.
Otaka, Machiko; Chen, Shu-Man; Zhu, Yong; Tsai, Yung-Shen; Tseng, Ching-Yu; Fogt, Donovan L; Lim, Boon-Hooi; Huang, Chih-Yang; Kuo, Chia-Hua
Scientific data on the performance of collegiate female tennis players during the menstrual phases are scarce. Double-blind, counter-balanced, crossover trials were conducted to examine whether tennis performance was affected during menstruation, with and without dehydroepiandrosterone sulfate (DHEA-S) supplementation. Ten Division 1 collegiate tennis players (aged 18-22 years) were evenly assigned into placebo-supplemented and DHEA-supplemented (25 mg/day) trials. Treatments were exchanged among the participants after a 28-day washout. Tennis serve performance was assessed on the first day of menstrual bleeding (day 0/28) and on days 7, 14 and 21. Mood state was unaltered during the menstrual cycles in both trials. The lowest tennis serve performance score (speed times accuracy) occurred on day 14 (P=0.06 vs day 0; P=0.01 vs day 21) in both placebo and DHEA trials. Decreased performance on day 14 was explained by decreased accuracy (P=0.03 vs day 0/28; P=0.01 vs day 21), but not velocity itself. Isometric hip strength, but not quadriceps strength, was moderately lower on day 14 (P=0.08). Increasing plasma DHEA-S (by ~65%) during the DHEA-supplemented trial had no effects on mood state, sleep quality or tennis serve performance. We have shown that menses does not affect serve performance of collegiate tennis players. However, the observed decrement in the accuracy of serve speed near ovulation warrants further investigation.
Soccer is one of the most widely played and complex sports in the world, where success depends on technical, tactical and physical skills of the players. Studies to improve performance in soccer have often focused on technique and tactics. However, nutrition is one of the most important factors influencing athletic performance of the players. The duration of matches is long and the training is intense. This leads to increased requirements for energy and nutrients, as well as increased reactive oxygen radicals and hence increased muscle damage. Vitamins are micronutrients that a living organism requires in trace quantities for health. As these assume crucial functions in the body, the performance of the player is negatively affected particularly during long-term deficiency. Beta-carotene, C and E vitamins are antioxidants that protect against oxygen radicals. In case of their deficiency, oxidative stress and muscle fatigue increases. Vitamin D is involved in maintaining mineral balance, and it increases absorption of dietary calcium and phosphorus. In case of vitamin D deficiency, injuries resulting from the musculoskeletal system might increase. B Vitamins (B1, B2, niacin, B6, B12, biotin, folic acid and pantothenic acid) perform duties such as energy production, absorption and transport of iron and blood cell production. Athletes who follow an energy-restricted and imbalanced diet might develop vitamin deficiency. In such a case, supplements can be used as recommended by the doctor/dietician. It is further reported that supplement use by athletes who have an adequate and balanced nutrition does not increase performance.
Full Text Available In imperfectly discriminating contests with symmetric valuations, equilibrium payoffs are positive shares of the value of the prize. In contrast to a bargaining situation, players’ shares sum to less than one because a residual share of the value is lost due to rent dissipation. In this paper, we consider contests with two players and investigate the relationship between these equilibrium shares and the parameters of a class of asymmetric Tullock contest success functions. Our main finding is that any players’ shares that sum up to less than one can arise as the unique outcome of a pure-strategy Nash equilibrium for appropriate parameters.
Sidorenko, A V; Mikhaĭlova, O N
This review article is devoted to the issues of international cooperation on ageing. It aims at describing the basic areas of cooperation and introducing its major players. Within the limited length of a journal article it is hardly possible to offer an exhaustive presentation of all available information; thus the article strives to provide a general orientation within the selected themes. The authors are hopeful that the presented materials will be of interest to the policy oriented researchers, policy makers and professionals working in the field of ageing and related areas such as social security, health and social services etc., as well as to the activists of non-governmental organizations.
Bray, A E; Lewis, W A
Intermittent claudication in a professional rugby player is described. The typical features of a delayed and difficult diagnosis of an external iliac artery stenosis were found. The noninvasive diagnostic protocol used to investigate this young patient with a minimal arterial lesion enabled accurate localization and angioplasty to be performed at the same time as diagnostic angiography. The patient was symptom free with normal arterial pressures on follow-up. It is suggested that appropriate noninvasive investigations should be performed before angiography in young people with minimal lesions.
Full Text Available The main goal of this research is to determine whether and what differences exist between the three groups of subjects (high-quality football, volleyball and basketball cadets and youth age, in the motoric and functional abilities, as well as to identify dif- ferences between subgroups within each sport. The sample consists of 61 volleyball, 31 basketball player and football player 31 (total n = 123 male, cadet and youth age are members of local clubs. Subjects were born between 01.01.1991 and 12.12.1994. The sample of variables are the values of 17 tests for the evaluation of functional and mobile status. The Motor-functional status on the basis of the results of secondary value of foot- ball, basketball and volleyball make a clear conclusion that the football players showed the best results in almost all the tests and that they had the smallest disbalance in the power of certain groups of muscles.The football players hve the highest homogeneity.
Wong Zhen Feng
Full Text Available Background: Shoulder pain is a common reason for patients to seek medical help in any healthcare center. Shoulder pain is influenced by a few factors such as gender, posture during daily activities, aging and psychological factors. Based on the study of Epidemiology of Injuries and Prevention Strategies in Competitive Swimmers, shoulder pain due to shoulder injuries can be reduced by strengthening the shoulder muscle. Badminton has become one of the most popular sports in Asia, especially in Indonesia. This study was conducted to determine if badmintonis able to strengthen the shoulder muscle group. Methods: A cross-sectional analytic experimental study was conducted on September 2015 at Lodaya Badminton Training Center and Bale Padjadjaran of Universitas Padjadjaran. Subjects were 30 healthy male routinely trained badminton players and 30 non-badminton players who voluntarily follow the rstudy procedures. Strength measurement procedures were provided to the subjects after getting informed consent. Data analysis was performed using T-test. Results: The shoulder strength in routinely trained badminton players was significantly different from non-badminton players (P<0.05. Conclusions: Shoulder strength can be improved through routine training of badminton to reduce risk of shoulder injury. DOI: 10.15850/amj.v4n2.1083
Full Text Available A comparative analysis of the psychophysiological features of skilled basketball players with normal hearing and impaired hearing aid. The study involved two women's basketball team to 12 people each. The study used a complex computer psychodiagnosis. The complex includes 20 psychophysiological and 18 personal psychological tests. The indicators of the time simple and complex reaction and average tapping test healthy skilled basketball players and basketball players are hearing impaired. There was a significant higher rates of visual-motor speed and reaction-tapping test in basketball players with hearing compared to healthy athletes. This is explained by compensatory mechanisms that occur in connection with the violation of the audition.
Full Text Available A comparative analysis of the psychophysiological features of skilled basketball players with normal hearing and impaired hearing aid. The study involved two women's basketball team to 12 people each. The study used a complex computer psychodiagnosis. The complex includes 20 psychophysiological and 18 personal psychological tests. The indicators of the time simple and complex reaction and average tapping test healthy skilled basketball players and basketball players are hearing impaired. There was a significant higher rates of visual-motor speed and reaction-tapping test in basketball players with hearing compared to healthy athletes. This is explained by compensatory mechanisms that occur in connection with the violation of the audition.
Bartolom\\u00E9 J. Almagro
Full Text Available The motivation of an athlete is determinant for the athletic engagement of the adolescent. The present study attempts to analyze the motivation of adolescent basketball and football players from the perspectives of Achievement Goal Theory (Nicholls, 1989 and Self-Determination Theory (Deci & Ryan, 1985. The study's sample was composed of 248 athletes from 12 to 17 years of age. Half were from basketball and half were from football. The instruments that were utilized were: the Spanish version of the Sport Motivation Scale (SMS (Núñez, Martín-Albo, Navarro, & González, 2006, the Spanish version of the Perceived Motivational Climate in Sport Questionnaire-2 (PMSCQ-2 (Balaguer, Mayo, Atienza, & Duda, 1997, and the adapted Spanish translation (Moreno, Moreno, & Cervelló, 2007 of the Intention to be Physically Active Scale (IPAS by Hein, Müür, and Koka (2004. The comparison of the means of the variables between football and basketball players was done utilizing the student t-test for independent samples. Significant differences were found for variables such as: intrinsic motivation (IM toward accomplishment, external regulation, amotivation, task, ego, and Self-Determination Index (SDI. Basketball players obtained higher values in the SDI, in task, and in IM toward accomplishment than football players. The search for premature performance in football and coaches' educations can help to explain these differences. The importance of these differences reside in the relationship between these motivational variables and the adherence to athletic practice. In conclusion, basketball demonstrated better values in motivational variables, which demonstrates that training sessions are more oriented toward task than ego, that players have more intrinsic and self-determined motivation, and therefore, the adherence of the young athletes will be greater in this sport.
Ito, Eri; Iwamoto, Jun; Azuma, Koichiro; Matsumoto, Hideo
The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females) were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%), and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%). The proportion of anterior cruciate ligament injury in the 10-19-year-old age group was higher among female players than among male players (45.9% vs 22.1%), while the proportions of Osgood-Schlatter disease in the 10-19-year-old age group and jumper's knee (patellar and femoral tendinopathy) in the 20-29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively). However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.
Full Text Available Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%, and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%. The proportion of anterior cruciate ligament injury in the 10–19-year-old age group was higher among female players than among male players (45.9% vs 22.1%, while the proportions of Osgood–Schlatter disease in the 10–19-year-old age group and jumper's knee (patellar and femoral tendinopathy in the 20–29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively. However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.Keywords: sports injury, sex, anterior cruciate ligament injury, Osgood–Schlatter disease, basketball
Hadzic, Vedran; Sattler, Tine; Veselko, Matjaž; Markovic, Goran; Dervisevic, Edvin
Volleyball players are reported to have shoulder strength imbalances. Previous authors have primarily investigated small samples of male players at a single skill level, without considering playing position, and with inconsistent findings. To evaluate shoulder strength asymmetry and a history of shoulder injury in a large sample of professional volleyball players of both sexes across different playing positions and skill levels. Descriptive laboratory study. A sample of 183 volleyball players (99 men, 84 women). We assessed shoulder internal-rotator and external-rotator concentric strength at 60°/s using an isokinetic dynamometer and dominant-nondominant differences in shoulder strength and strength ratios using repeated-measures analyses of variance. Peak torque was normalized for body mass and external-rotation/internal-rotation concentric strength. Internal-rotation strength was asymmetric in favor of the dominant side in both sexes, regardless of previous shoulder injury status. Male volleyball players had a lower shoulder strength ratio on the dominant side, regardless of previous shoulder injury status. However, this finding was valid only when hand dominance was taken into account. Female volleyball players playing at a higher level (ie, first versus second division) were 3.43 times more likely to have an abnormal strength ratio. Playing position was not associated with an abnormal shoulder strength ratio or strength asymmetry. In male volleyball players, the external-rotation/internal-rotation strength ratio of the dominant shoulder was lower, regardless of playing position, skill level, or a previous shoulder injury. In female players, the ratio was less only in those at a higher skill level. Although speculative, these findings generally suggest that female volleyball players could have a lower risk of developing shoulder-related problems than male volleyball players. Isokinetic shoulder testing may reveal important information about the possible risk
James M Chappell
Full Text Available The N-player quantum games are analyzed that use an Einstein-Podolsky-Rosen (EPR experiment, as the underlying physical setup. In this setup, a player's strategies are not unitary transformations as in alternate quantum game-theoretic frameworks, but a classical choice between two directions along which spin or polarization measurements are made. The players' strategies thus remain identical to their strategies in the mixed-strategy version of the classical game. In the EPR setting the quantum game reduces itself to the corresponding classical game when the shared quantum state reaches zero entanglement. We find the relations for the probability distribution for N-qubit GHZ and W-type states, subject to general measurement directions, from which the expressions for the players' payoffs and mixed Nash equilibrium are determined. Players' N x N payoff matrices are then defined using linear functions so that common two-player games can be easily extended to the N-player case and permit analytic expressions for the Nash equilibrium. As a specific example, we solve the Prisoners' Dilemma game for general N ≥ 2. We find a new property for the game that for an even number of players the payoffs at the Nash equilibrium are equal, whereas for an odd number of players the cooperating players receive higher payoffs. By dispensing with the standard unitary transformations on state vectors in Hilbert space and using instead rotors and multivectors, based on Clifford's geometric algebra (GA, it is shown how the N-player case becomes tractable. The new mathematical approach presented here has wide implications in the areas of quantum information and quantum complexity, as it opens up a powerful way to tractably analyze N-partite qubit interactions.
Noelia Belando Pedreño
Full Text Available The aim of this study was to contribute to the postulates of the self-determination theory, the hierarchical model of intrinsic and extrinsic motivation by Vallerand, and social goals. A structural regression model was estimated to analyze the relations between social goals (responsibility and relationships, praise for autonomous behavior, satisfaction of the basic psychological needs and intrinsic motivation in commitment to sport. A sample of 264 young Spanish soccer players aged between 14 and 16 (M =14.74, SD =.77 participated in the study. Structural Equation Modeling results showed that the social responsibility goal, the social relationship goal and praise for autonomous behavior predicted perceived competence. Furthermore, the relationship goal also predicted the need for relatedness. Satisfaction of the basic psychological needs for competence and relatedness predicted intrinsic motivation. Intrinsic motivation positively predicted future commitment to sport. These results highlighted the importance of social goals, praise for autonomous behavior and psychological mediators in encouraging greater commitment in young soccer players. Future research should focus on the coach’s role in generating greater commitment to sport through the development of intervention methodologies based on social goals.
Marcos Roberto Queiroga
Full Text Available http://dx.doi.org/10.5007/1980-0037.2008v10n1p56 The present study aimed to verify whether body somatotype was indicative of competitive success in female utsal (indoor soccer players. One hundred and twelve players (22.1 ± 5.4 years; 58.4 ± 6.9 kg; 161.8 ± 6.2 cm, from ten teams and seven different states, had participated in a national competition. The anthropometric date was analyzed using one-way ANOVA for repeated measures. The somatotype dispersion distance was applied to compare somatotypes between the champion team (reference and the other teams (from 2nd to 10th position. Anthropometric characteristics did not differ signifi cantly among teams. The results showed that the endomorphic component was predominant in relation to the mesomorphic and ectomorphic component, irrespective of a team’s ranking at the end of the competition. Therefore, the body somatotypes of female futsal teams cannot be considered as indicative of their competitive success.
Full Text Available Literature has revealed the importance of quantifying resting scapular posture in overhead athletes as well as quantifying scapular kinematics during dynamic movement. Prior to this project much of the attention in throwing research had been focused on the position of the humerus without description of the positioning of the scapula. Therefore, it was the purpose of this study to present scapular kinematics during pitching in youth baseball players. Twenty-five youth baseball players (age 11.3 + 1.0 years; body height 152.4 + 9.0 cm; body mass 47.5 + 11.3 kg, with no history of injury, participated in the study. Scapular kinematics at the events of maximum humeral external rotation (MER and maximum humeral internal rotation (MIR during the pitching motion were assessed three-dimensionally while pitching fastballs for strikes. Results revealed that at the event of MER, the scapula was in a position of retraction, upward rotation and a posterior tilt. While at the event of MIR, the scapula was protracted, upward rotated and tilted anteriorly.
Goh, S L; Mokhtar, A H; Mohamad Ali, M R
The aim of the study was to examine sports injury pattern and establish cost of injuries in relation to training of 58 competitive badminton players in a Malaysian National Sports School. This one-year prospective observational study recruited all the 13-16 year old students after obtaining informed consent from their appointed guardian. All participants were requested to report any injuries, which were pain or disabilities that occur within the study period (September 1, 2008 to August 31, 2009) either during training or competition. Injured students were to seek treatment from the researcher(s) who made weekly visits and they were then followed up accordingly until they return to full training. Details and progress of the injuries were documented during each visit. Sixty-three injuries were recorded. Soft tissue sprains/strains were the commonest injury (64%). About one third of the injuries occurred in the lower limb especially the knees and was followed by back injuries; 38% of the injuries did not require training modification, half of these injuries resumed training within one week. Upon full training, half of them were still symptomatic. Injury risk was 57%; injury rate was 0.9 injuries/ player/1000 training hours. Badminton injuries mostly involved the lower limb and almost all overuse injuries occurred in the lower limb. However, badminton injuries as a whole were predominantly sprains and strains, and not overuse in nature as widely believed.
McGuine, Timothy A.; Hetzel, Scott; McCrea, Michael; Brooks, M. Alison
Background The incidence of sport-related concussion (SRC) in high school football is well documented. However, limited prospective data are available regarding how player characteristics and protective equipment affect the incidence of SRC. Purpose To determine whether the type of protective equipment (helmet and mouth guard) and player characteristics affect the incidence of SRC in high school football players. Design Cohort study; Level of evidence, 2. Methods Certified athletic trainers (ATs) at each high school recorded the type of helmet worn (brand, model, purchase year, and recondition status) by each player as well as information regarding players’ demographics, type of mouth guard used, and history of SRC. The ATs also recorded the incidence and days lost from participation for each SRC. Incidence of SRC was compared for various helmets, type of mouth guard, history of SRC, and player demographics. Results A total of 2081 players (grades 9–12) enrolled during the 2012 and/or 2013 football seasons (2287 player-seasons) and participated in 134,437 football (practice or competition) exposures. Of these players, 206 (9%) sustained a total of 211 SRCs (1.56/1000 exposures). There was no difference in the incidence of SRC (number of helmets, % SRC [95% CI]) for players wearing Riddell (1171, 9.1% [7.6%–11.0%]), Schutt (680, 8.7% [6.7%–11.1%]), or Xenith (436, 9.2% [6.7%–12.4%]) helmets. Helmet age and recondition status did not affect the incidence of SRC. The rate of SRC (hazard ratio [HR]) was higher in players who wore a custom mouth guard (HR = 1.69 [95% CI, 1.20–2.37], P football players. Players who had sustained an SRC within the previous 12 months were more likely to sustain an SRC than were players without a history of SRC. Sports medicine providers who work with high school football players need to realize that factors other than the type of protective equipment worn affect the risk of SRC in high school players. PMID:25060072
Following the formation of a single body to govern rugby in South. Africa in 1992, the ... Players from across the country were identified and invited to various ... different levels of rugby cannot be evaluated because the players representing ..... programmes for youth and young adults is the disparity in body size and fitness of ...
te Wierike, Simon; Lemmink, Koen; de Jong, M.C.; Tromp, E.J.; Vuijk, P.J.; Malina, R.M.; Elferink-Gemser, Marije; Visscher, Chris
Factors affecting repeated sprint ability (RSA) were evaluated in a mixed-longitudinal sample of 48 elite basketball players 14 to 19 years of age (16.1±1.7 years). Players were observed on six occasions during the 2008-2009 and 2009-2010 seasons. Three basketball-specific field tests were
Rugby union is a contact sport in which players require high levels of physical fitness, which is a composite of aerobic and anaerobic endurance, muscle strength and power, speed, agility and body composition. The aim of this study was to assess the physical fitness characteristics of elite female rugby union players.
The netball players were assessed for flexibility, speed, agility, power and aerobic endurance. Anthropometrical measurements were also taken. Descriptive statistics were calculated, after which Student s unpaired t-tests were used to compare results between the Boland and Australian under-21 netball players. Results.
The author investigates the labor market structure and determinants of salaries for professional basketball players. An expanded version of the resource perspective is used. A three-tiered model of labor market segmentation is revealed for professional basketball players, but other variables also are important in salary determination. (Author/CH)
James A. Fleming
Full Text Available In this study, the nutritional and recovery habits of tennis players pre-, during, and post-match-play were investigated. Seventy tennis players completed a bespoke nutrition and recovery habits questionnaire, with questions related to the following areas: match preparation, intra-match nutritional habits, situation dependent variables, and post-match nutrition and recovery. On match day-1, the consumption of balanced meals consisting of carbohydrate (CHO, fat and protein, with some micronutrient considerations were reported by 51% of players. On match-days, CHOs were prioritised prior to match-play with CHO dominant meals consumed by the majority of players. During matches, all players adopted a nutritional strategy, with water (94%, banana(s (86% and sports drinks (50% commonly used. Carbohydrate rich nutritional aids, including sports drinks (80% and energy gels (26% were utilised more readily during long matches (>2 h. The day after match-play, 39% of players reported the consumption of “nothing specific”. Multiple post-match recovery strategies were adopted by 80% of players, with foam rolling (77%, ice baths (40%, protein shake intake (37% and hot baths (26% most used. Findings indicate highly variable eating and recovery habits in tennis players pre-, during and post-match-play, with scope for improved practices.
Hansen, Anne-Marie S.; Andersen, Hans Jørgen; Raudaskoski, Pirkko Liisa
mutual awareness, and in general were more passive when they needed to monitor a screen interface that supported the sound environment. Player collaboration was strongest when players negotiated rhythm, while the negotiation of melody was temporally offset and consisted of long individual explorations....
Conditions are described which guarantee that the control strategies adopted by N players constitute an efficient solution, an equilibrium, or a core solution. The system dynamics are described by an Ito equation, and all players have perfect information. It was found that when the set of instantaneous joint costs and velocity vectors is convex, the conditions are necessary.
Miltner, O; Siebert, C; Tschaepe, R; Maus, U; Kieffer, O
The aim of this study was to analyse the efficiency of muscular activity in the trunk stabilisation of professional volleyball players compared to a group of amateur hobby players. The results were compared amongst the groups as well as with a reference group consisting of asymptomatic individuals. The question to be answered was whether or not professional volleyball players possess a characteristic strength profile in their trunk musculature and if differences exist with regard to the individuals' competitive playing level. In this comparative study 12 professional volleyball players (German Bundesliga) and 18 non-professional volleyball players were analysed with regard to their isometric strength profile in all three planes. The reference group was provided by the Proxomed company, which had previously analysed healthy untrained individuals (n = 1045) of various age groups. A sports-specific profile for the musculature of volleyball players revealed a significant reduction in the flexion and rotation strength as well as a well-developed lateral flexion strength (highly significant when compared to the reference group). With reference to the level played, better strength values in flexion and lateral flexion were found among the professional athletes. Professional volleyball players present with a characteristic trunk musculature strength profile. A detailed analysis of the muscle strength of the spine as part of a sports medicine work-up could prove helpful in preventing injuries and overuse problems in professional and hobby volleyball players.
Fleming, James A; Naughton, Robert J; Harper, Liam D
In this study, the nutritional and recovery habits of tennis players pre-, during, and post-match-play were investigated. Seventy tennis players completed a bespoke nutrition and recovery habits questionnaire, with questions related to the following areas: match preparation, intra-match nutritional habits, situation dependent variables, and post-match nutrition and recovery. On match day-1, the consumption of balanced meals consisting of carbohydrate (CHO), fat and protein, with some micronutrient considerations were reported by 51% of players. On match-days, CHOs were prioritised prior to match-play with CHO dominant meals consumed by the majority of players. During matches, all players adopted a nutritional strategy, with water (94%), banana(s) (86%) and sports drinks (50%) commonly used. Carbohydrate rich nutritional aids, including sports drinks (80%) and energy gels (26%) were utilised more readily during long matches (>2 h). The day after match-play, 39% of players reported the consumption of "nothing specific". Multiple post-match recovery strategies were adopted by 80% of players, with foam rolling (77%), ice baths (40%), protein shake intake (37%) and hot baths (26%) most used. Findings indicate highly variable eating and recovery habits in tennis players pre-, during and post-match-play, with scope for improved practices.
Giagazoglou, Paraskevi; Katis, Athanasios; Kellis, Eleftherios; Natsikas, Christos
The purpose of the current study was to examine the kinematic differences during instep soccer kicks between players who were blind and sighted controls. Eleven male soccer players who were blind and nine male sighted performed instep kicks under static and dynamic conditions. The results indicated significantly higher (p less than 0.05) ball…
The purpose of this study was to establish the fitness profile of the elite junior badminton players in South Africa through the measurement and description of their body composition, aerobic power, muscular characteristics, speed, flexibility and agility. Eight elite male and seven elite female badminton players between the ...
... in prospective studies at the same schools. The players' knowledge of techniques known to prevent rugby injuries was inadequate and too little attention was paid at the start of the rugby season to training and coaching techniques to reduce injury risk. Coaching errors may therefore have predisposed players to injury.
Bontchev, Boyan; Vassileva, Dessislava
Detection of learning curves of player metrics is very important for the serious (or so called applied) games, because it provides an indicator representing how players master the game tasks by acquiring cognitive abilities, knowledge, and necessary skills for solving the game challenges. Real
The aim of this study was to determine the most significant of physical fitness, anthro-energy intake and psychological variables in identifying the talented male youth field hockey players. 40 male players (age, 14.6 ± 1.2 years) from Terengganu sport academy were evaluated in different tests and measurements.
An empirical study was conducted among 40 contracted Vodacom players from the Golden Lions Rugby Union who completed structured questionnaires prior to a physical testing. The majority of players were between 19 and 31 years. Ninety percent belonged to the white population group and 10% identified themselves ...
Bilir, Fatma Pervin; Sirin, Yeliz
The aim of this study is to figure out profiles of bridge players and analyzing them according to their intelligence areas. The sample of the study is consist of 100 volunteers out of 200 bridge players who have attended "Çukurova open double bridge championship" in Adana, Turkey at February 2016. Data have been collected via…
Koen A.P.M. Lemmink; P.J. Vuijk; S.C. te Wierike; C. Visscher; M.T. Elferink-Gemser; M.C. de Jong; R.M. Malina; E.J. Tromp
Factors affecting repeated sprint ability (RSA) were evaluated in a mixed-longitudinal sample of 48 elite basketball players 14 to 19 years of age (16.1±1.7 years). Players were observed on six occasions during the 2008-2009 and 2009-2010 seasons. Three basketball-specific field tests were
Hawkins, Donna B.; Gruber, Joseph J.
The effect of a season of little league baseball on the self-esteem of 94 pre-adolescent players was investigated. The Coopersmith Self-esteem Inventory and a newly devised Baseball-Self scale were administered. Significant improvements in players' total Self-esteem, Home-Parents and School-Academic scores were found. (Author/PN)
Hubacek, Pavel; Park, Sunoo
In this work we apply methods from cryptography to enable mutually distrusting players to implement broad classes of mediated equilibria of strategic games without trusted mediation. Our implementation uses a pre-play 'cheap talk' phase, consisting of non- binding communication between players...
Full Text Available In the last few decades, numerous experiments have shown that humans do not always behave so as to maximize their material payoff. Cooperative behavior when non-cooperation is a dominant strategy (with respect to the material payoffs is particularly puzzling. Here we propose a novel approach to explain cooperation, assuming what Halpern and Pass call translucent players. Typically, players are assumed to be opaque, in the sense that a deviation by one player in a normal-form game does not affect the strategies used by other players. But a player may believe that if he switches from one strategy to another, the fact that he chooses to switch may be visible to the other players. For example, if he chooses to defect in Prisoner's Dilemma, the other player may sense his guilt. We show that by assuming translucent players, we can recover many of the regularities observed in human behavior in well-studied games such as Prisoner's Dilemma, Traveler's Dilemma, Bertrand Competition, and the Public Goods game.
Stereotype threat has been offered as a potential explanation of differential performance between men and women in some cognitive domains. Questions remain about the reliability and generality of the phenomenon. Previous studies have found that stereotype threat is activated in female chess players when they are matched against male players. I used data from over 5.5 million games of international tournament chess and found no evidence of a stereotype-threat effect. In fact, female players outperform expectations when playing men. Further analysis showed no influence of degree of challenge, player age, nor prevalence of female role models in national chess leagues on differences in performance when women play men versus when they play women. Though this analysis contradicts one specific mechanism of influence of gender stereotypes, the persistent differences between male and female players suggest that systematic factors do exist and remain to be uncovered.
Holmgård, Christoffer; Liapis, Antonios; Togelius, Julian
This paper presents a method for modeling player decision making through the use of agents as AI-driven personas. The paper argues that artificial agents, as generative player models, have properties that allow them to be used as psyhometrically valid, abstract simulations of a human player......’s internal decision making processes. Such agents can then be used to interpret human decision making, as personas and playtesting tools in the game design process, as baselines for adapting agents to mimic classes of human players, or as believable, human-like opponents. This argument is explored...... in a crowdsourced decision making experiment, in which the decisions of human players are recorded in a small-scale dungeon themed puzzle game. Human decisions are compared to the decisions of a number of a priori defined “archetypical” agent-personas, and the humans are characterized by their likeness...
Possin, Katherine L.; Hess, Christopher P.; Huang, Eric J.; Grinberg, Lea T.; Nolan, Amber L.; Cohn-Sheehy, Brendan I.; Ghosh, Pia M.; Lanata, Serggio; Merrilees, Jennifer; Kramer, Joel H.; Berger, Mitchel S.; Miller, Bruce L.; Yaffe, Kristine; Rabinovici, Gil D.
Summary In the aftermath of multiple high-profile cases of chronic traumatic encephalopathy (CTE) in professional American football players, physicians in clinical practice are likely to face an increasing number of retired football players seeking evaluation for chronic neurobehavioral symptoms. Guidelines for the evaluation and treatment of these patients are sparse. Clinical criteria for a diagnosis of CTE are under development. The contribution of CTE vs other neuropathologies to neurobehavioral symptoms in these players remains unclear. Here we describe the experience of our academic memory clinic in evaluating and treating a series of 14 self-referred symptomatic players. Our aim is to raise awareness in the neurology community regarding the different clinical phenotypes, idiosyncratic but potentially treatable symptoms, and the spectrum of underlying neuropathologies in these players. PMID:26336629
Reams, Nicole; Hayward, Rodney A; Kutcher, Jeffrey S; Burke, James F
Lingering neurologic injury after concussion may expose athletes to increased risk if return to play is premature. The authors explored whether on-field performance after concussion is a marker of lingering neurologic injury. Retrospective cohort study on 1882 skill-position players who played in the National Football League (NFL) during 2007-2010. Players with concussion based on the weekly injury report were compared with players with other head and neck injuries (controls) on measures of on-field performance using Football Outsiders' calculation of defense-adjusted yards above replacement (DYAR), a measure of a player's contribution controlling for game context. Changes in performance, relative to a player's baseline level of performance, were estimated before and after injury using fixed-effects models. The study included 140 concussed players and 57 controls. Players with concussion performed no better or worse than their baseline on return to play. However, a decline in DYAR relative to their prior performance was noted 2 wk and 1 wk before appearing on the injury report. Concussed players performed slightly better than controls in situations where they returned to play the same week as appearing on the injury report. On return, concussed NFL players performed at their baseline level of performance, suggesting that players have recovered from concussion. Decline in performance noted 2 wk and 1 wk before appearing on the injury report may suggest that concussion diagnosis was delayed or that concussion can be a multihit phenomenon. Athletic performance may be a novel tool for assessing concussion injury and recovery.
Shanley, Ellen; Rauh, Mitchell J; Michener, Lori A; Ellenbecker, Todd S
Participation in high school sports has grown 16.1% over the last decade, but few studies have compared the overall injury risks in girls' softball and boys' baseball. To examine the incidence of injury in high school softball and baseball players. Cohort study. Greenville, South Carolina, high schools. Softball and baseball players (n = 247) from 11 high schools. Injury rates, locations, types; initial or subsequent injury; practice or game setting; positions played; seasonal trends. The overall incidence injury rate was 4.5/1000 athlete-exposures (AEs), with more injuries overall in softball players (5.6/1000 AEs) than in baseball players (4.0/1000 AEs). Baseball players had a higher initial injury rate (75.9/1000 AEs) than softball players (66.4/1000 AEs): rate ratio (RR) = 0.88, 95% confidence interval (CI) = 0.4, 1.7. The initial injury rate was higher than the subsequent injury rate for the overall sample (P softball (P Softball players were more likely to be injured in a game than were baseball players (RR = 1.92, 95% CI = 0.8, 4.3). Most injuries (77%) were mild (3.5/1000 AEs). The upper extremity accounted for the highest proportion of injuries (63.3%). The incidence of injury for pitchers was 37.3% and for position players was 15.3%. The rate of injury was highest during the first month of the season (7.96/1000 AEs). The incidence of injury was low for both softball and baseball. Most injuries were minor and affected the upper extremity. The injury rates were highest in the first month of the season, so prevention strategies should be focused on minimizing injuries and monitoring players early in the season.
Monezi, Lucas Antônio; Magalhães, Thiago Pinguelli; Morato, Márcio Pereira; Mercadante, Luciano Allegretti; Furtado, Otávio Luis Piva da Cunha; Misuta, Milton Shoiti
In this study, we aimed to analyse goalball players time-motion variables (distance covered, time spent, maximum and average velocities) in official goalball match attacks, taking into account the attack phases (preparation and throwing), player position (centres and wings) and throwing techniques (frontal, spin and between the legs). A total of 365 attacks were assessed using a video based method (2D) through manual tracking using the Dvideo system. Inferential non-parametric statistics were applied for comparison of preparation vs. throwing phase, wings vs. centres and, among the throwing techniques, frontal, spin and between the legs. Significant differences were found between the attack preparation versus the throwing phase for all player time-motion variables: distance covered, time spent, maximum player velocity and average player velocity. Wing players performed most of the throws (85%) and covered longer distances than centres (1.65 vs 0.31 m). The between the legs and the spin throwing techniques presented greater values for most of the time-motion variables (distance covered, time spent and maximum player velocity) than did the frontal technique in both attack phases. These findings provide important information regarding players' movement patterns during goalball matches that can be used to plan more effective training.
Skinner, Brian; Guy, Stephen J
Player tracking data represents a revolutionary new data source for basketball analysis, in which essentially every aspect of a player's performance is tracked and can be analyzed numerically. We suggest a way by which this data set, when coupled with a network-style model of the offense that relates players' skills to the team's success at running different plays, can be used to automatically learn players' skills and predict the performance of untested 5-man lineups in a way that accounts for the interaction between players' respective skill sets. After developing a general analysis procedure, we present as an example a specific implementation of our method using a simplified network model. While player tracking data is not yet available in the public domain, we evaluate our model using simulated data and show that player skills can be accurately inferred by a simple statistical inference scheme. Finally, we use the model to analyze games from the 2011 playoff series between the Memphis Grizzlies and the Oklahoma City Thunder and we show that, even with a very limited data set, the model can consistently describe a player's interactions with a given lineup based only on his performance with a different lineup.
Full Text Available Player tracking data represents a revolutionary new data source for basketball analysis, in which essentially every aspect of a player's performance is tracked and can be analyzed numerically. We suggest a way by which this data set, when coupled with a network-style model of the offense that relates players' skills to the team's success at running different plays, can be used to automatically learn players' skills and predict the performance of untested 5-man lineups in a way that accounts for the interaction between players' respective skill sets. After developing a general analysis procedure, we present as an example a specific implementation of our method using a simplified network model. While player tracking data is not yet available in the public domain, we evaluate our model using simulated data and show that player skills can be accurately inferred by a simple statistical inference scheme. Finally, we use the model to analyze games from the 2011 playoff series between the Memphis Grizzlies and the Oklahoma City Thunder and we show that, even with a very limited data set, the model can consistently describe a player's interactions with a given lineup based only on his performance with a different lineup.
Full Text Available The purpose of this study was to determine differences in bone mineral density (BMD among adolescent female tennis players (TPs and nontennis players (NTPs and to assess body composition as a predictor variable of BMD. Nineteen female TPs and 19 female NTPs, ages 14 to 18 years, participated in this study. Lumbar spine, total hip, femoral neck, forearms BMD, and body composition were assessed using dual-energy X-ray absorptiometry (DXA. Lumbar spine and total hip BMD measurements for TP were greater than NTP. However, these differences were not statistically significant (=0.37 and 0.12, resp.. TP had significantly greater femoral neck BMD than NTPs (=0.02. This difference might play an important role in preventing osteoporosis and decreasing the risk of fractures at the hip later in life.
This article attempts to demonstrate that the family is a key player in the athlete's development and performance, sometimes invisible, but often all too visible. The practice of clinical sport psychology is enriched by a family-based orientation to the assessment and treatment of athletes. Creating a workable family system is a challenge for parents. They have many difficult decisions to make, and are often without support and direction in making those choices. Sport psychiatrists and psychologists can be helpful to parents as well as athletes by using family-based assessments and treatment interventions that provide education, challenge, and support as they negotiate the tasks and transitions in the family life cycle.
José António Ribeiro Maia
Full Text Available The characteristics of physique have been the subject of several studies in sport sciences because high-level competitive sports place maximum demands on the physical constitution of players. Furthermore, the specifi c function performed by a player in a game may be related to a particular modality. The goals of this study were: (1 to describe and to compare, from a somatic point of view, the physiques of 71 female volleyball players at beginner levels A and B (aged 12-14 years; and (2 to identify the components of somatic structure that best differentiate the athletics by level of experience. In order to evaluate the players’ somatic structure,we performed 21 measurements including: weight and height, diameters, circumferences, upper and lower limb measurements and skinfolds thicknesses. Discriminant function analysis (DFA was used to identify the power of variables classifi cation. No difference was found in physique between level A and level B players. They were classifi ed by somatotype as mesomorphic endomorphs (A = 4.76 - 3.78 - 1.85; and B = 4.37 - 4.02 - 1.88. RESUMO As características morfológicas têm sido objeto de vários estudos em Ciências Desporto, pelo fato de o fenômeno do desporto de alta competição exigir o máximo da estrutura física dos atletas e pela expectativa da função que o atleta desempenha em jogo. O presente estudo teve como objetivo: (1 descrever e comparar, do ponto de vista somático, a estrutura morfológica de 71 atletas de voleibol do sexo feminino dos escalões de formação A e B (entre os 12 e 14 anos de idade; (2 identifi car os componentes da estrutura somática que melhor diferenciam as atletas de níveis distintos. Para a avaliação da estrutura somática das atletas foram efetuadas 21 avaliações, incluindo além do peso e altura, comprimento dos membros, perímetros, diâmetros e pregas de adiposidade subcutâneas. Com o intuito de verifi car o poder discriminatório das variáveis na
Full Text Available Purpose – to analyze gamification, as the method for promoting creativity in individual and collective levels with the respect to player types.Design/methodology/approach – This research serves as a general review/viewpoint which seeks to examine collective creativity as a phenomenon and gamification as the tool for promoting individual and collective creativity. The paper is based on the comparative analysis of scientific literature and related sources from game design, psychology, business and entertainment.Findings – Although the gamification is gaining more public attention, there is a lack of studies which would reveal its relations in fostering individual and collective creativity. One of the main goals of any gamified content is to raise the engagement into activities in non-game contexts. The objective of creative work is to come up with some ideas, methods or tools which would be significantly new and innovative in the case of a certain issue. The theory of “flow” is used widely in explaining the working principles of gamification. In this state, the information absorption rates are increased and the group or individual is immersed into performed activities. This may lead to prolonged periods while accumulating knowledge, and thus, improving creative capabilities in the specific domain. However, creative performance in different fields has various approaches. It is also related to personal characteristics. The success of gamification is also dependent on the types of “players” which participate in the activity. Having the common picture of personality type in creative performance and in game based tasks may allow creating gamification strategy for optimal engagement into creative work according to the features of a person.Research limitations/implications – There are very few empirical studies which would support correlation between experiencing the “flow” state and a raise of creativity. The idea of unified
Sanchis-Moysi, Joaquin; Idoate, Fernando; Izquierdo, Mikel; Calbet, Jose A. L.; Dorado, Cecilia
Purpose To determine the volume and degree of asymmetry of iliopsoas (IL) and gluteal muscles (GL) in tennis and soccer players. Methods IL and GL volumes were determined using magnetic resonance imaging (MRI) in male professional tennis (TP) and soccer players (SP), and in non-active control subjects (CG) (n = 8, 15 and 6, respectively). Results The dominant and non-dominant IL were hypertrophied in TP (24 and 36%, respectively, Psoccer players had similar volumes in both sides (P = 0.87). The degree of side-to-side asymmetry decreased linearly from the first lumbar disc to the pubic symphysis in TP (r = −0.97, PSoccer and CG had similar GL volumes in both sides (P = 0.11 and P = 0.19, for the dominant and contralateral GL, respectively). GL was asymmetrically hypertrophied in TP. The non-dominant GL volume was 20% greater in TP than in CG (Psoccer is associated to a symmetric hypertrophy of IL. Gluteal muscles are asymmetrically hypertrophied in TP, while SP display a similar size to that observed in controls. It remains to be determined whether the different patterns of IL and GL hypertrophy may influence the risk of injury. PMID:21829539
Manuel Jacob Sierra-Díaz
Full Text Available Grouping people according to chronological age is popular in fields such as education and sport. Athletes who are born in the first months of the year usually have cognitive and physical development differences in contrast to those born in the last months of the same year. That is why competitive teams tend to select older players more often than youngsters. Age differences between athletes born in the same year as well as an over-representation of older players are known as the Relative Age Effect. This effect is extensively described in young and elite team sports such as basketball, volleyball or, ice-hockey, as well as in soccer. The purpose of this study is to examine the state-of-the-art of the Relative Age Effect in youth and elite soccer players. This review summarizes recent research articles on the Relative Age Effect related to competitive soccer from 2010 to 2016. The systematic literature search was conducted in four databases: SPORTDiscus, Medline, EBSCO host and Google Scholar. Although causes and final solutions have not been clearly achieved yet, it is necessary to continue investigating this phenomenon in order to provide a starting point for future research.
GOH PIN SIANG
Full Text Available The purpose of this study is to advance the understanding of volleyball players’ purchase intention toward sport shoes by investigating the relationship between the independent variables (endorsement, advertising, pricing and electronic word-of-mouth and purchase intention. Descriptive research and causal research will be used as the research design, thus questionnaire and experimentation will be used to obtain data. Primary data in this study is attained by distributing the questionnaire to the Malaysian volleyball players throughout several volleyball tournament venues in Malaysia. The experiment will be conducted by comparing two groups of respondents, including volleyball players and non-volleyball players. This study is limited to several independent variables such as endorsement, advertising, pricing and electronic word-of-mouth. This study is significant for marketers for solving the challenges faced in the sport industry. It also helps to identify consumers’ purchase preferences for sport shoes. The marketer would understand more about their targeted customers’ intentions to purchase, thus the sport industry related with sport marketing in Malaysia might gain more profit.
Full Text Available This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points.
Gomez, Gabriel; Herrera López, Patricia; Link, Daniel; Eskofier, Bjoern
This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points. PMID:25426936
Novak, Dario; Vucetić, Vlatko; Zugaj, Sanja
The primary purpose of this study was to determine differences between elite athletes and tennis players in order to provide a clearer picture regarding the energy demands in modern tennis. Forty-eight (48) athletes and 24 tennis players from Croatian national leagues were compared in morphological and physiological parameters of an all-out incremental treadmill test with gas exchange measurements. Tennis players' HRmax (192.96+/-7.75 bpm) shows values that are most different to 400-meters sprinters (200.13+/-6.95 bpm). Maximum running speed of tennis players on the treadmill (vmax) is no different with the speed achieved by sprinters, while there are significant differences among other athletes. Values in running speed at anaerobic threshold (vAnT) show no statistically significant difference with the values for athlete sprinters and 400-m sprinters. Values of RvO2max for tennis players indicate significant similarities with athlete sprinters and 400-m sprinters while the values of RvO2AnT are nearly identical with the values for sprinters and show no statistically significant differences (psprint endurance in tennis players. Knowing these characteristics is the basis for planning and implementing training systems that will enable the increase and optimal usage of energy capacities of tennis players in possibly improving sports results.
Fryer, Ashley Marie; Tenenbaum, Gershon; Chow, Graig M
This study was aimed at examining how basketball players view unexpected performance errors in basketball, and under what conditions they perceive them as choking. Fifty-three basketball players were randomly assigned into 2 groups (game half) to evaluate the linkage between performance decline and choking as a function of game-time, score gap and game half. Within each group, players viewed 8 scenario clips, which featured a different player conducting an error, and subsequently rated the extent of performance decline, the instance of choking and the salience of various performance attributions regarding the error. The analysis revealed that choking was most salient in the 2nd half of the game, but an error was perceived as choking more saliently in the beginning of the 2nd half. This trend was also shown for players' perception of performance decline. Players' ratings of the attributions assigned to errors, however, revealed that during the end of the 2nd half, time pressure and lack of concentration were the causes of errors. Overall, the results provide evidence towards a conceptual framework linking performance decline to the perception of choking, and that errors conducted by players are perceived as choking when there is not a salient reason to suggest its occurrence.
Guss, Michael S; Begly, John P; Ramme, Austin J; Hinds, Richard M; Karia, Raj J; Capo, John T
Background: The aim was to determine whether players in the National Basketball Association (NBA) who sustain metacarpal fractures demonstrate decreased performance upon return to competition when compared with their performance before injury and that of their control-matched peers. Methods: Data for 32 NBA players with metacarpal fractures incurred over 11 seasons (2002-2003 to 2012-2013) were obtained from injury reports, press releases, and player profiles (www.nba.com and www.basketballreference.com). Player age, body mass index (BMI), position, shooting hand, number of years in the league, and treatment (surgical vs nonsurgical) were recorded. Individual season statistics for the 2 seasons immediately prior to injury and the 2 seasons after injury, including player efficiency rating (PER), were obtained. Thirty-two controls matched by player position, age, and performance statistics were identified. A performance comparison of the cohorts was performed. Results: Mean age at the time of injury was 27 years with an average player BMI of 24. Players had a mean 5.6 seasons of NBA experience prior to injury. There was no significant change in PER when preinjury and postinjury performances were compared. Neither injury to their shooting hand nor operative management of the fracture led to a decrease in performance during the 2 seasons after injury. When compared with matched controls, no significant decline in performance in PER the first season and second season after injury was found. Conclusion: NBA players sustaining metacarpal fractures can reasonably expect to return to their preinjury performance levels following appropriate treatment.
Govind B. Taware
Full Text Available Background: Ball games require comprehen-sive ability including physical, technical, men-tal and tactical abilities. Among them, physicalabilities of players exert marked effects on theskill of the players themselves and the tacticsof the team. Therefore players must have thephysical abilities to meet the demand of thesport. Volleyball is one of the most popularlyplayed games in the world. Unfortunately, thelevel of performance of the Indian volleyballplayers lags far behind the international stan-dards. Aim of the Study: The present study wasaimed to assess flexibility, muscular endurance,power and cardio-respiratory endurance of vol-leyball players and to compare the results withage matched controls. Also, to compare thefindings of the volleyball players with that ofthe international norms from the available lit-erature and to make some suggestions for theimprovement in their performance level. Ma-terial and Methods: The study was carried outin 40 male volleyball players aged between 17to 26 years and 40 ages matched male controls.Physical fitness parameters namely flexibility,muscular endurance, power and cardio-respi-ratory endurance were measured, data was ana-lyzed using unpaired t-test. Results: It was ob-served that all physical fitness parameters weresignificantly more in players as compared totheir aged-matched controls but when values ofthe subjects were compared to internationalstandards; our subjects were behind the recom-mended norms for the elite volleyball players.Conclusion: The volleyball players have moreadvantage of flexibility muscular endurance,power and cardio-respiratory endurance.
Davis, Jon K; Baker, Lindsay B; Barnes, Kelly; Ungaro, Corey; Stofan, John
Numerous studies have reported on the thermoregulation and hydration challenges athletes face in team and individual sports during exercise in the heat. Comparatively less research, however, has been conducted on the American Football player. Therefore, the purpose of this article is to review data collected in laboratory and field studies and discuss the thermoregulation, fluid balance, and sweat losses of American Football players. American Football presents a unique challenge to thermoregulation compared with other sports because of the encapsulating nature of the required protective equipment, large body size of players, and preseason practice occurring during the hottest time of year. Epidemiological studies report disproportionately higher rates of exertional heat illness and heat stroke in American Football compared with other sports. Specifically, larger players (e.g., linemen) are at increased risk for heat ailments compared with smaller players (e.g., backs) because of greater body mass index, increased body fat, lower surface area to body mass ratio, lower aerobic capacity, and the stationary nature of the position, which can reduce heat dissipation. A consistent finding across studies is that larger players exhibit higher sweating rates than smaller players. Mean sweating rates from 1.0 to 2.9 L/h have been reported for college and professional American Football players, with several studies reporting 3.0 L/h or more in some larger players. Sweat sodium concentration of American Football players does not seem to differ from that of athletes in other sports; however, given the high volume of sweat loss, the potential for sodium loss is higher in American Football than in other sports. Despite high sweating rates with American Football players, the observed disturbances in fluid balance have generally been mild (mean body mass loss ≤2 %). The majority of field-based studies have been conducted in the northeastern part of the United States, with limited
This document reviews 338 players in the French photovoltaic industry. Each player can be the owner of a photovoltaic power plant, or its operator, or the manufacturer of photovoltaic systems, or the manufacturer of components involved in photovoltaic systems, or the equipment wholesaler, or the designer of photovoltaic projects, or the photovoltaic system installer. For each player some pieces of information are gathered: a brief history of the enterprise, the enterprise activity, its staff, its turnover, its main achievements and its prospects. (A.C.)
Maroon, Joseph C; Mathyssek, Christina M; Bost, Jeffrey W; Amos, Austin; Winkelman, Robert; Yates, Anthony P; Duca, Mark A; Norwig, John A
By maintaining phosphate and calcium homeostasis, vitamin D is critical for bone health and possibly physical performance. Hence, vitamin D is important to athletes. Few studies have investigated vitamin D levels in relation to fractures and performance in athletes, and no published study has included a multiracial sample of professional American football players. To assess vitamin D levels, including the prevalence of vitamin D deficiency/insufficiency, in professional American football players and to evaluate the association of vitamin D levels with race, fracture history, and the ability to obtain a contract position, which may be a marker for athletic performance. Cohort study; Level of evidence, 3. Serum vitamin D levels of 80 professional football players from a single team in the National Football League were obtained during the 2011 off-season (mean age, 26.5±3.7 years; black, n=67 [84%]). These levels were used to compare injury reports from the 2011-2012 and 2012-2013 seasons. Statistical analyses were performed to test if vitamin D levels were related to race, fracture history, and the ability to obtain a contract position. Mean vitamin D level was 27.4±11.7 ng/mL, with significantly lower levels for black players (25.6±11.3 ng/mL) versus white players (37.4±8.6 ng/mL; F 1,78=13.00, P=.001). All athletes who were vitamin D deficient were black. When controlling for number of professional years played, vitamin D levels were significantly lower in players with at least 1 bone fracture when compared with no fractures. Players who were released during the preseason because of either injury or poor performance had significantly lower vitamin D levels than did players who played in the regular season. Black professional football players have a higher rate of vitamin D deficiency than do white players. Furthermore, professional football players with higher vitamin D levels were more likely to obtain a contract position in the National Football League
Full Text Available The designed player uses the Freescale Company’s MK20DX128VLH7 as the core control ship, and its hardware platform is equipped with VS1003 audio decoder, OLED display interface, USB interface and SD card slot. The player uses the open source embedded real-time operating system μC/OS-II, Freescale USB Stack V4.1.1 and FATFS, and a graphical user interface is developed to improve the user experience based on CGUI. In general, the designed WAV audio player has a strong applicability and a good practical value.
Full Text Available The purpose of the study was to investigate what factors affect basketball players in the transition from junior and amateur to senior and professional sport respectively. The study was a qualitative research which uses a semi-structured interview to get the data. There were interviewed five Spanish basketball players who were starting playing in a team of Basketball Club Association (C.B.A.. The results showed that the participants face several changes both in the sport and in the life outside sport. At the same time, the results indicated the existence of several coping strategies that help the player in his career transition.
With the advancement of sports medicine in the past decade, hockey players all over the world are always trying to find a competitive edge through nutritional education and proper eating. It is very common to find young junior players looking to make the jump into the professional game always trying to find ways to get bigger and add lean muscle mass, likewise, there are always players looking to drop a few pounds while keeping their muscle mass. Research has proven that through proper educat...
Chen, Lily Shui-Lien; Tu, Hill Hung-Jen; Wang, Edward Shih-Tse
The DFC Intelligence predicts worldwide online game revenues will reach $9.8 billion by 2009, making online gaming a mainstream recreational activity. Understanding online game player personality traits is therefore important. This study researches the relationship between personality traits and life satisfaction in online game players. Taipei, Taiwan, is the study location, with questionnaire surveys conducted in cyber cafe shops. Multiple regression analysis studies the causal relationship between personality traits and life satisfaction in online game players. The result shows that neuroticism has significant negative influence on life satisfaction. Both openness and conscientiousness have significant positive influence on life satisfaction. Finally, implications for leisure practice and further research are discussed.
Meir, Rudi; Newton, Robert; Curtis, Edgar; Fardell, Matthew; Butler, Benjamin
Australian and English professional rugby players completed various physical fitness performance tests to determine differences when grouping players into three different rugby positional categories. Results found minimal differences in test scores on the basis of players' specific positions on a team, however, when players were grouped according…
Michalsik, L B; Aagaard, Per; Madsen, K
The purpose of this study was to determine the physical demands and match-induced impairments in physical performance in male elite Team Handball (TH) players in relation to playing position. Male elite TH field players were closely observed during 6 competitive seasons. Each player (wing players...
De Jaegher, K.J.M.
In the two-player electronic mail game (EMG), as is well-known, the probability of collective action is lower the more confirmations and re-confirmations are made available to players. In the multi-player EMG, however, as we show players may coordinate on equilibria where they require only few of
Full Text Available The present study aimed to verify whether body somatotype was indicative of competitive success in female utsal (indoor soccer players. One hundred and twelve players (22.1 ± 5.4 years; 58.4 ± 6.9 kg; 161.8 ± 6.2 cm, from ten teams and seven different states, had participated in a national competition. The anthropometric date was analyzed using one-way ANOVA for repeated measures. The somatotype dispersion distance was applied to compare somatotypes between the champion team (reference and the other teams (from 2nd to 10th position. Anthropometric characteristics didnot differ signifi cantly among teams. The results showed that the endomorphic component was predominant in relation to the mesomorphic and ectomorphic component, irrespective of a team’s ranking at the end of the competition. Therefore, the body somatotypes of female futsal teams cannot be considered as indicative of their competitive success. Resumo O presente estudo teve como objetivo verificar se o somatotipo corporal pode ser considerado um indicador de desempenho em atletas de futsal feminino, levando em consideração a classifi cação das equipes em uma competição ofi cial. A população foi constituída de 112 jogadoras (22,1 ± 5,4 anos; 58,4 ± 6,9 kg; 161,8 ± 6,2 cm, pertencentes a dez equipes de sete estados que disputavam a competição. Os dados antropométricos foram analisados mediante ANOVA one-way para medidas repetidas. Para comparar o somatotipo da campeã (referência com o das demais classificadas (2ª a 10ª colocação na competição, recorreu-se ao cálculo da distância de dispersão do somatotipo. As características antropométricas das equipes não diferiram estatisticamente. Os resultados revelaram que a endomorfia foi predominante em relação à mesomorfia e ectomorfia, independente da classificação das equipes na competição. Neste caso, a classifi cação somatotipológico apresentada pela equipe vencedora, ou qualquer outra neste
Castro-Sepúlveda, Mauricio; Astudillo, Sebastian; Álvarez, Cristian; Zapata-Lamana, Rafael; Zbinden-Foncea, Hermann; Ramírez-Campillo, Rodrigo; Jorquera, Carlos
there is a lack of studies concerning hydration status before training in professional soccer player. to describe hydration status before regular training practices in professional soccer players. a total of 156 male soccer players (age 25.4 ± 5.2 y) from six professional Chilean clubs were included. No hydration or food intake recommendations were made before experiment, with the aim to assess hydration status under athlete's regular "real" conditions. Body mass, height and urine specific gravity (USG) measurements were performed before training practices. 98% of athletes showed dehydration (between moderate and severe) before regular training practices. dehydration is the most prevalent hydration status in professional Chilean soccer players before training, which may negatively affect athlete's performance and may increase their risk of heat-related injuries. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
Hampshire, Adam; MacDonald, Alex; Owen, Adrian M.
Recent research has raised concerns about the long-term neurological consequences of repetitive concussive and sub-concussive injuries in professional players of American Football. Despite this interest, the neural and psychological status of retired players remains unknown. Here, we evaluated the performances and brain activation patterns of retired National Football League players (NFL alumni) relative to controls using an fMRI-optimised neuropsychological test of executive function. Behaviourally, the NFL alumni showed only modest performance deficits on the executive task. By contrast, they showed pronounced hyperactivation and hypoconnectivity of the dorsolateral frontal and frontopolar cortices. Critically, abnormal frontal-lobe function was correlated with the number of times that NFL alumni reported having been removed from play after head injury and was evident in individual players. These results support the hypothesis that NFL alumni have a heightened probability of developing executive dysfunction and suggest that fMRI provides the most sensitive biomarker of the underlying neural abnormality.
South African Journal for Research in Sport, Physical Education and ... rugby union and American football players in different playing positions have been reported. These differences are believed to be the result of the specific demands of ...
Psycho-social attributes of elite African women volleyball players. ... 78% of them were influenced by family members to play volleyball, 81% continued to play the game due to success, and 64% envisaged that ... AJOL African Journals Online.
." These methods for constructing procedural personas are then integrated with existing procedural content generation systems, acting as critics that shape the output of these systems, optimizing generated content for different personas and by extension, different kinds of players and their decision making styles......How can player models and artificially intelligent (AI) agents be useful in early-stage iterative game and simulation design? One answer may be as ways of generating synthetic play-test data, before a game or level has ever seen a player, or when the sampled amount of play test data is very low....... This thesis explores methods for creating low-complexity, easily interpretable, generative AI agents for use in game and simulation design. Based on insights from decision theory and behavioral economics, the thesis investigates how player decision making styles may be defined, operationalised, and measured...
Conclusions: The 8-week combined jump and ball throwing training can significantly improve muscular performance in young female volleyball players. These findings may be useful for all physical education teachers and volleyball coaches.
Yannakakis, Georgios; Hallam, John
A methodology for optimizing player satisfaction in games on the "playware" physical interactive platform is demonstrated in this paper. Previously constructed artificial neural network user models, reported in the literature, map individual playing characteristics to reported entertainment...
... commonly injured. Keywords: Epidemiology, soccer injuries, youth ... fun and enjoyment while burning up calories especially when electronic devices ... ture on female soccer players has also grown significant- ly9,10. In the last decade, ...
Heisterberg, Mette F; Fahrenkrug, Jan; Krustrup, Peter
of the season. Leucocytes decreased with increased physical training. Lymphocytes decreased at the end of the season. VO2max decreased towards the end of the season whereas no significant changes were observed in the IE2 test.The regular blood samples from elite soccer players reveal significant changes......ABSTRACT: The aim of this study was to make a comprehensive gathering of consecutive detailed blood samples from professional soccer players, and to analyze different blood parameters in relation to seasonal changes in training and match exposure.Blood samples were collected five times during a six...... months period and analyzed for 37 variables in 27 professional soccer players from the best Danish league. Additionally, players were tested for body composition, VO2max and physical performance by the Yo-Yo intermittent endurance sub-max test (IE2).Multiple variations in blood parameters occurred during...
Full Text Available Swimming preparation of water-polo players is the basic factor of victory of command. There are a few variants of development of speed swimming preparation. The effective pedagogical mean of stimulation of speed qualities is brief exercises at the end of employments after long aerobic work. The purpose of work is an improvement of method of speed preparation of skilled water-polo players. 26 skilled water-polo players (MS -14 and KMS - 12 took part in an experiment in age from 21 to 32 years. The results of correction of structure of training employment are in-process presented in micro cycle. They are directed on the improvement of speed qualities of water-polo players.
Netball, as a team sport, is an interval- ... intensity, short bursts of movement and less intense recovery periods. ... tiveness of a training programme can be evaluated. Feedback ..... the Boland players also had a higher body fat percentage than.
Full Text Available Considerable importance for the control system, selection and orientation of the players on the stage long-term preparation plays a selection of effective methods of testing the various components of functional fitness athlete for timely, objective information about the players. The use of reliable scientific methods of effective monitoring of the athlete contributes to the further improvement of skills, increase athletic achievements. The purpose of this article is to describe and summarize modern methods of diagnosis and development of aerobic component of operational preparedness players qualifications. This article describes methods that actively and effectively used in leading European football teams. Specifically Yo-Yo test, test Shuttle (beep-test, Bangsbo test, test Hoff-Helgerud, test Conconi, Wingate-test. These tests have a high level of reliability and security mechanisms for assessing aerobic power players.
Rajkumar S HARMA
Full Text Available Pr eferences for specific coaching behaviours of male and female Badminton players were measured by the modified and revised Leadership Scale for Sport. Eighty two (Males=61, Females=21 badminton players were selected from amongst the players representing th eir respective university teams in East - zone Inter - university Badminton (Men/Women tournaments held at Bilaspur (CG. The present investigation noted the statistically significant differences among East - zone Inter - university level male as well as female B adminton player’s preferences for specific coaching behaviour. Differences were not observed between male and female badminton players in all the dimensions together of specific coaching behaviours of preferred leadership. It is recommended that coaches a lign their coaching style to meet the needs of their teams.
Reid, Machar; Morris, Craig
In men's professional tennis, players aspire to hold the top ranking position. On the way to the top spot, reaching the top 100 can be seen as a significant career milestone. National Federations undertake extensive efforts to assist their players to reach the top 100. However, objective data considering reasonable ranking yardsticks for top 100 success in men's professional tennis are lacking. Therefore, it is difficult for National Federations and those involved in player development to give empirical programming advice to young players. By taking a closer look at the ranking history of professional male tennis players, this article tries to provide those involved in player development a more objective basis for decision-making. The 100 names, countries, birthdates and ranking histories of the top 100 players listed in the Association of Tennis Professionals (ATP) at 31 December 2009 were recorded from websites in the public domain. Descriptive statistics were reported for the ranking milestones of interest. Results confirmed the merits of the International Tennis Federation's junior tour with 91% of the top 100 professionals earning a junior ranking, the mean peak of which was 94.1, s=148.9. On average, top 100 professionals achieved their best junior rankings and earned their first ATP point at similar ages, suggesting that players compete on both the junior and professional tours during their transition. Once professionally ranked, players took an average 4.5, s=2.1 years to reach the ATP top 100 at the mean age of 21.5, s=2.6 years, which contrasts with the mean current age of the top 100 of 26.8, s=3.2. The best professional rankings of players born in 1982 or earlier were positively related to the ages at which players earned their first ATP point and then entered the top 100, suggesting that the ages associated with these ranking milestones may have some forecasting potential. Future work should focus on the change in top 100 demographics over time as well
Varghese C. Antony
Full Text Available The study aims to compare the mental toughness attributes between medalist and non-medalist badminton players and between male and female players. Participants were 15 male and 15 female badminton players aged between 13-19 years (M= 15.71, SD=2.82. Mental toughness questionnaire of Tiwari and Sharma was administered and the data were analyzed by using descriptive statistics and t-test. Medalist players have exhibited higher mean values on self-confidence, attention control, motivation and goal setting attributes. Overall mental toughness of medalists was higher 180.80±17.15 than non-medalists 170.25±20.10. Comparison analysis showed significant difference between medalists and non-medalists on mental toughness attributes: Self-confidence (SCO: p=0.001<0.05, medalists scored (M±SD=31.33±2.10 higher than non-medalists; motivation (MOT: p=0.006<0.05, medalist scored higher (M±SD=33.50±4.07; goal setting (GSE: p=0.044<0.05, medalists scored significantly higher (M±SD=33.55±4.11 than non-medalists. Other attributes did not show any significant difference between medalist and non-medalist players. When compared with gender, no significant difference was observed on mental toughness attributes except attention control (ATNCON: p=0.044<0.05, female players scored (M±SD=38.97±3.08 higher than male players. The findings confirm that mental toughness is a desired attribute which differentiates a medalist and non-medalist player. Connaughton et al., (2007 stated that elite competitive athletes possess better mental toughness. Medalist players displayed better self-confidence than the non-medalists as supported by Kuan and Roy (2007, Loehr (1986. Motivation helps players to achieve their best and enhance mental toughness (Connaughton et al., 2008; Mohammad et al., 2009. Goal setting determines successful performance Weinberg and Weigand (1993, Weinberg (2003. It was concluded that medalist badminton players showed better mental toughness
client plug-ins currentl:v only exist for C++, . Java . and Python. Player is designed a.’:i a. client-server architecture in which robots running Player...I 0.. double -1.0272 angular velocity ;.... ~ va t- <ll ~ 38 2D 73 65 * :>, ""’::!’ ell I 0, +’ 00 00 00 01 uint8 t state 1 motor state v .S 2.5
Playing computer games consists of an interplay between the player's body movements in the physical world and the agency of game characters in the game's virtual environment with the controller as a mediator remediating the movements of the player in physical space into the actions of the avatar ...... both the avatars bodily movements, it also represents the very tool which the avatar is using when performing its actions, e.g. a sword or a tennis catcher....
Chang, Ju-Hui; Zhang, Hongxia
The online game market has been growing rapidly and has received an increasing amount of attention in recent years. The results of a survey conducted in China to explore online game players' attitude formation reveal that (a) the online game player's level of materialism positively influences the motivation for playing, (b) motivation positively influences attitude toward online games, and (c) motivation fully mediates the effects of materialism on attitude.
One result of opening up the European gas market to competition has been to increase the number and diversity of the players involved, whether producers, suppliers or electric utilities. However, while the gas on offer is still controlled by a handful of market players given the increasing importance of state-owned companies from exporting countries outside Europe, the downstream gas sector continues to show a strong concentration of incumbent operators seeking a dominant position in the supply of gas. (author)
Full Text Available Introduction. The aims of the present study were to determine the activity profiles of a large sample of Polish Premier League soccer players during elite-standard soccer matches depending on their position on the pitch and the intensity range of physical activity. Material and methods. The study sample comprised 1,178 players in 5 outfield positions: external defenders (ED, n = 289, central defenders (CD, n = 307, central midfield players (CM, n = 327, external midfield players (EM, n = 152, and forwards (F, n = 103. Altogether, 81 Polish League games held during four domestic seasons (2010-2011, 2011-2012, 2012-2013, and 2013-2014 were used in the analysis. A semi-automatic computerised player tracking system (Amisco Pro®, version 1.0.2, Nice, France was applied to create the match activity profiles of the teams. Results. The results of statistical analysis revealed that the average total distance covered by all the players (n = 1,178 was 11,313 ± 852 m. With respect to the players’ position on the pitch, the central midfielders travelled the longest average distance (11,894 ± 765 m during the game. The longest distance was covered in the V1 intensity range (62%, followed by V2 (15%, V3 (10%, V4 (8%, V5 (3%, and V6 (2%. Conclusions. The objective of this study was to verify the differences among playing positions and to quantify the demands placed on elite Polish soccer players in each individual position during match play. While analysing elite-level match play in terms of the overall distance covered in different categories of intensity, we found a number of statistically significant differences between different playing positions. The data presented in this study can be regarded as norms for elite soccer players, serve for present and future comparison, and represent the scientific basis for developing position-specific conditioning/training protocols in soccer.
Eirale, Cristiano; Tol, Johannes L; Whiteley, Rod
Goalkeepers have a specific physiological and biomechanical profile including hip loading with increased frontal plane kinetics and explosive side jumps. The aim of this study is to analyze the injury incidence in professional goalkeepers and to compare this with field players.......Goalkeepers have a specific physiological and biomechanical profile including hip loading with increased frontal plane kinetics and explosive side jumps. The aim of this study is to analyze the injury incidence in professional goalkeepers and to compare this with field players....
Novak, Dario; Vučetić, Vlatko; Žugaj, Sanja
The primary purpose of this study was to determine differences between elite athletes and tennis players in order to provide a clearer picture regarding the energy demands in modern tennis. Forty-eight (48) athletes and 24 tennis players from Croatian national leagues were compared in morphological and physiological parameters of an all-out incremental treadmill test with gas exchange measurements. Tennis players’ HRmax (192.96±7.75 bpm) shows values that are most different to 400-meters spri...
Chevalier, J.M.; Salaun, D.
The changes that are being brought in the forms of organization of the power industry lead to a global restructuring of the industry. Traditional players are forced to redefine their strategies concerning vertical and horizontal integration and also diversification. They tend to internationalize their business but they are facing aggressive new-comers. The future structure of the industry is not yet determined but there will be a great number of very different corporate players. (authors). 1 fig
Anagnostou , Kostas; Maragoudakis , Manolis
Part 3: Second International Workshop on Computational Intelligence in Software Engineering (CISE 2012); International audience; In this work, we propose and evaluate a Higher Order Singular Value Decomposition (HOSVD) of a tensor as a means to classify player behavior and adjust game difficulty dynamically. Applying this method to player data collected during a plethora of game sessions resulted in a reduction of the dimensionality of the classification problem and a robust classification of...
Laudner, Kevin G
Injuries stemming from shoulder instability are very common among athletes participating in contact sports, such as football. Previous research has shown that increased laxity negatively affects the function of the sensorimotor system potentially leading to a pathological cycle of shoulder dysfunction. Currently, there are no data detailing such effects among football players. Therefore, the purpose of this study was to examine the differences in upper extremity sensorimotor control among football players compared with that of a control group. Forty-five collegiate football players and 70 male control subjects with no previous experience in contact sports participated. All the subjects had no recent history of upper extremity injury. Each subject performed three 30-second upper extremity balance trials on each arm. The balance trials were conducted in a single-arm push-up position with the test arm in the center of a force platform and the subjects' feet on a labile device. The trials were averaged, and the differences in radial area deviation between groups were analyzed using separate 1-way analyses of variance (p football players showed significantly more radial area deviation of the dominant (0.41 ± 1.23 cm2, p = 0.02) and nondominant arms (0.47 ± 1.63 cm2, p = 0.03) when compared with the control group. These results suggest that football players may have decreased sensorimotor control of the upper extremity compared with individuals with no contact sport experience. The decreased upper extremity sensorimotor control among the football players may be because of the frequent impacts accumulated during football participation. Football players may benefit from exercises that target the sensorimotor system. These findings may also be beneficial in the evaluation and treatment of various upper extremity injuries among football players.
Boone, Jan; Bourgois, Jan
PURPOSE: The present study aimed to gain insight into the physiological profile of elite basketball players in Belgium in relation to their position on the field. METHODS: The group consisted of 144 players, divided into 5 groups according to position (point guards [PG], shooting guards [SG], small forwards [SF], power forwards [PF] and centers [C]). The anthropometrics were measured and the subjects underwent fitness tests (incremental running test, 10m-sprint,5x10m,Squat and Counter Move...
Puspaningtyas, Desty Ervira; Afriani, Yuni; Mahfida, Silvi Lailatul; Kushartanti, Wara; Farmawati, Arta
Training is conducted to improve physiological functions that can support improvementof cardio-respiratory function (O2max). However, intensive training can lead to oxidativestress, which can contribute to health problems. The purpose of this study was to evaluatethe effect of training on serum lipid peroxidation levels in student soccer players. Thestudy was pre-experimental study with a one-shot case design conducted in April 2014.Twelve student soccer players from UGM who chosen by purposi...
Greditzer, Harry G.; Hutchinson, Ian D.; Geannette, Christian S.; Hotchkiss, Robert N.; Kelly, Bryan T.; Potter, Hollis G.
Background: Os styloideum describes an accessory carpal ossicle between the trapezoid, the capitate, and the second and third metacarpals. Injuries to this tissue have been described as part of the carpal boss syndrome. While the etiology of os styloideum remains uncertain, it may represent a physiologic response to altered loading forces in the wrist, similar to the development of cam-type deformity in the hips of ice hockey players or the Bennett lesion in the shoulders of baseball pitchers. Hypothesis: Professional hockey players will have a higher prevalence of os styloideum compared with the general population. Study Design: Case series. Level of Evidence: Level 4. Methods: A retrospective review of 16 professional hockey players from 4 different National Hockey League (NHL) teams who underwent unilateral imaging of the wrist was performed. Seventeen wrists were reviewed for the presence of os styloideum. Results: Thirteen of 16 players (81%) had an os styloideum, representing an increased prevalence compared with the general population. Previous clinical and cadaveric studies estimated a general prevalence of up to 19% (P < 0.001). For the 10 players who had their leading wrist scanned, 9 had an os styloideum (90%). Ten of 11 (91%) players demonstrated a bone marrow edema pattern within the metacarpal and the os styloideum on magnetic resonance imaging. There was no significant association between the presence of an os styloideum and the player’s position, leading wrist, or years in the league. Conclusion: There appears to be an increased prevalence of os styloideum among NHL players, and team physicians should consider this finding while formulating a differential diagnosis for dorsal wrist pain. Clinical Relevance: This study identified NHL players as having an increased prevalence of os styloideum compared with the general population. By doing so, these findings represent an opportunity to enhance our understanding of the etiology, clinical significance
Martin, Louise; Lambeth, Anneliese; Scott, Dawn
The aim of the study was to establish the nutritional practices and activity patterns of elite female soccer players. The nutritional intake of 16 female England Soccer players was self-reported over a seven-day period. Participants were provided with written and verbal guidelines for the completion of the diaries. Training details were also recorded, and used in combination with BMR predictions to calculate daily energy expenditure. Energy, macronutrient and micronutrient intakes were determined using DietMaster 4.0 software. Results suggest that energy intake was low (1904 ± 366.3 kcal) in relation to previous recommendations for soccer players. Energy expenditure (2153.5 ± 596.2 kcal) was not significantly different (p > 0.05) from intake, suggesting energy balance was achieved. Carbohydrate (53.8 ± 6.8%), protein (16.8 ± 2.1%) and fat (28.8 ± 6.6%) intakes were in line with recommendations. Fluid intake (2466 ± 1350.5ml·day(-1)) was sufficient to meet baseline recommendations, but would need to be higher to meet the additional requirement of training and competition. With the exception of vitamin A and iron, all micronutrient intakes were higher than the DRI. In conclusion, recommendations for female soccer players are to encourage consumption of carbohydrate-electrolyte beverages to enhance carbohydrate intake and increase fluid intake, and ensure sufficient iron rich foods are included in the diet to meet the DRI. Key pointsFemale soccer players demonstrate a low energy intake in relation to predicted requirements, but were in energy balance in this study.Increased carbohydrate intake may be beneficial to both training and competition performance of elite female soccer playersFluid requirements should be addressed on an individual basis and matched to player requirements.The iron status of female soccer players may be compromised due to insufficient dietary intake to meet the DRV.
Martin, Louise; Lambeth, Anneliese; Scott, Dawn
The aim of the study was to establish the nutritional practices and activity patterns of elite female soccer players. The nutritional intake of 16 female England Soccer players was self-reported over a seven-day period. Participants were provided with written and verbal guidelines for the completion of the diaries. Training details were also recorded, and used in combination with BMR predictions to calculate daily energy expenditure. Energy, macronutrient and micronutrient intakes were determined using DietMaster 4.0 software. Results suggest that energy intake was low (1904 ± 366.3 kcal) in relation to previous recommendations for soccer players. Energy expenditure (2153.5 ± 596.2 kcal) was not significantly different (p > 0.05) from intake, suggesting energy balance was achieved. Carbohydrate (53.8 ± 6.8%), protein (16.8 ± 2.1%) and fat (28.8 ± 6.6%) intakes were in line with recommendations. Fluid intake (2466 ± 1350.5ml·day-1) was sufficient to meet baseline recommendations, but would need to be higher to meet the additional requirement of training and competition. With the exception of vitamin A and iron, all micronutrient intakes were higher than the DRI. In conclusion, recommendations for female soccer players are to encourage consumption of carbohydrate-electrolyte beverages to enhance carbohydrate intake and increase fluid intake, and ensure sufficient iron rich foods are included in the diet to meet the DRI. Key points Female soccer players demonstrate a low energy intake in relation to predicted requirements, but were in energy balance in this study. Increased carbohydrate intake may be beneficial to both training and competition performance of elite female soccer players Fluid requirements should be addressed on an individual basis and matched to player requirements. The iron status of female soccer players may be compromised due to insufficient dietary intake to meet the DRV. PMID:24198690
Donohue, Sarah E.; Woldorff, Marty G.; Mitroff, Stephen R.
Recent research has demonstrated enhanced visual attention and visual perception in individuals with extensive experience playing action video games. These benefits manifest in several realms, but much remains unknown about the ways in which video game experience alters perception and cognition. The current study examined whether video game players’ benefits generalize beyond vision to multisensory processing by presenting video game players and non-video game players auditory and visual stim...
The purpose of this study is to investigate the self-esteem levels of futsal players according to certain variables. The samples of the study constituted 119 females and 96 males; a total of 215 players with an average age of 21.57 ± 2.20 years. The research was carried out with the end of "Rosenberg self-esteem Scale" developed by…
One result of opening up the European gas market to competition has been to increase the number and diversity of the players involved, whether producers, suppliers or electric utilities. However, while the gas on offer is still controlled by a handful of market players given the increasing importance of state-owned companies from exporting countries outside Europe, the downstream gas sector continues to show a strong concentration of incumbent operators seeking a dominant position in the supply of gas. (author)
Ooi, Cheong Hwa; Tan, Albert; Ahmad, Azwari; Kwong, Kien Weng; Sompong, Ruji; Ghazali, Khairul Aswadi Mohd; Liew, Swee Lee; Chai, Wen Jin; Thompson, Martin William
The aims of this study were to establish the physical and physiological attributes of elite and sub-elite Malaysian male badminton players and to determine whether these attributes discriminate elite players from sub-elite players. Measurements and tests of basic anthropometry, explosive power, anaerobic recovery capacity, badminton-specific movement agility, maximum strength, and aerobic capacity were conducted on two occasions, separated by at least one day. The elite (n = 12) and sub-elite (n = 12) players' characteristics were, respectively: mean age 24.6 years (s = 3.7) and 20.5 years (s = 0.7); mass 73.2 kg (s = 7.6) and 62.7 kg (s = 4.2); stature 1.76 m (s = 0.07) and 1.71 m (s = 0.05); body fat 12.5% (s = 4.8) and 9.5% (s = 3.4); estimated VO(2max) 56.9 ml . kg(-1) . min(-1) (s = 3.7) and 59.5 ml . kg(-1) . min(-1) (s = 5.2). The elite players had greater maximum absolute strength in one-repetition maximum bench press (P = 0.015) compared with the sub-elite players. There were significant differences in instantaneous lower body power estimated from vertical jump height between the elite and sub-elite groups (P badminton-specific movement agility tests. Our results show that elite Malaysian male badminton players are taller, heavier, and stronger than their sub-elite counterparts. The test battery, however, did not allow us to discriminate between the elite and sub-elite players, suggesting that at the elite level tactical knowledge, technical skills, and psychological readiness could be of greater importance.
Digital Educational Games, as one of the most important application areas of Serious Games, combine positive properties of digital games, such as strong motivation for players and inherent learning processes, with educational methods and technologies. Adaptive algorithms allow such games to be aligned automatically to the needs of different players, thereby increasing the learning efficacy. However, educational games are among the most complex game production endeavors, since they are often f...
Yuraima Margelis Matos De Rojas
Full Text Available To strengthen cognitive development in students requires the use of innovative, creative and formative strategies that allow it to achieve, being one of the didactic strategies chess. For what was proposed as research purpose: Identify the intelligences developed by the student athlete of the Sports Talent Education Unit that play chess, to suggest some recommendations that can be put into practice in educational institutions. Methodologically it was approached from the qualitative paradigm through a phenomenological method that reveals the reality from the experiences and experiences of the social actors. Six key students of the institution were chess players, to whom an open interview was applied to obtain the necessary information, which was systematized to extract the categories, codifications and triangulate the information. As results, it was obtained that the students develop the intelligences: logical-mathematical, linguistic, spatial and visual, as the intrapersonal during the game of chess and in the learning processes. Configured in categories, analyzed and interpreted from the voices of social actors, theorists and researchers. Suggesting some recommendations that can be put into practice to strengthen the intelligences in the student.
Full Text Available Testing and measurement in basketball is basically supposed to help in the initial evaluation and interpretation of features and capabilities of players that are important for their activity. The main objective of testing is the possibility of obtaining information about the three general indicators in basketball practice, namely: the level of current results in certain ability, the pace of results improvement in the ability and stability of the results in tests of ability. For this purpose, testing and measurement of young basketball players, members of the Montenegro under-18 team, was carried out. The aim of this paper is to present the basic features and capabilities of young basketball players of Montenegro and their comparison with some other teams. Variables from anthropometry space were measured: body height, arm span, reach height, body mass. Motor skills were observed by variables: the last squat, thrust from a flat bench, rear thrust, lying-sitting for 30 seconds, sargent test, long jump, 20 yard test, kamikaze, špagat, sitting bow. Based on the processed results it can be concluded that the motor skills of our young players, tested in this study, are at the level of the young players of other representations. The results will be of great help to coaches who work with these players.
Rafnsson, Elis Thor; Valdimarsson, Örnólfur; Sveinsson, Thorarinn; Árnason, Árni
To examine the incidence, type, location, and severity of injuries in Icelandic elite male handball players and compare across factors like physical characteristics and playing position. Prospective cohort study. The latter part of the preseason and the competitive season of Icelandic male handball. Eleven handball teams (185 players) from the 2 highest divisions in Iceland participated in the study. Six teams (109 players) completed the study. Injuries were recorded by the players under supervision from their team physiotherapists or coaches. Coaches recorded training exposure, and match exposure was obtained from the Icelandic and European Handball Federations. The players directly recorded potential risk factors, such as age, height, weight, previous injuries, and player position. Injury incidence and injury location and number of injury days. Recorded time-loss injuries were 86, of which 53 (62%) were acute and 33 (38%) were due to overuse. The incidence of acute injuries was 15.0 injuries/1000 hours during games and 1.1 injuries/1000 hours during training sessions. No significant difference was found in injury incidence between teams, but number of injury days did differ between teams (P = 0.0006). Acute injuries were most common in knees (26%), ankles (19%), and feet/toes (17%), but overuse injuries occurred in low back/pelvic region (39%), shoulders (21%), and knees (21%). Previous knee injuries were the only potential risk factor found for knee injury. The results indicate a higher rate of overuse injuries in low back/pelvic region and shoulders than in comparable studies.
Zeelie, S C; Bornman, J E; Botes, A C
This article reports on role player expectations regarding the education of nursing research. The importance of the role player expectations are two-fold: firstly as a factor in the external environment influencing and guiding the formulation phase of the development of standards and secondly, due to the clear indications of problems regarding nursing research in the nursing profession in literature. The role player expectations were elicited using a qualitative, exploratory and contextual design. The role player population included nurse educators, nurses in managerial, clinical and research positions, students and the medical profession. The data was gathered using the naïve sketches and qualitative data analysis was done using Morse & Field's approach (1996:103-107) in combination with Tesch's data analysis approach as cited by Creswell (1994:154-156). Sixty initial categories were narrowed down to six final categories, which are the research learning programme, personnel, students, departmental policies, funding and support systems. The role player expectations were elicited as part of a research study aiming tot develop a self-evaluation system for quality assurance in nursing research and as such, the role player expectations plays a pivotal role in the development of standards for the self-evaluation system.
Gardner, Raquel C; Hess, Christopher P; Brus-Ramer, Marcel; Possin, Katherine L; Cohn-Sheehy, Brendan I; Kramer, Joel H; Berger, Mitchel S; Yaffe, Kristine; Miller, Bruce; Rabinovici, Gil D
Previous studies report that cavum septum pellucidum (CSP) is frequent among athletes with a history of repeated traumatic brain injury (TBI), such as boxers. Few studies of CSP in athletes, however, have assessed detailed features of the septum pellucidum in a case-control fashion. This is important because prevalence of CSP in the general population varies widely (2% to 85%) between studies. Further, rates of CSP among American pro-football players have not been described previously. We sought to characterize MRI features of the septum pellucidum in a series of retired pro-football players with a history of repeated concussive/subconcussive head traumas compared with controls. We retrospectively assessed retired American pro-football players presenting to our memory clinic with cognitive/behavioral symptoms in whom structural MRI was available with slice thickness ≤2 mm (n=17). Each player was matched to a memory clinic control patient with no history of TBI. Scans were interpreted by raters blinded to clinical information and TBI/football history, who measured CSP grade (0-absent, 1-equivocal, 2-mild, 3-moderate, 4-severe) and length according to a standard protocol. Sixteen of 17 (94%) players had a CSP graded ≥2 compared with 3 of 17 (18%) controls. CSP was significantly higher grade (pfootball players compared with patients without a history of TBI.
Haxhiu, Bekim; Murtezani, Ardiana; Zahiti, Bedri; Shalaj, Ismet; Sllamniku, Sabit
The aim of this study was to identify risk factors related to the occurrence of injuries in football players. The study included 216 football players from 12 teams in the elite football league. Football-related injury data were collected prospectively during the 2012/2013 competitive season. At baseline the following information was collected for the players: anthropometric measurements (weight, height, BMI, subcutaneous skinfolds), playing experience, injury history, physical fitness performance test (agility run), peak oxygen uptake. The incidence, type and severity of injuries and training and game exposure times were prospectively documented for each player. Most of the players (n = 155, 71.7%) sustained the injures during the study period. The overall injury incidence during the regular season was 6.3 injuries per 1000 athlete-exposures (95% confidence interval, 4.31-9.67). Multivariate logistic regression analysis showed that playing experience (odds ratio [OR] = 0.44; 95% CI = 0.32-0.61, p football for more than 1 month, with knee injuries (25.42%) being the most severe type. The risk factors that increase injury rates in football players were previous injury, higher age and years of playing. Future research should include adequate rehabilitation program to reduce the risk of injuries.
Proietti, Riccardo; di Fronso, Selenia; Pereira, Lucas A; Bortoli, Laura; Robazza, Claudio; Nakamura, Fabio Y; Bertollo, Maurizio
Heart rate variability (HRV) has been increasingly used to monitor team sports athletes. Besides the traditional time domain indices (i.e., the SD of successive RR intervals [SDNN] and the root mean square difference of successive normal RR intervals [RMSSD]), recently the use of the stress score (SS), which is an inverse function of the SD2 index derived from the Poincaré plot, and the sympathetic/parasympathetic ratio (S/PS) to monitor soccer players has been proposed. However, the reliability of these new indices and the ability of HRV to differentiate between soccer competitive levels are unknown. The aim of this study was to analyze the reliability of the different HRV-derived indices in professional soccer players during the competitive period and to compare HRV of professional soccer players from 3 teams of distinct competitive levels (i.e., Italian Second Division [2D], European League [EL], and Champions League [CL]). Fifty-four male professional soccer players from 3 different teams of 2 European countries (Italy and Germany) participated in the study. The intraclass correlation coefficient values of the HRV indices varied from 0.78 (very large) to 0.90 (near perfect). The coefficient of variation (CV) values for RMSSD and SDNN were all soccer players and is able to differentiate between international- and national-level players.
Figueiredo, Ricardo Rodrigues; Azevedo, Andreia Aparecida de; Oliveira, Patrícia Mello de; Amorim, Sandro Pereira Vasconcellos; Rios, Artur Guedes; Baptista, Vanderlei
Exposure to loud noise is one of the main causes of tinnitus. To analyze the incidence of tinnitus in mp3 player users and non-users. One hundred subjects aged from 15 to 30 years were enrolled, 54 of them were regular mp3 player users and 46 were not. Patients with continuous tinnitus for at least 6 months completed the Tinnitus Handicap Inventory (THI) and were tested with high frequency audiometry and transient-evoked otoacoustic emissions (TAOE). A cross-sectional cohort study. The incidence of tinnitus in non-users was about 8 %; in mp3 player users it was about 28 %, a statistically significant difference. Hearing thresholds at 8 kHz were significantly higher in tinnitus patients that used mp3 portable players.TAOE were reduced at 2 kHz in the users group. No statistically significant difference was found in the THI scores between the two groups. Tinnitus was more frequent in teenagers and young adults who regularly listen to mp3 music in players. Moreover, the incidence of tinnitus among mp3 player users was associated with higher hearing thresholds at 8 kHz and lower TOAE at 2 kHz.
Kim, Young Bin; Kang, Shin Jin; Lee, Sang Hyeok; Jung, Jang Young; Kam, Hyeong Ryeol; Lee, Jung; Kim, Young Sun; Lee, Joonsoo; Kim, Chang Hun
In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players' characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse) was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.
Byrd, J W Thomas; Jones, Kay S
To report the results of hip arthroscopy among high-level baseball players as recorded by outcome scores and return to baseball. All patients undergoing hip arthroscopy were prospectively assessed with the modified Harris Hip Score. On review of all procedures performed over a 12-year period, 44 hips were identified among 41 intercollegiate or professional baseball players who had achieved 2-year follow-up. Among the 41 players, follow-up averaged 45 months (range, 24 to 120 months), with a mean age of 23 years (range, 18 to 34 years). There were 23 collegiate (1 bilateral) and 18 professional (2 bilateral) baseball players, including 10 Major League Baseball players. Of the 8 Major League Baseball pitchers, 6 (75%) also underwent ulnar collateral ligament elbow surgery. Improvement in the modified Harris Hip Score averaged 13 points (from 81 points preoperatively to 94 points postoperatively); a paired-samples t test determined that this mean improvement of 13 points was statistically significant (P arthroscopy. This study supports the idea that arthroscopic treatment for a variety of hip pathologies in high-level baseball players provides a successful return to sport and improvement in functional outcome scores. Level IV, therapeutic case series. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
The aim of the research was an analysis of the eating habits of professional volleyball players according to their sex and age. The research has been carried out on a group of 210 men players and women players at the age of 13-25, representatives of sports clubs in Ostrołeka, Myślenice, Bydgoszcz and Warszawa. The research has revealed a limited realisation of rational diets by both men and women players. The most common mistakes made by them include a smaller number of meals during the day than recommended (especially among men), taking up training on empty stomach and insufficient frequency of consumption of dairy products, fish, vegetables and fruit. The research has also revealed excessive consumption of sweets, sweet sparkling drinks and fast food (mainly among men). The examined players to some extent only apply regular strategies of rehydration of their organisms. A high percentage of them do not pay attention to supplementation of liquids after an effort or they drink a lot of liquids at one time. The most frequently chosen drinks were mineral water and isotonic drinks. Supplementation was applied by a small percentage of the players, mainly men, who most often chose vitamins, Izostar, creatine, L-carnitine and HMB.
Harris, Joshua D.; Walton, David M.; Erickson, Brandon J.; Verma, Nikhil N.; Abrams, Geoffrey D.; Bush-Joseph, Charles A.; Bach, Bernard R.; Cole, Brian J.
Background: Use of microfracture in the knees of National Basketball Association (NBA) players is controversial. Hypotheses: (1) There would be a high rate of return to sport (RTS) in NBA players following microfracture, (2) players would RTS the season following surgery, (3) preoperative player performance would not be significantly different on RTS, and (4) there would be no significant difference in RTS rate or postoperative performance in players undergoing microfracture in comparison wit...
Sultana, Kazi Afroza
Background: Strategic alliances enable businesses to gain competitive advantage by providing access to the each other s resources which can be utilized to ensure the business profitability of the firms in the alliance. Telecommunication industry is dominated by large players, such as Mobile Network Operators. In contrary, comparatively small players, such as Mobile Virtual Network Operators, are struggling to sustain themselves in the business. Although a lot of literature is present on strat...
Diaz, Ruth L; Wong, Ulric; Hodgins, David C; Chiu, Carina G; Goghari, Vina M
Violent video game playing has been associated with both positive and negative effects on cognition. We examined whether playing two or more hours of violent video games a day, compared to not playing video games, was associated with a different pattern of recognition of five facial emotions, while controlling for general perceptual and cognitive differences that might also occur. Undergraduate students were categorized as violent video game players (n = 83) or non-gamers (n = 69) and completed a facial recognition task, consisting of an emotion recognition condition and a control condition of gender recognition. Additionally, participants completed questionnaires assessing their video game and media consumption, aggression, and mood. Violent video game players recognized fearful faces both more accurately and quickly and disgusted faces less accurately than non-gamers. Desensitization to violence, constant exposure to fear and anxiety during game playing, and the habituation to unpleasant stimuli, are possible mechanisms that could explain these results. Future research should evaluate the effects of violent video game playing on emotion processing and social cognition more broadly. © 2015 Wiley Periodicals, Inc.
Full Text Available Grounded in the theoretical framework of achievement goal theory and perfectionism theory, the purpose of this study was to examine how self-assessed perceived abilities covariance these variables among Norwegian football academy players. 140 adolescent football players participated, representing three football academies. Perceived competence was reported as equivalent to or better than others. Perfectionism scores showed personal standards as the highest of the dimensions of perfectionism, while perceived parental pressure was lowest. In contrast, mean task orientation and perceived mastery climate were higher than ego orientation and perceived performance climate. The correlation analysis showed that perceived competence correlated positively with personal standards. Personal standards correlated positively with the rest of the perfectionism dimensions as well as ego orientation, perceived mastery- and performance climate. Concern over mistakes was positively correlated with ego-orientation. Overall, findings suggested that personal standards correlate with perceived competence, while these variables also relate to other perfectionism dimensions, goal orientations and perceived motivational climate. Therefore, coaches should highlight the importance of high personal standards, as a potentially maladaptive function on talent development.
Lazar, Damien J.; Lichtenstein, Jonathan D.; Tybor, David J.
Background: Ultimate Frisbee (ultimate) is a fast-growing, popular sport played nationally by over 4 million athletes. While several studies have examined injury rates in ultimate, no work has investigated the prevalence of concussions specifically or players’ knowledge and management of those injuries. Purpose: To estimate the lifetime prevalence of concussions in ultimate and to assess players’ knowledge of concussions as well as their concussion management behaviors. Study Design: Descriptive epidemiology study. Methods: From June to November 2015, we collected ultimate-related concussion data via an anonymous web-based survey, the Concussion in Ultimate Frisbee Survey, from a convenience sample of 787 male and female ultimate players across the United States. Results: There were 553 male and 234 female respondents included in the analysis; 26.58% of men and 24.79% of women reported that they had sustained at least 1 concussion while playing ultimate, with 45.58% and 43.10% of those men and women, respectively, reporting multiple concussions. A total of 67.81% of men and 78.21% of women stated that they would remove themselves from play after sustaining a given concussion, although 45.99% of men and 37.62% of women indicated that they had returned to play in the same game or practice. Conclusion: Our preliminary data suggest that concussions do commonly occur in competitive ultimate and that better education and management of concussions in ultimate athletes are needed. This study is an important first step in deepening our understanding of these issues. PMID:29552572
Full Text Available There is an ongoing concern about the risk of injury to the spine in professional rugby players. The objective of this study was to investigate the prevalence of vertebral fracture using vertebral fracture assessment (VFA dual energy X-ray absorptiometry (DXA imaging in professional male rugby players. Ninety five professional rugby league (n = 52 and union (n = 43 players (n = 95; age 25.9 (SD 4.3 years; BMI: 29.5 (SD 2.9 kg.m2 participated in the research. Each participant received one VFA, and one total body and lumbar spine DXA scan (GE Lunar iDXA. One hundred and twenty vertebral fractures were identified in over half of the sample by VFA. Seventy four were graded mild (grade 1, 40 moderate (grade 2 and 6 severe (grade 3. Multiple vertebral fractures (≥2 were found in 37 players (39%. There were no differences in prevalence between codes, or between forwards and backs (both 1.2 v 1.4; p>0.05. The most common sites of fracture were T8 (n = 23, T9 (n = 18 and T10 (n = 21. The mean (SD lumbar spine bone mineral density Z-score was 2.7 (1.3 indicating high player bone mass in comparison with age- and sex-matched norms. We observed a high number of vertebral fractures using DXA VFA in professional rugby players of both codes. The incidence, aetiology and consequences of vertebral fractures in professional rugby players are unclear, and warrant timely, prospective investigation.
te Wierike, Sanne C M; de Jong, Mark C; Tromp, Eveline J Y; Vuijk, Pieter J; Lemmink, Koen A P M; Malina, Robert M; Elferink-Gemser, Marije T; Visscher, Chris
Factors affecting repeated sprint ability (RSA) were evaluated in a mixed-longitudinal sample of 48 elite basketball players 14-19 years of age (16.1 ± 1.7 years). Players were observed on 6 occasions during the 2008-09 and 2009-10 seasons. Three following basketball-specific field tests were administered on each occasion: the shuttle sprint test for RSA, the vertical jump for lower body explosive strength (power), and the interval shuttle run test for interval endurance capacity. Height and weight were measured; body composition was estimated (percent fat, lean body mass). Multilevel modeling of RSA development curve was used with 32 players (16.0 ± 1.7 years) who had 2 or more observations. The 16 players (16.1 ± 1.8 years) measured on only 1 occasion were used as a control group to evaluate the appropriateness of the model. Age, lower body explosive strength, and interval endurance capacity significantly contributed to RSA (p ≤ 0.05). Repeated sprint ability improved with age from 14 to 17 years (p ≤ 0.05) and reached a plateau at 17-19 years. Predicted RSA did not significantly differ from measured RSA in the control group (p ≥ 0.05). The results suggest a potentially important role for the training of lower body explosive strength and interval endurance capacity in the development of RSA among youth basketball players. Age-specific reference values for RSA of youth players may assist basketball coaches in setting appropriate goals for individual players.
Full Text Available The purpose of this study was two-fold, firstly, to evaluate the anthropometric profile of Indian interuniversity basketball players and, secondly, to search the correlation of body mass index, % body fat, hand grip strength (right dominant and Vo2max,with other anthropometric characteristics studied. Eleven anthropometriccharacteristics, four body composition parameters, two physical and two physiological variables were measured on randomly selected 60 inter-university Indian basketball players (35 males and 25 females aged 18–25 years from Guru Nanak Dev University, Amritsar, Punjab, India with adequate controls (n = 102, 52 males and 50 females. The results indicated that male basketball players were taller (6.63% and heavier (7.31% and female basketball players were slightly taller (0.31% and lighter (3.74% than their control counterparts. One way analysis of variance showed significant (p ≤ .004 - .000 between group differences in all the variables (excepthip circumference between basketball players and controls. In basketball players, significantly positive correlations were found with BMI and other 12 variables, with percent body fat and 7 variables, with right hand grip strength and 12 variables and with Vo2max and other 9 variables, and significantly negative correlationswere found with BMI and other 1 variable (% lean body mass, with percent body fat and other 6 variables, with right hand grip strength and other 2 variables and with Vo2max with other 3 variables. The findings of the present study might be useful in future investigation on player selection, talent identification in the game of basketball and its training program development.
White, Peta E; Donaldson, Alex; Sullivan, S John; Newton, Joshua
Background Preventing concussion in sport is a global challenge. To assess community-level adult male Australian Football players’ views on following the Australian Football League's (AFL) concussion guidelines. Methods 3 focus groups, each comprising 6 players from 1 regional league, were conducted until saturation of issues raised. Discussions followed a semistructured script and were audio-recorded and transcribed verbatim. Thematic analysis was conducted by 2 coders independently. Results Identified advantages of the guidelines included highlighting the seriousness of concussion; changing the culture around playing with concussion and shifting return-to-play decision responsibility from players to others. Disadvantages included players being removed from play unnecessarily; removal of players’ rights to decide if they are fit to play and players changing their behaviours to avoid being removed from play. Identified facilitators to guideline use included local league enforcement; broad information dissemination and impartial medically trained staff to assess concussion. Identified barriers to guideline use included players’ desire to play at all costs; external pressure that encouraged players to return to play prematurely; and inconvenience and cost. Conclusions Players generally understand that the AFL concussion guidelines protect their long-term welfare. However, their desire to play at all costs and help their team win is a common barrier to reporting concussion and adhering to guidelines. Leagues should take a lead role by mandating and enforcing the use of the guidelines and educating coaches, game day medical providers and players. The return-to-play component of the guidelines is complex and needs further consideration in the context of community sport. PMID:28890801
Ozunlu, Nihan; Tekeli, Hatice; Baltaci, Gul
Context: The stability of the scapula in relation to the entire moving upper extremity is the key in the throwing sequence. The importance of scapular positioning in volleyball players has been well documented in the literature, but no one has compared scapular positioning between volleyball players and sedentary people. Objective: To compare measurements of scapular mobility obtained using the lateral scapular slide test between volleyball players and sedentary participants without shoulder impairments and to compare changes in scapular mobility in players according to the number of years of sport participation. Design: Cross-sectional study. Setting: University research laboratory. Patients or Other Participants: A total of 121 people at a single university volunteered. Of these, 67 were sedentary (age = 24.3 ± 2.34 years, height = 1.69 ± 0.09 m, mass = 65.1 ± 11.91 kg); 54 were volleyball players from 4 professional teams and were separated into 2 groups according to their years of sport participation. The first group was named young players (n = 31; age = 17.7 ± 2.58 years, height = 1.83 ± 0.10 m, mass = 68.3 ± 12.21 kg, sport participation ≤ 9 years), and the second group was named old players (n = 23; age = 26.9 ± 3.39 years, height = 1.95 ± 4.38 m, mass = 90.7 ± 5.75 kg, sport participation ≥ 10 years). Main Outcome Measure(s): Study participants completed a rating scale for pain and a questionnaire about demographic and shoulder problems. One assessor performed the lateral scapular slide test and additional flexibility measurements around the shoulder girdle. Flexibility (external rotation, internal rotation) and scapular position (1, 2, 3) were compared among groups (young players, old players, sedentary people) and between sides (dominant, nondominant). Results: In sedentary participants, we found differences for position 1 (t66 = 3.327, P = .002), position 2 (t66 = 2.491, P = .004), position 3 (t66 = 2.512, P = .006), and internal rotation
Anakwenze, Okechukwu A; Namdari, Surena; Auerbach, Joshua D; Baldwin, Keith; Weidner, Zachary D; Lonner, Baron S; Huffman, G R; Sennett, Brian J
Retrospective case-control study. To quantify the athletic performance profiles after lumbar discectomy (LD) in a cohort of National Basketball Association (NBA) players in comparison with a control group of matched NBA players who did not undergo LD during the same study period. LD provides symptomatic relief and improved functional outcomes in the majority of patients as assessed by validated measures such as Oswestry Disability Index, Visual Analog Scale, and Short Form-36 (SF-36). Among professional athletes, however, the goal of lumbar HNP treated by discectomy is not only to improve functional status but also, ultimately, to return the player to preinjury athletic performance levels. No study to date has compared the athletic performance profiles before and after discectomy in professional athletes. An analysis of NBA games summaries, weekly injury reports, player profiles, and press releases was performed to identify 24 NBA players who underwent LD for symptomatic lumbar HNP between 1991 and 2007. A 1:2 case: control study was performed using players without history of lumbar HNP who were matched for age, position, experience, and body mass index as control subjects (n = 48). Paired t tests were conducted on the following parameters: games played, minutes per game, points per 40 minutes, rebounds per 40 minutes, assists per 40 minutes, steals per 40 minutes, blocks per 40 minutes, and shooting percentage. For each athletic performance outcome, between-group comparisons evaluating preindex to postindex season performance were done (index season = season of surgery). In the LD group, 18 of 24 players (75%) returned to play again in the NBA, compared with 42 of 48 players (88%, P = 0.31) in the control group. One year after surgery, between-group comparisons revealed statistically significant increase in blocked shots per 40 minutes in the LD (0.18) versus control group (-0.33; P = 0.008) and a smaller decrease in rebounds per 40 minutes in the LD (-0
Lehman, Everett J
The purpose of this article is to review the history of head injuries in relation to American-style football play, summarize recent research that has linked football head injuries to neurodegeneration, and provide a discussion of the next steps for refining the examination of neurodegeneration in football players. For most of the history of football, the focus of media reports and scientific studies on football-related head injuries was on the acute or short-term effects of serious, traumatic head injuries. Beginning about 10 years ago, a growing concern developed among neurologists and researchers about the long-term effects that playing professional football has on the neurologic health of the players. Autopsy-based studies identified a pathologically distinct neurodegenerative disorder, chronic traumatic encephalopathy, among athletes who were known to have experienced concussive and subconcussive blows to the head during their playing careers. Football players have been well represented in these autopsy findings. A mortality study of a large cohort of retired professional football players found a significantly increased risk of death from neurodegeneration. Further analysis found that non-line players were at higher risk than line players, possibly because of an increased risk of concussion. Although the results of the studies reviewed do not establish a cause effect relationship between football-related head injury and neurodegenerative disorders, a growing body of research supports the hypothesis that professional football players are at an increased risk of neurodegeneration. Significant progress has been made in the last few years on detecting and defining the pathology of neurodegenerative diseases. However, less progress has been made on other factors related to the progression of those diseases in football players. This review identifies three areas for further research: (a) quantification of exposure - a consensus is needed on the use of clinically
Malmgren, A; Dencker, M; Stagmo, M; Gudmundsson, P
Long-term intensive endurance training leads to increased left ventricular mass and increased left ventricular end-diastolic and left atrial end-systolic diameters. Different types of sports tend to give rise to distinct morphological forms of the athlete's heart. However, the sport-specific aspects have not been fully investigated in female athletes. The purpose of the present study was to investigate differences in left and right cardiac dimensions, cardiac volumes, and systolic and diastolic function in elite female handball players compared to sedentary controls. A cross-sectional study of 33 elite female handball players was compared to 33 matched sedentary controls. Mean age was 21.5±2 years. The subjects underwent echocardiography examinations, both 2-dimensional (2DE) and 3-dimensional (3DE). Cardiac dimensions and volumes were quantified using M-mode, 2DE and 3DE. Systolic and diastolic left ventricular functions were also evaluated. All cardiac dimensions and volumes were adjusted for body surface area (BSA). Left atrium and left ventricle volumes were significantly (Phandball players compared with sedentary controls. Even right atrium area as well as right ventricular end-diastolic and end-systolic area were significantly (Phandball players. Significant differences were observed in three out of five systolic parameters. Most diastolic function parameters did not differ between the two groups. The findings from the present study suggest that similar cardiac remodeling takes place in elite female handball players as it does in athletes pursuing endurance or team game sports.
Donohue, Sarah E; Woldorff, Marty G; Mitroff, Stephen R
Recent research has demonstrated enhanced visual attention and visual perception in individuals with extensive experience playing action video games. These benefits manifest in several realms, but much remains unknown about the ways in which video game experience alters perception and cognition. In the present study, we examined whether video game players' benefits generalize beyond vision to multisensory processing by presenting auditory and visual stimuli within a short temporal window to video game players and non-video game players. Participants performed two discrimination tasks, both of which revealed benefits for video game players: In a simultaneity judgment task, video game players were better able to distinguish whether simple visual and auditory stimuli occurred at the same moment or slightly offset in time, and in a temporal-order judgment task, they revealed an enhanced ability to determine the temporal sequence of multisensory stimuli. These results suggest that people with extensive experience playing video games display benefits that extend beyond the visual modality to also impact multisensory processing.
Rubajczyk, Krystian; Świerzko, Kamil; Rokita, Andrzej
The aim of this study was to identify the relative age effect (RAE) in young Polish male (n = 3849) and female (n = 3419) basketball players aged 14 to 22 years competing in the elite games of the Polish Youth Championships. The distribution of birth dates, body height, players' match statistics, and the results of teams participating in championships were identified. The RAE was observed in male and female group, regardless of players age. Nevertheless, the greatest disproportion in the distribution of dates of birth was found in U16 group of boys (V = 0.25, p born in the first half of a calendar year. The research results show the impact of the RAE on the success of youth basketball teams in Poland. The month of birth, body height and sex may determine sporting achievements in youth basketball. Coaches should consider the chronological age and pubertal growth acceleration (APHV-age at peak height velocity) of players to optimize the process of identifying gifted basketball players, especially among boys of 14 years of age.
Zhao, Qi; Lu, Yingzhi; Jaquess, Kyle J; Zhou, Chenglin
By manipulating the congruency between body kinematics and subsequent ball trajectory, this study investigated the anticipation capabilities of regional-level, college-level, and novice table tennis players using a full video simulation occluder paradigm. Participants watched footage containing congruent, incongruent, or no ball trajectory information, to predict the landing point of the ball. They were required to choose between two potential locations to make their prediction. Percent accuracy and relevant indexes (d-prime, criterion, effect size) were calculated for each condition. Results indicated that experienced table tennis players (both regional and college players) were superior to novices in the ability to anticipate ball trajectory using kinematic information, but no difference was found between regional-level and college-level players. The findings of this study further demonstrate the superior anticipation ability of experienced table tennis players. Furthermore, the present result suggests that there may be a certain "baseline" level of motor experience in racquet sports for effective action anticipation, while the addition of further motor experience does not appear to assist direction anticipation.
Full Text Available The aims of the present study were to assess gender differences regarding lactate threshold and intermittent shuttle run performance in female and male soccer players as well as to investigate the relationships between both endurance characteristics in both genders. Fourteen female (1st division and thirteen male (4th division soccer players completed an incremental test (IT to determine running velocities at 2 and 4 mmol · l-1 blood lactate (v2 and v4 and maximum velocity (vmax as well as an interval shuttle run test (ISRT to determine running distance. Based on v2 and v4 and their percentages in relation to vmax, three intensity zones were calculated: a low lactate zone (v4. Female soccer players have a lower v4 (8.2%, vmax (11.3% and ISRT distance (31.6%. No gender difference was found in v2. In contrast to males, ISRT distance correlates with vmax as well as with v2 and v4 in female soccer players. The intensity zones v4 differ between genders. The present study revealed that gender differences increase when the running performance is intermittent including change of directions. In both genders, different relationships between lactate threshold and intermittent shuttle run performance exist. During incremental testing, the running performances of female and male players reflect different distributions of aerobic and anaerobic metabolic pathways. The revealed gender differences should be considered for soccer endurance training.
Seif Barghi, Tohid; Halabchi, Farzin; Dvorak, Jiri; Hosseinnejad, Heydar
Background: Nowadays, doping is an intricate dilemma. Football is the nationally popular sport in Iran. On the other hand, doping is a serious health hazard sport faces today. Studies dealing with athletes’ knowledge, attitudes and behavior concerning doping in football are scarce. Objectives: Therefore, we aimed to investigate the knowledge and attitudes toward doping among the football coaches and players. Patients and Methods: In a cross sectional study, 375 participants (239 football players and 136 coaches) were studied. A specially made questionnaire was applied. In this study, football teams of different provinces of the country were selected by randomized clustered sampling and questionnaires were distributed among coaches and players. Results: Knowledge of football coaches and players in three categories of doping definitions, recognition of prohibited drugs and side effects of anabolic steroids was poor or moderate in 45.3%, 88.5% and 96.5%, respectively. Conclusions: Football players and coaches have poor knowledge about doping in Iran. Moreover, they believe in some inappropriate myths without any scientific or rational basis.It seems necessary to design a comprehensive educational program for all of the athletes and coaches in Iran. PMID:26448840
Full Text Available The purpose of this study is the morphological and motor status players for both teams, and then based on the results of anthropometric and motor status of this work can also do a comparative analysis between these two sports, volleyball and basketball. Therefore, the present study is in the results (achieved of the differences and their special achievement and to skills top players. In this research, we have participation 30 players (15 for each team volleyball and basketball, the teams is from Pristina. It should be noted that all players are fully able to follow regular exercise in their clubs. Those two clubs in Pristina, have the training five days a week, the clubs are in super league and the current champion in country. We as a coach interesed about the comparisons and differences of these two sports for anthropometric and motor characteristics, and in these sports, in those two sports players have a special that is characterized by height body and explosive power. We think, that this research work serves as a continuation of the way and further research on these two sports that have a significant increase from the psycho-physical and anthropometric aspects
Vaz, Luís; Morais, Tomaz; Rocha, Henrique; James, Nic
The aim of this study was to describe the fitness profiles of senior elite Portuguese rugby players. Forty-six senior Portuguese rugby players, classified as backs (n=22; age 26.2±2.8) and forwards (n=24; age 26.7±2.9) were assessed during physical testing sessions carried out for the Portuguese National rugby team. The body composition, maximum strength and anaerobic capacity of players are hypothesized to be important physical characteristics as successful performance in rugby is predicated on the ability to undertake skilled behaviours both quickly and whilst withstanding large forces when in contact situations. No absolute differences were found between the backs and forwards for the speed performance variables although positional differences were found across all speeds when assessed relative to body mass since the forwards were significantly heavier. Coaches and the management team can use this information for monitoring progressive improvements in the physiological capacities of rugby players. These physical characteristics of elite rugby players provide normative profiles for specific positions and should form the basis of developmental programmes for adolescents. PMID:25114750
Braun, Hans; von Andrian-Werburg, Judith; Schänzer, Wilhelm; Thevis, Mario
To investigate energy intake, energy expenditure, and the nutritional status of young female elite football players using 7-day food and activity records and blood parameters. A total of 56 female elite football players [14.8 (0.7) y] completed the requested food and activity protocols. Misreporting was assessed by the ratio of energy intake to energy expenditure. The food records were analyzed concerning energy and macronutrient and micronutrient intakes, and energy expenditure was calculated using predictive equations. Hematological data and 25-hydroxyvitamin D serum concentrations were determined. Mean energy intake was 2262 (368) kcal/d [40.5 (7.0) kcal/kg/d] and estimated EE averaged 2403 (195) kcal/d. Fifty-three percent of the players exhibited an energy availability nutrition status of some young female football players. As a consequence, strategies have to be developed for a better information and application of sport nutrition practice among young female football players.
Young Bin Kim
Full Text Available In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players’ characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.
Steingard, S A
The NBA basketball players are among the finest athletes in the world. That along with the increased popularity of the NBA has put a premium on the health of the players. The course of the season puts tremendous stress and strain on players. As medical illnesses occur, the physician may feel increased pressure to put the ill player back into the line-up. One cannot let the pressure for the player to return to activity interfere with good medical practice. At times, it is difficult to allow for the natural course of an illness, however, as discussed in this article, sometimes this is exactly what needs to be done. The temptation to overtreat is also seen in some team physicians. This too must be avoided. Along with proper treatment, there is the need for education of the athletes both in social interactions and in diet and life-style. Then we, as team physicians, can sit back and enjoy the performance on the court.
Antosiak-Cyrak Katarzyna Z.
Full Text Available Purpose. The aim of the present study was assessment of laterality of the legs of young female soccer players and their non-training counterparts. Methods. The study sample comprised 9 female soccer players and 19 non-training girls. They underwent three measurement sessions, one every six months. The applied tests included kinesthetic differentiation, rate of local movements, static balance, single-leg hop, rate of global movements, strength and speed, and functional asymmetry of the legs tests. Results. The soccer players were better than the controls in their performance of the rate of local movements, rate of global movements, kinesthetic differentiation, single-leg 15m timed hop and static balance tests. Smaller differences between the results of the left and the right legs in soccer players, than in non-training girls, were noted in the rate of local movements, rate of global movements and kinesthetic differentiation tests. In the static balance test, the differences were greater in the group of soccer players. Conclusions. Lateralization of the lower limbs is a highly complex characteristic with a different variability in athletes than in nontraining individuals. The results of the present study also point to the specialization of soccer players’ left legs in body balance and single-leg hop tests.
Full Text Available The objective of this study is to assess the meaning of being that a volleyball player for the under-19 players who are experiencing a transition in their in career. Sixteen male players aged 17 and 18 were evaluated, by being asked the triggering question “What does being a volleyball player mean to you?” The analysis of the discourses was carried out according to the procedures recommended by Miles & Huberman (2004. Four response categories resulted: psychoemotional and behavioral skills, emotions in sport, recognition and financial return, skills as an athlete/player. The athletes showed that the meaning of sport lies especially in the passion for practice, but also, in the improving of their tactics and techniques, in the development of psychoemotional and behavioral skills, in the professional recognition and, to a lesser degree, in the financial aspect. Most athletes state they intend to continue in the juvenile sports categories, therefore, understanding the meaning of this activity in their life can be the key to the elaboration of a plan of psychological preparation whose aim is to provide support to their needs in this moment of professional choice.
Full Text Available The aim of this study was to describe the fitness profiles of senior elite Portuguese rugby players. Forty-six senior Portuguese rugby players, classified as backs (n=22; age 26.2±2.8 and forwards (n=24; age 26.7±2.9 were assessed during physical testing sessions carried out for the Portuguese National rugby team. The body composition, maximum strength and anaerobic capacity of players are hypothesized to be important physical characteristics as successful performance in rugby is predicated on the ability to undertake skilled behaviours both quickly and whilst withstanding large forces when in contact situations. No absolute differences were found between the backs and forwards for the speed performance variables although positional differences were found across all speeds when assessed relative to body mass since the forwards were significantly heavier. Coaches and the management team can use this information for monitoring progressive improvements in the physiological capacities of rugby players. These physical characteristics of elite rugby players provide normative profiles for specific positions and should form the basis of developmental programmes for adolescents.
Chen, Chien-Hsun; Sun, Chuen-Tsai; Hsieh, Jilung
In the latest versions of massively multiplayer online games (MMOGs), developers have purposefully made guilds part of game environments. Guilds represent a powerful method for giving players a sense of online community, but there is little quantitative data on guild dynamics. To address this topic, we took advantage of a feature found in one of today's most popular MMOGs (World of Warcraft) to collect in-game data: user interfaces that players can modify and refine. In addition to collecting data on in-game player activities, we used this feature to observe and investigate how players join and leave guilds. Data were analyzed for the purpose of identifying factors that propel game-world guild dynamics and evolution. After collecting data for 641,805 avatars on 62 Taiwanese World of Warcraft game servers between February 10 and April 10, 2006, we created five guild type categories (small, large, elite, newbie, and unstable) that have different meanings in terms of in-game group dynamics. By viewing players as the most important resource affecting guild life cycles, it is possible to analyze game worlds as ecosystems consisting of evolving guilds and to study how guild life cycles reflect game world characteristics.
Full Text Available Purpose of the present study was to examine whether influence of relative age effect (RAE exists or not in the selected 13 year old basketball players. Subjects were 20 basketball players (HT=177.35cm±6.73, BW=61.42kg±8.98, average age 13 years and 7 months ±.28, average experience in basketball training 4 years and 6 months ±1.15. Sample was divided in two groups: 11 players born in first half of the year and 9 players born in the second half of the year. One-way ANOVA was used in order to analyze the differences between the two groups of players in set of anthropometric variables (body height, arm span, standing reach height, body weight and percentage of body fat, motor variables (velocity of neuromuscular reaction time, vertical jump, 5 meters sprint, 10 meters sprint, 20 meters sprint, T-test, Zig-zag test, ball throw from sitting position, Sit-ups for 30 seconds and standing forward bend and one functional variable (20-M shuttle run test. Subjects do not differ in applied set of parameters, except in on variable (sit-ups for 30 seconds, p=.040. It was concluded that RAE does not exist in this sample of examinees.
Moreau, Axelle; Chabrol, Henri; Chauchard, Emeline
Background and aims Online Texas Hold'em poker has become a spectacular form of entertainment in our society, and the number of people who use this form of gambling is increasing. It seems that online poker activity challenges existing theoretical concepts about problem gambling behaviors. The purpose of this literature review is to provide a current overview about the population of online poker players. Methods To be selected, articles had to focus on psychopathology in a sample of online poker players, be written in English or French, and be published before November 2015. A total of 17 relevant studies were identified. Results In this population, the proportion of problematic gamblers was higher than in other forms of gambling. Several factors predicting excessive gambling were identified such as stress, internal attribution, dissociation, boredom, negative emotions, irrational beliefs, anxiety, and impulsivity. The population of online poker players is largely heterogeneous, with experimental players forming a specific group. Finally, the validity of the tools used to measure excessive or problematic gambling and irrational beliefs are not suitable for assessing online poker activity. Discussion and conclusions Future studies need to confirm previous findings in the literature of online poker games. Given that skills are important in poker playing, skill development in the frames of excessive use of online poker should be explored more in depth, particularly regarding poker experience and loss chasing. Future research should focus on skills, self-regulation, and psychopathology of online poker players.
Sato, Naoyuki; Ikeda, Kokolo; Wada, Takayuki
In many video games such as role playing games(RPGs) or sports games, computer players act not only as the opponents of the human player but also as team-mates. But computer players as team-mates often behave in a way that human players do not expect, and such mismatches cause bigger dissatisfaction than in the case of computer players as opponents. One of the reasons for such mismatches is that there are several types of sub-goals or play-styles in these games and the Ai players act without ...
Davies, Madeleine A M; Balai, Edward; Adams, Jo; Carter, John-Henry; Judge, Andrew; Newton, Julia L; Arden, Nigel K
Many funding bodies within the United Kingdom and globally have encouraged public involvement in research. The Department of Health has also called public involvement a sign of good research. Despite the wide acceptance of public involvement improving many aspects of research, from its design to its communication, involvement has varied levels of implementation across different fields of research. Sports people have rarely been involved in research, partly as this research tends not to be funded by mainstream funding bodies. This may lead to a lower research quality, not founded in player ('service user') experiences. When creating a study of former rugby player health, we were very keen to involve rugby players, understand their thoughts on player health, and their playing experiences. This article explains how rugby players were involved in several ways, but mainly in group discussions during the design stage. These groups helped to inform our study's aims and questionnaire, ensure the questionnaire would capture player experiences and answer questions relevant to players, that they would like to understand after their participation in rugby. We found that these groups were easy to arrange, and that in only one session with each group, we were given many ideas of how to improve the questionnaire and study. We believe that other studies in sports should involve sports people, and that this is a useful activity that will change data collection forms and processes, improving the research, helping researchers, and making studies more suitable for players who take part in them. Background Patient and public involvement ('involvement') in the UK has increased in accordance with funding requirements, patient-centered health policy initiatives and reporting of the positive impact of involvement for those involved, research and researchers. However, involvement has not been implemented equally across all disease areas and populations. The aim of this process was to
Wagner, Herbert; Fuchs, Patrick; Fusco, Andrea; Fuchs, Philip; Bell, W Jeffrey; Duvillard, Serge P
Biological differences between men and women are well known; however, literature-addressing knowledge about the influence of sex to specific and general performance in team handball is almost nonexistent. Consequently, the aim of the study was to assess and compare specific and general physical performance in male and female elite team handball players, to determine if the differences are consequential for general compared to specific physical performance characteristics and the relationship between general and specific physical performance. Twelve male and ten female elite team handball players performed a game based performance test, upper- und lower-body strength and power tests, a sprinting test, and an incremental treadmill-running test. Significant differences (Phandball specific tests compared to the general tests. Our findings also suggest that female players should focus more on strength training.
Full Text Available With goal to establish metric tests characteristics for estimating jumping for volleyball players, it was organized a pilot research on pattern of 23 volleyball players from cadet team and 23 students from high-school. For needs of this research four tests are valid for estimation, jump in block with left and right leg and jump in spike with left and right leg. Each test has been taken three times, so that we could with test-re test method determine their reliability, and with factor analysis their validity. Data were processed by multivariate analysis (item analysis, factor analysis from statistical package „Statistica 6.0 for windows“. On the results of research and discussion we can say that the tests had high coefficient of reliability, as well as factor validity, and these tests can be used to estimate jumping for volleyball players.
Lindgren, S; Twomey, L
Elite hockey players of both sexes from the Australian Institute of Sport were assessed for lumbar spine mobility, trunk flexion and back extensor muscle strength, hamstring flexibility and postural characteristics over a two year period. All the athletes were more mobile in rotation than the 'normal' West Australian population, and demonstrated flexible hamstrings and powerful back extensor muscles; trunk flexion was less strong initially, but improved after intervention in the form of a specific exercise programme, over the measurement period. A questionnaire disclosed that low back pain is a common complaint of hockey players, but rarely required intensive physical and medical treatment. The term 'hockey player's back' has been coined in recognition of the long flat thoracolumbar spine frequently noted in these subjects. Copyright © 1988 Australian Physiotherapy Association. Published by . All rights reserved.
Full Text Available Expertise development in the massively multiplayer online game World of Warcraft (Blizzard Entertainment, 2004 depends greatly on a player's use of social skills to gain access to expert player groups and accrue social and cultural capital. Drawn from ethnographic research, this paper maps out various forms of expert practice and highlights the social aspects of game play that often eclipse the importance of game-mechanics knowledge. At the time of this research, playing World of Warcraft and developing expertise in the game happened roughly within a two-stage process: (1 leveling up, or advancing one's character or avatar while learning the mechanics of the game, and (2 drawing on social capital gained during the first stage to join a group of up to 40 players to partake in high-end or endgame content.
Schmid, C; Wieczorek, W; Kiesel, N; Weinfurter, H [Sektion Physik, Ludwig-Maximilians-Universitaet, D-80797 Muenchen (Germany); Flitney, A P; Hollenberg, L C L, E-mail: firstname.lastname@example.org [School of Physics, The University of Melbourne, Parkville, VIC 3010 (Australia)
Game theory is central to the understanding of competitive interactions arising in many fields, from the social and physical sciences to economics. Recently, as the definition of information is generalized to include entangled quantum systems, quantum game theory has emerged as a framework for understanding the competitive flow of quantum information. Up till now, only two- and three-player quantum games have been demonstrated with restricted strategy sets. Here, we report the first experiment that implements a four-player quantum minority game over tunable four-partite entangled states encoded in the polarization of single photons. Experimental application of appropriate player strategies gives equilibrium payoff values well above those achievable in the classical game. These results are in excellent quantitative agreement with our theoretical analysis of the symmetric Pareto optimal strategies. Our results demonstrate for the first time how nontrivial equilibria can arise in a competitive situation involving quantum agents.
Drachen, Anders; Thurau, C.; Sifa, R.
patterns in the behavioral data, and developing profiles that are actionable to game developers. There are numerous methods for unsupervised clustering of user behavior, e.g. k-means/c-means, Nonnegative Matrix Factorization, or Principal Component Analysis. Although all yield behavior categorizations......, interpretation of the resulting categories in terms of actual play behavior can be difficult if not impossible. In this paper, a range of unsupervised techniques are applied together with Archetypal Analysis to develop behavioral clusters from playtime data of 70,014 World of Warcraft players, covering a five......The analysis of user behavior in digital games has been aided by the introduction of user telemetry in game development, which provides unprecedented access to quantitative data on user behavior from the installed game clients of the entire population of players. Player behavior telemetry datasets...
Nyberg, Michael Permin; Fiorenza, Matteo; Lund, Anders
PURPOSE: The present study examined whether a period of additional speed endurance training would improve intense intermittent exercise performance in highly trained soccer players during the season and whether the training changed aerobic metabolism and the level of oxidative enzymes in type I...... and II muscle fibers. METHODS: During the last nine weeks of the season, thirteen semi-professional soccer players performed additional speed endurance training sessions consisting of 2-3 sets of 8 - 10 repetitions of 30 m sprints with 10 s of passive recovery (SET). Before and after SET, subjects...... in type I and II fibers did not change. CONCLUSION: In highly trained soccer players, additional speed endurance training is associated with an improved ability to perform repeated high-intensity work. To what extent the training-induced changes in V˙O2 kinetics and mechanical efficiency in type I fibers...
Reeves, Sue; Collins, Kieran
The aim of this study was to investigate the dietary intakes and anthropometric profiles of county and club Gaelic football players and compare them to soccer players and control subjects. Seven-day dietary records were analyzed and anthropometric measurements were taken midway through the Gaelic football competitive season. The county group with a mean height of 1.82 +/- 0.04 m were significantly taller (p soccer players and 159 +/- 8 kJ x kg(-1) x day(-1) for the controls, with 57 +/- 4% and 44.9 +/- 5% of their energy from carbohydrate. The nature of Gaelic football demands a balanced diet, rich in energy and carbohydrate and with adequate calcium is consumed; the subjects needed to increase these dietary components in order to meet the energetic demands of competition and training. Additional nutritional counseling was provided on an individual basis.
We outline the general construction of three-player games with incomplete information which fulfil the following conditions: (i) symmetry with respect to the permutations of players; (ii) the existence of an upper bound for total payoff resulting from Bell inequalities; (iii) the existence of both fair and unfair Nash equilibria saturating this bound. Conditions (i)-(iii) imply that we are dealing with conflicting interest games. An explicit example of such a game is given. A quantum counterpart of this game is considered. It is obtained by keeping the same utilities but replacing classical advisor by a quantum one. It is shown that the quantum game possesses only fair equilibria with strictly higher payoffs than in the classical case. This implies that quantum nonlocality can be used to resolve the conflict between the players.
Rau, Pei-Luen Patrick; Peng, Shu-Yun; Yang, Chin-Chow
Online game addiction is a new mental disorder. This disorder is difficult to describe because of its comprehensive nature. Many online game players have problems controlling their playing time. They cannot stop playing a game that they enjoy. This research surveyed the past literature on "flow" and time disorder theory. A time distortion experiment was conducted. This research invited 64 children, teenagers, and young adults to investigate player skill and playing time effects on online game break-off. The playing experience and degree of time distortion were measured and analyzed. The results showed that both novice and expert online game players were subject to time distortion. The participants had difficulty breaking off from the game without intrusion by others in the real world. This research also suggests eight questions for self-evaluation for online game addiction.
Maughan, R J
To examine the dietary habits of professional soccer players at two Scottish Premier League clubs during the competitive season. A study of the dietary intake of 51 professional soccer players with two different clubs was carried out by the seven day weighed intake method. Physical characteristics of the two groups of players were similar, with only small differences in age and body mass but no difference in height and body fat. Mean (SD) daily energy intake for club A was 11.0 (2.6) MJ, and for club B 12.8 (2.2) MJ. The higher energy intake at club B was largely accounted for by a higher (P macronutrients to total energy intake was broadly similar to that of the general population.
Kayacan, Yildirim; Yildiz, Sedat
The aim of this study was to evaluate heart rate variability (HRV) in professional handball players during rest and following a 5 min mild jogging exercise. For that purpose, electrocardiogram (ECG) of male handball players (N.=12, mean age 25±3.95 years) and sedentary controls (N.=14, mean age 23.5±2.95 years) were recorded for 5 min at rest and just after 5 min of mild jogging. ECGs were recorded and following HRV parameters were calculated: time-domain variables such as heart rate (HR), average normal-to-normal RR intervals, standard deviation of normal-to-normal RR intervals, square root of the mean of the squares of differences between adjacent NN intervals, percentage of differences between adjacent NN intervals that are greater than 50 milliseconds (pNN50), and frequency-domain variables such as very low frequency, low (LF) and high frequency (HF) of the power and LF/HF ratio. Unpaired t-test was used to find out differences among groups while paired t-test was used for comparison of each group for pre- and postjogging HRV. Pearson correlations were carried out to find out the relationships between the parameters. Blood pressures were not different between handball players and sedentary controls but exercise increased systolic blood pressure (Phandball players (Phandball players (Phandball players in response to a mild, short-time (5 min) jogging exercise. However, in sedentary subjects, either the sympathetic regulation of the autonomous nervous system increased or vagal withdrawal occurred.
Charles F. Babbs
Full Text Available To better understand the risk and safety of heading a soccer ball, the author created a set of simple mathematical models based upon Newton�s second law of motion to describe the physics of heading. These models describe the player, the ball, the flight of the ball before impact, the motion of the head and ball during impact, and the effects of all of these upon the intensity and the duration of acceleration of the head. The calculated head accelerations were compared to those during presumably safe daily activities of jumping, dancing, and head nodding and also were related to established criteria for serious head injury from the motor vehicle crash literature. The results suggest heading is usually safe but occasionally dangerous, depending on key characteristics of both the player and the ball. Safety is greatly improved when players head the ball with greater effective body mass, which is determined by a player�s size, strength, and technique. Smaller youth players, because of their lesser body mass, are more at risk of potentially dangerous headers than are adults, even when using current youth size balls. Lower ball inflation pressure reduces risk of dangerous head accelerations. Lower pressure balls also have greater “touch” and “playability”, measured in terms of contact time and contact area between foot and ball during a kick. Focus on teaching proper technique, the re-design of age-appropriate balls for young players with reduced weight and inflation pressure, and avoidance of head contact with fast, rising balls kicked at close range can substantially reduce risk of subtle brain injury in players who head soccer balls.
Munce, Thayne A; Dorman, Jason C; Thompson, Paul A; Valentine, Verle D; Bergeron, Michael F
Football players are subjected to repetitive impacts that may lead to brain injury and neurologic dysfunction. Knowledge about head impact exposure (HIE) and consequent neurologic function among youth football players is limited. This study aimed to measure and characterize HIE of youth football players throughout one season and explore associations between HIE and changes in selected clinical measures of neurologic function. Twenty-two youth football players (11-13 yr) wore helmets outfitted with a head impact telemetry (HIT) system to quantify head impact frequency, magnitude, duration, and location. Impact data were collected for each practice (27) and game (9) in a single season. Selected clinical measures of balance, oculomotor performance, reaction time, and self-reported symptoms were assessed before and after the season. The median individual head impacts per practice, per game, and throughout the entire season were 9, 12, and 252, respectively. Approximately 50% of all head impacts (6183) had a linear acceleration between 10g and 20g, but nearly 2% were greater than 80g. Overall, the head impact frequency distributions in this study population were similar in magnitude and location as in high school and collegiate football, but total impact frequency was lower. Individual changes in neurologic function were not associated with cumulative HIE. This study provides a novel examination of HIE and associations with short-term neurologic function in youth football and notably contributes to the limited HIE data currently available for this population. Whereas youth football players can experience remarkably similar head impact forces as high school players, cumulative subconcussive HIE throughout one youth football season may not be detrimental to short-term clinical measures of neurologic function.
A Los Arcos
Full Text Available The aim of this study was to quantify the seasonal perceived respiratory and muscular training loads (i.e., sRPEres-TL and sRPEmus-TL completed by elite-oriented young professional soccer players. Twentyfour players (20.3 ± 2.0 years belonging to the same reserve team of a Spanish La Liga club participated in this study. Only the players that were available to train for a whole week with the team and also to play the weekly game were considered: Starters, players that participated in the match for at least 45 min and Non- Starters, players that did not participate or played less than 45 minutes in the match. The competitive period was analysed after the division into 5x6-8 week blocks and 35x1 week microcycles. Data were also analysed with respect to number of days before the immediate match. Weekly TL variation across the in-season blocks was trivial-small for both groups except between Block 2 and Block 3 (ES= moderate. Substantial TL differences (ES= small–very likely were found between training days, the TL pattern being a progressive increase up to MD-3 followed by a decrease until MD-1. Except for the match, sRPEres-/sRPEmus-TL was very similar between Starters and Non-Starters. In summary, perceived TL across the season displayed limited variation. Coaches periodized training contents to attain the highest weekly TL 72 hours before the match to progressively unload the players between MD-3 and the match day. The data revealed that the TL arising from the weekly game was solely responsible for the observed higher weekly TL of Starters in comparison with Non-Starters.
Angelova, Mariyana; Bäck, Hanna; Müller, Wolfgang C; Strobl, Daniel
Veto player theory generates predictions about governments' capacity for policy change. Due to the difficulty of identifying significant laws needed to change the policy status quo, evidence about governments' ability to change policy has been mostly provided for a limited number of reforms and single-country studies. To evaluate the predictive power of veto player theory for policy making across time, policy areas and countries, a dataset was gathered that incorporates about 5,600 important government reform measures in the areas of social, labour, economic and taxation policy undertaken in 13 Western European countries from the mid-1980s until the mid-2000s. Veto player theory is applied in a combined model with other central theoretical expectations on policy change derived from political economy (crisis-driven policy change) and partisan theory (ideology-driven policy change). Robust support is found that governments introduce more reform measures when economic conditions are poor and when the government is positioned further away from the policy status quo. No empirical support is found for predictions of veto player theory in its pure form, where no differentiation between government types is made. However, the findings provide support for the veto player theory in the special case of minimal winning cabinets, where the support of all government parties is sufficient (in contrast to minority cabinets) and necessary (in contrast to oversized cabinets) for policy change. In particular, it is found that in minimal winning cabinets the ideological distance between the extreme government parties significantly decreases the government's ability to introduce reforms. These findings improve our understanding of reform making in parliamentary democracies and highlight important issues and open questions for future applications and tests of the veto player theory.
Full Text Available Real Madrid was named as the best club of the 20th century by the International Federation of Football History and Statistics. The aim of this study was to compare if players from Real Madrid covered shorter distances than players from the opposing team. One hundred and forty-nine matches including league, cup and UEFA Champions League matches played by the Real Madrid were monitored during the 2001-2002 to the 2006-2007 seasons. Data from both teams (Real Madrid and the opponent were recorded. Altogether, 2082 physical performance profiles were examined, 1052 from the Real Madrid and 1031 from the opposing team (Central Defenders (CD = 536, External Defenders (ED = 491, Central Midfielders (CM = 544, External Midfielders (EM = 233, and Forwards (F = 278. Match performance data were collected using a computerized multiple-camera tracking system (Amisco Pro®, Nice, France. A repeated measures analysis of variance (ANOVA was performed for distances covered at different intensities (sprinting (>24.0 km/h and high-speed running (21.1-24.0 km/h and the number of sprints (21.1-24.0 km/h and >24.0 km/h during games for each player sectioned under their positional roles. Players from Real Madrid covered shorter distances in high-speed running and sprint than players from the opposing team (p 0.01 from Real Madrid covered shorter distances in high-intensity running and sprint and performed less sprints than their counterparts. Finally, no differences were found in the high-intensity running and sprint distances performed by players from Real Madrid depending on the quality of the opposition.
Heisterberg, Mette F; Fahrenkrug, Jan; Krustrup, Peter; Storskov, Anders; Kjær, Michael; Andersen, Jesper L
The aim of this study was to make a comprehensive gathering of consecutive detailed blood samples from professional soccer players and to analyze different blood parameters in relation to seasonal changes in training and match exposure. Blood samples were collected 5 times during a 6-month period and analyzed for 37 variables in 27 professional soccer players from the best Danish league. Additionally, the players were tested for body composition, V[Combining Dot Above]O2max and physical performance by the Yo-Yo intermittent endurance submax test (IE2). Multiple variations in blood parameters occurred during the observation period, including a decrease in hemoglobin and an increase in hematocrit as the competitive season progressed. Iron and transferrin were stable, whereas ferritin showed a decrease at the end of the season. The immunoglobulin A (IgA) and IgM increased in the period with basal physical training and at the end of the season. Leucocytes decreased with increased physical training. Lymphocytes decreased at the end of the season. The V[Combining Dot Above]O2max decreased toward the end of the season, whereas no significant changes were observed in the IE2 test. The regular blood samples from elite soccer players reveal significant changes that may be related to changes in training pattern, match exposure, or length of the match season. Especially the end of the preparation season and at the end of the competitive season seem to be time points were the blood-derived values indicate that the players are under excessive physical strain and might be more subjected to a possible overreaching-overtraining conditions. We suggest that regular analyses of blood samples could be an important initiative to optimize training adaptation, training load, and game participation, but sampling has to be regular, and a database has to be built for each individual player.
Chin, M K; Wong, A S; So, R C; Siu, O T; Steininger, K; Lo, D T
There is a scarcity of descriptive data on the performance capacity of elite badminton players, whose fitness requirements are quite specific. The purpose of this paper is to investigate the physiological response of elite badminton players in a sport-specific fitness test. Twelve Hong Kong national badminton team players performed a field test on a badminton court. Six light bulbs were connected to a programming device causing individual bulbs to light up in a given sequence. The players were instructed to react to the flashes by running towards them, and striking shuttles mounted in the vicinity of the bulbs. Exercise intensity was controlled by altering the interval between successive lightings. A low correlation (r = 0.65) was found between the results of the field test and the rank-order list of subjects, based on an objective on-field physiological assessment and subjective ranking. This may be explained by the requirements of other factors besides physical fitness which contribute to success in elite level badminton competition. These factors may include, for example, technical skill, mental power, and aesthetic judgements on the court. Maximum mean (s.d.) heart rate data (187(8) beats.min-1) and blood lactate values (10.4(2.9) mmol.l-1) in this study showed that players were under maximal load during the field test. From the testing data, it seems reasonable to speculate that the intensity of level 3 (20 light pulses.min-1; 3.0 s.pulse-1) and level 4 (22 light pulses.min-1; 2.7 s.pulse-1) simulates the requirement of actual games energy expenditure of the Hong Kong badminton players exercising at close to their anaerobic threshold. The results also show that an estimate of fitness can be derived from measurements involving exercise closely resembling that which is specific for the sports activity in question. Improved training advice and guidance may result from such studies. PMID:8800846
Koltai, Miklós; Wallner, Dietmar; Gusztafik, Ádám; Sáfár, Zoltán; Dancs, Henriette; Simi, Helmut; Hagenauer, Marcel; Buchgraber, Anna Maria
The Institute of Sport Science at the University of West-Hungary, and the FH-Joanneum – together with students majoring in sport science – started a collaborative international research aimed at assessing the sport-specific skills of football players. The study closely monitored football players – from leagues at different levels – in terms of choice reaction time, short and long pass skills and agility skills with and without a ball. The most modern device available, the SmartSpeed – a photo...
Conclusion: The study revealed that soccer players with osteitis pubis may have concomitant inguinal hernia, and that osteitis pubis may develop in soccer players who have undergone hernia repair. In addition, more severe osteitis pubis findings on the same side with hernia indicate that the two pathologies occur with common mechanisms. It should not be forgotten that inguinal hernia be considered in the differential diagnosis of osteitis pubis, which it may accompany. Conservative methods are mostly used in the treatment of osteitis pubis, whereas the treatment of inguinal hernia is surgery. If only one entity is diagnosed when both are present, the success of treatment will decrease.
Kolt, G S; Roberts, P D
A volunteer sample of 50 competitive field hockey players completed the Coopersmith Self-esteem Inventory at pre- and postseason and prospectively collected injury data over a 20-wk. season. Multiple regression analysis showed no relationship between scores on Self-esteem and the number of injuries, the participation time affected due to injury, and sex of players. Further multiple regression analysis showed that frequency of the more severe injuries significantly predicted scores on Self-esteem. This finding can be interpreted as evidence of the relationship between low self-esteem and injury in sport.
The Expected-Outcome Model of Two-Player Games deals with the expected-outcome model of two-player games, in which the relative merit of game-tree nodes, rather than board positions, is considered. The ambiguity of static evaluation and the problems it generates in the search system are examined and the development of a domain-independent static evaluator is described. Comprised of eight chapters, this book begins with an overview of the rationale for the mathematical study of games, followed by a discussion on some previous artificial intelligence (AI) research efforts on game-trees. The nex
Yu, J Y; Huang, D F; Li, Y; Zhang, Y T
Hypertension is a common clinical disease and a major risk to human health. Many clinical findings indicate that certain types of music can reduce blood pressure (BP), and music therapy is considered as an important part of anti-hypertension treatment. We integrate our former related research achievement into the new MP3 player, which can also detect the current BP value with a cuffless measurement method. According to the current BP value, the MP3 player selects certain types of music for playing in order to alleviate the hypertension of patients.
Contemporary personal stereo players are compact, easy to use, and provide intense, high-quality sound that can be heard anywhere anytime. The players are reasonable in price, and have become very popular among children and adolescents. Little is known about listening habits among children...... in the belly, and a display on front that shows listening level (Laeq) according to ISO 11904-2. The scale also indicates how long one can listen at that given level without exceeding a workday exposure level of 80 dBA. The manikin has proven useful as a tool for mediation, and may even (in a revised version...
...-OPERATED PHONORECORD PLAYERS § 254.2 Definition of coin-operated phonorecord player. As used in this part..., currency, tokens, or other monetary units or their equivalent; (b) Is located in an establishment making no...
Brito, João; Fontes, Ivo; Ribeiro, Fernando
To investigate the effects of an official soccer match on postural stability in youth elite soccer players.......To investigate the effects of an official soccer match on postural stability in youth elite soccer players....
Raphael Mendes Ritti Dias
Full Text Available During a soccer match, countless movements involving muscular force are performed. While some studies have analyzed the force exerted by soccer players, their results have been divergent, particularly when force has been analyzed with respect to fi eld positions. The objective of this study was to compare peak torque, total muscular work, maximum power and isokinetic fatigue index of the knee fl exor and extensor muscles of soccer players in a variety of fi eld positions. Seventy-eight under-twenty soccer players were classifi ed according to the position they play: goalkeepers (n=7, full backs (n=14, wingers (n=16, defensive midfi elders (n=11, center midfi elders (n=14 and forwards (n=16. The concentric isokinetic force of knee fl exor and extensor muscles was evaluated using an isokinetic dynamometer, Cybex® brand Norm™ 6000 model (CSMI, USA. Data was analyzed in terms of non-parametric statistics and results expressed in medians and semi-interquartile range. The Kruskal-Wallis test was applied and when results were signifi cant to pRESUMO Durante uma partida de futebol são realizados inúmeros movimentos que envolvem a força muscular. Embora alguns estudos tenham analisado a força de jogadores de futebol, os resultados encontrados têm sido controversos, principalmente quando analisada a força em função da posição de jogo. O objetivo deste estudo foi comparar o pico de torque, trabalho muscular total, potência máxima e índice de fadiga isocinético dos músculos fl exores e extensores de joelho de jogadores de futebol que atuam em diferentes posições de jogo. Foram incluídos 78 atletas de futebol, pertencentes à categoria Sub-20, foram agrupados de acordo com a posição em campo de jogo: goleiros (n=7, zagueiros (n=14, laterais (n=16, volantes (n=11, meio campo (n=14 e atacantes (n=16. Foi realizada avaliação da força isocinética concêntrica dos músculos fl exores e extensores de joelho em dinamômetro isocin
Yamashita, Daichi; Asakura, Masaki; Ito, Yoshihiko; Yamada, Shinzo; Yamada, Yosuke
Yamashita, D, Asakura, M, Ito, Y, Yamada, S, and Yamada, Y. Physical characteristics and performance of Japanese top-level American football players. J Strength Cond Res 31(9): 2455-2461, 2017-This study aimed to compare the physical characteristics and performance between top-level nonprofessional football players in Japan and National Football League (NFL) Combine invited players and between top-level and middle-level players in Japan to determine the factors that enhance performance in international and national competitions. A total of 168 American football players (>20 years) in Japan participated in an anthropometric (height and weight) and physical (vertical jump, long jump, 40-yard dash, pro-agility shuttle, 3-cone drill, and bench press repetition test) measurement program based on the NFL Combine program to compete in the selection of candidates for the Senior World Championship. All players were categorized into 1 of the 3 position groups based on playing position: skill players, big skill players, and linemen. Japanese players were additionally categorized into selected and nonselected players for the second tryout. The NFL Combine candidates had significantly better performance than selected Japanese players on all variables except on performance related to quickness among the 3 position groups. Compared with nonselected players, selected Japanese skill players had better performance in the 40-yard dash and bench press test and big skill players had better performance in the vertical jump, broad jump, and 40-yard dash. Selected and nonselected Japanese linemen were not different in any measurements. These results showed the challenges in American football in Japan, which include not only improving physical performance of top-level players, but also increasing the number of football players with good physical performance.
Greciano, Miguel Cristian
This work focuses on the combination of two key concepts: Dynamic Difficulty Adjustment/Adaptation (video games adapting their difficulty according to the in-game performance of players, making themselves easier if the player performs poorly or more difficult if the player performs well) and Collaborative Multiplayer Games (video games where two or more human players work together to achieve a common goal). It considers and analyzes the challenges, potential and possibilities of Dynamic Diffi...
Full Text Available Maintenance of the sporting activity of elite athletes in adapted sports can be difficult if a secondary disorder, such as a pressure ulcer, occurs. Pressure ulcers result from deep tissue injuries by external pressure. The purpose of this study was to use ultrasonography to investigate deep tissue injuries in male wheelchair basketball players of a Japanese national team, and to determine factors associated with the injuries (e.g., body mass index, class of wheelchair basketball, underlying disease, length of athletic career, and whether use of wheelchair is primarily for playing basketball. Twenty male Japanese wheelchair basketball players on the national team for the 2012 London Paralympic Games (12 representative players and eight candidate representative players participated in this study. The sacral region and bilateral ischial regions in each athlete were examined by ultrasonography to detect low-echoic lesions indicative of deep tissue injuries. Nine (45% players had low-echoic lesions, which were detected in 10 of 60 areas. Eight lesions were detected in the sacral region and two lesions were detected in the ischial region. More players with spinal cord injury had low-echoic lesions [9 (69.2% of 13 players], compared to players with skeletal system disease [0 (0% of 7 players, p = 0.002]. Players who used a wheelchair in daily life were more likely to have low-echoic lesions [8 (66.74% of 12 players], compared to players who primarily used a wheelchair for playing basketball [1 (12.5% of 8 players, p = 0.010]. Deep tissue injuries were detected in 45% of male Japanese wheelchair basketball players on the national team. Players with spinal cord injury and players who used a wheelchair in daily life were more likely to have deep tissue injuries, particularly in the sacral region. The lesions were small, but a periodic medical check should be performed to maintain athletes' sporting life.
You, Fang; Liu, Jianping; Guan, Xinjian; Wang, Jianmin; Zheng, Zibin; Tam, Peter
Massively multiplayer online role-playing games (MMORPGs) have great potential as sites for research within the social and human-computer interaction. In the MMORPGs, a stability player taxonomy model is very important for game design. It helps to balance different types of players and improve business strategy of the game. The players in mobile MMORPGs are also connected with social networks; many studies only use the player's own attributes statistics or questionnaire survey method to predi...
Lanzotti, A.; Costabile, G.; Annino, G.; Amodeo, G.; Odenwald, S.
The risk of injury following a player's impact with objects in sport facilities is a growing problem, as shown by serious accidents that happen when players have head impacts with obstacles and barriers installed around the play area. At present, no experimental data are available about the kinematics of football (soccer) players during a running-out of playing areas scenario. Experimental tests on a sample of 14 skilled football players, aged between 17 and 19 years, were conducted to invest...
Hidalgo y Terán Elizondo, Roberto; Martín Bermudo, Francisco Manuel; Peñaloza Méndez, Ricardo; Berná Amorós, Genoveva; Lara Padilla, Eleazar; Berral de la Rosa, Francisco José
Introduction: nutritional intake and status of soccer players has attracted not much research attention. Many soccer players follow an inadequate nutritional intake and have a poor nutritional status. This is relevant in youngsters soccer players, in order to improve performance and promote healthy dietary practices. Aims: analyze anthropometric characterizes, evaluate nutritional intake and status, dietary habits and pre- and post-exercise meals in elite teenagers soccer players. Methods: se...
Stornes, Tor; Ommundsen, Yngvar
The aim of this study was to investigate the relationships between achievement goals, perceptions of motivational climate and sportspersonship in a sample of young male Norwegian handball players. A cross-sectional study of 440 male handball players aged from 14 to 16 was conducted, in which the players responded to a questionnaire measuring…
Barrault, Servane; Varescon, Isabelle
Background and aims Online gambling appears to have special features, such as anonymity, speed of play and permanent availability, which may contribute to the facilitation and increase in gambling practice, potentially leading to problem gambling. The aims of this study were to assess sociodemographic characteristics, gambling practice and impulsive sensation seeking among a population of regular poker players with different levels of gambling intensity and to compare online and live players. Methods 245 regular poker players (180 online players and 65 live players) completed online self-report scales assessing sociodemographic data, pathological gambling (SOGS), gambling practice (poker questionnaire) and impulsive sensation seeking (ImpSS). We used SOGS scores to rank players according to the intensity of their gambling practice (non-pathological gamblers, problem gamblers and pathological gamblers). Results All poker players displayed a particular sociodemographic profile: they were more likely to be young men, executives or students, mostly single and working full-time. Online players played significantly more often whereas live players reported significantly longer gambling sessions. Sensation seeking was high across all groups, whereas impulsivity significantly distinguished players according to the intensity of gambling. Discussion Our results show the specific profile of poker players. Both impulsivity and sensation seeking seem to be involved in pathological gambling, but playing different roles. Sensation seeking may determine interest in poker whereas impulsivity may be involved in pathological gambling development and maintenance. Conclusions This study opens up new research perspectives and insights into preventive and treatment actions for pathological poker players. PMID:28092187
Vollstadt-Klein, Sabine; Grimm, Oliver; Kirsch, Peter; Bilalic, Merim
Whereas a lot of studies examine cognitive processes in chess players, personality profiles of elite chess players are still not described well. The aim of this study was to examine personality of strong chess experts and its influence on chess skill. We tested elite male and female chess players with Freiburg Personality Inventory Revised…
Stein, Josh G; Gabbett, Tim J; Townshend, Andrew D; Dawson, Brian T
To investigate the relationship between physical qualities and match activity profiles of recreational Australian football players. Prospective cohort study. Forty players from three recreational Australian football teams (Division One, Two and Three) underwent a battery of fitness tests (vertical jump, 10 and 40 m sprint, 6 m × 30 m repeated sprint test, Yo-Yo intermittent recovery level Two and 2-km time trial). The activity profiles of competitive match-play were quantified using 10-Hz Global Positioning System units. Division One players possessed greater maximum velocity, Yo-Yo level Two and 2-km time trial performances than Division Two and Three players. In addition, Division One players covered greater relative distance, and relative distances at moderate- and high-intensities during match-play than Division Two and Three players. Division Two players had better 2-km time trial performances than Division Three players. Positive associations (P football players competing at a higher level exhibit greater physical qualities and match-play activity profiles than lesser-skilled recreational players. Acceleration and maximum velocity, 2-km time trial and Yo-Yo level Two performances discriminate between players of different playing levels, and are related to physical match performance in recreational Australian football. The development of these qualities is likely to contribute to improved match performance in recreational Australian football players. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Skaza, Robert J.
This basic qualitative study of high school football coach-player relationships explores the players' perceptions of these relationships, specifically the perceptions the players have of how these relationships influenced their lives. This study allowed the researcher to examine the characteristics of high school football coaches as they relate to…
The purpose of this study is to compare speed, agility, anaerobic strength and some anthropometric characteristics in male football and futsal players. The sample of the study is composed of male futsal team players of Aydin Adnan Menderes University (19-24 aged) (n = 12) and Aydin Merkez Yeniköy Football Club players (19-24 aged) (n = 12). Within…
This study aimed at identifying the level of physical and body self-esteem among the female futsal - football players at Jordanian clubs. The sample of the study was composed of (38) female players among the Jordanian clubs' players of futsal-football who were chosen randomly out of the study community, and the self-esteem scale was used,…
Full Text Available Based on the structure competition activities, and its character can be defined as a hypothetical model of the anthropological characteristics of football players of different gaming positions. Based on hypothetical models of different football players' position can make a division into two groups of players based on game systems that are commonly used in modern football, which is 4-4-2, and the common anthropological characteristics, structure and nature of activities carried out by during the game, so the first group consists of players with smaller volumes of engagement in the game (goalkeeper, two central defenders and two strikers and the second group 190 CRNOGORSKA SPORTSKA AKADEMIJA, „Sport Mont“ časopis br. 31,32,33. consists of players with greater scope to engage in the game (two foreign players and four defensive midfielder (midfielder . The aim is to determine the difference between players of different players' positions on the basis of some basic and specific motor abilities. The sample of 206 football players aged 18 ± 0.5 years is divided into 5 subsamples according to examinees gaming position: forwarders (45, midfield players (47, defenders (41, central defenders (44 and goalkeepers (29. The battery of 16 tests (in which the results are expressed in distance and time - metric. It can be concluded that there are differences between players of different players' positions on the team in relation to the basic and specific motor skills.
Full Text Available We study the problem of finding optimal paths in network games with p players. Some polynomial-time algorithms for finding optimal paths and optimal by Nash strategies of the players in network games with p players are proposed.
Newsham-West, R; Button, C; Milburn, P D; Mündermann, A; Sole, G; Schneiders, A G; Sullivan, S J
To profile training habits and injuries in football players participating in a national Masters tournament. A cross-sectional retrospective study design was used to survey male football players attending the 2008 New Zealand Masters Games. Information regarding player demographics, football injuries, football related training, and risk factors for injury were collected. 199 Players were recruited, with a median age of 44 yrs (range 35-73) and a median football playing history of 15 yrs (range 0-66). Irrespective of age, 112 (84%) players included a warm-up and 104 (78%) included a stretching regime in their regular training programme. In the 12 months prior to the tournament, 128 football related injuries were reported by 93 players (64 injuries/100 players or 46 injured players/100 players). The most frequently injured region was the lower limb; specifically the lower leg (n=23), ankle (n=18), hamstring (n=17), knee (n=15), and Achilles tendon (n=15). This study provides a preliminary insight into the training habits and injury profiles of Masters football players. Despite all players including some form of injury prevention strategy in their training, a significant number of players experienced an injury in the 12 months prior to the tournament.
Afyon, Yakup Akif
Core trainings have been widely used by trainers recently in order to improve performance of soccer players. In this context, the aim of this study is to examine the effect of core training on some motoric capabilities of 16 years old soccer players. Thirty certified soccer players who were 16 years old from B.B. Bodrumspor Club in 2013-2014…
Gencer, Yildirim Gokhan; Coskun, Funda; Sarikaya, Mucahit; Kaplan, Seyhmus
The aim of this study is to investigate the effect of intensive basketball competitions (10 official basketball games in 12 days intensive competition period) on blood parameters of basketball players. Blood samples were taken from the basketball players of the university team. The players were training regularly and they had no regular health…
Couppé, Christian; Kongsgaard, M; Aagaard, Per
The aim of this study was to examine the structural and mechanical properties of the patellar tendon in elite male badminton players with and without patellar tendinopathy. Seven players with unilateral patellar tendinopathy (PT group) on the lead extremity (used for forward lunge) and nine players...
..., Including Mobile Phones, Portable Music Players, and Computers; Notice of Investigation AGENCY: U.S... music players, and computers, by reason of infringement of certain claims of U.S. Patent Nos. 6,714,091... importation of certain electronic devices, including mobile phones, portable music players, or computers that...
Full Text Available We compared the serve toss of different types of serve when tennis players served from the ad-court. They used different spin on the ball and various ball placements in the opponent’s service box. Our aim was to compare the toss in different types of serve between a competitive (local tournament player and a professional player, from the point of view of the receiving player, when they served from the ad-court. One professional and one competitive tennis player (both right handed were observed while serving different types of serve to various locations of the opponent’s service box. We used a high-speed camera, which was placed opposite to the server in the position of a receiving player. The results showed that the players do not use the same toss for each type of serve. The professional player had a bigger range of racket-ball contact point on horizontal axis (32 cm of the various types of first serves, compared to the competitive player (only 24 cm. The toss of the kick serve had similar characteristics between both players (the racket-ball contact point was observed to be mostly to the right, from the view of receiver. Neither the professional nor the competitive player showed a stable profile of toss. In some cases, the receiving players could anticipate the type of the serve from the server’s toss.
Chisholm, J; Hickey, C.; Theeuwes, J.; Kingstone, A.
Recent studies indicate that playing action video games improves performance on a number of attention-based tasks. However, it remains unclear whether action video game experience primarily affects endogenous or exogenous forms of spatial orienting. To examine this issue, action video game players
Repovich, Wendy E. S.; Babcock, Garth J.
The purpose of this study was to determine if body composition and blood pressure (BP), two markers for Metabolic Syndrome (MetS), were correlated in college football players. Height, weight, BMI, systolic (SBP) and Diastolic (DBP) blood pressure and body composition (three measures) were assessed in a Division IAA football team (N = 55). Data…
Vogel, I.; Brug, J.; Ploeg, C.P.B. van der; Raat, H.
Analogue to occupational noise-induced hearing loss, MP3-induced hearing loss may be evolving into a significant social and public health problem. To inform prevention strategies and interventions, this study investigated correlates of adolescents' risky MP3-player listening behavior primarily
Vogel, Ineke; Brug, Johannes; Van Der Ploeg, Catharina P. B.; Raat, Hein
Analogue to occupational noise-induced hearing loss, MP3-induced hearing loss may be evolving into a significant social and public health problem. To inform prevention strategies and interventions, this study investigated correlates of adolescents' risky MP3-player listening behavior primarily informed by protection motivation theory. We invited…
Marvel, Michele D.
Understanding the factors that affect participation in online games will help educational game designers develop games that maximize participation. This study investigated whether introversion or extroversion, player motivation, and gender affected participation in online games. Participants (n = 400) completed a 50-item questionnaire about…
Couceiro, Micael S.; Clemente, Filipe M.; Martins, Fernando M. L.
Accurately retrieving the position of football players over time may lay the foundations for a whole series of possible new performance metrics for coaches and assistants. Despite the recent developments of automatic tracking systems, the misclassification problem ( i.e., misleading a given player by another) still exists and requires human operators as final evaluators. This paper proposes an adaptive fractional calculus (FC) approach to improve the accuracy of tracking methods by estimating the position of players based on their trajectory so far. One half-time of an official football match was used to evaluate the accuracy of the proposed approach under different sampling periods of 250, 500 and 1000 ms. Moreover, the performance of the FC approach was compared with position-based and velocity-based methods. The experimental evaluation shows that the FC method presents a high classification accuracy for small sampling periods. Such results suggest that fractional dynamics may fit the trajectory of football players, thus being useful to increase the autonomy of tracking systems.
Roberts, Ross; Woodman, Tim; Lofthouse, Sian; Williams, Lucy
Research on motivational climates consistently demonstrates that mastery-focused climates are associated with positive outcomes and ego-involving performance climates lead to maladaptive outcomes. However, the role of personality within such a framework has been largely ignored. To redress this imbalance, we examined the potential role of narcissism in moderating the effects of different motivational climates on leader-inspired extra effort in training. Training is where rugby players spend most of their rugby time and we were keen to examine the combination of personality and climate that might maximise the yield of such training environments. Female rugby players (n = 126) from 15 clubs completed measures of narcissism, motivational climate and effort. Moderated regression analyses revealed that narcissism moderated the relationship between motivational climate and effort. Increases in either performance or mastery climates were associated with increases in effort for narcissists; no such relationship was revealed for low narcissists. The findings demonstrate the importance of considering personality within rugby training environments, as it is clear that not every player will respond the same way to specific training conditions. Coaches who understand this and are able to tailor individualised motivational climates will likely gain the greatest benefits from their different players.
Almeira, Nahuel; Schaigorodsky, Ana L; Perotti, Juan I; Billoni, Orlando V
Chess is an emblematic sport that stands out because of its age, popularity and complexity. It has served to study human behavior from the perspective of a wide number of disciplines, from cognitive skills such as memory and learning, to aspects like innovation and decision-making. Given that an extensive documentation of chess games played throughout history is available, it is possible to perform detailed and statistically significant studies about this sport. Here we use one of the most extensive chess databases in the world to construct two networks of chess players. One of the networks includes games that were played over-the-board and the other contains games played on the Internet. We study the main topological characteristics of the networks, such as degree distribution and correlations, transitivity and community structure. We complement the structural analysis by incorporating players' level of play as node metadata. Although both networks are topologically different, we show that in both cases players gather in communities according to their expertise and that an emergent rich-club structure, composed by the top-rated players, is also present.
Visscher, C; Elferink-Gemser, MT; Lemmink, KAPM
The purpose of this study, in which 113 talented Youth soccer players (M = 16.0 yr., SD = 15), selected by their age and level of performance participated, was to investigate interval endurance capacity needed to play at the highest level of competition in the age-category 12 through 18.
Alberts, G.; Oldenziel, R.; Alberts, G.; Oldenziel, R.
Playfulness was at the heart of how European players appropriated microcomputers in the last quarter of the twentieth century. Although gaming has been important for computer development, that is not the subject of Hacking Europe. Our book’s main focus is the playfulness of hacker culture. The
Holt, Nicholas L.; Berg, Kylie-Joy; Tamminen, Katherine A.
The purpose of this study was to examine patterns of appraisal, coping, and coping effectiveness in sport. Ten players from a collegiate female volleyball team were interviewed on two occasions, first in the week before a provincial final playoff tournament and in the week following the tournament. Data were transcribed verbatim and subjected to…
Full Text Available This article reports on role player expectations regarding the education of nursing research. The importance of the role player expectations are two-fold: firstly as a factor in the external environment influencing and guiding the formulation phase of the development of standards and secondly, due to the clear indications of problems regarding nursing research in the nursing profession in literature. The role player expectations were elicited using a qualitative, exploratory and contextual design. The role player population included nurse educators, nurses in managerial, clinical and research positions, students and the medical profession. The data was gathered using the naïve sketches and qualitative data analysis was done using Morse & Field’s approach (1996:103-107 in combination with Tesch’s data analysis approach as cited by Creswell (1994:154-156. Sixty initial categories were narrowed down to six final categories, which are the research learning programme, personnel, students, departmental policies, funding and support systems.
Abbey, Elizabeth Lea; Wright, Cynthia Joy; Kirkpatrick, Christina M
Participation in collegiate American football is physically demanding and may have long-term health implications, particularly in relation to cardiovascular and neurological health. National Collegiate Athletic Association (NCAA) Division III (DIII) football players are a relatively unstudied population, particularly in terms of their dietary habits and knowledge. The aim of the present study was to descriptively evaluate the dietary intake of DIII football players including a subset of linemen and assess the nutritional knowledge and sources of information of these athletes. The study sample was 88 DIII football players including a subset of nine linemen. All participants completed a food frequency questionnaire, and a nutritional knowledge questionnaire that included a quiz and questions about their main sources of nutrition information. Heights and body masses were also recorded. The linemen submitted written 3-day diet records for assessment of their dietary intake. Of the 88 participants, >50% reported consuming starches/grains, meat and dairy daily, but football players had dietary habits that may both mitigate and increase their risk of chronic diseases. These athletes have room to improve their nutrition knowledge. Their reliance on athletic team staff for nutrition guidance highlights the importance of nutrition education for both athletes and staff and the potential role of a registered dietitian nutritionist.
Heijne, Norbert; Bakkes, Sander
To contribute to the domain of player experience research, this paper presents a new PCG environment with a relatively wide expressive range that builds upon the iconic The Legend of Zelda: A Link to the Past action-RPG game; it contributes by providing the openly-available Procedural Zelda
van den Brink, J.R.; van der Laan, G.; Vasil'ev, V.
In many applications of cooperative game theory to economic allocation problems, such as river-, polluted river- and sequencing games, the game is totally positive (i.e., all dividends are nonnegative), and there is some ordering on the set of the players. A totally positive game has a nonempty
Ramasamy, Mouli; Harbaugh, Robert E.; Varadan, Vijay K.
Football players are more to violent impacts and injuries more than any athlete in any other sport. Concussion or mild traumatic brain injuries were one of the lesser known sports injuries until the last decade. With the advent of modern technologies in medical and engineering disciplines, people are now more aware of concussion detection and prevention. These concussions are often overlooked by football players themselves. The cumulative effect of these mild traumatic brain injuries can cause long-term residual brain dysfunctions. The principle of concussion is based the movement of the brain in the neurocranium and viscerocranium. The brain is encapsulated by the cerebrospinal fluid which acts as a protective layer for the brain. This fluid can protect the brain against minor movements, however, any rapid movements of the brain may mitigate the protective capability of the cerebrospinal fluid. In this paper, we propose a wireless health monitoring helmet that addresses the concerns of the current monitoring methods - it is non-invasive for a football player as helmet is not an additional gear, it is efficient in performance as it is equipped with EEG nanosensors and 3D accelerometer, it does not restrict the movement of the user as it wirelessly communicates to the remote monitoring station, requirement of individual monitoring stations are not required for each player as the ZigBee protocol can couple multiple transmitters with one receiver. A helmet was developed and validated according to the above mentioned parameters.
The straight and cross court drives were the most frequent strokes used by both genders, with more on the backhand side. The drop shot and straight drives contributed to most winners for the men and women respectively. Most winners were produced by the players when they occupied the middle areas of the court.
Strategies for a nutrition education as applied to individual soccer players provide a key to guiding them towards appropriate food selection. Scientific investigations have associated energy requirements, composition of the diet and carbohydrate intake with muscle glycogen storage, and adequacy of fluids with optimal athletic performance. In general, soccer players appear to consume adequate energy but low carbohydrate diets. The training diet should be comprised of 55-65% carbohydrate, 12-15% protein and less than 30% fat. The goal of the training diet is to provide adequate energy for weight maintenance, and 7-10 g of carbohydrate per kg body weight for maximizing glycogen storage. Nutritional needs for competition include eating prior to and after matches. Consumption of carbohydrate-rich foods for energy needs and glycogen resynthesis are key behaviours soccer players need to focus on daily. Qualified dietitians should be on hand to provide personal nutrition counselling, carbohydrate resource lists and education on food labels as simple and quick nutrition education strategies to guide soccer players, their parents, coaches and trainers towards improved food selections.
Manasse-Cohick, Nancy J.; Shapley, Kathy L.
This survey study compared high school football players' knowledge and attitudes about concussion before and after receiving concussion education. There were no significant changes in the Concussion Attitude Index. Results revealed a statistically significant difference in the athletes' scores for the Concussion Knowledge Index, "t"(244)…
Janssen, J.H.; Westerink, J.H.D.M.; van den Broek, Egon
Affective computing is embraced by many to create more intelligent systems and smart environments. In this thesis, a specific affective application is envisioned: an affective physiological music player (APMP), which should be able to direct its user's mood. In a first study, the relationship
Background: Sport is a compulsory activity in schools in South Africa. Female learners participating in soccer are more vulnerable to injuries than males. Objective: This study determined the epidemiology of injuries in female high school soccer players. Methods: A cross sectional survey captured the epidemiology of ...
Park, Hyunsoo; Kim, Kyung-Joong
The iterated prisoner's dilemma (IPD) is well known within the domain of game theory. Although it is relatively simple, it can also elucidate important problems related to cooperation and trust. Generally, players can predict their opponents' actions when they are able to build a precise model of their behavior based on their game playing experience. However, it is difficult to make such predictions based on a limited number of games. The creation of a precise model requires the use of not only an appropriate learning algorithm and framework but also a good dataset. Active learning approaches have recently been introduced to machine learning communities. The approach can usually produce informative datasets with relatively little effort. Therefore, we have proposed an active modeling technique to predict the behavior of IPD players. The proposed method can model the opponent player's behavior while taking advantage of interactive game environments. This experiment used twelve representative types of players as opponents, and an observer used an active modeling algorithm to model these opponents. This observer actively collected data and modeled the opponent's behavior online. Most of our data showed that the observer was able to build, through direct actions, a more accurate model of an opponent's behavior than when the data were collected through random actions.
Chelly, Mohamed Souhaiel; Hermassi, Souhail; Aouadi, Ridha; Khalifa, Riadh; Van den Tillaar, Roland; Chamari, Karim; Shephard, Roy J
The purposes of this study were to examine the activity profile of elite adolescent players during regular team handball games and to compare the physical and motor performance of players between the first and second halves of a match. Activity patterns (video analysis) and heart-rate (HR) responses (telemetry) were monitored in top national-division adolescent players (18 men, aged 15.1 ± 0.6 years) throughout 6 regulation games (25-minute halves with a 10-minute interval). The total distance covered averaged 1,777 ± 264 m per game (7.4% less in the second than in the first half, p > 0.05). Players ran 170 ± 24 m at high intensity and 86 ± 12 m at maximal speed, with 32 ± 6 bouts of running (duration 2.3 ± 0.3 seconds) at speeds > 18 km·h(-1); they stood still for 16% of the playing time. The mean HR during play was 172 ± 2 b·min(-1) (82 ± 3% of maximal HR). Blood lactate concentrations at the end of the first and second halves were 9.7 ± 1.1 and 8.3 ± 0.9 mmol·L(-1), respectively (difference p game by modifying playing tactics and maximizing both aerobic and anaerobic fitness during training sessions.
Handziska, E; Handziski, Z; Gjorgoski, I; Dalip, M
The relationship between somatotype and cortisol and adrenocorticotropic (ACTH) hormone concentrations at rest or after exercise in adolescent soccer players at different time points throughout a soccer season is not understood. Therefore, the aim of this study was to examine the relationship between somatotype and cortisol and ACTH concentrations at rest and after exercise in adolescent soccer players at different time points during a soccer season. During the first 4 months of the soccer season, 47 soccer players (between 15-17 years of age) were tested at three different time points including at baseline, after 6 weeks, and at the end of 4 months. Testing included anaerobic threshold (AnT, km/h) and maximal speed of running (Max, km/h) were measured with Conconi protocol on treadmill. Before and after a maximal exercise Test, plasma levels of cortisol (ug/dL) and ACTH (pg/ml) were assessed by chemiluminometry enzyme amplificated method. Heath-Carter anthropometric somatotype model was used to determine 13 elements of somatotype. Descriptive statistics and multiple regression were used for statistical analysis (Psoccer training process could indicate a stagnation of training process, accordingly with insignificant changes of AnT. The significant correlations of some somatotypes with stress hormonal responses could only suggest that the somatotype characteristics of young soccer players could be of interest in process of selection and planning of soccer training process with an essential need for more studies.
Bakker, A.B.; Oerlemans, Wido; Demerouti, E.; Bruins Slot, B.; Karamat Ali, D.
Objective: The present study examines the relationship between environmental resources (autonomy,social support from the coach, and performance feedback), flow, and performance among young talented soccer players. Design: The design was non-experimental and involved both self- and coach-rated
Drawer, Scott; Eager, Robin; Taylor, Neil; Cook, Christian
The purpose of this study was to quantify movement demands of elite international age grade (U20) rugby union players during competitive tournament match play. Forty elite professional players from an U20 international performance squad were monitored using 10Hz global positioning systems (GPS) during 15 international tournament matches during the 2014/15 and 2015/16 seasons. Data on distances, velocities, accelerations, decelerations, high metabolic load (HML) distance and efforts, and number of sprints were derived. Data files from players who played over 60 min (n = 161) were separated firstly into Forwards and Backs, and more specifically into six positional groups; FR—Front Row (prop & hooker), SR—Second Row, BR—Back Row (Flankers & No.8), HB—Half Backs (scrum half & outside half), MF—Midfield (centres), B3 –Back Three (wings & full back) for match analysis. Analysis revealed significant differences between forwards and backs positions. Backs scored higher on all variables measured with the exception of number of moderate accelerations, decelerations (no difference). The centres covered the greatest total distance with the front row covering the least (6.51 ± 0.71 vs 4.97 ± 0.75 km, p rugby union players specific to positional roles. PMID:27055230
Song, In Sup; Lee, Jong Ik; Kwak, Byeung Kook; Shim, Hyung Jin; Lee, Jong Beum; Lee, Yong Chul; Kim, Kun Sang; Seo, Kyung Mook
We aimed to know the prevalence of abnormal meniscal signal on MR imaging in asymptomatic soccer players and its radiologic significance. Using T1 and gradient echo T2 weighted sagittal and coronal MR image, 48 knees in twenty-four full time soccer players were evaluated for the meniscal abnormalities, the status of ligament and existence of joint effusion. Meniscal abnormalities were interpreted using grading system of Lotysch. By using Chi-square method. We analyzed the existence of joint effusion could divide the healing state and healed state of the meniscus. The prevalence of Grade 2 and more and Grade 3 were 42% and 39% of asymptomatic knees. In the 24 knees with meniscus tear, nine of the 14 asymptomatic knee showed effusion while eight of the 10 symptomatic knee did. Of 24 knees with meniscal tear, only eleven knees were related to previous history of major knee trauma. The prevalence of meniscal abnormalities on MR imaging in asymptomatic soccer players was higher (grade 3: 39%) than we expected. The joint effusion was not helpful to divide the healing state and healed state of the meniscus. So we suggest baseline MR imaging in the athletes who have been using the knee vigorously could give decisive information for the interpretation of subsequent MRI that may be performed when the players wounded
Mara, Jocelyn K; Thompson, Kevin G; Pumpa, Kate L; Ball, Nick B
To investigate the variation in training demands, physical performance, and player well-being across a women's soccer season. Seventeen elite female players wore GPS tracking devices during every training session (N=90) throughout 1 national-league season. Intermittent high-speed-running capacity and 5-, 15-, and 25-m-sprint testing were conducted at the beginning of preseason, end of preseason, midseason, and end of season. In addition, subjective well-being measures were self-reported daily by players over the course of the season. Time over 5 m was lowest at the end of preseason (mean 1.148 s, SE 0.017 s) but then progressively deteriorated to the end of the season (Pperformance over 15 m improved by 2.8% (P=.013) after preseason training, while 25-m-sprint performance peaked at midseason, with a 3.1% (P=.05) improvement from the start of preseason, before declining at the end of season (P=.023). Training demands varied between phases, with total distance and high-speed distance greatest during preseason before decreasing (Pphysical performance in elite female soccer players allow coaches to ensure that training periodization goals are being met and related positive training adaptations are being elicited.
Wieczorek, Marta; Wiliński, Wojciech; Struzik, Artur; Rokita, Andrzej
Amputee soccer is one of the types of soccer designed for the disabled, especially those who have undergone amputations, as well as those with extremity dysfunction. The objective of the study was to find the relationship between hand grip strength and sprint time in amputee soccer players. Thirteen field amputee soccer players participated in the study. A SAEHAN hydraulic hand dynamometer manufactured by Jamar was used for hand grip strength measurements. The sprint running test was conducted over a distance of 30 m. The Fusion Smart Speed System was employed for running time measurements. No statistically significant relationships were found between hand grip strength of the left or right hand, and sprint times over 1, 5, 10, 15, 20, 25 and 30 m. Analysis of the running velocity curve of the subjects showed an interesting profile characterized by a 15 meter-long acceleration phase and a significant velocity increase over a distance of 20 - 25 m. The study suggests that there is no relationship between hand grip strength and sprint effectiveness in amputee soccer players. The specificity of locomotion with the use of elbow crutches among elite Polish amputee soccer players probably accounts for the profile of the sprint velocity curve. Extension of the acceleration phase in the sprint run and a velocity increase in the subsequent part of the run were observed.
Full Text Available Amputee soccer is one of the types of soccer designed for the disabled, especially those who have undergone amputations, as well as those with extremity dysfunction. The objective of the study was to find the relationship between hand grip strength and sprint time in amputee soccer players. Thirteen field amputee soccer players participated in the study. A SAEHAN hydraulic hand dynamometer manufactured by Jamar was used for hand grip strength measurements. The sprint running test was conducted over a distance of 30 m. The Fusion Smart Speed System was employed for running time measurements. No statistically significant relationships were found between hand grip strength of the left or right hand, and sprint times over 1, 5, 10, 15, 20, 25 and 30 m. Analysis of the running velocity curve of the subjects showed an interesting profile characterized by a 15 meter-long acceleration phase and a significant velocity increase over a distance of 20 – 25 m. The study suggests that there is no relationship between hand grip strength and sprint effectiveness in amputee soccer players. The specificity of locomotion with the use of elbow crutches among elite Polish amputee soccer players probably accounts for the profile of the sprint velocity curve. Extension of the acceleration phase in the sprint run and a velocity increase in the subsequent part of the run were observed.
Keller, Beat; Krattinger, Simon G.
Race-specific resistance genes represent essential genetic sources in crop breeding. Map-based cloning of the wheat Stb6 gene against Zymoseptoria tritici identified a wall-associated receptor kinase-like protein as a novel player in race
Background: Being overhead athletes, water polo players can present with muscular imbalances of the shoulder, between the internal rotators (IR) and external rotators (ER), leading to changes in posture and an increased risk of injury. Objectives: To assess posture and isokinetic shoulder strength of female club-level ...
Full Text Available Past theory and research view reciprocal resource sharing as a fundamental building block of human societies. Most studies of reciprocity dynamics have focused on trading among individuals in laboratory settings. But if motivations to engage in these patterns of resource sharing are powerful, then we should observe forms of reciprocity even in highly structured group environments in which reciprocity does not clearly serve individual or group interests. To this end, we investigated whether patterns of reciprocity might emerge among teammates in professional basketball games. Using data from logs of National Basketball Association (NBA games of the 2008-9 season, we estimated a series of conditional logistic regression models to test the impact of different factors on the probability that a given player would assist another player in scoring a basket. Our analysis found evidence for a direct reciprocity effect in which players who had "received" assists in the past tended to subsequently reciprocate their benefactors. Further, this tendency was time-dependent, with the probability of repayment highest soon after receiving an assist and declining as game time passed. We found no evidence for generalized reciprocity - a tendency to "pay forward" assists - and only very limited evidence for indirect reciprocity - a tendency to reward players who had sent others many assists. These findings highlight the power of reciprocity to shape human behavior, even in a setting characterized by extensive planning, division of labor, quick decision-making, and a focus on inter-group competition.
Willer, Robb; Sharkey, Amanda; Frey, Seth
Past theory and research view reciprocal resource sharing as a fundamental building block of human societies. Most studies of reciprocity dynamics have focused on trading among individuals in laboratory settings. But if motivations to engage in these patterns of resource sharing are powerful, then we should observe forms of reciprocity even in highly structured group environments in which reciprocity does not clearly serve individual or group interests. To this end, we investigated whether patterns of reciprocity might emerge among teammates in professional basketball games. Using data from logs of National Basketball Association (NBA) games of the 2008-9 season, we estimated a series of conditional logistic regression models to test the impact of different factors on the probability that a given player would assist another player in scoring a basket. Our analysis found evidence for a direct reciprocity effect in which players who had "received" assists in the past tended to subsequently reciprocate their benefactors. Further, this tendency was time-dependent, with the probability of repayment highest soon after receiving an assist and declining as game time passed. We found no evidence for generalized reciprocity - a tendency to "pay forward" assists - and only very limited evidence for indirect reciprocity - a tendency to reward players who had sent others many assists. These findings highlight the power of reciprocity to shape human behavior, even in a setting characterized by extensive planning, division of labor, quick decision-making, and a focus on inter-group competition.
Race-specific resistance genes represent essential genetic sources in crop breeding. Map-based cloning of the wheat Stb6 gene against Zymoseptoria tritici identified a wall-associated receptor kinase-like protein as a novel player in race-specific disease resistance.
Traumatic iliopsoas haematoma is a serious complication of haemorrhage disorders rarely seen in young healthy athletes. It is mostly described in patients on anticoagulant therapy and commonly associated with various degrees of femoral nerve palsy. A 22-year-old male rugby player presented with severe onset of pain in ...
The aim of this study was to establish preliminary South African high school rugby norms for the BMSQ. The sample consisted of 152 male high school rugby players from two schools in the Ethekwini region. Preliminary norms are presented in the form of means and standard deviations. Results are compared with those of ...
Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 6. The Major Players in Adaptive Immunity - Cell-mediated Immunity. Asma Ahmed Banishree Saha Anand Patwardhan Shwetha Shivaprasad Dipankar Nandi. General Article Volume 14 Issue 6 June 2009 pp 610-621 ...
This article investigates self-reported music learning experiences of 21 older amateur pianists and electronic keyboard players. Significant changes in their lives and the encouragement of friends were catalysts for returning to or taking up a keyboard instrument as an adult, although not all returners had positive memories of learning a keyboard…
Perception of cohesion and imagery use among 45 elite team sport players in Botswana were assessed with the Group Environment Questionnaire (Carron et al., 1985) and the Sport Imagery Questionnaire (Hall et al., 1998) to determine whether a relationship exists between the variables, and whether imagery use will ...
Kontos, Anthony P; Elbin, R J; Sufrinko, Alicia; Dakan, Scott; Bookwalter, Kylie; Price, Ali; Meehan, William P; Collins, Michael W
Ice hockey is a fast-paced collision sport that entails both intentional (ie, body checking) and incidental contact that may involve the head. The objective of this study was to determine the incidence of concussions in relation to games/practices and age among competition-level youth ice hockey players (ages 12-18 years). Participants included 397 youth ice hockey players from Western Pennsylvania; Boston, Massachusetts; and Birmingham, Alabama, during the 2012-2013 and 2013-2014 youth ice hockey seasons. Incidence rates (IRs) and incidence rate ratios (IRRs) of concussion were calculated for games/practices and age groups. A total of 23 369 (12 784 practice/10 585 game) athletic exposures (AEs) involving 37 medically diagnosed concussions occurred. More than 40% of concussions involved illegal contact. The combined IR for games and practices was 1.58 concussions per 1000 AEs. The IRR was 2.86 times (95% confidence interval 0.68-4.42) higher during games (2.49 per 1000 AEs) than practices (1.04 per 1000 AEs). The overall IR for concussion in youth ice hockey was comparable to those reported in other youth collision sports. The game-to-practice IRR was lower than previously reported in ice hockey and other youth sports, although more concussions per exposure occurred in games compared with practices. Younger players had a higher rate of concussions than older players. Copyright © 2016 by the American Academy of Pediatrics.
van der Does, Hendrike
Next to physical load and recovery as a result of training, psychosocial stress and recovery affect performance and injury risk of team sport players. This can be concluded based on a series of studies that focus on the relation between jumping technique, training load, training recovery,
te Wierike, Sanne C. M.; de Jong, Mark C.; Tromp, Eveline J. Y.; Vuijk, Pieter J.; Lemmink, Koen A. P. M.; Malina, Robert M.; Elferink-Gemser, Marije T.; Visscher, Chris
te Wierike, SCM, de Jong, MC, Tromp, EJY, Vuijk, PJ, Lemmink, KAPM, Malina, RM, Elferink-Gemser, MT, and Visscher, C. Development of repeated sprint ability in talented youth basketball players. J Strength Cond Res 28(4): 928-934, 2014-Factors affecting repeated sprint ability (RSA) were evaluated
Martínez, Héctor Pérez; Garbarino, Maurizio; Yannakakis, Georgios N.
This paper examines the generality of features extracted from heart rate (HR) and skin conductance (SC) signals as predictors of self-reported player affect expressed as pairwise preferences. Artificial neural networks are trained to accurately map physiological features to expressed affect in two...
Barrault, Servane; Bonnaire, Céline; Herrmann, Florian
Poker is a type of gambling that has specific features, including the need to regulate one's emotion to be successful. The aim of the present study is to assess emotion regulation, anxiety and depression in a sample of regular poker players, and to compare the results of problem and non-problem gamblers. 416 regular online poker players completed online questionnaires including sociodemographic data, measures of problem gambling (CPGI), anxiety and depression (HAD scale), and emotion regulation (ERQ). The CPGI was used to divide participants into four groups according to the intensity of their gambling practice (non-problem, low risk, moderate risk and problem gamblers). Anxiety and depression were significantly higher among severe-problem gamblers than among the other groups. Both significantly predicted problem gambling. On the other hand, there was no difference between groups in emotion regulation (cognitive reappraisal and expressive suppression), which was linked neither to problem gambling nor to anxiety and depression (except for cognitive reappraisal, which was significantly correlated to anxiety). Our results underline the links between anxiety, depression and problem gambling among poker players. If emotion regulation is involved in problem gambling among poker players, as strongly suggested by data from the literature, the emotion regulation strategies we assessed (cognitive reappraisal and expressive suppression) may not be those involved. Further studies are thus needed to investigate the involvement of other emotion regulation strategies.
Background: Physical education teachers often use the player-coach dyad in individual opposition sports so that students can obtain information on their actions and then better regulate them. This type of work also develops methodological and social skills. However, the task of observing a partner often poses problems for failing students, who…
van der Zwaag, Marjolein D.; Westerink, Joyce H.D.M.; van den Broek, Egon; Cohn, Jeffrey; Nijholt, Antinus; Pantic, Maja
This paper describes work toward an affective music player (AMP), which is able to direct affect to a goal state by selecting music. Repeatedly, music has been shown to modulate affect; however, precise guidelines for the use of music characteristics in an AMP have not been defined. To explore
Tamara Kramer, Barbara C.H. Huijgen, Marije T. Elferink-Gemser, Chris Visscher
Full Text Available Predicting current and future tennis performance can lead to improving the development of junior tennis players. The aim of this study is to investigate whether age, maturation, or physical fitness in junior elite tennis players in U13 can explain current and future tennis performance. The value of current tennis performance for future tennis performance is also investigated. A total of 86 junior elite tennis players (boys, n = 44; girls, n = 42 U13 (aged: 12.5 ± 0.3 years, and followed to U16, took part in this study. All players were top-30 ranked on the Dutch national ranking list at U13, and top-50 at U16. Age, maturation, and physical fitness, were measured at U13. A principal component analysis was used to extract four physical components from eight tests (medicine ball throwing overhead and reverse, ball throwing, SJ, CMJas, Sprint 5 and 10 meter, and the spider test. The possible relationship of age, maturation, and the physical components; “upper body power”, “lower body power”, “speed”, and “agility” with tennis performance at U13 and U16 was analyzed. Tennis performance was measured by using the ranking position on the Dutch national ranking list at U13 and U16. Regression analyses were conducted based on correlations between variables and tennis performance for boys and girls, separately. In boys U13, positive correlations were found between upper body power and tennis performance (R2 is 25%. In girls, positive correlations between maturation and lower body power with tennis performance were found at U13. Early maturing players were associated with a better tennis performance (R2 is 15%. In girls U16, only maturation correlated with tennis performance (R2 is 13%; later-maturing girls at U13 had better tennis performances at U16. Measuring junior elite tennis players at U13 is important for monitoring their development. These measurements did not predict future tennis performance of junior elite tennis players three
Massuça, Luís M; Fragoso, Isabel; Teles, Júlia
Researchers in the field of excellence in sport performance are becoming increasingly focused on the study of sport-specific characteristics and requirements. In accordance with this, the purposes of this study were (a) to examine the morphologic-, fitness-, handball-specific skills and psychological and "biosocial" differences between top elite and nontop elite team-handball players and (b) to investigate the extent to which they may be used to identify top elite team-handball players. One hundred sixty-seven adult male team-handball players were studied and divided in 2 groups: top elite (n = 41) and nontop elite (n = 126). Twenty-eight morphologic-, 9 fitness-, 1 handball-specific skills and 2 psychological-based and 2 "biosocial"-based attributes were used. Top elite and nontop elite groups were compared for each variable of interest using Student's t-test, and 5 logistic regression analyses were performed with the athlete's performance group (top elite or nontop elite) as the dependent variable and the variables of each category as predictors. The results showed that (a) body mass, waist girth, radiale-dactylion length, midstylion-dactylion length, and absolute muscle mass (morphologic model); (b) 30-m sprint time, countermovement jump height and average power, abdominal strength and the class of performance in the Yo-Yo Intermittent Endurance Test (fitness model); (c) offensive power (specific-skills model); (d) ego-based motivational orientation (psychological model); (e) socioeconomic status and the energy spent (for week) in handball activity (biosocial model); significantly (p handball player. Moreover, the fitness model exhibited higher percentages of correct classification (i.e., 91.5%) than all the other models did. This study provided (a) the rational to reduce the battery of tests for evaluation purposes, and (b) the initial step to work on building a multidisciplinary model to predict the probability of a handball athlete to be a top elite player.
Nower, Lia; Caler, Kyle R; Pickering, Dylan; Blaszczynski, Alex
Studies point to a relationship between fantasy sports/daily fantasy sports (DFS) play and gambling behavior. However, little is known about the nature of those relationships, particularly regarding the development of gambling problems. This study investigates the nature, frequency, and preferences of gambling behavior as well as problem gambling severity and comorbid conditions among DFS players. Data were collected from an epidemiologic survey of 3634 New Jersey residents on gambling and leisure activities. Participants were contacted by phone (land-line and cell) and online to obtain a representative, cross-sectional sample of non-institutionalized adults, aged 18 years or older. Excluding non-gamblers, the remaining 2146 participants, included in these analyses, indicated they had either played DFS (n = 299) or had gambled but not played DFS (1847) in the past year. Univariate comparisons and multiple logistic regression analyses were performed to identify the most significant characteristics and predictors of DFS players. Overall, a higher number of gambling activities, high frequency gambling, male gender, and reports of suicidal thoughts in the past year were most predictive of DFS players. Being Hispanic (vs. Caucasian) and/or single (vs. married or living with a partner) also doubled the odds of DFS play. Findings suggest that DFS players are characterized by high gambling frequency and problem severity and comorbid problems, notably suicidal ideation. Future research should examine the motivations and possible etiological sub-types of DFS players and the nature and course of DFS play, particularly in relation to gambling behavior and the development of gambling and other problems.
Full Text Available We investigated the level of dehydration after a match in 20 soccer players (mean ± SD, 17.9 ± 1.3 years old, height 1.75 ± 0.05 m, body mass 70.71± 7.65 kg from two teams that participate in a Brazilian Championship game performed at a temperature of 29 ± 1.1 C and a relative humidity of 64 ± 4.2%. Body mass, urine specific gravity and urinary protein were measured before and after the match, and self-perception measurements were performed during the match. Body mass loss was 1.00 ± 0.39 kg, corresponding to a dehydration percentage of 1.35 ± 0.87%. The mean sweating rate during the match was 866 ± 319 ml · h[sup]-1[/sup] and total fluid intake was 1265.00 ± 505.45 ml. The sweating rate and the quantity of ingested fluids correlated positively (r = 0.98; P<0.05. Protein occurred in the urine in 18 soccer players. The players showed no perception of thirst and considered themselves as comfortable during the match. At the end of the match the soccer players replaced 57.7 ± 15% of the water loss and presented a condition of significant to severe dehydration based on the post-match urine specific gravity data (1.027 ± 6 g · ml[sup]-1[/sup]. The results of this study demonstrate that most of the soccer players began the match with some degree of dehydration that worsened during the match.
Full Text Available Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET, until volitional fatigue. Outcome variables were exercise heart rate (HR, VO2, post-exercise blood lactate concentrations ([La]b and running speeds (km • h -2 . During the treadmill test, VO2max, maximal aerobic speed (MAS, HR and peak [La]b were 45.3±5.6 ml • kg-1 • min-1, 12.5±1.77 km • h -2 , 197±8 beats • min-1 and 11.3±1.4 mmol • l-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km • h -2 , 199±8 beats • min-1 and 2.5±2.2 mmol • l-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p<0.0001 with VO2max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players.
Leskošek, Bojan; Vodičar, Janez; Topič, Mojca Doupona
Abstract The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player’s success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player’s previous attitudes and/or behaviours (habitus), significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu’s theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players’ cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach’s alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1) had 2.2 times and the second factor (F8) had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better “success conditions” in the talent development of young players. PMID:28031770
Engel, David J; Schwartz, Allan; Homma, Shunichi
The incidence of sudden cardiac death is higher in US basketball players compared with other athlete groups. However, the recognition of the risk for sudden cardiac death among basketball players is challenging because little is known regarding athletic cardiac remodeling in these athletes or athletes of similarly increased size. To perform a comprehensive cardiac structural analysis of National Basketball Association (NBA) professional athletes. Echocardiographic observational study of NBA players on the active rosters for the 2013-2014 and 2014-2015 seasons was performed from December 16, 2013, to December 12, 2014. The policy of the NBA mandates annual preseason stress echocardiograms for each player. The NBA has sanctioned Columbia University Medical Center to conduct annual health and safety reviews of these echocardiograms. Data were analyzed from January to May 2015. Cardiac variables assessed included left ventricular (LV) size, mass, wall thickness, and hypertrophy patterns and function; left atrial volume; and aortic root diameter. All dimensions were biometrically scaled. Of the 526 athletes included in the study, 406 (77.2%) were African American and 107 (20.3%) were white, with a mean (SD) age of 25.7 (4.3) years. Mean (SD) athlete height was 200.2 (8.8) cm; mean body surface area, 2.38 (0.19) m2. Left ventricular size and mass in NBA athletes were proportional to body size, extending to the uppermost biometrics of the cohort. Left ventricular hypertrophy was present in 144 athletes (27.4%). African American athletes had increased LV wall thickness (unadjusted mean, 11.2 mm; 95% CI, 11.1-11.3 mm) and LV mass (unadjusted mean, 106.3 g/m2; 95% CI, 104.6-108.0 g/m2) compared with LV wall thickness (unadjusted mean, 10.5 mm; 95% CI, 10.3-10.7 mm; P basketball players and the athletic community at large.
Full Text Available The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player’s success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player’s previous attitudes and/or behaviours (habitus, significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu’s theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players’ cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach’s alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1 had 2.2 times and the second factor (F8 had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better “success conditions” in the talent development of young players.
Full Text Available Physical characteristics play an important role in the selection of young basketball players and the progress in their playing performance. The aim of the study was to analyze differences in chosen physical characteristics of Slovak U17 female basketball players with respect to their playing positions. We assumed, that there will be statistically significant differences between playing positions in each performance tests results. Chosen characteristics were analyzed for 14 players (mean/SD, age 16.34±0.82; body height 179.72±8.04 cm; body weight 67.62±7.10 kg; body fat 16.59±2.04 %; VO2max 46.20±4.71 ml.kg−1.min−1 according to their playing positions (guard, forward, center. Five specific performance tests for each player were conducted as a 3/4 Basketball court sprint, 10 × 5m Shuttle test, Lane agility drill, No-step vertical jump and Maximum vertical jump. The differences in tests results by playing positions were evaluated by one-way ANOVA. There were no significant differences found in results of chosen performance tests between playing positions (p>.05. In spite of fact, that there were no significant differences, we found interesting results between playing positions in physical characteristics. Guards had better results in speed (3.73±0.16 s, quickness (17.43±0.56 s and both lower-body power tests (47.16±3.06 cm; 57.00±3.40 cm than forwards and centers. Forwards had the best results in agility test (12.54±0.43 s. The results of this study produce useful information about physical characteristics of young basketball players according to their playing position and help to diagnose and improve their performance.
McGuine, Timothy A; Hetzel, Scott; McCrea, Michael; Brooks, M Alison
The incidence of sport-related concussion (SRC) in high school football is well documented. However, limited prospective data are available regarding how player characteristics and protective equipment affect the incidence of SRC. To determine whether the type of protective equipment (helmet and mouth guard) and player characteristics affect the incidence of SRC in high school football players. Cohort study; Level of evidence, 2. Certified athletic trainers (ATs) at each high school recorded the type of helmet worn (brand, model, purchase year, and recondition status) by each player as well as information regarding players' demographics, type of mouth guard used, and history of SRC. The ATs also recorded the incidence and days lost from participation for each SRC. Incidence of SRC was compared for various helmets, type of mouth guard, history of SRC, and player demographics. A total of 2081 players (grades 9-12) enrolled during the 2012 and/or 2013 football seasons (2287 player-seasons) and participated in 134,437 football (practice or competition) exposures. Of these players, 206 (9%) sustained a total of 211 SRCs (1.56/1000 exposures). There was no difference in the incidence of SRC (number of helmets, % SRC [95% CI]) for players wearing Riddell (1171, 9.1% [7.6%-11.0%]), Schutt (680, 8.7% [6.7%-11.1%]), or Xenith (436, 9.2% [6.7%-12.4%]) helmets. Helmet age and recondition status did not affect the incidence of SRC. The rate of SRC (hazard ratio [HR]) was higher in players who wore a custom mouth guard (HR = 1.69 [95% CI, 1.20-2.37], P football players. Players who had sustained an SRC within the previous 12 months were more likely to sustain an SRC than were players without a history of SRC. Sports medicine providers who work with high school football players need to realize that factors other than the type of protective equipment worn affect the risk of SRC in high school players. © 2014 The Author(s).
Full Text Available The analysis of positional data in association football allows the spatial distribution of players during matches to be described in order to improve the understanding of tactical-related constraints on the behavioural dynamics of players. The aim of this study was to identify how players' spatial restrictions affected the exploratory tactical behaviour and constrained the perceptual-motor workspace of players in possession of the ball, as well as inter-player passing interactions. Nineteen professional outfield male players were divided into two teams of 10 and 9 players, respectively. The game was played under three spatial constraints: a players were not allowed to move out of their allocated zones, except for the player in possession of the ball; b players were allowed to move to an adjacent zone, and; c non-specific spatial constraints. Positional data was captured using a 5 Hz interpolated GPS tracking system and used to define the configuration states of players for each second in time. The configuration state comprised 37 categories derived from tactical actions, distance from the nearest opponent, distance from the target and movement speed. Notational analysis of players in possession of the ball allowed the mean time of ball possession and the probabilities of passing the ball between players to be calculated. The results revealed that the players' long-term exploratory behaviour decreased and their short-term exploration increased when restricting their space of interaction. Relaxing players' positional constraints seemed to increase the speed of ball flow dynamics. Allowing players to move to an adjacent sub-area increased the probabilities of interaction with the full-back during play build-up. The instability of the coordinative state defined by being free from opponents when players had the ball possession was an invariant feature under all three task constraints. By allowing players to move to adjacent sub-areas, the
Rossing, N N; Nielsen, A B; Elbe, A-M; Karbing, D S
The primary purpose of this study was to investigate the effect of the place of early development in a sample of Danish male elite and youth handball and football players. The sample included 366 handball and football players from the elite Danish league in the season 2011-2012 and a comparison sample of youth players under the age of 12 from 2003, including 147,221 football and 26,290 handball players. Odds ratio analysis showed that both population size and density significantly affected the proportional number of youth players per community and the odds of athletes reaching an elite level in football and handball. The odds for youth player registrations in both handball and football increased in rural in contrast to urban communities. However, elite football players primarily came from communities of high density (>1000 pop./km(2)), whereas elite handball players primarily came from less densely populated communities (100 to <250 pop./km(2)). Furthermore, there seems to be a relation between representation of elite and talent clubs in different communities and the probability of becoming an elite player in both sports. The limited number of elite players in both sports from rural communities may be due to national talent development strategies that do not incorporate development support for clubs in rural areas. Additionally, the results of the study clearly suggest the need to include the youth player population to advance research findings in birthplace effect studies.
Full Text Available Current approaches regarding injury prevention focus on the transfer of evidence into daily practice. One promising approach is to influence attitudes and beliefs of players. The objective of this study was to record player's perceptions on injury prevention. A survey was performed among players of one German high-level football (soccer club. 139 professional and youth players between age 13 and 35 years completed a standardized questionnaire (response rate = 98%. It included categories with (1 history of lower extremity injuries, (2 perceptions regarding risk factors and (3 regularly used prevention strategies. The majority of players (84.2% had a previous injury. 47.5% of respondents believe that contact with other players is a risk factor, followed by fatigue (38.1% and environmental factors (25.9%. The relevance of previous injuries as a risk factor is differently perceived between injured (25% and uninjured players (0.0%. Nearly all players (91.5% perform stretching to prevent injuries, followed by neuromuscular warm up exercises (54.0%. Taping is used by 40.2% of previously injured players and 13.6% of players without a history of injuries. In conclusion, the perception of risk factors and performed preventive strategies are inconsistent with scientific evidence. Future transfer strategies should incorporate the players beliefs and attitudes.
Singh, S; Singh, M; Rathi, B
The purpose of the present study was to compare the kinanthropometric and performance characteristics of elite and non-elite female softball players. A total forty elite and non-elite level female softball players were selected from the different colleges affiliated to the Guru Nanak Dev University, Amritsar, for the present study. The height of subjects was measured by using the standard anthropometric rod. Weight was measured with portable weighing machine. Widths and diameters of body parts were measured by using digital caliper. Girths and lengths were taken with steel tape. Skinfold thickness measurements were taken using the Slimguide skinfold caliper. All subjects were also assessed for performance tests i.e. vertical jump, 50m sprint, medicine ball throw, 10×4m shuttle run and reaction time. Independent samples t-test reveals that elite female softball players were significantly taller (Psoftball players also had significantly greater biacromial (Psoftball players. The non-elite female softball players were found to have significantly greater thigh circumference (Psoftball players. The non-elite players were also found to have significantly higher percentage body fat (Psoftball players. The elite female softball players had significantly greater kinanthropometric characteristics, body composition and performance characteristics than the non-elite female softball players.
Yengo-Kahn, Aaron M; Zuckerman, Scott L; Stotts, Jeff; Zalneraitis, Brian H; Gardner, Ryan M; Kerr, Zachary Y; Solomon, Gary S
Basketball is a physical game played on a hardwood floor among high-jumping athletes at risk for injury. It is currently unknown how sport-related concussion (SRC) affects player performance after injury among professional basketball players. The objective of this study was to explore the impact of SRC on basketball performance among National Basketball Association (NBA) players. A retrospective, archival cohort study was performed that compared NBA player performance following concussion to pre-concussive performance. A comprehensive NBA injury database, compiled from publically available sources, was queried for NBA players who suffered concussion from 2005-06 to 2014-15 (10 seasons). Intra-and inter-player analyses were performed against a matched control group of players who missed playing time for personal reasons. Following application of inclusion/exclusion criteria and a matching process, 51 concussed players and 51 control players were included in analysis. There were no statistically significant decrements in baseline to post-concussion performance metrics in intra-player or player vs. controls after 5 return games. Our findings suggest that at the NBA level, an athlete's performance in the initial 5 games following injury does not suffer from the after-effects of concussive injury. These results may be useful in counseling professional athletes following a concussion.
Nicholas, Stephen J; Nicholas, James A; Nicholas, Calvin; Diecchio, Jennifer R; McHugh, Malachy P
Despite a perception that retired professional football players have poor health, there are little supporting data. Retired football players have poor health compared with age-matched population norms. Cross-sectional study; Level of evidence, 4. Thirty-six of 41 members of the 1969 Super Bowl winning team were contacted 35 years after that event (3 were deceased, and no contact information was available for 2). Players completed an SF-36 health survey and a medical history and football-specific questionnaire. Each player's football-related injury history before 1969 was documented from medical records. It was estimated that there was 80% power to detect a 10% difference in physical and mental health scores between the retired football players (age, 62 +/- 3 y) and population norms (n = 741) at an alpha level of 0.05. SF-36 scores for physical and mental health were not different from age-matched norms (physical health P = .69; mental health P = .49). The most prevalent medical conditions were arthritis (24 of 36 players), hypertension (13 of 36 players), and chronic low back pain (13 of 36 players). SF-36 physical health scores were 21% lower in players with arthritis (P football for 8.3 +/- 3.8 years, and 33 players (94%) reported having had "very fulfilling" (n = 24) or "somewhat fulfilling" (n = 9) careers. These professional football players had long and fulfilling careers with no apparent long-term detrimental effects on physical or mental health scores despite a high prevalence of arthritis.
Lund, Henrik Hautop; Friðriksson, Rafn Vídalín; Björnsson, Davíð Þór
In games where players are competing against each other, it can be of interest to ensure that all players are challenged according to their individual skills. In order to investigate such adaptivity to the individual player in physical multi-player games, we developed a game on modular interactive...... tiles which can be used in both single-player and multi-player mode. We implemented simple adaptivity methods and tested these with different user groups including children and adults of both genders. The results show statistically significant differences in the game interactions between children...... and adults, and between male and female players. Also, results show statistically significant differences in the game interactions between different physical set-ups of the modular interactive tiles, i.e. the interaction depended on the topology of the modular tiles set-up. Changing the physical set...
Milavić, Boris; Jurko, Damir; Grgantov, Zoran
With the aim of validating the Competitive State Anxiety Inventory on a population of young Croatian volleyball players, 286 examinees, 106 male and 180 female volleyball players (average age of 16.09+/-1.83), filled out the CSAI-2, constructed by Martens, Vealey, Burton, Bump and Smith (1990)1. Given the fact that all scales of the Competitive State Anxiety Inventory have good homogeneity, reliability and sensitivity, it can be concluded that they represent high-quality measuring instruments for measuring psychological characteristics of young volleyball players. Young male and female volleyball players generally have a moderate level of self-confidence, and their cognitive anxiety is more prominent that somatic anxiety. In order to determine the age and gender differences in somatic and cognitive anxiety and self-confidence, parametric analysis of differences was performed and coefficients of the independent samples t-test were calculated. By analysis of differences according to age, it has been established that female junior players, in relation to female youth players, express a significantly lower level of somatic and cognitive anxiety and a significantly higher level of self-confidence. As opposed to female players, male youth and junior players do not differ in any of the analysed variables. By analysis of differences according to gender, it has been established that male youth players have a significantly higher level of self-confidence in comparison to female youth players. No significant differences were found in the level of competitive anxiety and self-confidence by analysis of variance between different player roles. No significant differences were found by discriminant analysis in somatic and cognitive anxiety, and self-confidence of female volleyball players of different situational efficacy. The group of least efficient male volleyball players is characterized by a very low level of self-confidence, while the most efficient group of volleyball
Quarrie, Kenneth L; Raftery, Martin; Blackie, Josh; Cook, Christian J; Fuller, Colin W; Gabbett, Tim J; Gray, Andrew J; Gill, Nicholas; Hennessy, Liam; Kemp, Simon; Lambert, Mike; Nichol, Rob; Mellalieu, Stephen D; Piscione, Julien; Stadelmann, Jörg; Tucker, Ross
The loads to which professional rugby players are subjected has been identified as a concern by coaches, players and administrators. In November 2014, World Rugby commissioned an expert group to identify the physical demands and non-physical load issues associated with participation in professional rugby. To describe the current state of knowledge about the loads encountered by professional rugby players and the implications for their physical and mental health. The group defined 'load' as it relates to professional rugby players as the total stressors and demands applied to the players. In the 2013-2014 seasons, 40% of professional players appeared in 20 matches or more, and 5% of players appeared in 30 matches or more. Matches account for ∼5-11% of exposure to rugby-related activities (matches, team and individual training sessions) during professional competitions. The match injury rate is about 27 times higher than that in training. The working group surmised that players entering a new level of play, players with unresolved previous injuries, players who are relatively older and players who are subjected to rapid increases in load are probably at increased risk of injury. A mix of 'objective' and 'subjective' measures in conjunction with effective communication among team staff and between staff and players was held to be the best approach to monitoring and managing player loads. While comprehensive monitoring holds promise for individually addressing player loads, it brings with it ethical and legal responsibilities that rugby organisations need to address to ensure that players' personal information is adequately protected. Administrators, broadcasters, team owners, team staff and the players themselves have important roles in balancing the desire to have the 'best players' on the field with the ongoing health of players. In contrast, the coaching, fitness and medical staff exert significant control over the activities, duration and intensity of training
Li, Kaiming; Jiang, Jing; Qiu, Lihua; Yang, Xun; Huang, Xiaoqi; Lui, Su; Gong, Qiyong
Chess is a good model to study high-level human brain functions such as spatial cognition, memory, planning, learning and problem solving. Recent studies have demonstrated that non-invasive MRI techniques are valuable for researchers to investigate the underlying neural mechanism of playing chess. For professional chess players (e.g., chess grand masters and masters or GM/Ms), what are the structural and functional alterations due to long-term professional practice, and how these alterations relate to behavior, are largely veiled. Here, we report a multimodal MRI dataset from 29 professional Chinese chess players (most of whom are GM/Ms), and 29 age matched novices. We hope that this dataset will provide researchers with new materials to further explore high-level human brain functions.
Effect of quantum decoherence in a three-player quantum Kolkata restaurant problem is investigated using tripartite entangled qutrit states. Different qutrit channels such as, amplitude damping, depolarizing, phase damping, trit-phase flip and phase flip channels are considered to analyze the behaviour of players payoffs. It is seen that Alice's payoff is heavily influenced by the amplitude damping channel as compared to the depolarizing and flipping channels. However, for higher level of decoherence, Alice's payoff is strongly affected by depolarizing noise. Whereas the behaviour of phase damping channel is symmetrical around 50% decoherence. It is also seen that for maximum decoherence ( p = 1), the influence of amplitude damping channel dominates over depolarizing and flipping channels. Whereas, phase damping channel has no effect on the Alice's payoff. Therefore, the problem becomes noiseless at maximum decoherence in case of phase damping channel. Furthermore, the Nash equilibrium of the problem does not change under decoherence.
Procedural content generation for games --the automated creation of some type of asset-- has become increasingly popular in the last decade, both with academics and game developers. This interest has been mainly motivated by how complex games have become, requiring a huge amount of assets......, narrative events unfold in response to player input. Therefore, the music composer in an interactive environment needs to create music that is dynamic and non-repetitive. This thesis investigates how to express emotions and moods in music and how to apply this research to improve player experience in games....... This focus on the emotional expression that procedurally generated music should express has also been identified by Collins as one of the missing features that currently prevent procedurally generated music being more widely used in the game industry. The research therefore focuses on investigating...
Building on the definition of cinematography (Soanes and Stevenson, Oxford dictionary of English. Oxford University Press, Oxford/New York, 2005), game cinematography can be defined as the art of visualizing the content of a computer game. The relationship between game cinematography and its...... traditional counterpart is extremely tight as, in both cases, the aim of cinematography is to control the viewer’s perspective and affect his or her perception of the events represented. However, game events are not necessarily pre-scripted and player interaction has a major role on the quality of a game...... experience; therefore, the role of the camera and the challenges connected to it are different in game cinematography as the virtual camera has to both dynamically react to unexpected events to correctly convey the game story and take into consideration player actions and desires to support her interaction...
Miltersen, Peter Bro; Sørensen, Troels Bjerre
Koller, Megiddo and von Stengel showed how to efficiently compute minimax strategies for two-player extensive-form zero-sum games with imperfect information but perfect recall using linear programming and avoiding conversion to normal form. Koller and Pfeffer pointed out that the strategies...... obtained by the algorithm are not necessarily sequentially rational and that this deficiency is often problematic for the practical applications. We show how to remove this deficiency by modifying the linear programs constructed by Koller, Megiddo and von Stengel so that pairs of strategies forming...... a sequential equilibrium are computed. In particular, we show that a sequential equilibrium for a two-player zero-sum game with imperfect information but perfect recall can be found in polynomial time. In addition, the equilibrium we find is normal-form perfect. Our technique generalizes to general-sum games...
Miltersen, Peter Bro
Koller, Megiddo and von Stengel showed how to efficiently compute minimax strategies for two-player extensive-form zero-sum games with imperfect information but perfect recall using linear programming and avoiding conversion to normal form. Their algorithm has been used by AI researchers...... for constructing prescriptive strategies for concrete, often fairly large games. Koller and Pfeffer pointed out that the strategies obtained by the algorithm are not necessarily sequentially rational and that this deficiency is often problematic for the practical applications. We show how to remove this deficiency...... by modifying the linear programs constructed by Koller, Megiddo and von Stengel so that pairs of strategies forming a sequential equilibrium are computed. In particular, we show that a sequential equilibrium for a two-player zero-sum game with imperfect information but perfect recall can be found in polynomial...
Dye, M W G; Green, C S; Bavelier, D
Previous research suggests that action video game play improves attentional resources, allowing gamers to better allocate their attention across both space and time. In order to further characterize the plastic changes resulting from playing these video games, we administered the Attentional Network Test (ANT) to action game players and non-playing controls aged between 7 and 22 years. By employing a mixture of cues and flankers, the ANT provides measures of how well attention is allocated to targets as a function of alerting and orienting cues, and to what extent observers are able to filter out the influence of task irrelevant information flanking those targets. The data suggest that action video game players of all ages have enhanced attentional skills that allow them to make faster correct responses to targets, and leaves additional processing resources that spill over to process distractors flanking the targets.
Football is the most popular sport in the world, played by over 400 million men and women. In addition to the wide range of sport-specific technical and tactical skills needed, several physical components have been shown to be necessary to perform at a high level. The present PhD thesis is based...... on four articles that focus on physical testing and training for elite and sub-elite football players.The first article (Study I) aims to identify and establish aerobic capacities and anthropometric characteristics of elite female football players with the use of laboratory tests, and to examine whether...... systematic differences between the playing positions can be detected. Lately, field tests have become more frequently used in football than the laboratory tests used in Study I. Study II therefore aims to assess the validity of one of them, the Yo-Yo Intermittent Recovery test level 2 (Yo-Yo IR2). Along...
Wanming; LI; Huibo; SUN
Players of the agricultural industrial chain pursue their own profit maximization,which can lead to conflicts of interest and affect the stability of the industrial chain. Therefore,fair and reasonable profit allocation mechanism is the key to guaranteeing the development and strengthening the strategic alliance relationship between participate members. Shapley model is an effective method to solve the profit distribution in cooperative relations. But it does not consider the three factors: risks faced by players during the operation of the agricultural industrial chain,technology innovation ability,and the degree of participating in the cooperation. So,correction factors are introduced to modify the Shapley value model,in order to make the distribution of benefits more equitable and reasonable,and effectively guide practice.
Gwinup, G; Haw, T; Elias, A
Video games are one of the most popular recreational activities among Americans of all ages, especially teenaged boys and young men. Studies of the health hazards of video-game playing have linked seizures, psychologic disturbances, and other health problems with the games. The study reported here measured changes in blood pressure and heart rate that occurred in 23 young men when they played a video game. The mean systolic blood pressure for the entire group was considerably higher during play than before or after and was significantly higher in novice players than in more skilled players. Heart rate was also significantly higher during play. In view of these results, other cardiovascular changes might be expected to occur during video-game playing. Although the changes reported here were minor, even minor cardiovascular alterations could potentially prove serious in persons with cardiovascular disease.
Full Text Available Following the trends of IT use in education we propose four main principles of educational application development: anytime-anywhere access (including access for mobile devices; user-generated content; assigning users an active role inside the platform; creating a correlation between natural activities and educational activities – adding fun into the equation. With these principles in mind we developed a small Educational Player – a movie player that connects to a database to show information relevant to the events in the movie, more specific to the exact key-frame (in the movie time-line at the moment of the request. Though the application is still in a conceptual form, its possibilities make us confident in its future success either as an informal way of learning, or by using it in a formal educational context either as an e-learning tool, either as interactivity tool in a traditional classroom setting.
Santos, Gabriel; Pinto, Tiago; Vale, Zita
for the management of coalitions in electricity markets. This approach is tested using the multi-agent market simulator MASCEM (Multi-Agent Simulator of Competitive Electricity Markets), taking advantage of its ability to provide the means to model and simulate Virtual Power Players (VPP). VPPs are represented......Electricity Markets are not only a new reality but an evolving one as the involved players and rules change at a relatively high rate. Multi-agent simulation combined with Artificial Intelligence techniques may result in very helpful sophisticated tools. This paper presents a new methodology...... as coalitions of agents, with the capability of negotiating both in the market and internally, with their members in order to combine and manage their individual specific characteristics and goals, with the strategy and objectives of the VPP itself. A case study using real data from the Iberian Electricity...
Full Text Available The number of scientific investigations on women's football specific to the topics of player characteristics and demands of the game has considerably increased in recent years due to the increased popularity of the women's game worldwide, although they are not yet as numerous as in the case of men's football. To date, only two scientific publications have attempted to review the main findings of studies published in this area. However, one of them was published about 20 years ago, when women's football was still in its infancy and there were only a few studies to report on. The other review was more recent. Nonetheless, its main focus was on the game and training demands of senior elite female players. Thus, information on female footballers of lower competitive levels and younger age groups was not included. Consequently, an updated review is needed in this area. The present article therefore aims to provide an overview of a series of studies that have been published so far on the specific characteristics of female football players and the demands of match-play. Mean values reported in the literature for age (12–27 years, body height (155–174 cm, body mass (48–72 kg, percent body fat (13%–29%, maximal oxygen uptake (45.1–55.5 mL/kg/min, Yo-Yo Intermittent Recovery Test Level 1 (780–1379 m, maximum heart rate (189–202 bpm, 30 m sprint times (4.34–4.96 s, and counter-movement jump or vertical jump (28–50 cm vary mostly according to the players' competitive level and positional role. There are also some special considerations that coaches and other practitioners should be aware of when working with female athletes such as the menstrual cycle, potential pregnancy and lactation, common injury risks (particularly knee and head injuries and health concerns (e.g., female athlete triad, iron deficiency, and anemia that may affect players' football performance, health or return to play. Reported mean values for total distance
Odgaard, Peter Fogh; Stoustrup, Jakob; Vidal, Enrique Sanchez
Many have experienced the problem that their Compact Disc players have difficulties playing Compact Discs with surface faults like scratches and fingerprints. The cause of this is due to the two servo control loops used to keep the Optical Pick-up Unit focused and radially on the information track...... of the Compact Disc. The problem is to design servo controllers which are well suited for handling surface faults which disturb the position measurement and still react sufficiently against normal disturbances like mechanical shocks. In previous work of the same authors a feature based control scheme for CD......-players playing CDs with surface fault is derived and described. This feature based control scheme uses precomputed base to remove the surface fault influence from the position measurements. In this paper an adaptive version of the feature based control scheme is proposed and described. This adaptive scheme can...
Duncan, Michael J; Lyons, Mark; Nevill, Alan M
This study compared peak power estimated using 4 commonly used regression equations with actual peak power derived from force platform data in a group of adolescent basketball players. Twenty-five elite junior male basketball players (age, 16.5 +/- 0.5 years; mass, 74.2 +/- 11.8 kg; height, 181.8 +/- 8.1 cm) volunteered to participate in the study. Actual peak power was determined using a countermovement vertical jump on a force platform. Estimated peak power was determined using countermovement jump height and body mass. All 4 prediction equations were significantly related to actual peak power (all p jump prediction equations, 12% for the Canavan and Vescovi equation, and 6% for the Sayers countermovement jump equation. In all cases peak power was underestimated.
Matthew S Cain
Full Text Available Action video game players have demonstrated a number of attentional advantages over non-players. Here, we propose that many of those benefits might be underpinned by improved control over exogenous (i.e., stimulus-driven attention. To test this we used an anti-cuing task, in which a sudden-onset cue indicated that the target would likely appear in a separate location on the opposite side of the fixation point. When the time between the cue onset and the target onset was short (40 ms, non-players (nVGPs showed a typical exogenous attention effect. Their response times were faster to targets presented at the cued (but less probable location compared with the opposite (more probable location. Video game players (VGPs, however, were less likely to have their attention drawn to the location of the cue. When the onset asynchrony was long (600 ms, VGPs and nVGPs were equally able to endogenously shift their attention to the likely (opposite target location. In order to rule out processing-speed differences as an explanation for this result, we also tested VGPs and nVGPs on an attentional blink task. In a version of the attentional blink task that minimized demands on task switching and iconic memory, VGPs and nVGPs did not differ in second target identification performance (i.e., VGPs had the same magnitude of attentional blink as nVGPs, suggesting that the anti-cuing results were due to flexible control over exogenous attention rather than to more general speed-of-processing differences.
Hufschmidt, Jakob; Muehlmann, Marc; Tripodis, Yorghos; Stamm, Julie M.; Pasternak, Ofer; Giwerc, Michelle Y.; Coleman, Michael J.; Baugh, Christine M.; Fritts, Nathan G.; Heinen, Florian; Lin, Alexander; Stern, Robert A.; Shenton, Martha E.
Abstract Post-mortem studies reveal a high rate of cavum septi pellucidi (CSP) in chronic traumatic encephalopathy (CTE). It remains, however, to be determined whether or not the presence of CSP may be a potential in vivo imaging marker in populations at high risk to develop CTE. The aim of this study was to evaluate CSP in former professional American football players presenting with cognitive and behavioral symptoms compared with noncontact sports athletes. Seventy-two symptomatic former professional football players (mean age 54.53 years, standard deviation [SD] 7.97) as well as 14 former professional noncontact sports athletes (mean age 57.14 years, SD 7.35) underwent high-resolution structural 3T magnetic resonance imaging. Two raters independently evaluated the CSP, and interrater reliability was calculated. Within National Football League players, an association of CSP measures with cognitive and behavioral functioning was evaluated using a multivariate mixed effects model. The measurements of the two raters were highly correlated (CSP length: rho = 0.98; Intraclass Correlation Coefficient [ICC] 0.99; p football players compared with athlete controls. In addition, a greater length of CSP was associated with decreased performance on a list learning task (Neuropsychological Assessment Battery List A Immediate Recall, p = 0.04) and decreased test scores on a measure of estimate verbal intelligence (Wide Range Achievement Test Fourth Edition Reading Test, p = 0.02). Given the high prevalence of CSP in neuropathologically confirmed CTE in addition to the results of this study, CSP may serve as a potential early in vivo imaging marker to identify those at high risk for CTE. Future research is needed to investigate the pathomechanism underlying the development of CSP after repetitive head impacts, and its potential association with neuropathologically confirmed CTE. PMID:26414478
Vidal, Enrique Sanchez; Hansen, K.G.; Andersen, R.S.
The design of the positioning controllers in Optical Disk Drives are today subjected to a trade off between an acceptable suppression of external disturbances and an acceptable immunity against surfaces defects. In this paper an algorithm is suggested to detect defects of the disk surface combined...... with an observer and a Linear Quadratic Regulator. As a result, the mentioned trade off is minimized and the playability of the tested compact disk player is considerably enhanced....
Full Text Available Many sports (for instance soccer are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training. It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes’ emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak. As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was
This thesis deals with online computer games and their influence on the lifestyle of players. The work is divided into 2 parts ─ theoretical and research. The theoretical part describes the basic information about the history of computer games and the Internet, the distribution of computer games, addictive behavior on the Internet and computer games as well as problems that can cause excessive use of computers. In the research part, I tried to find answers to research questions. The aim of th...
van der Zwaag, Marjolein D.; Westerink, Joyce H.D.M.; van den Broek, Egon; Cohn, Jeffrey; Nijholt, Antinus; Pantic, Maja
This paper describes work toward an affective music player (AMP), which is able to direct affect to a goal state by selecting music. Repeatedly, music has been shown to modulate affect; however, precise guidelines for the use of music characteristics in an AMP have not been defined. To explore these, we investigated the influence of music characteristics on 32 participants who listened to 16 songs, testing effects of tempo (slow/high), mode (minor/major), and percussiveness (low/high). Subjec...
Full Text Available The aim of this study was to determine the effect of caffeine intake on overall basketball performance in experienced players. A double-blind, placebo-controlled, randomized experimental design was used for this investigation. In two different sessions separated by one week, 20 experienced basketball players ingested 3 mg of caffeine/kg of body mass or a placebo. After 60 min, participants performed 10 repetitions of the following sequence: Abalakov jump, Change-of-Direction and Acceleration Test (CODAT and two free throws. Later, heart rate, body impacts and game statistics were recorded during a 20-min simulated basketball game. In comparison to the placebo, the ingestion of caffeine increased mean jump height (37.3 ± 6.8 vs. 38.2 ± 7.4 cm; p = 0.012, but did not change mean time in the CODAT test or accuracy in free throws. During the simulated game, caffeine increased the number of body impacts (396 ± 43 vs. 410 ± 41 impacts/min; p < 0.001 without modifying mean or peak heart rate. Caffeine also increased the performance index rating (7.2 ± 8.6 vs. 10.6 ± 7.1; p = 0.037 during the game. Nevertheless, players showed a higher prevalence of insomnia (19.0 vs. 54.4%; p = 0.041 after the game. Three mg of caffeine per kg of body mass could be an effective ergogenic substance to increase physical performance and overall success in experienced basketball players.
James Newman; Daniel Ashton
Videogame walkthroughs provide instructions on various elements of gameplay in relation to specific digital games, and exist as text-based documents and, to a lesser extent, as recorded moving image game footage. We focus here on written-walkthroughs for the purposes of depth, while recognising the specific and significant position that moving image walkthroughs hold (see Ashton, forthcoming). Player-produced walkthroughs, freely and widely distributed online, point to the broader social cont...
Bavelier, D; Achtman, RL; Mani, M; Föcker, J
Over the past few years, the very act of playing action video games has been shown to enhance several different aspects of visual selective attention. Yet little is known about the neural mechanisms that mediate such attentional benefits. A review of the aspects of attention enhanced in action game players suggests there are changes in the mechanisms that control attention allocation and its efficiency (Hubert-Wallander et al., 2010). The present study used brain imaging to test this hypothes...
Brooks, Brian L.; Mannix, Rebekah; Maxwell, Bruce; Zafonte, Ross; Berkner, Paul D.; Iverson, Grant L.
Background There is increasing concern about the possible long-term effects of multiple concussions, particularly on the developing adolescent brain. Whether the effect of multiple concussions is detectable in high school football players has not been well studied, although the public health implications are great in this population. Purpose To determine if there are measureable differences in cognitive functioning or symptom reporting in high school football players with a history of multiple concussions. Study Design Cross-sectional study; Level of evidence, 3. Methods Participants included 5232 male adolescent football players (mean [±SD] age, 15.5 ± 1.2 years) who completed baseline testing between 2009 and 2014. On the basis of injury history, athletes were grouped into 0 (n = 4183), 1 (n = 733), 2 (n = 216), 3 (n = 67), or ≥4 (n = 33) prior concussions. Cognitive functioning was measured by the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery, and symptom ratings were obtained from the Post-Concussion Symptom Scale. Results There were no statistically significant differences between groups (based on the number of reported concussions) regarding cognitive functioning. Athletes with ≥3 prior concussions reported more symptoms than did athletes with 0 or 1 prior injury. In multivariate analyses, concussion history was independently related to symptom reporting but less so than developmental problems (eg, attention or learning problems) or other health problems (eg, past treatment for psychiatric problems, headaches, or migraines). Conclusion In the largest study to date, high school football players with multiple past concussions performed the same on cognitive testing as those with no prior concussions. Concussion history was one of several factors that were independently related to symptom reporting. PMID:27474382
Thorborg, Kristian; Serner, Andreas; Petersen, Jesper
An ipsilateral hip adduction/abduction strength ratio of more than 90%, and hip adduction strength equal to that of the contralateral side have been suggested to clinically represent adequate strength recovery of hip adduction strength in athletes after groin injury. However, to what extent side-......-to-side symmetry in isometric hip adduction and abduction strength can be assumed in soccer players remains uncertain....
Crichton, James; Jones, Doug R; Funk, Lennard
Background Shoulder injuries in rugby players are common, but the mechanisms of injury are less well understood. This study aims to elucidate common mechanisms of injury and identify the patterns of injury they produce. Materials and methods Twenty-four elite rugby players, referred to the senior author for diagnosis and management of shoulder injuries, were selected. Videos of the injuries were independently reviewed by rugby-medical experts to describe the mechanisms of injury. The mechanisms reported were collated and analysed to determine the level of agreement between reviewers and conclude an overall description of injury mechanisms. Results The authors identified three mechanisms of shoulder injury from the video analysis. These are the ‘Try-Scorer’, characterised by hyperflexion of the outstretched arm such as when scoring a try; the ‘Tackler’, extension of the abducted arm behind the player while tackling; and the ‘Direct Impact’, a direct blow to the arm or shoulder when held by the side in neutral or slight adduction. The Try Scorer and Tackler mechanisms both involve a levering force on the glenohumeral joint (GHJ). These mechanisms predominantly cause GHJ dislocation, with Bankart, reverse Bankart and superior labrum anterior–posterior tears. The Try-Scorer Mechanism also caused the majority (83%) of rotator cuff tears. The Direct Hit mechanism resulted in GHJ dislocation and labral injury in 37.5% of players and was most likely to cause acromioclavicular joint dislocation and scapula fractures, injuries that were not seen with the other mechanisms. Conclusion Greater understanding of the mechanisms involved in rugby shoulder injury is useful in understanding the pathological injuries, guiding treatment and rehabilitation and aiding the development of injury-prevention methods. PMID:22510645
Kawasaki, Takayuki; Maki, Nobukazu; Shimizu, Kyoko; Ota, Chihiro; Urayama, Shingo; Moriya, Shuichi; Kaketa, Takefumi; Kobayashi, Hideo; Kaneko, Kazuo
Scapular dyskinesis is observed in subjects with pathologic conditions of the shoulder; however, there is limited information about the factors related to scapular dyskinesis among participants in rugby. The purpose of this study was to investigate the incidence, reliability, and relationships between scapular dyskinesis and variables related to the shoulder in high-school rugby players. A total of 164 Japanese high-school rugby players were evaluated with questionnaires, physical examinations, and a video analysis during their preseason. After evaluation of the inter-rater reliability of a classification of scapular dyskinesis, the outcomes were analyzed to assess the relationships between scapular dyskinesis and other variables during the preseason. The data were assessed with a logistic regression analysis calculating the odds ratios (OR). The inter-rater reliability among 3 blinded observers based on the Fleiss κ value and percentage agreement was .52 and 79.0%, respectively, which indicates that the method is moderately reliable. Scapular dyskinesis was identified in 16 (10.1%) shoulders among 159 players, with type I being prominent. A multivariate logistic regression analysis revealed that a type I dyskinesis was significantly associated with a past history of stingers with projected pain to the affected side of the shoulder (OR, 3.7) and the player's competitive grade at the time of the survey (OR, 3.9). Scapular dyskinesis is significantly associated with a past history of stingers. This suggests that stingers are a causative factor of scapular dyskinesis in the rugby population. Our method of evaluating scapular dyskinesis in collision athletes exhibits moderate reliability. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
Romberg, Kerstin; Tufvesson, Ellen; Bjermer, Leif
Background: Elite athletes, independent of sport, have increased risk of developing asthma, but little is known about sex difference among adolescent athletes. Objective: To investigate and compare sex-related differences according to symptoms and treatment of asthma, allergy, and health among elite athletes and a reference group. Methods: Adolescent elite swimmers (n = 101), tennis players (n = 86), and a reference group (n = 1,628) responded to a questionnaire about respiratory symptoms, al...
Zago, Matteo; Piovan, Andrea Gianluca; Annoni, Isabella; Ciprandi, Daniela; Iaia, F Marcello; Sforza, Chiarella
Dribbling speed in soccer is considered critical to the outcome of the game and can assist in the talent identification process. However, little is known about the biomechanics of this skill. By means of a motion capture system, we aimed to quantitatively investigate the determinants of effective dribbling skill in a group of 10 Under-13 sub-elite players, divided by the median-split technique according to their dribbling test time (faster and slower groups). Foot-ball contacts cadence, centre of mass (CoM), ranges of motion (RoM), velocity and acceleration, as well as stride length, cadence and variability were computed. Hip and knee joint RoMs were also considered. Faster players, as compared to slower players, showed a 30% higher foot-ball cadence (3.0 ± 0.1 vs. 2.3 ± 0.2 contacts · s(-1), P < 0.01); reduced CoM mediolateral (0.91 ± 0.05 vs. 1.14 ± 0.16 m, P < 0.05) and vertical (0.19 ± 0.01 vs. 0.25 ± 0.03 m, P < 0.05) RoMs; higher right stride cadence (+20%, P < 0.05) with lower variability (P < 0.05); reduced hip and knee flexion RoMs (P < 0.05). In conclusion, faster players are able to run with the ball through a shorter path in a more economical way. To effectively develop dribbling skill, coaches are encouraged to design specific practices where high stride frequency and narrow run trajectories are required.
Raizel, Raquel; da Mata Godois, Allan; Coqueiro, Audrey Yule; Voltarelli, Fabrício Azevedo; Fett, Carlos Alexandre; Tirapegui, Julio; de Paula Ravagnani, Fabricio Cesar; de Faria Coelho-Ravagnani, Christianne
Despite the well-documented importance of nutrition in optimizing performance and health, the dietary intake of soccer players has attracted little attention. We aimed to assess the pre-season dietary intake of professional soccer players and its adequacy in macro and micronutrients. The pre-season dietary intake of 19 male athletes was assessed using a semi-structured 3-day food record. To determine dietary adequacy and excess, energy and macronutrient intake were compared with the Brazilian dietary reference values for athletes, and micronutrients were compared with the Estimated Average Requirement - EAR (minimum recommendation) and Tolerable Upper Intake Level - UL (maximum recommendation). Mean daily energy intake (40.74±12.81 kcal/kg) was adequate. However, there was a low carbohydrate intake (5.44±1.86 g/kg/day) and a high amount of protein and fat (1.91±0.75 and 1.27±0.50 g/kg/day, respectively). Sodium intake (3141.77±939.76 mg/day) was higher than UL (2300 mg/day), while the majority of players showed daily intake of vitamin A (74%), vitamin D (100%), folate (58%), calcium and magnesium (68%) below the EAR (625, 10 and 320 µg/day, 800 and 330 mg/day, respectively). The dietary intake of professional soccer players was adequate in energy, but inadequate in macro and micronutrients, which suggests the need to improve nutritional practices to sustain the physical demands of soccer during pre-season.
Lehman, Everett J
The purpose of this article is to review the history of head injuries in relation to American-style football play, summarize recent research that has linked football head injuries to neurodegeneration, and provide a discussion of the next steps for refining the examination of neurodegeneration in football players. For most of the history of football, the focus of media reports and scientific studies on football-related head injuries was on the acute or short-term effects of serious, traumatic...
Gardner, Raquel C.; Hess, Christopher P.; Brus-Ramer, Marcel; Possin, Katherine L.; Cohn-Sheehy, Brendan I.; Kramer, Joel H.; Berger, Mitchel S.; Yaffe, Kristine; Miller, Bruce; Rabinovici, Gil D.
Previous studies report that cavum septum pellucidum (CSP) is frequent among athletes with a history of repeated traumatic brain injury (TBI), such as boxers. Few studies of CSP in athletes, however, have assessed detailed features of the septum pellucidum in a case-control fashion. This is important because prevalence of CSP in the general population varies widely (2% to 85%) between studies. Further, rates of CSP among American pro-football players have not been described previously. We sou...
Fornaciari, Diego; Callens, Stefaan
Competition rules maximise consumer welfare by promoting efficient use of scarce resource and thus high output, low prices, high quality, varied services, innovation, production and distribution. European courts consider doctors and hospital staff as undertakings (any entity that performs economic activities), so that if they enter into agreements then they have to comply with competition rules. This paper's objective is to determine whether competition law, which applies to undertakings, can in fact be applied to different healthcare-sector players and whether specific rules are needed regarding competition between healthcare undertakings. Data were selected from relevant European and national case law, European institution legal documents (such as regulations, guidelines and communications) and healthcare competition law literature, and then examined. The paper finds that competition rules are applicable to healthcare players considering the consequences if competition rules are applied to the healthcare market. For market processes to result in the appropriate cost, quality and output, competition law must be proactive. In other words, quality must be fully factored into the competitive mix, allowing consumers to weigh healthcare price and non-price characteristics. Countries have different healthcare system and competition rules (although similar), competition rule impact is different for each country. Some healthcare systems are more regulated and there will be less opportunity for healthcare players to compete. Efficiently applying competition law to healthcare players means that several challenges need facing, such as healthcare quality complexity and court scepticism. This article points out the challenges when competition law is applied to the healthcare sector and how these challenges are faced in certain countries such as The Netherlands.
Full Text Available The primary objective of the present study was to evaluate the agreement between the dominant leg (DL (determined subjectively and the stronger leg (SL (determined via a functional test in a group of basketball and volleyball players. The secondary objective was to calculate lower limb neuromuscular asymmetry when comparing the DL vs the non-dominant leg (NDL and the SL vs the weaker (WL leg in the whole group and when differentiating by sex. Seventy-nine male and female volleyball and basketball players (age: 23.7 ± 4.5 years performed three single-leg vertical countermovement jumps (SLVCJ on a contact mat. Vertical jump height and an inter-limb asymmetry index (ASI were determined. Only 32 (40% of the subjects had a concordance between the perception of their dominant leg and the limb reaching the highest jump height. Using the DL as the discriminating variable, significant (p<0.05 inter-limb differences were found in the total group of players. When comparing between sexes, significant differences (p<0.05 arose in the female group only. With regard to the WL vs. the SL, significant (p<0.05 differences were noted in the whole group and when stratified into males and females. The mean ASI ranged from 9.31% (males to 12.84% (females and from 10.49% (males to 14.26% (females, when comparing the DL vs. the NDL and the SL vs. the WL, respectively. Subjective expression of leg dominance cannot be used as a predictor of limb jump performance. Vertical jump asymmetry of 10-15% exists and this can be considered as a reference value for male and female basketball and volleyball players.
Full Text Available Physical activity improves various metabolic disturbances. The effect of physical activity on non-alcoholic fatty liver disease (NAFLD has not been defined, particularly in athletes who are able to consume a diet to increase body mass. The aim of this study was to evaluate the prevalence of NAFLD and associated factors of NAFLD among male university rugby football players [n = 69, 37 forwards (FW and 32 backs (BK], relative to age-matched controls (CON; n = 29. For FW players exercise consists of physical contact play, such as ruck, mall, scrum, and tackle. For BK players exercise consists of sprints and endurance running. Liver function tests and bioimpedance analysis to assess body composition were performed. Subjects consuming ≤ 20 g/day of ethanol and exhibiting an aspartate transaminase (AST level ≥ 33 U/L, and/or alanine transaminase (ALT level ≥ 43 U/L, were considered to have NAFLD. The PNPLA3 and MTP genotypes were determined using real-time polymerase chain reaction (PCR. The body mass index, body fat mass, and lean body mass were significantly higher in the FW group than in the BK and CON groups (P < 0.05. The total cholesterol, low-density lipoprotein cholesterol, triglyceride, AST, ALT, and alkaline phosphatase levels were significantly higher in the FW group than in the CON group (P < 0.05. The prevalence of NAFLD was significantly higher in the FW group than in the BK group and CON group (18.9, 8.6, and 0.0%, respectively, whereas there were non-significant between-group differences in the frequency of the PNPLA3 and MTP genotypes. These findings indicate that rugby football players, especially those in the FW position, are at higher risk of developing NAFLD, which emphasizes the role of diet and exercise in the development of NAFLD.
Rutkowska, Katarzyna; Bergier, Józef
Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training). It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes' emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska) and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak). As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was average or low
Gardner, Andrew J; Iverson, Grant L; Wojtowicz, Magdalena; Levi, Christopher R; Kay-Lambkin, Frances; Schofield, Peter W; Zafonte, Ross; Shultz, Sandy R; Lin, Alexander P; Stanwell, Peter
The aim of this study was to examine brain neurometabolite concentrations in retired rugby league players who had a history of numerous self-reported concussions. Participants were 16 retired professional rugby league players (ages 30-45 years) with an extensive history of concussion and participation in contact sports, and 16 age- and education-matched controls who had no history of neurotrauma or participation in contact sports. All completed a clinical interview, psychological and cognitive testing, and magnetic resonance spectroscopy (MRS) investigation. MRS voxels were placed in posterior cingulate grey matter and parietal white matter. Neurometabolite concentrations were quantified using LCModel. It was hypothesized that retired athletes would differ on N-acetyl aspartate, myo-inositol, choline, glutamate, and glutathione. Retired players had significantly lower concentrations of grey matter glutathione (p=0.02, d=0.91). They did not significantly differ in concentrations of other neurometabolites. There were no significant differences between groups on measures of depression, anxiety, or cognitive functioning. The retired athletes reported significantly greater alcohol use (pcognitive performance and self-reported psychological functioning. © Georg Thieme Verlag KG Stuttgart · New York.
Full Text Available Optimizing bone mass gain during childhood and adolescence may help prevent bone diseases in advanced ages. The aim of this study was to verify the bone mineral density (BMD and bone mineral content (BMC in female adolescent’s handball players. This is a cross-sectional study where 68 female adolescents (12–17 years were allocated into two groups: handball players (n = 29 (HG and control group (n = 39 (CG. BMC and BMD from total body (TB, total body less head (TBLH, lumbar spine (L1–L4, femoral neck (FN, Ward’s triangle (WT and respectively Z-scores were measured using dual-energy X-ray absorptiometry (DXA. Sexual maturity, menarche, PHV, time of sun exposure, physical activity level and Calcium and vitamin D intake were assessed. The HG showed significantly higher BMC, BMD as well Z-scores values (p≤0.05 of total body, TBLH, femoral neck, hip and lumbar spine than the CG. When the values were adjusted for lean soft tissue (LST the HG showed significantly higher BMC of femoral neck (p≤0.05, as well as BMD of TBLH and femoral neck (p≤0.05 and Z-score values all bone sites except hip, than the CG. We conclude that handball players have significantly higher bone mass values compared to group of girls of the same age.
Carson, Fraser; Polman, Remco C J
The aim of the present study was to explore the views of professional rugby union players during the early rehabilitation, late rehabilitation and return to play stages, following anterior cruciate ligament (ACL) injury. A qualitative dominant, mixed methodological approach was utilized with five players who had suffered an ACL injury requiring reconstructive surgery. A longitudinal approach, concurrent with each player's rehabilitation, consisting of twice monthly interviews, a self-report diary and three established questionnaires (MOS-Social Support Survey, Sherbourne & Stewart, 1991; Sport Climate Questionnaire, Deci & Ryan, n.d.; Injury Rehabilitation Questionnaire, Deci & Ryan, n.d.) were completed. Theoretical thematic analysis was conducted on three distinct phases (Early Limited Participation phase, 10 higher order themes; Late Limited Rehabilitation phase, 11 higher order themes; and Return to Play phase, 9 higher order themes) and coded relating to autonomy, competence and relatedness. The findings suggest that increased autonomy and control assist emotional and behavioral responses during rehabilitation and return to play, while development of competence increases self-confidence.
Hudson, Christy; Garrison, J Craig; Pollard, Kalyssa
The Lower Quarter Y Balance (YBT-LQ) Test performance varies depending on competitive level, sport, gender, and age; therefore, determining normative scores specific to a population may be helpful in identifying injury-risk thresholds and return-to-play criteria following an injury. The purpose of this study was to determine normative YBT-LQ scores by assessing a subset of female, Division I volleyball players. A descriptive analysis cohort study. Ninety healthy (19.6 ± 1.2 y/o), collegiate female volleyball players. YBT-LQ was measured in 3 distinct directions of anterior (ANT), posteromedial (PM) and posterolateral (PL) on both the dominant and non-dominant limbs. In addition, a one way ANOVA was performed to determine mean group differences of YBT-LQ dominant and non-dominant limb composite score across position. Baseline values for this population were 94.1 ± 6.6% on the dominant limb and 93.9 ± 6.2% on the non-dominant limb. There were no significant differences for YBT-LQ composite scores on dominant (P = 0.867) and non-dominant (P = 0.989) limbs between position. This study identified normative YBT-LQ composite scores for healthy, female, collegiate volleyball players. Participants performed similarly despite their position. Copyright Â© 2016 Elsevier Ltd. All rights reserved.
Molik, Bartosz; Morgulec-Adamowicz, Natalia; Marszałek, Jolanta; Kosmol, Andrzej; Rutkowska, Izabela; Jakubicka, Alicja; Kaliszewska, Ewelina; Kozłowski, Robert; Kurowska, Monika; Ploch, Elwira; Mustafins, Pavel; Gómez, Miguel-Ángel
The aims of the current study were (a) to analyze the differences in game performances of sitting volleyball athletes representing the different types of disabilities and (b) to assess whether the seated position vertical reach is one of the crucial factors in the game performance level of sitting volleyball athletes. One hundred male athletes from various national teams participating in the European Championships in Sitting Volleyball (2009) took part in this study. The athletes were categorized according to type of disability and the results of the vertical reach in a seated position. Thirtysix games were analyzed using the Game Performance Sheet for Sitting Volleyball. Twenty-three game performance parameters were studied. In addition, the sum and effectiveness of attacks, blocks, block services, services, ball receiving, and defensive actions were calculated. The main results indicated significant differences between athletes with minimal disability and athletes with single amputations from above the knee in the level of defensive performances and the summation of defensive actions. There was also a significant difference between athletes in relation to their vertical reach during activity and attacking actions, blocks, and ball receiving. In addition, there were strong relationships between the players' vertical reach scores and their activity and effectiveness in sitting volleyball. In conclusion, the accuracy of the World Organization Volleyball for Disabled classification systems for sitting volleyball players was confirmed. There is a strong relationship between players' vertical reach and their effectiveness in sitting volleyball.
Background In overhead sports like volleyball, the onset of a rotator cuff tendinopathy due to functional overload is a common observation. An angiofibroblastic etiopathogenesis has been hypothesized, whereby a greater anaerobic metabolism occurs in critical zones of the tendon with a lower degree of vascularization; this would induce collagen and extracellular matrix degradation, that could then trigger a compensatory neovascularization response. We performed a clinical observational study of 80 elite volleyball players, monitoring the perfusion values of the supraspinatus tendons by oximetry. Results No statistically significant differences were found between the oximetry data and age, sex or years of sports activity, nor when comparing the right and left arm or the dominant and non-dominant arm. A statistically significant difference was found for the dominant arm values in relation to the competitive role, higher values being obtained in outside hitters (62.7%) than middle hitters (53.7%) (p = 0.01), opposite hitters (55.5%) (p = 0.02) and libero players (54.4%) (p = 0.008), whereas there were no differences in setters (56.2%) (p > 0.05). Conclusions The different tendon vascularization values found in players with different roles in the team may be attributed to a response to the specific biomechanical demands posed by the different overhead throwing roles. PMID:22853746
Melchiorri, G; Padua, E; Padulo, J; D'Ottavio, S; Campagna, S; Bonifazi, M
Fifty-three members of the Italian Men Water Polo Team were filmed using two synchronized cameras, while they were shooting a goal. Considering the differences in body mass, height, training strategies and the technical-tactical features of the players, the aims of this study were to employ video-analysis techniques in order to investigate selected kinematic parameters in water polo throwing, and to provide comprehensive quantitative information on the throwing movement in relation to the different team player positions. Video analysis was used to estimate the elbow angle at release, the shoulder angle at follow through, the back and head height at ball release, trunk rotation angle and ball velocity at release. Ball release velocities ranged from 21.0 to 29.8 m/s (average value 25.3±1.4 m/s), for field players. Goal keepers show the lowest team values (average 21.7±0.3 m/s). Similar to previous study results, ball release was typically reached just prior to the elbow approaching full extension (151.6±3.6°), and the follow through shoulder angle was 143±5.9°. No significant statistical difference was recorded between injured and non-injured athletes. No positive association was demonstrated between physical characteristics (body mass and height) and ball velocity.
Full Text Available Digital games have been frequently used to illustrate the new organisational frameworks that are based on persuading users to carry out tasks and assignments not traditionally associated with them. However coined, ‘user-innovation’ (von Hippel, 2005, ‘crowdsourcing’ (Howe, 2008 or ‘pro-am revolution’ (Leadbeater and Miller, 2004, contemporary examples of this phenomena always include digital games. A closer look at the recent open innovation manifestos reveals that the oft-cited examples come almost entirely from PC games while console games remain mostly non-existent in these texts. It is clear that PC and console games differ both in use and in the cultures they create (Taylor, 2007. Equally, the technological and economic backgrounds of the market sectors have their differences (Kerr, 2006.The concept of LittleBigPlanet, a console game inherently dependent on player production, challenges the neat binary of some much cited arguments about tethered appliances. The first set of research questions rises from this observation. What are the technical and economic constraints and affordances the console as a platform uses to position the productive activities of players? How do these differ from the forms of player production typical of PC gaming (see Sotamaa, 2007a; and Sotamaa, 2007b?
Full Text Available The present study investigated changes in indirect markers of muscle damage following a simulated tennis match play using nationally ranked young (17.6 ± 1.4 years male tennis players. Ten young athletes played a 3-hour simulated match play on outdoor red clay courts following the International Tennis Federation rules. Muscle soreness, plasma creatine kinase activity (CK, serum myoglobin concentration (Mb, one repetition maximum (1RM squat strength, and squat jump (SJ and counter movement jump (CMJ heights were assessed before, immediately after, and 24 and 48 h after the simulated match play. All parameters were also evaluated in a non-exercised group (control group. A small increase in the indirect markers of muscle damage (muscle soreness, CK and Mb was detected at 24-48 hours post-match (p<0.05. A marked acute decrement in neuromuscular performance (1RM squat strength: -35.2 ± 10.4%, SJ: -7.0 ± 6.0%, CMJ: -10.0 ± 6.3% was observed immediately post-match (p<0.05. At 24 h post-match, the 1RM strength and jump heights were not significantly different from the baseline values. However, several players showed a decrease of these measures at 24 h after the match play. The simulated tennis match play induced mild muscle damage in young players. Coaches could monitor changes in the indirect markers of muscle damage to assess athletes’ recovery status during training and competition.
In a context of growing dependence on extra-European sources, a growth potential in gas use for power generation and the acceleration of the liberalization process, the 2008 Edition of 'The Players on the European Gas Market' offers a unique detailed review of the positioning of players in both the upstream (production, reserves) and downstream (wholesale and retail supply) sectors of the gas chain. This 140-pages report, includes 55 tables and 29 figures, and presents an in-depth description of the European gas industry by country. The Survey 'The Players on the European Gas Market' provides: - The analysis of new upstream areas and production growth prospects, - Company rankings in terms of reserve and production volumes, - The complete overview of the whole European gas market (market characteristics, supply sources, consuming outlets, effective competition), - Strategies and key facts of the wholesale suppliers to Europe, - An in-depth review of national market structures, - The detailed positioning and analysis of national market power of the numerous companies involved in gas supply
Kerr, Zachary Y; Marshall, Stephen W; Guskiewicz, Kevin M
The reliability of athletes to recall and self-report a concussion history has never been quantified. This study examined the reliability of the self-report concussion history measure and explored determinants of recall in the number of self-reported concussions in a group of retired professional football players. In 2001, a short questionnaire was administered to a cohort of former professional football players to ascertain the number of self-reported concussions they sustained during their professional playing careers. In 2010, the same instrument was readministered to a subset (n = 899) of the original cohort to assess reliability. Overall reliability was moderate (weighted Cohen κ = 0.48). The majority (62.1%) reported the same number of concussions in both administrations (2001 and 2010); 31.4% reported more concussions in the second administration. Compared with the "same number reported" group, the "greater number reported" group had more deficits in the second administration in their Short Form 36 physical health (composite score combining physical functioning, role physical, bodily pain, general health) and mental health (e.g., composite score combining vitality, social functioning, role emotional) scales. The self-reported concussion history had moderate reliability in former professional football players, on the basis of two administrations of the same instrument, 9 yr apart. However, changes in health status may be differentially associated with recall of concussions.
Pinto, Tiago; Vale, Zita; Sousa, Tiago
Energy systems worldwide are complex and challenging environments. Multi-agent based simulation platforms are increasing at a high rate, as they show to be a good option to study many issues related to these systems, as well as the involved players at act in this domain. In this scope the authors......, the type of day (business day, weekend, holiday, etc.) and most important, the renewable based distributed generation forecast. The proposed approach is tested and validated using real electricity markets data from the Iberian operator – MIBEL.......’ research group has developed a multi-agent system: MASCEM (Multi- Agent System for Competitive Electricity Markets), which performs realistic simulations of the electricity markets. MASCEM is integrated with ALBidS (Adaptive Learning Strategic Bidding System) that works as a decision support system...... for market players. The ALBidS system allows MASCEM market negotiating players to take the best possible advantages from each market context. However, it is still necessary to adequately optimize the players’ portfolio investment. For this purpose, this paper proposes a market portfolio optimization method...
Leslie Andrews Portes
Full Text Available The objective of this study was to determine anthropometric and physical fitnesscharacteristics of Brazilian male children and adolescents at the beginning of soccer training. Inthis study, 282 male soccer players ranging in age from 10 to 13 years were evaluated. The athletesparticipated in a formal soccer training program 3 times per week, with each training lasting 3hours. Anthropometric and physical fitness parameters were obtained. The boys were divided intoage classes and prevalence data were analyzed using Pearson’s chi-square test. Parametric datawere compared by one-way ANOVA or the Kruskal-Wallis test, when necessary. The resultsare expressed as the mean ± standard deviation and a p value <0.05 was considered to be significant.Growth, development, body adiposity and physical fitness characteristics were adequateand proportional to age among the boys studied (p<0.05. It was concluded that anthropometricand physical fitness characteristics of young male elite soccer players improve with and areproportional to age. Children and adolescents greatly benefit from regular physical activity. Thepresent results show that young male soccer players present adequate anthropometric conditionsand physical fitness prior to the initiation of formal training at soccer clubs.
Puente, Carlos; Areces, Francisco
The aim of this study was to determine the effect of caffeine intake on overall basketball performance in experienced players. A double-blind, placebo-controlled, randomized experimental design was used for this investigation. In two different sessions separated by one week, 20 experienced basketball players ingested 3 mg of caffeine/kg of body mass or a placebo. After 60 min, participants performed 10 repetitions of the following sequence: Abalakov jump, Change-of-Direction and Acceleration Test (CODAT) and two free throws. Later, heart rate, body impacts and game statistics were recorded during a 20-min simulated basketball game. In comparison to the placebo, the ingestion of caffeine increased mean jump height (37.3 ± 6.8 vs. 38.2 ± 7.4 cm; p = 0.012), but did not change mean time in the CODAT test or accuracy in free throws. During the simulated game, caffeine increased the number of body impacts (396 ± 43 vs. 410 ± 41 impacts/min; p basketball players. PMID:28925969
Alvarez-Díaz, Pedro; Alentorn-Geli, Eduard; Steinbacher, Gilbert; Rius, Marta; Pellisé, Ferran; Cugat, Ramón
The purpose of this study was to report the functional outcomes of young active soccer players with lumbar spondylolysis undergoing conservative treatment. Between 2002 and 2004, all soccer players diagnosed with spondylolysis with a minimum 2-year follow-up were retrospectively reviewed. All patients were treated nonoperatively with cessation of sports activity and rehabilitation for 3 months. The rehabilitation protocol was identical for all patients and emphasized strengthening of abdominal muscles, stretching of the hamstrings, "core" stability exercises, and trunk rotational movements in a pain-free basis. Those patients with pain at rest and with daily life activities were also treated with a thoracolumbar orthosis. Symptomatic patients or those with positive SPECT were not allowed to return to sports and continued the rehabilitation protocol for 3 more months. The mean time of cessation of sports activity was 3.9 months (SD 0.8) and 5.2 months (SD 2.1) for a complete return to sports. At the 2-year follow-up, 28 patients (82%) obtained excellent results, 4 (12%) good results, 1 patient (3%) a fair result, and 1 patient (3%) a poor result. Conservative treatment of spondylolysis in young soccer players with cessation of sports and rehabilitation, with or without thoracolumbar orthosis, was associated with excellent functional results in terms of return to sports and level of achievable physical activity.
Full Text Available Background: Basketball, as an exciting team sport, is very popular among athletes with disabilities. Among psychological skills, mood states as an important variable have been of special interest to researchers. Objectives: The purpose of the present study was to investigate and compare profile of mood states (BRUMS of disabled former soldiers who play basketball in different age groups. Methodology: After getting permit to conduct the research, 28 disabled basketball players completed the demographic survey and the Brunel Mood Scale (BRUMS questionnaire. BRUMS consisted of 24 items in subscales of stress, anger, depression, fatigue, confusion and vigor. The one-way analysis of variance test was used for the data analysis. The significance level was set at P≤0.05. SPSS Statistics 22.0 was used for the analysis of data. Results: The results showed that mood states become less negative with age. However, scores showed a rising trend in the 35-39 age groups (mood of anger with P=0/02 fatigue with P=0/03 and confusion with P=0/04. Conclusion: It seems that examining the psychological variables in relation to age can help develop more effective strategies in physical and mental training programs for disabled players. Keywords: Mood States, Basketball Players, veteran with disabilities, Age
Zerguini, Yacine; Ahmed, Qanta A; Dvorak, Jiri
Islam is a monotheistic Abrahamic faith characterised by devotional orthopraxy. The actions expected of followers of Islam are closely prescribed in the Qur'an. Muslims understand Ramadan as a mandatory requirement, excused only in the event of illness, infirmity or extremes of age. Due to the increasing popularity of football among Muslims, more and more Muslim football players of all levels make the decision to follow the Ramadan fast while they need to practise and compete. Sports medicine clinicians and scientists have the responsibility to provide them with the knowledge and evidence on how exactly Ramadan fasting impacts on their performance and how to optimise their eating, drinking and sleeping in order to minimise negative effects of their religious practice, should any have been demonstrated. The first International Federation of Football Associations (FIFA) Medical Assessment and Research Centre (F-MARC) study concluded that biochemical, nutritional, subjective well-being and performance variables were not adversely affected in young male national level players who followed Ramadan fasting in a controlled environment. Match performance was however not measured and the study did not include elite level players, leading to the Ramadan consensus meeting in order to answer the remaining questions. The conclusions and recommendations published in this supplement suggest that the best coping strategies will remain individual - as is the choice to fast.
Fort-Vanmeerhaeghe, Azahara; Gual, Gabriel; Romero-Rodriguez, Daniel; Unnitha, Viswanath
The primary objective of the present study was to evaluate the agreement between the dominant leg (DL) (determined subjectively) and the stronger leg (SL) (determined via a functional test) in a group of basketball and volleyball players. The secondary objective was to calculate lower limb neuromuscular asymmetry when comparing the DL vs the non-dominant leg (NDL) and the SL vs the weaker (WL) leg in the whole group and when differentiating by sex. Seventy-nine male and female volleyball and basketball players (age: 23.7 ± 4.5 years) performed three single-leg vertical countermovement jumps (SLVCJ) on a contact mat. Vertical jump height and an inter-limb asymmetry index (ASI) were determined. Only 32 (40%) of the subjects had a concordance between the perception of their dominant leg and the limb reaching the highest jump height. Using the DL as the discriminating variable, significant (pjump performance. Vertical jump asymmetry of 10-15% exists and this can be considered as a reference value for male and female basketball and volleyball players.
Full Text Available The iterated prisoner’s dilemma (IPD is well known within the domain of game theory. Although it is relatively simple, it can also elucidate important problems related to cooperation and trust. Generally, players can predict their opponents’ actions when they are able to build a precise model of their behavior based on their game playing experience. However, it is difficult to make such predictions based on a limited number of games. The creation of a precise model requires the use of not only an appropriate learning algorithm and framework but also a good dataset. Active learning approaches have recently been introduced to machine learning communities. The approach can usually produce informative datasets with relatively little effort. Therefore, we have proposed an active modeling technique to predict the behavior of IPD players. The proposed method can model the opponent player’s behavior while taking advantage of interactive game environments. This experiment used twelve representative types of players as opponents, and an observer used an active modeling algorithm to model these opponents. This observer actively collected data and modeled the opponent’s behavior online. Most of our data showed that the observer was able to build, through direct actions, a more accurate model of an opponent’s behavior than when the data were collected through random actions.
Verleysen, Cédric; De Vleeschouwer, Christophe
This paper builds on a prior work for player detection, and proposes an efficient and effective method to distinguish among players based on the numbers printed on their jerseys. To extract the numbers, the dominant colors of the jersey are learnt during an initial phase and used to speed up the segmentation of the candidate digit regions. An additional set of criteria, considering the relative position and size (compared to the player bounding box) and the density (compared to the digit rectangular support) of the digit, are used to filter out the regions that obviously do not correspond to a digit. Once the plausible digit regions have been extracted, their recognition is based on feature-based classification. A number of original features are proposed to increase the robustness against digit appearance changes, resulting from the font thickness variability and from the deformations of the jersey during the game. Finally, the efficiency and the effectiveness of the proposed method are demonstrated on a real-life basketball dataset. It shows that the proposed segmentation runs about ten times faster than the mean-shift algorithm, but also outlines that the proposed additional features significantly increase the digit recognition accuracy. Despite significant deformations, 40% of the samples, that can be visually recognized as digits, are well classified as numbers. Out of these classified samples, more than 80% of them are correctly recognized. Besides, more than 95% of the samples, that are not numbers, are correctly identified as non-numbers.
Jacob, Alvin; Zakaria, Wan Nurshazwani Wan; Tomari, Mohd Razali Bin Md; Sek, Tee Kian; Suberi, Anis Azwani Muhd
This paper focuses on the development of a wearable sensor system to identify the different types of badminton grip that is used by a player during training. Badminton movements and strokes are fast and dynamic, where most of the involved movement are difficult to identify with the naked eye. Also, the usage of high processing optometric motion capture system is expensive and causes computational burden. Therefore, this paper suggests the development of a sensorized glove using flex sensor to measure a badminton player's finger flexion angle. The proposed Hand Monitoring Module (HMM) is connected to a personal computer through Bluetooth to enable wireless data transmission. The usability and feasibility of the HMM to identify different grip types were examined through a series of experiments, where the system exhibited 70% detection ability for the five different grip type. The outcome plays a major role in training players to use the proper grips for a badminton stroke to achieve a more powerful and accurate stroke execution.
Razali, Nazim; Mustapha, Aida; Yatim, Faiz Ahmad; Aziz, Ruhaya Ab
This paper is set to introduce a new framework from the perspective of Computer Science for identifying talents in the sport of football based on the players’ individual qualities; physical, mental, and technical. The combination of qualities as assessed by coaches are then used to predict the players’ position in a match that suits the player the best in a particular team formation. Evaluation of the proposed framework is two-fold; quantitatively via classification experiments to predict player position, and qualitatively via a Talent Identification Site developed to achieve the same goal. Results from the classification experiments using Bayesian Networks, Decision Trees, and K-Nearest Neighbor have shown an average of 98% accuracy, which will promote consistency in decision-making though elimination of personal bias in team selection. The positive reviews on the Football Identification Site based on user acceptance evaluation also indicates that the framework is sufficient to serve as the basis of developing an intelligent team management system in different sports, whereby growth and performance of sport players can be monitored and identified.
Csapo, Peter; Avugos, Simcha; Raab, Markus; Bar-Eli, Michael
Previous research has shown that changes in shot difficulty may have rendered the hot-hand effect in basketball unobservable and are potentially a result of defensive adjustments. However, it has not been directly analysed whether strategic changes indeed take place in response to streakiness and whether they are effective with respect to winning games. The current work consists of an experimental study with 18 professional coaches and 20 players based on video sequences from National Basketball Association games, where the shown player displayed a streaky performance in half of the sequences. While coaches were asked to devise a defensive strategy after each viewed sequence, players had to assume the role of the shown player and decide whether to shoot or pass the ball. We find that coaches tended to increase the defensive pressure significantly more often on presumably hot players and thus make use of the hot-hand heuristic. Meanwhile, players chose to shoot more frequently in low-pressure and streaky situations but selected "pass" regardless of the previous performance when they faced increased defensive pressure. Assuming that a streaky player's performance is indeed elevated during hot phases, hot-hand behaviour can be considered adaptive in certain situations as it led hot players to pass instead of shoot.
Full Text Available Massively multiplayer online role-playing games (MMORPGs have great potential as sites for research within the social and human-computer interaction. In the MMORPGs, a stability player taxonomy model is very important for game design. It helps to balance different types of players and improve business strategy of the game. The players in mobile MMORPGs are also connected with social networks; many studies only use the player's own attributes statistics or questionnaire survey method to predict player taxonomy, so lots of social network relations' information will be lost. In this paper, by analyzing the impacts of player's social network, commercial operating data from mobile MMORPGs is used to establish our player taxonomy model (SN model. From the model results, social network-related information in mobile MMORPGs will be considered as important factors to pose this optimized player taxonomy model. As experimental results showed, compared with another player taxonomy model (RA model, our proposed player taxonomy model can achieve good results: classification is more stable.
Full Text Available Aim: The aim of this study was to determine whether the characteristics of goal orientation and perceived motivational climate change according to the playing positions of amateur footballers. Material and Methods: Four hundred and sixty amateur male football players participated in the study (age, 21.72±4.63 years; football experience, 9.24±4.18 years. Footballers were named as the defence (n=199, midfield (n=187 and forward (n=74 according to their playing position. The scores of perceived motivational climate and goal orientation were determined by the Turkish versions of ‘The Task and Ego Orientation in Sport Questionnaire’ and ‘The Perceived Motivation Climate Questionnaire’, which were adopted by Toros (2002. Results: Pearson correlation analyses showed that football experience had no effect on task orientation, ego orientation, mastery climate, and performance climate. ANOVA and post-hoc Tukey tests showed that task orientation and mastery climate scores were higher in defence players than midfield players (p=0.003 vs. p<0.001. Ego orientation and performance climate scores of the midfield and defence players differed in favour of the midfield players (p<0.001 vs. p<0.001. Although there were no statistically significant differences in terms of the scores of task orientation and ego orientation among forward, defence, and midfield players, performance climate scores were higher in forward players than midfield players (p<0.001. Conclusion: According to the results of this study, players who have higher task orientation and mastery climate scores can play as defence players, and other players who have higher ego orientation and performance climate scores can play as midfield players. With the need for more extensive studies to determine the goal orientation and motivational climate scores of forward players, scores that are obtained from questionnaires should be evaluated with physical and physiological tests.
Haugen, Thomas A; Tønnessen, Espen; Seiler, Stephen
The purpose of this investigation was to compare sprint and countermovement-jump (CMJ) performance among female competitive soccer players as a function of performance level, field position, and age. In addition, the authors wanted to quantify the evolution of these physical characteristics among elite players over a 15-y period. 194 female elite players (22± 4.1 y, 63 ± 5.6 kg), including an Olympic winning squad, tested 40-m sprint with electronic timing and CMJ on a force platform at the Norwegian Olympic training center from 1995 to 2010. Moderate to large velocity differences across performance levels and positions were observed. National-team players were 2% faster than 1st-division players (P = .027, d = 0.5) and 5% faster than 2nd-division players (P players jumped 8-9% higher than 1st-division players (P = .001, d = 0.6) and junior elite players (P = .023, d = 0.5). Forwards were 3-4% faster than midfielders (P Players from 2006-2010 were 2% faster (P players from 1995-1999 over 20 m, whereas no differences in 20- to 40-m velocity or CMJ performance were observed. This study provides effect-magnitude estimates for the influence of performance level, age, and player position on sprint and CMJ performance in female soccer players. While 20- to 40-m velocity and CMJ performance have remained stable over the time, there has been a moderate but positive development in 0- to 20-m velocity among elite performers.
Amin, Nirav H; Old, Andrew B; Tabb, Loni P; Garg, Rohit; Toossi, Nader; Cerynik, Douglas L
A complete rupture of the Achilles tendon is a devastating injury. Variables affecting return to competition and performance changes for National Basketball Association (NBA) players are not readily evident. Players in the NBA who ruptured their Achilles tendons and who underwent surgical repair would have more experience in the league, and the performance of those who were able to return to competition would be decreased when compared with their performance before injury and with their control-matched peers. Cohort study; Level of evidence, 3. Data for 18 basketball players with Achilles tendon repair over a 23-year period (1988-2011) were obtained from injury reports, press releases, and player profiles. Variables included age, body mass index (BMI), player position, and number of years playing in the league. Individual season statistics were obtained, and the NBA player efficiency rating (PER) was calculated for 2 seasons before and after injury. Controls were matched by playing position, number of seasons played, and performance statistics. Univariate and multivariate analyses were performed to assess the effect of each factor. At the time of injury, the average age was 29.7 years, average BMI was 25.6, and average playing experience was 7.6 years. Seven players never returned to play an NBA game, whereas 11 players returned to play 1 season, with 8 of those players returning for ≥2 seasons. Players who returned missed an average of 55.9 games. The PER was reduced by 4.57 (P = .003) in the first season and by 4.38 (P = .010) in the second season. When compared with controls, players demonstrated a significant decline in the PER the first season (P = .038) and second season (P = .081) after their return. The NBA players who returned to play after repair of complete Achilles tendon ruptures showed a significant decrease in playing time and performance. Thirty-nine percent of players never returned to play.
Sindik, Josko; Missoni, Sasa
The purpose of this study is to adapt imported instruments for measuring multidimensional perfectionism in sport situations and perceived group cohesion, in terms of construct validity and reliability, as well as from the aspect of interpretability, addressed on Croatian samples of athletes. Group Environment Questionnaire (GEQ) and Sport Multidimensional Perfectionism Scale (MSSP) are applied. The sample of 223 male Croatian athletes comprises of N1 = 107 top basketball players from nine teams in A-1 Croatian Basketball League and N2 = 116 recreational table tennis players who play in Table Tennis Organization of Clubs and Actives in Zagreb. Principal Components Analyses at both instruments showed two-component structures: combined social-task cohesion and friendship were latent dimensions of perceived group cohesion, while the internalized standards and externalized standards revealed two aspects of multidimensional perfectionism in sport situations. In perceived group cohesion, basketball players achieved higher average results than table tennis players in the friendship, while the table tennis players showed higher combined social and task orientation than basketball players. In multidimensional sport perfectionism, basketball players have higher average result than table tennis players in the dimension of internalized perfectionism, but in externalized perfectionism there is no statistical significant difference. Younger players showed higher average results than older players in the dimension of friendship, while older players showed higher combined social and task orientation than younger players. Younger players have higher average scores in internalized perfectionism. The main importance of the research is adjustment of multidimensional perfectionism in sport situations and perceived group cohesion to Croatian athletes, providing additional possibility of cross-cultural adjustment of both concepts, psychometrically and theoretically.
Full Text Available The expansion of basketball game, just like up-to-date sports results represent the stimulus for further fundamental researches in the aim of improvement scientific and methodological basis of a training work and all other factors connected to the improvement of a training process and top sports creativity. The research was conducted with the aim to determine the specifics of motor abilities in basketball players of the junior rank of competition. All the examinees were male, 16 (+/-6 months years old, 132 in total, all of them were basketball players of the basketball club ”Student” from Nis. The batery of tests for the evaluation of motor abilities included tests for the evaluation of coordination, strength (explosive, repetitive and static, flexibility and stamina and it consisted of 13 motor tests in total. The gained results were processed by the program system for multivariant analysis of data, especially made by Popovic D. for personal computers. The gained results are shown in tables and they give insight into the structure of latent dimensions of basketball players. The motor structure of basketball players is explained by 72.3% of common variance. From the matrix of intercorrelations, four main components were gained. The fist defines tests of static strength, flexibility and repetitive strength; the second is saturated by the test for the evaluation of explosive strength, balance and two tests for the evaluation of repetitive strength. The third is the best explained by the test for the evaluation of balance, flexibility and coordination. The fourth main component is defined by explosive strength. Then, the rotation of components into the oblimin solution is conducted and some better structure of latent dimensions is gained that way. In basketball and other popular sports games in our country, scientific and expert methods and possibilities of scientific fundation of the trainig work are very slowly but surely accepted.The trend
Tambe, Amol; Badge, Ravi; Funk, Lennard
Rugby is an increasingly popular collision sport. A wide spectrum of injuries can be sustained during training and match play. Rotator cuff injury is uncommon in contact sports and there is little published literature on the treatment of rotator cuff tears in rugby players. We therefore reviewed the results and functional outcomes of arthroscopic rotator cuff repair in elite rugby players. Eleven professional rugby players underwent arthroscopic rotator cuff repair at our hospital over a 2-year period. We collected data on these patients from the operative records. The patients were recalled for outcome scoring and ultrasound scans. There were seven rugby league players and four rugby union players, including six internationals. Their mean age was 25.7 years. All had had a traumatic episode during match play and could not return to the game after the injury. The mean time to surgery was 5 weeks. The mean width of the cuff tear was 1.8 cm. All were full- thickness cuff tears. Associated injuries included two Bankart lesions, one bony Bankart lesion, one posterior labral tear, and two 360 degrees labral tears. The biceps was involved in three cases. Two were debrided and a tenodesis was performed in one. Repair was with suture anchors. Following surgery, all patients underwent a supervised accelerated rehabilitation programme. The final follow-up was at 18 months (range: 6-31 months) post surgery. The Constant scores improved from 44 preoperatively to 99 at the last follow-up. The mean score at 3 months was 95. The Oxford shoulder score improved from 34 to 12, with the mean third month score being 18. The mean time taken to return to full match play at the preinjury level was 4.8 months. There were no complications in any of the patients and postoperative scans in nine patients confirmed that the repairs had healed. We conclude that full-thickness rotator cuff tears in the contact athlete can be addressed successfully by arthroscopic repair, with a rapid return to
Malina, Robert M; Figueiredo, António J; Coelho-E-Silva, Manuel J
Studies of the body size and proportions of athletes have a long history. Comparisons of athletes within specific sports across time, though not extensive, indicate both positive and negative trends. To evaluate secular variation in heights and weights of male youth soccer players reported in studies between 1978 and 2015. Reported mean ages, heights, and weights of male soccer players 9-18 years of age were extracted from the literature and grouped into two intervals: 1978-99 and 2000-15. A third-order polynomial was fitted to the mean heights and weights across the age range for each interval, while the Preece-Baines model 1 was fitted to the grand means of mean heights and mean weights within each chronological year to estimate ages at peak height velocity and peak weight velocity for each time interval. Third-order polynomials applied to all data points and estimates based on the Preece-Baines model applied to grand means for each age group provided similar fits. Both indicated secular changes in body size between the two intervals. Secular increases in height and weight between 1978-99 and 2000-15 were especially apparent between 13 and 16 years of age, but estimated ages at peak height velocity (13.01 and 12.91 years) and peak weight velocity (13.86 and 13.77 years) did not differ between the time intervals. Although the body size of youth soccer players increased between 1978-99 and 2000-15, estimated ages at peak height velocity and peak weight velocity did not change. The increase in height and weight likely reflected improved health and nutritional conditions, in addition to the selectivity of soccer reflected in systematic selection and retention of players advanced in maturity status, and exclusion of late maturing players beginning at about 12-13 years of age. Enhanced training programs aimed at the development of strength and power are probably an additional factor contributing to secular increases in body weight.
Avhandling (doktorgrad) - Norges idrettshøgskole, 2015 Background: High performance in soccer depends on various physical qualities and skills, including tactical and technical skills as the two most import factors that contribute to success. These skills could be more important than small differences in physical performance abilities. Nevertheless, to be able to utilize the tactical and technical skills during a top soccer match, a soccer player has to cope with the physical demands...
Ghuman, D; Griffiths, MD
One key limitation with the contemporary online gaming research literature is that much of the published research has tended to examine only one genre of games (i.e., Massively Multiplayer Online Role Playing Games). Three relatively little studied online games are First Person Shooter (FPS) Games, Role Play Games (RPG) and Real Time Strategy (RTS) Games. Therefore, the current study aimed to examine player behaviour and characteristics in these three different online gaming genres. More spec...
Jakobsen, Mette; Christensen, Daniel Svejstrup; Bruni, Luis Emilio
In game narrative the central role of the protagonist becomes a challenge as the protagonist often conflates with the player character, which the author and the player share control over. This paper investigates whether knowledge of the player character’s alignment, i.e. the inner thoughts...... of the character, can influence how they decide to progress in a game. The player character’s alignment will present an internal conflict, which will sometimes conflict with the external goal of a game. It is investigated whether players are more likely to abandon their external goal, and ultimately change...... their in-game behaviour, when exposed to the internal conflict of their character. A test was conducted in which participants played through one of two similar versions of the same game; one in which they were exposed to the player character’s internal conflict, and another in which they were not. The test...
Full Text Available The National Football League (NFL has recently received significant negative media attention surrounding the safety of its players, revolving largely around the long term health risks of playing the sport. Recent premature deaths and instances of suicide associated with chronic traumatic encephalopathy and other football related injuries have brought the sport under increased scrutiny. By comparing mortality rates of the general population to mortality rates of players using publically available data from the 1970 and 1994 NFL seasons, we test whether participation in football is significantly harmful to the longevity of the players. We conclude that, in total, players in the NFL have lower mortality rates than the general population. However, there is evidence that line players have higher mortality rates than other players and that those who played more games have higher mortality rates than those who played fewer games.
Mohr, Magni; Krustrup, Peter; Andersson, Helena
, (2) fatigue develops temporarily during and towards the end of a game, and (3) defenders have lower work rates than midfielders and attackers. The difference in high-intensity running between the 2 levels demonstrates the importance of intense intermittent exercise for match performance in women......We sought to study the physical demands and match performance of women soccer players. Nineteen top-class and 15 high-level players were individually videotaped in competitive matches, and time-motion analysis were performed. The players changed locomotor activity >1,300 times in a game...... fewer (P women soccer players (1) top-class international players perform more intervals of high-intensity running than elite players at a lower level...
Burelli, Paolo; Triantafyllidis, George; Patras, Ioannis
In this paper, we investigate on the relationship between player experience and body movements in a non-physical 3D computer game. During an experiment, the participants played a series of short game sessions and rated their experience while their body movements were tracked using a depth camera....... The data collected was analysed and a neural network was trained to find the mapping between player body movements, player in- game behaviour and player experience. The results reveal that some aspects of player experience, such as anxiety or challenge, can be detected with high accuracy (up to 81......%). Moreover, taking into account the playing context, the accuracy can be raised up to 86%. Following such a multi-modal approach, it is possible to estimate the player experience in a non-invasive fashion during the game and, based on this information, the game content could be adapted accordingly....
Full Text Available Presents the results of the study the basic aspects of self-confidence of young players. The study involved 54 young chess players. Of these, 34 students Kherson CYSS Chess. 20 players from different regions of Ukraine. Age investigated from 10 to 15 years. The dependence of the confidence of participation in competitions for young players on the level of anxiety, motivational set, strong-willed self-control. In the result of performance of young chess players in the competition is directly proportional to the strength of motivation to succeed installation. Most athletes have been observed high levels of self-willed. Self-control depends on the experience of participation of young players in the competition, as well as facilities manager.
Madsen, Christian Møller; Badault, Benjamin; Nybo, Lars
Badminton-specific speed and endurance performance was evaluated in both cross-sectional and longitudinal studies of elite youth players and compared to the physiological capacities of world top-50 singles players.The cross-sectional study involved ten males in the category U15 (..., nine U19 and four senior elite players. They performed 30-m sprint, counter-movement jump (CMJ) and badminton-specific speed (B-SPEED) and endurance (B-ENDURANCE) tests. The longitudinal data were collected for ten U15 players with 1- and 2-year follow-up measures.Compared to seniors, B...... with ageing from 29±5 % deficit for U15 to 13±6 % deficit for U19 (Pbadminton-specific speed improves markedly with ageing in youth elite players to achieve, by age 19, values matching world-class players. Endurance improved markedly, but with a significant deficit remaining...
Schokkaert, Jeroen; De Luca, Giacomo; Swinnen, Jo
We examine the impact of a different cultural background on individual behavior, focusing on the aggressiveness level of southern and nothern European football players in the English Premier League. We find that southern European football players collect on average more yellow and red cards as compared to their nothern European colleagues. We also find that the initially more aggressive football violent behavior displayed by southern European players coverges towards the local average, the lo...
De Luca, Giacomo; Schokkaert, Jeroen; Swinnen, Johan F. M.
We examine the impact of a different cultural background on individual behavior, focusing on violence on the football field of southern European and nothern European football players in the English Premier League. We find that southern European football players collect on average more football penalties than their nothern European colleagues. We also find that the initially higher number of football penalties incurred by southern European players converges towards the local average, the longe...
Smeddinck, Jan D.; Gerling, Kathrin M.; Tiemkeo, Saranat
Motion-based video games can have a variety of benefits for the players and are increasingly applied in physical therapy, rehabilitation and prevention for older adults. However, little is known about how this audience experiences playing such games, how the player experience affects the way older adults interact with motion-based games, and how this can relate to therapy goals. In our work, we decompose the player experience of older adults engaging with motion-based games, focusing on the e...
Gallo, Tania F; Cormack, Stuart J; Gabbett, Tim J; Lorenzen, Christian H
The impact of perceived wellness on a range of external load parameters, rating of perceived exertion (RPE) and external load:RPE ratios, was explored during skill-based training in Australian footballers. Fifteen training sessions involving 36 participants were analysed. Each morning before any physical training, players completed a customised perceived wellness questionnaire (sleep quality, fatigue, stress, mood and muscle soreness). Microtechnology devices provided external load (average speed, high-speed running distance, player load and player load slow). Players provided RPE using the modified Borg category-ratio 10 RPE scale. Mixed-effect linear models revealed significant effects of wellness Z-score on player load and player load slow. Effects are reported with 95% confidence limits. A wellness Z-score of -1 corresponded to a -4.9 ± 3.1 and -8.6 ± 3.9% reduction in player load and player load slow, respectively, compared to those without reduced wellness. Small significant effects were also seen in the average speed:RPE and player load slow:RPE models. A wellness Z-score of -1 corresponded to a 0.43 ± 0.38 m·min(-1) and -0.02 ± 0.01 au·min(-1) change in the average speed:RPE and player load slow:RPE ratios, respectively. Magnitude-based analysis revealed that the practical size of the effect of a pre-training perceived wellness Z-score of -1 would have on player load slow was likely negative. The results of this study suggests that monitoring pre-training perceived wellness may provide coaches with information about the intensity of output that can be expected from individual players during a training session.
Owoeye Oluwatoyosi Babatunde; Akodu Ashiyat; Oladokun Bayonle; Akinbo Sunday Rufus
Abstract Background Basketball is the second most popular sport in Nigeria after football and is commonly played by adolescents. Prospective studies on adolescent basketball players in Nigeria are lacking. Such studies will help to develop injury counter-measures. Hence, this study aimed at determining the incidence and pattern of injuries among adolescent basketball players in Nigeria. Methods A prospective observational study involving 141 adolescent basketball players (75 boys and 66 girls...
Drafting players is crucial for a team’s success. We describe a data-driven interpretable approach for assessing prospects in the National Hockey League and National Basketball Association. Previous approaches have built a predictive model based on player features, or derived performance predictions from comparable players. Our work develops model tree learning, which incorporates strengths of both model-based and cohort-based approaches. A model tree partitions the feature space according to...
Weakley, JJS; Till, K; Roe, G; Darrall-Jones, J; Phibbs, P; Read, D; Jones, B
Adolescent rugby players benefit from the implementation of resistance training. However resistance training practices and how they influence short-term physical change is unknown. Therefore the purpose of this study was to quantify resistance training practices, evaluate physical development, and relate these changes to resistance training variables across 12-weeks in adolescent rugby union players. Thirty-five male adolescent rugby union players participated in the study with subjects compl...
Butler, Robert J.; Lehr, Michael E.; Fink, Michael L.; Kiesel, Kyle B.; Plisky, Phillip J.
Background: Field expedient screening tools that can identify individuals at an elevated risk for injury are needed to minimize time loss in American football players. Previous research has suggested that poor dynamic balance may be associated with an elevated risk for injury in athletes; however, this has yet to be examined in college football players. Hypothesis: To determine if dynamic balance deficits are associated with an elevated risk of injury in collegiate football players. It was hy...
Kaplan, Lee D; Flanigan, David C; Norwig, John; Jost, Patrick; Bradley, James
Shoulder injuries are the fourth most common musculoskeletal injury encountered in American football players. There is little information in the literature on the role of playing position in the type of shoulder injuries seen. There is a high prevalence of shoulder injuries in elite collegiate American football players, with type of injury varying by playing position. Cohort study (prevalence); Level of evidence, 3. A total of 336 elite collegiate American football players were invited to the National Football League Combine for physical testing and medical evaluation. Current and historical data were evaluated for the purpose of this study, and all players underwent radiographic examinations, including plain radiographs and/or magnetic resonance imaging when necessary. All shoulder pathological conditions and shoulder surgical procedures were recorded. Players were categorized by position for the analysis of position-specific trends. Of the players, 50% had a history of shoulder injuries, with a total of 226 shoulder injuries (1.3 injuries per player injured); 56 players (34%) had a total of 73 surgeries. The most common injuries were acromioclavicular separation (41%), anterior instability (20%), rotator cuff injury (12%), clavicle fracture (4%), and posterior instability (4%). The most common surgeries performed were anterior instability reconstruction (48%), Mumford/Weaver-Dunn surgery (15%), posterior instability surgery (10%), and rotator cuff surgery (10%). Shoulder injuries were more common in quarterbacks and defensive backs. Surgery was more common in linebackers or linemen. A history of anterior instability was more common in defensive players, with surgery required 76% of the time. Linemen had more rotator cuff injuries and posterior instability than players in other positions. Shoulder injuries are common injuries in elite collegiate football players, with one-third undergoing surgical procedures. There are definitive trends in the types of injuries
Benzidane, Houcine; Mokrani, Djamel; Zerf, Mohammed
The research aims to determine the effect of a weighted basketball balls training program on some physical performance via wheelchair basketball players. The sample was selected in an intended manner including 20 players’. Divided into two equal groups (experimental 10 players, control 10 players) for the sports season 2016/2017. As protocol experimental, our training program for the experimental group was applied under researchers’ supervision, using Weighted basketball balls in the opposite...
Full Text Available In the article the technology of evaluation of potential capabilities of badminton players is displayed 12-14 years. The functional, pedagogical and psychophysiological criteria which became a component parts of the developed analytical models of sportsmen-badminton players are explored. The criterion for the quantitative estimation of perspective is offered, which allows on the 9-ti point scale to estimate perspective of badminton players on the stage of preliminary base preparation.
Full Text Available The differences of individual-psychological characteristics of young handball players playing in different game roles. It is shown the relationship of certain personality characteristics of athletes with a line of attack handball players. In research took part handball players at the age of 15-17 years. It is analyzed data from questionnaires by R. Kettela and R. Rusalova. Evaluated the differences in the properties of the temperament handball players of different roles. Established that the distribution of game functions athletes must take into account their individual psychological characteristics.
Al Ghobain, M; Konbaz, M S; Almassad, A; Alsultan, A; Al Shubaili, M; AlShabanh, O
To estimate the lifetime prevalence and address the attitudes and knowledge of using prohibited substances (doping) among sport players in Saudi Arabia. A cross-sectional survey carried out using systematic random sampling technique among Saudi players of variable sports attending the sport clubs, stadiums, and sport fields (70 sport clubs, 22 types of sports belong to 22 Saudi sport federations were visted in 18 cities from all regions of Saudi Arabia). A total of 1142 male sport players were interviewed with main age of 24. The prevalence of using prohibited substances (doping) was 4.3 %. The main reason for using prohibited substances was to improve performance (69 %). The prevalence of using food supplements (not prohibited) was 38.4 %. Among the players, 30 % of them believe that such behavior is against the spirit of sport while 70 % of the players are aware of punishment against doping. 65 % of players admitted that they received advice on prohibited substances. Higher rate of using prohibited substances (doping) among Saudi players was associated with low education, age below 20 years, previous use of food supplements and lack of punishment awareness. Using prohibited substances (doping) among Saudi sport players is common. Players believe that such use is against the spirit of the sport and they are aware about its punishment, despite this, they are still using prohibited substances.
Alexander Ulbricht, Jaime Fernandez-Fernandez, Alberto Mendez-Villanueva, Alexander Ferrauti
Full Text Available The aims of the study were to test: 1 whether the relative age effect (RAE was prevalent in young (U12-U18 German male tennis players; 2 the potential influence of age and/or skill level on RAE and 3 whether maturity, anthropometric and fitness measures vary according to birth date distribution in elite youth tennis players. For the present study the following male populations were analysed: Overall German population (n = 3.216.811, all players affiliated to the German Tennis Federation (DTB (n = 120.851, players with DTB official ranking (n = 7165, regional (n = 381 and national (n = 57 squads (11-17 years old, as well as the top 50 German senior players were analyzed. RAEs were more prevalent at higher competitive levels with more players born in the first quarter of the year compared with the reference population for ranked (29.6%, regional (38.1% and national (42.1% players. No systematic differences were found in any of the maturity, anthropometric and fitness characteristics of the regional squad players born across different quarters. RAEs are present in the DTB competitive system and it was more pronounced at higher competitive levels. Compared with early born, late born players who were selected into elite squads did not differ in maturation, anthropometric and fitness characteristics.
Shaker, Noor; Yannakakis, Georgios N.; Asteriadis, Stylianos
present dierent types of information that have been extracted from game context, player preferences and perception of the game, as well as user features, automatically extracted from video recordings.We run a number of initial experiments to analyse players' behavior while playing video games as a case......Recognizing players' aective state while playing video games has been the focus of many recent research studies. In this paper we describe the process that has been followed to build a corpus based on game events and recorded video sessions from human players while playing Super Mario Bros. We...
Ramzan, M; Khan, M K
We present a quantization scheme for a three-player Prisoner's Dilemma game. It is shown that entanglement plays a dominant role in the three-player quantum game. Four different types of payoffs are identified on the basis of different combinations of initial state and measurement basis entanglement parameters. A relation among these different payoffs is also established. We also study the communication aspects of the three-player game. By exploiting different combinations of initial state and measurement basis entanglement parameters, we establish a relationship for the information shared among the parties. It is seen that the strategies of the players act as carriers of information in quantum games
Zmijewski, P.; Jimenez-Olmedo, J.M.; Jové-Tossi, M.A.; Martínez-Carbonell, A.; Suárez-Llorca, C.; Andreu-Cabrera, E.
The primary aim of this study was to examine the effects of 6-week strength training with whole body vibration (WBV) on leg strength and jumping performance in volleyball and beach volleyball players. Twenty-three sub-elite male volleyball (VB; n=12) and beach volleyball players (BVB; n=11) aged 21.2±3.0 years were divided into two groups and subjected to 6 weeks of strength training (three one-hour sessions per week): (I) 12 players (6 VB and 6 BVB players) underwent training with WBV (30-40 Hz, 1.7-2.5 mm, 3.0-5.7 g), and (II) 11 players (6 VB and 5 BVB players) underwent traditional strength training. Squat jump (SJ) and countermovement squat jump (CMJ) measurements by the Ergo Tester contact platform and maximum leg press test (1RM) were conducted. Three-factor (2 time x 2 WBV use x 2 discipline) analysis of variance for SJ, CMJ and 1RM revealed a significant time main effect (pvolleyball and beach volleyball players increases leg strength more and leads to greater improvement in jump performance than traditional strength training, but greater improvements can be expected in beach volleyball players than in volleyball players. PMID:25187676
Vaeyens, R; Zeuwts, L; Philippaerts, R; Lenoir, M
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%; pvolleyball and suggests that expert players extract more information from parafoveal regions. PMID:25609887
Full Text Available Purpose: to expose the features of display of self-appraisal for the hockey players of high class of different playing position. Material and Methods: for the exposure of level of self-appraisal for hockey players, information of sportsmen of high class, taking part in the matches of the Kontinental hockey league (KHL in a season 2013–2014 was probed sixteen hockey players, having a sporting digit MS and MSWC, took part in researches. Methods were used: pedagogical supervision, pedagogical analysis and generalization of front-rank experience, psychological testing, analysis of data of the special scientific-methodical literature, expert questioning, an analysis of data is the Internet. Results: findings allowed to set that the players of line of attack (central and extreme forward have more high level of self-appraisal for certain, than players of defence and hockey goalkeepers. This tendency is looked over both on the separate constituents of self-appraisal and on the whole on all spectrums of the studied indexes. The got results of researches rotined that the hockey players of high class had or middle or high level of self-appraisal. Among testable hockey players, players were not exposed with the low level of self-appraisal. Conclusions: the exposed distinctions in the level of self-appraisal of hockey players of high class can be used for diagnostics of playing predisposition and choice of playing line of business in a command.
López-Valenciano, Alejandro; Ayala, Francisco; Vera-García, Francisco J; de Ste Croix, Mark; Hernández-Sánchez, Sergio; Ruiz-Pérez, Iñaki; Cejudo, Antonio; Santonja, Fernando
Limited ranges of motion (ROM) have been considered as a primary risk factor for some football injuries, but only a few studies have analysed differences in lower extremity joints. The main purposes were (a) to describe the lower extremity ROM profile in professional football players; and (b) to examine differences between goalkeepers and outfield players. 82 professional male football players from 4 teams were measured in the 2013 pre-season. Measures of passive hip (flexion with knee flexed [PHFKF] and extended [PHFKE], extension [PHE], abduction [PHA], external [PHER] and internal [PHIR] rotation), knee (flexion [PKF]) and ankle (dorsiflexion with knee flexed [ADFKF] and extended [ADFKE]) ROMs were taken. Magnitude-based inferences exploring differences between player position and limb were made. 46% of all participants showed restricted PHFKE and/or around 30% showed restricted ADFKF ROM values. Contrarily, most players reported normal PHFKF, PHE, PHIR and PHER as well as PKF ROM scores with percentage values close to 100%. Bilateral meaningful differences for PHA, PHIR and PHER were found in approximately 30% of outfield players and goalkeepers. Statistical analysis found trivial differences between players for PHFKE, PHE, PHIR, PHER, ADFKE and ADFKF. However, moderate differences between players were found for PHFKF, PHA and PKF, with goalkeepers demonstrating higher values than outfield players. The findings of this study reinforce the necessity of prescribing exercises aimed at improving PHFKE and ADFKF ROM within everyday football training routines. In addition, as some bilateral deficits were observed, unilateral training should be considered where appropriate.
Vandenbroucke, Nicolas; Macaire, Ludovic; Postaire, Jack-Gerard
Soccer is a very popular sport all over the world, Coaches and sport commentators need accurate information about soccer games, especially about the players behavior. These information can be gathered by inspectors who watch the soccer match and report manually the actions of the players involved in the principal phases of the game. Generally, these inspectors focus their attention on the few players standing near the ball and don't report about the motion of all the other players. So it seems desirable to design a system which automatically tracks all the players in real- time. That's why we propose to automatically track each player through the successive color images of the sequences acquired by a fixed color camera. Each player which is present in the image, is modelized by an active contour model or snake. When, during the soccer match, a player is hidden by another, the snakes which track these two players merge. So, it becomes impossible to track the players, except if the snakes are interactively re-initialized. Fortunately, in most cases, the two players don't belong to the same team. That is why we present an algorithm which recognizes the teams of the players by pixels representing the soccer ground which must be withdrawn before considering the players themselves. To eliminate these pixels, the color characteristics of the ground are determined interactively. In a second step, dealing with windows containing only one player of one team, the color features which yield the best discrimination between the two teams are selected. Thanks to these color features, the pixels associated to the players of the two teams form two separated clusters into a color space. In fact, there are many color representation systems and it's interesting to evaluate the features which provide the best separation between the two classes of pixels according to the players soccer suit. Finally, the classification process for image segmentation is based on the three most
Kaplan, Lee D; Jost, Patrick W; Honkamp, Nicholas; Norwig, John; West, Robin; Bradley, James P
We conducted a study on the risk for foot and ankle injuries in college football players on the basis of injury type and player position. In February 2006, we evaluated 320 intercollegiate football players at the National Football League Combine. All pathologic conditions and surgical procedures of the foot and ankle were recorded, and data were analyzed by player position to detect any trends. Seventy-two percent (n = 231) of the players had a history of foot and ankle injuries, with a total of 287 foot and ankle injuries (1.24 injuries/player injured). The most common injuries were lateral ankle sprain (n = 115), syndesmotic sprain (50), metatarsophalangeal dislocation/turf toe (36), and fibular fracture (25). Foot and ankle injuries were most common in kickers/punters (100% incidence), special teams (100%), running backs (83%), wide receivers (83%), and offensive linemen (80%). Lateral ankle sprains, the most common injuries, were treated surgically only 2.6% of the time. Offensive linemen were most likely to have had syndesmotic sprains (32%), and quarterbacks had the highest incidence of fibular fractures (16%). Foot and ankle injuries are common in collegiate football players, affecting 72% of players. Thirteen percent underwent surgical treatment. Trends are seen in the types of injuries for the different player positions.
Winn, Charles O N; Ford, Paul R; McNarry, Melitta A; Lewis, Jason; Stratton, Gareth
The developmental activities of rugby union players and their interaction with deprivation remain to be elucidated. Five-hundred and ninety elite junior rugby union players (14.8 ± 0.5 years) were split into deprivation quintiles. These players subsequently completed a participant history questionnaire to record their involvement in rugby and other sports. Players accumulated 1987 ± 1297 h in rugby between 6 and 15 years of age. During the mini rugby stage (6-10 years of age), players accumulated an average of 113 ± 105, 89 ± 69 and 43 ± 19 h per year in rugby play, practice and competition, respectively. Moreover, 461 players engaged in an average of two other sports during the mini rugby stage. During the junior rugby stage (11-15 years of age), players accumulated 179 ± 98, 115 ± 90 and 64 ± 26 h per year in rugby practice, play and competition, respectively, and 538 players took part in three other sports. Players who were more deprived accumulated less rugby hours and participated in fewer other sports, but age milestones were not different between deprivation quintiles. There were no differences within developmental activities in rugby between deprivation groups.
Carling, Christopher; Bloomfield, Jonathan
The aim of this study was to examine the effects of an early dismissal (after 5-min play) on work-rate in a professional soccer match. A computerised player tracking system was used to assess the work-rates of seven players who completed the match on a team with 10 players. A minute-by-minute analysis of the remaining 91min following the dismissal was performed for the total distance covered, the distance covered in five categories of movement intensity and the recovery time between high-intensity efforts for each player. The data were calculated for each half and for three equal intervals within each half and profiled against normative data for the same players obtained from the analysis of 15 games in the same season. Following the dismissal, the players covered a greater total distance than normal (pplayers may not always utilise their full physical potential as this match illustrated an increase in overall work-rate when reduced to 10 players. However, as a team with 10 players is likely to incur higher levels of fatigue, tactical alterations may be necessary and/or players may adopt a pacing strategy to endure the remainder of the match. Copyright (c) 2008 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Jakoi, Andre; O'Neill, Craig; Damsgaard, Christopher; Fehring, Keith; Tom, James
Athletic pubalgia is a complex injury that results in loss of play in competitive athletes, especially hockey players. The number of reported sports hernias has been increasing, and the importance of their management is vital. There are no studies reporting whether athletes can return to play at preinjury levels. The focus of this study was to evaluate the productivity of professional hockey players before an established athletic pubalgia diagnosis contrasted with the productivity after sports hernia repair. Cohort study; Level of evidence, 3. Professional National Hockey League (NHL) players who were reported to have a sports hernia and who underwent surgery from 2001 to 2008 were identified. Statistics were gathered on the players' previous 2 full seasons and compared with the statistics 2 full seasons after surgery. Data concerning games played, goals, average time on ice, time of productivity, and assists were gathered. Players were divided into 3 groups: group A incorporated all players, group B were players with 6 or fewer seasons of play, and group C consisted of players with 7 or more seasons of play. A control group was chosen to compare player deterioration or improvement over a career; each player selected for the study had a corresponding control player with the same tenure in his career and position during the same years. Forty-three hockey players were identified to have had sports hernia repairs from 2001 to 2008; ultimately, 80% would return to play 2 or more full seasons. Group A had statistically significant decreases in games played, goals scored, and assists. Versus the control group, the decreases in games played and assists were supported. Statistical analysis showed significant decreases in games played, goals scored, assists, and average time on ice the following 2 seasons in group C, which was also seen in comparison with the control group. Group B (16 players) showed only statistical significance in games played versus the control group
Mohr, Magni; Krustrup, Peter
The purpose of the present study was to examine the effects of additional in-season speed endurance production versus speed endurance maintenance training regimes on performance in competitive male soccer players. In a randomised controlled trial 18 male sub-elite players were exposed to additional...... during training were higher (psoccer players with superior...... speed endurance production (SEP) or speed endurance maintenance (SEM) training (two additional sessions/wk for 4 weeks) during the competitive season. Players performed the Yo-Yo intermittent recovery level 2 test (YYIR2) and a repeated sprint test (RST) pre- and postintervention. Yo-Yo IR2 performance...
Galanti, Giorgio; Stefani, Laura; Scacciati, Irene; Mascherini, Gabriele; Buti, Gabriella; Maffulli, Nicola
The study evaluated the dietary habits in two groups of young athletes, practicing two different sports: soccer players and cycling. The dietary habits of 47 athletes were investigated by questionnaire. Body Mass Index, Fat Mass, Free Fat Mass, Total Body, Intracellular, Extracellular Water and Phase Angle were measured by bioimpedance. The t-Student test for unpaired data was used. Significance was set at P soccer player group (soccer players: 63.8±1.96%; cyclists : 59.8 ± 8.7%; and soccer players 43.9±3.1%, cyclists 43.8 ±2.1%, respectively). Fatty mass of the soccer player group (14.5±2.9%) was significantly lower than that of the cyclist group (19.5±3.6%). Daily food intake was similar between the two groups (2844 kCal/die for soccer players /2630 kcal/die for cyclists), and lower than recommended. There was a low intake of Calcium (soccer players 1120±128.9 mg/die, cyclists 718±309 mg/die) for both groups, and a low intake of Potassium for soccer player (2576 mg/die ± 52.4) The caloric intake of adolescent athletes is lower than recommended. Body composition is significantly different between soccer players and cyclists.
Noda, Yuka; Iide, Kazuhide; Masuda, Reika; Kishida, Reina; Nagata, Atsumi; Hirakawa, Fumiko; Yoshimura, Yoshitaka; Imamura, Hiroyuki
The purpose of this study was: 1) to collect baseline data on nutrient intake in order to advise athletes about nutrition practices that might enhance performance, and 2) to evaluate the dietary iron intake and blood iron status of Japanese collegiate soccer players. The subjects were 31 soccer players and 15 controls. Dietary information was obtained with a food frequency questionnaire. The mean carbohydrate (6.9 g.kg-1 BW) and protein (1.3 g/kg) intakes of the soccer players were marginal in comparisons with recommended targets. The mean intakes of calcium, magnesium, vitamin A, B1, B2, and C were lower than the respective Japanese recommended dietary allowances (RDAs) or adequate dietary intakes in the soccer players. The mean intakes of green and other vegetables, milk and dairy products, fruits, and eggs were lower than the recommended targets. Thus, we recommended athletes to increase the intake of these foodstuffs along with slight increase in carbohydrate and lean meat. The mean intake of iron was higher than the respective RDA in the soccer players. A high prevalence of hemolysis (71%) in the soccer players was found. None of the soccer players and controls had anemia. Two soccer players had iron depletion, while none was found in the controls. In those players who had iron deficiency, the training load need to be lowered and/or iron intake may be increased.
Lidor, Ronnie; Ziv, Gal
The main objective of this article was to review a series of studies (n = 31) on physical attributes, physiological attributes, and on-court performances of female volleyball players. Empirical and practical knowledge emerging from studies on training-related issues in volleyball, such as body mass, fat-free mass, aerobic profile, strength, and agility and speed, should be integrated and applied when planning annual training programs for volleyball players. Based on our review, it was found that (a) players of a higher skill level are taller, somewhat heavier, and have higher vertical jump values than players of a lower level; (b) the aerobic profile of female volleyball players is similar to that of female basketball players; (c) ballistic resistance training can increase vertical jump values in female volleyball players; and (d) preseason conditioning should be conducted to prevent fatigue and reduced performance at the beginning of the season. Among the research concerns discussed in the article are that there is a lack data for on-court performance and time-motion analysis in female volleyball players and that more experimental/manipulative studies are needed to examine the effectiveness of different training programs on physiological attributes of female volleyball players. Two practical implications are suggested for volleyball and strength and conditioning coaches: (a) functional and nonfunctional overreaching should be carefully monitored when planning strength and conditioning programs, and (b) volleyball programs should include ballistic-type training.
The knee and ankle are the two most injured joints associated with the sport of badminton. This study evaluates biomechanical factors between professional and amateur badminton players using an injury mechanism model. The aim of this study was to investigate the kinematic motion and kinetic loading differences of the right knee and ankle while performing a maximal right lunge. Amateur players exhibited greater ankle range of motion (p badminton players presented a greater knee joint moment in the sagittal (p badminton players should account for these findings to reduce potential injury to the ankle and knee. PMID:28694684