What Level Design Elements Determine Flow? : How Light and Objects Guide the Player in Overwatch and Doom

OpenAIRE

Eliasson, David

2017-01-01

This thesis presents a comparative study between Overwatch (2016) and Doom (2016) to determine how these fast-paced games facilitate flow in their gameplay. The second chapter looks at formal definitions of flow and level design to establish a vocabulary for following chapters. Through formal analysis the level designs of both games are then examined to establish what elements in them guide players and keep the flow in gameplay. The thesis also examines how the initial gameplay design princip...

High School Football Players Use Their Helmets to Tackle Other Players Despite Knowing the Risks.

Science.gov (United States)

Kuriyama, Andrew M; Nakatsuka, Austin S; Yamamoto, Loren G

2017-03-01

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.

Bridging Media with the Help of Players

Science.gov (United States)

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.

The Role of Shoe Design in Ankle Sprain Rates Among Collegiate Basketball Players

Science.gov (United States)

Curtis, Claudia K; Laudner, Kevin G; McLoda, Todd A; McCaw, Steven T

2008-01-01

Context: Much of the recent focus in shoe design and engineering has been on improving athletic performance. Currently, this improvement has been in the form of “cushioned column systems,” which are spring-like in design and located under the heel of the shoe in place of a conventional heel counter. Concerns have been raised about whether this design alteration has increased the incidence of ankle sprains. Objective: To examine the incidence of lateral ankle sprains in collegiate basketball players with regard to shoe design. Design: Prospective cohort study. Setting: Certified athletic trainers at 1014 National Collegiate Athletic Association (NCAA)-affiliated schools sponsoring basketball during the 2005–2006 regular season were notified of an online questionnaire. Athletic trainers at 22 of the 1014 schools participated. Patients or Other Participants: A total of 230 basketball players (141 males, 89 females; age  =  20.2 ± 1.5 years) from NCAA Division I–III basketball programs sustained lateral ankle sprains. Main Outcome Measure(s): Ankle sprain information and type of shoe worn (cushioned column or noncushioned column) were collected via online survey. The incidence of lateral ankle sprains and type of shoes worn were compared using a chi-square analysis. Results: No difference was noted in ankle sprain incidence between groups (χ2  =  2.44, P  =  .20, relative risk  =  1.47, 95% confidence interval [CI]  =  0.32, 6.86). The incidence of ankle sprains was 1.33 per 1000 exposures in the cushioned column group (95% CI  =  0.62, 3.51) and 1.96 per 1000 exposures in the noncushioned column group (95% CI  =  0.51, 4.22). Conclusions: No increased incidence of ankle sprains was associated with shoe design. PMID:18523571

New Zealand rugby health study: motor cortex excitability in retired elite and community level rugby players.

Science.gov (United States)

Lewis, Gwyn N; Hume, Patria A; Stavric, Verna; Brown, Scott R; Taylor, Denise

2017-01-13

Rugby union is a high contact sport in which players frequently experience brain injuries. Acute brain injury is associated with altered corticomotor function. However, it is uncertain if long-term exposure to rugby is associated with any alterations in corticomotor function. The aim of the study was to assess measures of corticomotor excitability and inhibition in retired rugby players in comparison to retired non-contact sport players. The design was a cross-sectional study with three groups of retired athletes: elite rugby (n=23), community level rugby (n=28) and non-contact sport control (n=22). Assessments of corticomotor excitability were made using transcranial magnetic stimulation. Resting motor threshold was significantly higher and long-interval intracortical inhibition was greater in the elite rugby group compared to the control group. Participants in the two rugby groups had sustained significantly more concussions than the control group. We provide some evidence of altered corticomotor excitation and inhibition in retired elite rugby players in comparison to retired non-contact sport players. Given the absence of findings in the community rugby group, who had experienced a similar number of concussions, the association with previous brain injury is unclear.

The final TimeWarp: using form and content to support player experience and presence when designing location-aware mobile augmented reality games

OpenAIRE

Blum, Lisa; Wetzel, Richard; McCall, Roderick; Oppermann, Leif; Broll, Wolfgang

2012-01-01

Designing Augmented Reality location aware games requires an understanding of how form and content issues impact on presence. A study of 60 players was conducted using questionnaires, video analysis and interviews. The results indicate that content including: moral dilemmas, strong narratives, using real locations effectively and applying simple physical behavior within virtual characters to improve embodiment have a positive impact on player experience. The results are presented in ...

Player-Character Dynamics in Multi- Player Role Playing Games

DEFF Research Database (Denmark)

Tychsen, Anders; McIlwain, D.; Brolund, T.

2007-01-01

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...

Optimal development of rugby players: a case study | Rainsford ...

African Journals Online (AJOL)

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 ...

Achievement Goals, Motivational Climate and Sportspersonship: A Study of Young Handball Players

Science.gov (United States)

Stornes, Tor; Ommundsen, Yngvar

2004-01-01

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…

The NBA’s Maximum Player Salary and the Distribution of Player Rents

Directory of Open Access Journals (Sweden)

Kelly M. Hastings

2015-03-01

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.

Protective equipment and player characteristics associated with the incidence of sport-related concussion in high school football players: a multifactorial prospective study.

Science.gov (United States)

McGuine, Timothy A; Hetzel, Scott; McCrea, Michael; Brooks, M Alison

2014-10-01

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).

SPORTS SHOES PURCHASE INTENTION AMONG MALAYSIAN VOLLEYBALL PLAYERS VS. NON-VOLLEYBALL PLAYERS: A CONCEPTUAL PAPER

Directory of Open Access Journals (Sweden)

GOH PIN SIANG

2013-12-01

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.

Protective Equipment and Player Characteristics Associated With the Incidence of Sport-Related Concussion in High School Football Players

Science.gov (United States)

McGuine, Timothy A.; Hetzel, Scott; McCrea, Michael; Brooks, M. Alison

2015-01-01

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

Prospective Player-Reported Injuries in Female Youth Fast-Pitch Softball Players.

Science.gov (United States)

Smith, Matthew V; Davis, Randi; Brophy, Robert H; Prather, Heidi; Garbutt, Jane; Wright, Rick W

2015-01-01

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).

Does shoe heel design influence ground reaction forces and knee moments during maximum lunges in elite and intermediate badminton players?

Science.gov (United States)

Lam, Wing-Kai; Ryue, Jaejin; Lee, Ki-Kwang; Park, Sang-Kyoon; Cheung, Jason Tak-Man; Ryu, Jiseon

2017-01-01

Lunge is one frequently executed movement in badminton and involves a unique sagittal footstrike angle of more than 40 degrees at initial ground contact compared with other manoeuvres. This study examined if the shoe heel curvature design of a badminton shoe would influence shoe-ground kinematics, ground reaction forces, and knee moments during lunge. Eleven elite and fifteen intermediate players performed five left-forward maximum lunge trials with Rounded Heel Shoe (RHS), Flattened Heel Shoe (FHS), and Standard Heel Shoes (SHS). Shoe-ground kinematics, ground reaction forces, and knee moments were measured by using synchronized force platform and motion analysis system. A 2 (Group) x 3 (Shoe) ANOVA with repeated measures was performed to determine the effects of different shoes and different playing levels, as well as the interaction of two factors on all variables. Shoe effect indicated that players demonstrated lower maximum vertical loading rate in RHS than the other two shoes (P badminton lunge. The differences in impact loads and knee moments between elite and intermediate players may be useful in optimizing footwear design and training strategy to minimize the potential risks for impact related injuries in badminton.

Design and interpretation of anthropometric and fitness testing of basketball players.

Science.gov (United States)

Drinkwater, Eric J; Pyne, David B; McKenna, Michael J

2008-01-01

The volume of literature on fitness testing in court sports such as basketball is considerably less than for field sports or individual sports such as running and cycling. Team sport performance is dependent upon a diverse range of qualities including size, fitness, sport-specific skills, team tactics, and psychological attributes. The game of basketball has evolved to have a high priority on body size and physical fitness by coaches and players. A player's size has a large influence on the position in the team, while the high-intensity, intermittent nature of the physical demands requires players to have a high level of fitness. Basketball coaches and sport scientists often use a battery of sport-specific physical tests to evaluate body size and composition, and aerobic fitness and power. This testing may be used to track changes within athletes over time to evaluate the effectiveness of training programmes or screen players for selection. Sports science research is establishing typical (or 'reference') values for both within-athlete changes and between-athlete differences. Newer statistical approaches such as magnitude-based inferences have emerged that are providing more meaningful interpretation of fitness testing results in the field for coaches and athletes. Careful selection and implementation of tests, and more pertinent interpretation of data, will enhance the value of fitness testing in high-level basketball programmes. This article presents reference values of fitness and body size in basketball players, and identifies practical methods of interpreting changes within players and differences between players beyond the null-hypothesis.

A COMPARATIVE STUDY OF PERSONALITY OF INTERNATIONAL VOLLEYBALL PLAYERS OF BRAZIL AND INDIA

Directory of Open Access Journals (Sweden)

Govind Kadam

2010-06-01

Full Text Available The main objective was to study the personality of the volleyball players of India. All the players of Indian team and the players of Brazil team, who came for FIVB Men Volleyball World Championship held at Pune in August 2009, were selected for the study. They were administered the Cattell’s 16 PF questionnaire. The results wereanalyzed with the help of ‘t’ test which showed that there are significant differences found between Indian volleyball players and Brazilian Volleyball players on seven factors but not on nine factors of 16 PF Questionnaire. Indian players scored high on factor ‘F’, factor ‘I’ and factor ‘M’ whereas Brazilian players have scored high on factor ‘B’, factor ‘G’, factor ‘H’ and factor ‘L’. Indian players scored low on Factor B which means that they tend to be slow to learn and grasp and they were dull as compared with Brazilian team, and gives concrete and literal interpretation. This dullness simply represents poor functioning.

High School Football Players and Their Coaches: A Qualitative Study of Their Relationships

Science.gov (United States)

Skaza, Robert J.

2014-01-01

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…

An Optimized Player Taxonomy Model for Mobile MMORPGs with Millions of Users

OpenAIRE

You, Fang; Liu, Jianping; Guan, Xinjian; Wang, Jianmin; Zheng, Zibin; Tam, Peter

2011-01-01

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...

Injuries in male and female semi-professional football (soccer) players in Nigeria: prospective study of a National Tournament.

Science.gov (United States)

Owoeye, Oluwatoyosi Babatunde Alex; Aiyegbusi, Ayoola Ibifubara; Fapojuwo, Oluwaseun Akinleye; Badru, Oluwaseun Abdulganiyu; Babalola, Anike Rasheedat

2017-03-21

Research on the epidemiology of football injuries in Africa is very sparse despite its importance for injury prevention planning in a continent with limited sports medicine resources. The vast majority of studies available in literature were conducted in Europe and only a very few studies have prospectively reported the pattern of football injury in Africa. The purpose of this study was to evaluate the incidence and pattern of injuries in a cohort of male and female semi-professional football players in Nigeria. A prospective cohort design was conducted, in which a total of 756 players with an age range of 18-32 years (356 males and 300 females) from 22 different teams (12 male and 10 female teams), were prospectively followed in a National Football Tournament. Physiotherapists recorded team exposure and injuries. Injuries were documented using the consensus protocol for data collection in studies relating to football injury surveillance. An overall incidence of 113.4 injuries/1000 h (95% CI 93.7-136.0) equivalent to 3.7 injuries/match and time-loss incidence of 15.6 injuries/1000 h were recorded for male players and 65.9 injuries/1000 h (95% CI 48.9-86.8) equivalent to 2.2 injuries/match and time-loss incidence of 7.9 injuries/1000 h were recorded for female players. Male players had a significantly higher risk of injuries [IRR = 1.72 (95% CI 1.23-2.45)]. Injuries mostly affected the lower extremity for both genders (n = 81, 70% and n = 31, 62% for males and females respectively). Lower leg contusion (n = 22, 19%) and knee sprain (n = 9, 18%) were the most common specific injury types for male and female players respectively. Most of the injuries were as a result of contact with another player (n = 102, 88%-males; n = 48, 96%-females). Time-loss injuries were mostly estimated as minimal (n = 11, 69%) for male players and severe (n = 4, 66%) for female players. The overall incidence of injuries among Nigerian semi-professional football

Short-term Outcomes Following Concussion in the NFL: A Study of Player Longevity, Performance, and Financial Loss.

Science.gov (United States)

Navarro, Sergio M; Sokunbi, Olumide F; Haeberle, Heather S; Schickendantz, Mark S; Mont, Michael A; Figler, Richard A; Ramkumar, Prem N

2017-11-01

A short-term protocol for evaluation of National Football League (NFL) athletes incurring concussion has yet to be fully defined and framed in the context of the short-term potential team and career longevity, financial risk, and performance. To compare the short-term career outcomes for NFL players with concussions by analyzing the effect of concussions on (1) franchise release rate, (2) career length, (3) salary, and (4) performance. Cohort study; Level of evidence, 3. NFL player transaction records and publicly available injury reports from August 2005 to January 2016 were analyzed. All players sustaining documented concussions were evaluated for a change to inactive or DNP ("did not participate") status. A case-control design compared franchise release rates and remaining NFL career span. Career length was analyzed via survival analysis. Salary and performance differences were analyzed with publicly available contract data and a performance-scoring algorithm based on position/player level. Of the 5894 eligible NFL players over the 11-year period, 307 sustained publicly reported concussions resulting in the DNP injury protocol. Analysis of the probability of remaining in the league demonstrated a statistically significantly shorter career length for the concussion group at 3 and 5 years after concussion. The year-over-year change in contract value for the concussion group resulted in a mean overall salary reduction of $300,000 ± $1,300,000 per year (interquartile range, -$723,000 to $450,000 per year). The performance score reduction for all offensive scoring players sustaining concussions was statistically significant. This retrospective study demonstrated that NFL players who sustain a concussion face a higher overall franchise release rate and shorter career span. Players who sustained concussions may incur significant salary reductions and perform worse after concussion. Short-term reductions in longevity, performance, and salary after concussion exist and

Sex-specific differences in injury types among basketball players.

Science.gov (United States)

Ito, Eri; Iwamoto, Jun; Azuma, Koichiro; Matsumoto, Hideo

2015-01-01

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.

Player Transformation of Educational Multiplayer Games

DEFF Research Database (Denmark)

Magnussen, Rikke; Misfeldt, Morten

2004-01-01

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...

Does shoe heel design influence ground reaction forces and knee moments during maximum lunges in elite and intermediate badminton players?

Directory of Open Access Journals (Sweden)

Wing-Kai Lam

Full Text Available Lunge is one frequently executed movement in badminton and involves a unique sagittal footstrike angle of more than 40 degrees at initial ground contact compared with other manoeuvres. This study examined if the shoe heel curvature design of a badminton shoe would influence shoe-ground kinematics, ground reaction forces, and knee moments during lunge.Eleven elite and fifteen intermediate players performed five left-forward maximum lunge trials with Rounded Heel Shoe (RHS, Flattened Heel Shoe (FHS, and Standard Heel Shoes (SHS. Shoe-ground kinematics, ground reaction forces, and knee moments were measured by using synchronized force platform and motion analysis system. A 2 (Group x 3 (Shoe ANOVA with repeated measures was performed to determine the effects of different shoes and different playing levels, as well as the interaction of two factors on all variables.Shoe effect indicated that players demonstrated lower maximum vertical loading rate in RHS than the other two shoes (P < 0.05. Group effect revealed that elite players exhibited larger footstrike angle, faster approaching speed, lower peak horizontal force and horizontal loading rates but higher vertical loading rates and larger peak knee flexion and extension moments (P < 0.05. Analysis of Interactions of Group x Shoe for maximum and mean vertical loading rates (P < 0.05 indicated that elite players exhibited lower left maximum and mean vertical loading rates in RHS compared to FHS (P < 0.01, while the intermediate group did not show any Shoe effect on vertical loading rates.These findings indicate that shoe heel curvature would play some role in altering ground reaction force impact during badminton lunge. The differences in impact loads and knee moments between elite and intermediate players may be useful in optimizing footwear design and training strategy to minimize the potential risks for impact related injuries in badminton.

Influence of Glove Type on Mobility Performance for Wheelchair Rugby Players

NARCIS (Netherlands)

Mason, Barry S.; van der Woude, L. H. V.; Goosey-Tolfrey, V. L.

Objective: The purpose of this study was to determine the effectiveness of different glove types on mobility performance in a series of field tests specific to wheelchair rugby. Design: Ten international wheelchair rugby players performed three drills in each glove condition: (i) players' current

Wheeled mobility skills of wheelchair basketball players: a randomized controlled study.

Science.gov (United States)

Saltan, Asuman; Bakar, Yeşim; Ankarali, Handan

2017-05-01

The aim of this study was to assess the influence of wheelchair basketball sport on the functional abilities of wheelchair users. This is a randomized controlled study. Wheelchair basketball players (n = 111) and non-player (n = 85) were included in this study. We administered the questionnaire version of the wheelchair skills test questionnaire (WST_Q), recording the participants' capacity and performance scores on each of 32 skills. Player group have the baseline values of WST_Q higher than control group. The mean total percentage score of player group was significantly greater than control group (p skills-sports relationship is reciprocal. With increased wheelchair skills, people may be more inclined to engage in sports; subsequently, with greater sports, wheelchair skills could improve. Wheelchair mobility skills during clinical rehabilitation should reflect the daily activities and needs of each wheelchair user. WST-Q provides advantages in terms of requiring less time and material in using of clinical.

A qualitative vision of artificial turf football fields: Elite players and ...

African Journals Online (AJOL)

This study identified the most important parameters for the design and safety of artificial turf football fields according to professional footballers and coaches. Two semi-structured interviews were conducted. The sample consisted of 32 professional players and 25 professional coaches. The players and coaches emphasised ...

An Optimized Player Taxonomy Model for Mobile MMORPGs with Millions of Users

Directory of Open Access Journals (Sweden)

Fang You

2011-01-01

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.

Training habits and injuries of masters' level football players: a preliminary report.

Science.gov (United States)

Newsham-West, R; Button, C; Milburn, P D; Mündermann, A; Sole, G; Schneiders, A G; Sullivan, S J

2009-05-01

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.

Interpersonal stress, performance level, and parental support : A Longitudinal study among highly skilled young soccer players

NARCIS (Netherlands)

Van Yperen, N.W.

1995-01-01

This study of 65 highly skilled young male soccer players (mean age = 16.6 years) employed a 7-month longitudinal design to examine the causal relationship between performance level and interpersonal stress within the team. Particular attention was paid to the moderating effect of parental support.

Evaluating the Impact of Player Experience in the Design of a Serious Game for Upper Extremity Stroke Rehabilitation.

Science.gov (United States)

Cordeiro d'Ornellas, Marcos; Cargnin, Diego João; Cervi Prado, Ana Lúcia

2015-01-01

Video games have become a major entertainment industry and one of the most popular leisure forms, ranging from laboratory experiments to a mainstream cultural medium. Indeed, current games are multimodal and multidimensional products, relying on sophisticated features including not only a narrative-driven story but also impressive graphics and detailed settings. All of these elements helped to create a seamless and appealing product that have resulted in a growing number of players and in the number of game genres. Although video games have been used in education, simulation, and training, another application that exploits serious gaming is the exploration of player experience in the context of game research. Recent advances in the natural user interfaces and player experience have brought new perspectives on the in-game assessment of serious games. This paper evaluates the impact of player experience in the design of a serious game for upper extremity stroke rehabilitation. The game combines biofeedback and mirror neurons both in single and multiplayer mode. Results have shown that the game is a feasible solution to integrate serious games into the physical therapy routine.

Sex-specific differences in injury types among basketball players

Directory of Open Access Journals (Sweden)

Ito E

2014-12-01

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

Towards Player-Driven Procedural Content Generation

DEFF Research Database (Denmark)

Shaker, Noor; Yannakakis, Georgios N.; Togelius, Julian

2012-01-01

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....

The Effectiveness Evaluation among Different Player-Matching Mechanisms in a Multi-Player Quiz Game

Science.gov (United States)

Tsai, Fu-Hsing

2016-01-01

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…

Effect of exercise on lipid peroxidation in student soccer players

OpenAIRE

Puspaningtyas, Desty Ervira; Afriani, Yuni; Mahfida, Silvi Lailatul; Kushartanti, Wara; Farmawati, Arta

2018-01-01

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...

A study of the effectiveness of MP3 players to support family carers of people living with dementia at home.

Science.gov (United States)

Lewis, Virginia; Bauer, Michael; Winbolt, Margaret; Chenco, Carol; Hanley, Francine

2015-03-01

Music can be therapeutic to people with dementia; however, little is known about its effect on the family carers. This project aimed to (1) assess the effects of MP3 player use by a person with dementia on caregivers' mental health and wellbeing, including their self-care and health-promoting behavior and (2) determine whether MP3 player use increases caregivers' self-reported capacity to cope with their role. A pre-post quantitative and qualitative design was used. Carers completed a survey prior to commencing and four weeks after using the player. The survey included validated measures to assess the level of stress and coping among carers. Carers also kept a diary of the way they used the MP3 player. Half of the carers were interviewed about their experiences at the end of the study. Of 59 people who started using the MP3 player, 51 carers completed the four-week study period and surveys. Use of the MP3 player significantly decreased psychological distress, significantly improved the mental health and wellbeing of carers, significantly increased caregiver self-efficacy to manage symptoms of dementia, and was reported to provide valued respite from the high level of vigilance required for caring for a person with dementia. An MP3 player loaded with music can be a low cost and relatively simple and effective additional strategy to support families caring for people with dementia in the community.

A comparison of static near stereo acuity in youth baseball/softball players and non-ball players.

Science.gov (United States)

Boden, Lauren M; Rosengren, Kenneth J; Martin, Daniel F; Boden, Scott D

2009-03-01

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.

Injuries in Professional Male Soccer Players in the Netherlands: A Prospective Cohort Study

Science.gov (United States)

Stubbe, Janine H.; van Beijsterveldt, Anne-Marie M. C.; van der Knaap, Sissi; Stege, Jasper; Verhagen, Evert A.; van Mechelen, Willem; Backx, Frank J. G.

2015-01-01

Context: Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective: To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design: Cohort study. Setting: The Dutch premier soccer league. Patients or Other Participants: During the 2009–2010 soccer season, a total of 217 professional soccer players from 8 teams were prospectively followed. Main Outcome Measure(s): The medical staff recorded time-loss injuries, including information on injuries (ie, type, body part, duration) and exposure data for training sessions and matches. Results: A total of 286 injuries were recorded, affecting 62.7% of the players. The overall injury incidence was 6.2 injuries per 1000 player-hours, 2.8 in training sessions and 32.8 in matches. Most of the recorded injuries were acute (68.5%). Eight percent of the injuries were classified as recurrent. Injuries were most likely to be located in the lower extremities (82.9%). Injury time loss ranged from 1 to 752 days, with a median of 8 days. Knee injuries had the greatest consequences in terms of days of absence from soccer play (on average, 45 days). The most common diagnosis was muscle/tendon injury of the lower extremities (32.9%). Conclusions: Injury risk in the Dutch premier soccer league is high, especially during matches. Preventive measures should focus on the most common diagnoses, namely, muscle/tendon injuries of the lower extremities. PMID:25531144

PARTICIPATION OF MINI-BASKETBALL PLAYERS DURING SMALL-SIDED COMPETITIONS

Directory of Open Access Journals (Sweden)

M\\u00AA Isabel Pi\\u00F1ar

2009-01-01

Full Text Available This study presents the differences of competition between mini-basketball with the traditional rules (5-a-side and minibasket with rule modifications (3-a-side such as: reduced number of players on court, compulsory participation in 2 of the match's 4 periods, reduced court size, placing the free throw line at 3m from the basket, and including a three-point line. The sample that was selected included 47 mini-basketball players, and the study was carried out using a quasi-experimental design without a control group. The aim was to determine the effect of rule modifications on the participation of the player with the ball. It was demonstrated that the degree of individual participation is greater in mini-basketball with modified rules.

Exploring Self-regulation of More or Less Expert College-Age Video Game Players: A Sequential Explanatory Design.

Science.gov (United States)

Yilmaz Soylu, Meryem; Bruning, Roger H

2016-01-01

This study examined differences in self-regulation among college-age expert, moderately expert, and non-expert video game players in playing video games for fun. Winne's model of self-regulation (Winne, 2001) guided the study. The main assumption of this study was that expert video game players used more processes of self-regulation than the less-expert players. We surveyed 143 college students about their game playing frequency, habits, and use of self-regulation. Data analysis indicated that while playing recreational video games, expert gamers self-regulated more than moderately expert and non-expert players and moderately expert players used more processes of self-regulation than non-experts. Semi-structured interviews also were conducted with selected participants at each of the expertise levels. Qualitative follow-up analyses revealed five themes: (1) characteristics of expert video gamers, (2) conditions for playing a video game, (3) figuring out a game, (4) how gamers act and, (5) game context. Overall, findings indicated that playing a video game is a highly self-regulated activity and that becoming an expert video game player mobilizes multiple sets of self-regulation related skills and processes. These findings are seen as promising for educators desiring to encourage student self-regulation, because they indicate the possibility of supporting students via recreational video games by recognizing that their play includes processes of self-regulation.

Exploring Self-regulation of More or Less Expert College-Age Video Game Players: A Sequential Explanatory Design

Science.gov (United States)

Yilmaz Soylu, Meryem; Bruning, Roger H.

2016-01-01

This study examined differences in self-regulation among college-age expert, moderately expert, and non-expert video game players in playing video games for fun. Winne's model of self-regulation (Winne, 2001) guided the study. The main assumption of this study was that expert video game players used more processes of self-regulation than the less-expert players. We surveyed 143 college students about their game playing frequency, habits, and use of self-regulation. Data analysis indicated that while playing recreational video games, expert gamers self-regulated more than moderately expert and non-expert players and moderately expert players used more processes of self-regulation than non-experts. Semi-structured interviews also were conducted with selected participants at each of the expertise levels. Qualitative follow-up analyses revealed five themes: (1) characteristics of expert video gamers, (2) conditions for playing a video game, (3) figuring out a game, (4) how gamers act and, (5) game context. Overall, findings indicated that playing a video game is a highly self-regulated activity and that becoming an expert video game player mobilizes multiple sets of self-regulation related skills and processes. These findings are seen as promising for educators desiring to encourage student self-regulation, because they indicate the possibility of supporting students via recreational video games by recognizing that their play includes processes of self-regulation. PMID:27729881

Exploring Self-Regulation of More or Less Expert College-Age Video Game Players: A Sequential Explanatory Design

Directory of Open Access Journals (Sweden)

Meryem YILMAZ SOYLU

2016-09-01

Full Text Available This study examined differences in self-regulation among college-age expert, moderately expert, and non-expert video game players in playing video games for fun. Winne’s model of self-regulation (Winne, 2001 guided the study. Main assumption of this study was that expert video game players used more processes of self-regulation than the less-expert players. We surveyed 143 college students about their game playing frequency, habits, and use of self-regulation. Data analysis indicated that while playing recreational video games, expert gamers self-regulated more than moderately expert and non-expert players and moderately expert players used more processes of self-regulation than non-experts. Semi-structured interviews also were conducted with selected participants at each of the expertise levels. Qualitative follow-up analyses revealed five themes: 1 characteristics of expert video gamers, 2 conditions for playing a video game, 3 figuring out a game, 4 how gamers act and, 5 game context. Overall, findings indicated that playing a video game is a highly self-regulated activity and that becoming an expert video game player mobilizes multiple sets of self-regulation related skills and processes. These findings are seen as promising for educators desiring to encourage student self-regulation, because they indicate the possibility of supporting students via recreational video games by recognizing that their play includes processes of self-regulation.

Preventing knee injuries in adolescent female football players - design of a cluster randomized controlled trial [NCT00894595].

Science.gov (United States)

Hägglund, Martin; Waldén, Markus; Atroshi, Isam

2009-06-23

Knee injuries in football are common regardless of age, gender or playing level, but adolescent females seem to have the highest risk. The consequences after severe knee injury, for example anterior cruciate ligament (ACL) injury, are well-known, but less is known about knee injury prevention. We have designed a cluster randomized controlled trial (RCT) to evaluate the effect of a warm-up program aimed at preventing acute knee injury in adolescent female football. In this cluster randomized trial 516 teams (309 clusters) in eight regional football districts in Sweden with female players aged 13-17 years were randomized into an intervention group (260 teams) or a control group (256 teams). The teams in the intervention group were instructed to do a structured warm-up program at two training sessions per week throughout the 2009 competitive season (April to October) and those in the control group were informed to train and play as usual. Sixty-eight sports physical therapists are assigned to the clubs to assist both groups in data collection and to examine the players' acute knee injuries during the study period. Three different forms are used in the trial: (1) baseline player data form collected at the start of the trial, (2) computer-based registration form collected every month, on which one of the coaches/team leaders documents individual player exposure, and (3) injury report form on which the study therapists report acute knee injuries resulting in time loss from training or match play. The primary outcome is the incidence of ACL injury and the secondary outcomes are the incidence of any acute knee injury (except contusion) and incidence of severe knee injury (defined as injury resulting in absence of more than 4 weeks). Outcome measures are assessed after the end of the 2009 season. Prevention of knee injury is beneficial for players, clubs, insurance companies, and society. If the warm-up program is proven to be effective in reducing the incidence of knee

COMPARATIVE STUDY OF 4 WEEKS OF DYNAMIC B ALANCE TRAINING PROGRAM IN COLLEGIATE FOOTBALL PLAYERS: RANDOMIZED CLINICAL TRIAL

Directory of Open Access Journals (Sweden)

Nisha

2015-03-01

Full Text Available BACKGROUND: Balance is highly integrative dynamic process involving coordination of multiple neurological pathways that allows for the maintenance of the COG over BOS . Football players often perform lower extremity passing , shooting , twisting , cutting and dribbling skills while wearing shoes , these actions require body to be in the equilibrium position to perform the task . This leads to t he conclusion of the great importance of the ability of balance in football . AIMS: 1 . To study the effect of 4 week multidirectional balance board training on dynamic balance in football players . 2 . To study the effect of 4 week Both Sides Up ball training on dynamic balance in football players . 3 . To compare the effect of multidirectional balance board training program and BOSU ball training program on dynamic balance in football players . STUDY DESIGN: Randomized Clinical trial . METHODS: Total of 60 competitive badminton players with age group between18 - 25 were recruited in this study . The participants were allocated into 2 groups viz ., Group A (multidirectional balance board training and Group B (BOSU ball Training for a period of 4 we eks . Participants were test for SEBT and vertical jump test on first day and after 4 weeks of balance training . STATISTICAL ANALYSIS: Student t test , Chi - Square Test . RESULTS: The data analysis and statistical inference showed that , after 4 weeks of balanc e training there was improvement in dynamic balance in both the groups but there was no significant difference in dynamic balance between two groups . As seen by difference in the SEBT and VJT scores pre and post training with p<0 . 001 . CONCLUSION: 4 weeks balance training using BOSU and multidirectional balance board is effective in improving dynamic balance and vertical jump performance in football players and also can be used as a component of multifaceted training to improve dynamic balance and game skills

Patellar tendinopathy in junior basketball players: a controlled clinical and ultrasonographic study of 268 patellar tendons in players aged 14-18 years.

Science.gov (United States)

Cook, J L; Khan, K M; Kiss, Z S; Griffiths, L

2000-08-01

Anterior knee pain is a common presenting complaint amongst adolescent athletes. We hypothesised that patellar tendinopathy may occur at a younger age than is generally recognised. Thus, we studied the patellar tendons in 134 elite 14- to 18-year-old female (n=64) and male (n=70) basketball players and 29 control swimmers (17 female, 12 male) clinically and with ultrasonography. We found that of 268 tendons, 19 (7%) had current patellar tendinopathy on clinical grounds (11% in males, 2% in females). Twenty-six percent of the basketball players' patellar tendons contained an ultrasonographic hypoechoic region. Ultrasonographic abnormality was more prevalent in the oldest tertile of players (17-18 years) than the youngest tertile (14-15.9 years). Of tendons categorised clinically as 'Never patellar tendinopathy', 22% had an ultrasonographic hypoechoic region nevertheless. This study indicates that patellar tendinopathy can occur in 14- to 18-year-old basketball players. Ultrasonographic tendon abnormality is 3 times as common as clinical symptoms.

How the Iranian Football Coaches and Players Know About Doping?

Science.gov (United States)

Seif Barghi, Tohid; Halabchi, Farzin; Dvorak, Jiri; Hosseinnejad, Heydar

2015-01-01

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

The Anthropometric Characteristics of Futsal Players Compared with Professional Soccer Players

Directory of Open Access Journals (Sweden)

Burdukiewicz Anna

2014-08-01

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

A COMPARISON OF THE ANTHROPOMETRIC PARAMETERS BETWEEN BASKETBALL PLAYERS, HANDBALL PLAYERS AND VOLLEYBALL PLAYERS

OpenAIRE

Florian Miftari; Juel Jarani; Dhimitraq Stratoberdha; Hazir Salihu

2017-01-01

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 ...

Role-player expectations regarding the education of nursing research.

Science.gov (United States)

Zeelie, S C; Bornman, J E; Botes, A C

2003-12-01

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.

Caffeine supplementation improves countermovement jump in youth soccer players: a pilot study

Directory of Open Access Journals (Sweden)

Juan Diego Hernández-Camacho

2017-07-01

Full Text Available Introduction: The objective of this study was to analyze the effect of caffeine ingestion in soccer performance, particularly in the countermovement jump test (CMJ. Material and methods: A total of 17 players from a U-19 amateur Spanish team participated in this pilot study. A double-blind placebo-controlled randomized experimental design was used in 2 different sessions (1.5 hour per session separated by 1 week. CMJ was collected at the beginning and at the end of sessions; Rating of Perceived Exertion (RPE was recorded. Players ingested caffeine or placebo at the beginning of session (minute 0 of session, providing a total of 4 mg of caffeine or a placebo per kg of body mass. Side effects from caffeine and placebo ingestions were analyzed. The effect sizes (ES were calculated using values for Cohen’s and Quantitative differences were assessed qualitatively (QA. Results: The jump height with caffeine supplementation at the beginning of training was 37.03 (±3.87 cm and at the end was 39.35 (±4.05 cm, obtaining significant improvements (p<0.05; ES: 0.56; QA: 99/1/0. Significant differences on CMJ at the end of the training session between caffeine and placebo groups were observed (39.35 [±4.05] cm vs. 36.85 [±3.15] cm; p<0.05; ES: 0.65; QA: 0/1/99. Significant differences on RPE between groups were observed. A non-significant tendency to suffer more side effects with caffeine ingestion was obtained. Conclusions: This study shows how the ingestion of 4 mg of caffeine per kg of body mass could be an ergogenic aid to improve soccer performance. However, further studies with bigger soccer players sample would be necessary to refute the present results.

Active Learning for Player Modeling

DEFF Research Database (Denmark)

Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad

2015-01-01

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....

Frontal lobe function in chess players.

Science.gov (United States)

Nejati, Majid; Nejati, Vahid

2012-01-01

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.

Knee joint position sense of roller hockey players: a comparative study.

Science.gov (United States)

Venâncio, João; Lopes, Diogo; Lourenço, Joaquim; Ribeiro, Fernando

2016-06-01

This study aimed to compare knee joint position sense of roller hockey players with an age-matched group of non-athletes. Forty-three male participants voluntarily participated in this cross-sectional study: 21 roller hockey players (mean age: 23.2 ± 4.2 years old, mean weight: 81.8 ± 9.8 kg, mean height: 180.5 ± 4.1 cm) and 22 age-matched non-athletes (mean age: 23.7 ± 3.9 years old, mean weight: 85.0 ± 6.2 kg, mean height: 181.5 ± 5.0 cm). Knee joint position sense of the dominant limb was evaluated using a technique of open-kinetic chain and active knee positioning. Joint position sense was reported using absolute, relative and variable angular errors. The main results indicated that the group of roller hockey players showed significantly lower absolute (2.4 ± 1.2º vs. 6.5 ± 3.2º, p ≤ 0.001) and relative (1.7 ± 2.1º vs. 5.8 ± 4.4º, p ≤ 0.001) angular errors in comparison with the non-athletes group. In conclusion, the results from this present study suggest that proprioceptive acuity, assessed by measuring joint position sense, is increased in roller hockey players. The enhanced proprioception of the roller hockey players could contribute to injury prevention and improved performance during sporting activities.

Technical player profiles related to the physical fitness of young female volleyball players predict team performance.

Science.gov (United States)

Dávila-Romero, C; Hernández-Mocholí, M A; García-Hermoso, A

2015-03-01

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.

Injuries in Professional Male Soccer Players in the Netherlands: A Prospective Cohort Study

NARCIS (Netherlands)

Stubbe, J.H.; Beijsterveldt, A.M. van; Knaap, S. van der; Stege, J.; Verhagen, E.; Mechelen, W. van; Backx, F.J.G.

2015-01-01

Context : Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective : To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design : Cohort

Ankle Sprain Injuries: A 2-Year Prospective Cohort Study in Female Greek Professional Basketball Players

Science.gov (United States)

Kofotolis, Nikolaos; Kellis, Eleftherios

2007-01-01

Context: Ankle sprains are a common basketball injury. Therefore, examination of risk factors for injury in female professional basketball players is worthwhile. Objective: To examine rates of ankle sprains, associated time missed from participation, and risk factors for injury during 2 consecutive seasons. Design: Prospective cohort study. Setting: Eighteen professional basketball facilities. Patients or Other Participants: We observed 204 players from 18 female professional basketball teams for 2 consecutive seasons during a 2-year period. Main Outcome Measure(s): Using questionnaires, we recorded the incidence of ankle sprains, participation time missed, and mechanisms of injury in games and practice sessions. Potential risk factors, such as age, body mass, height, training experience, and history of ankle sprain, were examined using multivariate logistic regression. Results: Fifty of the 204 participants sustained ankle injuries; injuries included 32 ankle sprains, which translated to an ankle sprain rate of 1.12 per 1000 hours of exposure to injury. The 32 players missed 224.4 training and game sessions and an average of 7.01 sessions per injury. Most injuries occurred in the key area of the basketball court and were the result of contact. Injury rates during games were higher than injury rates during practice sessions. Centers, followed by guards and forwards, had the highest rate of injury. Players who did not wear an external ankle support had an odds ratio of 2.481 for sustaining an ankle sprain. Conclusions: Female professional basketball athletes who did not wear an external ankle support, who played in the key area, or who functioned as centers had a higher risk for ankle sprain than did other players. PMID:18059995

Frontal Lobe Function in Chess Players

Directory of Open Access Journals (Sweden)

Vahid Nejati

2012-05-01

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.

An investigation of player to player character identification via personal pronouns

DEFF Research Database (Denmark)

Hichens, Michael; Drachen, Anders; Richards, Deborah

2012-01-01

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...

Study of trunk flexibility and body composition between football and badminton players

Directory of Open Access Journals (Sweden)

NANDALAL SINGH

2011-04-01

Full Text Available The purpose of the present study was an attempt to compare the flexibility (trunk flexibility and bodycomposition (percentage of body fat, total body fat and lean body mass between inter-college level malefootball and badminton players. Fifty (50 male inter-college level football players (N=25 and badmintonplayers (N=25 ranging between 17 to 25years were selected randomly from different colleges of PanjabUniversity, Chandigarh for this study. To compare the mean differences between the inter-college level footballand badminton players,t tests were computed using SPSS Software. Flexibility (trunk flexibility, and bodycomposition (percentage of body fat and total body fat were not found to be statistically significant

Knee movement patterns of injured and uninjured adolescent basketball players when landing from a jump: A case-control study

Directory of Open Access Journals (Sweden)

Grimmer Karen

2006-03-01

Full Text Available Abstract Background A common knee injury mechanism sustained during basketball is landing badly from a jump. Landing is a complex task and requires good coordination, dynamic muscle control and flexibility. For adolescents whose coordination and motor control has not fully matured, landing badly from a jump can present a significant risk for injury. There is currently limited biomechanical information regarding the lower limb kinetics of adolescents when jumping, specifically regarding jump kinematics comparing injured with uninjured adolescents. This study reports on an investigation of biomechanical differences in landing patterns of uninjured and injured adolescent basketball players. Methods A matched case-control study design was employed. Twenty-two basketball players aged 14–16 years participated in the study: eleven previously knee-injured and eleven uninjured players matched with cases for age, gender, weight, height and years of play, and playing for the same club. Six high-speed, three-dimensional Vicon 370 cameras (120 Hz, Vicon biomechanical software and SAS Version 8 software were employed to analyse landing patterns when subjects performed a "jump shot". Linear correlations determined functional relationships between the biomechanical performance of lower limb joints, and paired t-tests determined differences between the normalised peak biomechanical parameters. Results The average peak vertical ground reaction forces between the cases and controls were similar. The average peak ground reaction forces between the cases and controls were moderately correlated (r = -0.47. The control (uninjured players had significantly greater hip and knee flexion angles and significantly greater eccentric activity on landing than the uninjured cases (p Conclusion The findings of the study indicate that players with a history of knee injuries had biomechanically compromised landing techniques when compared with uninjured players matched for

Causal Attributions of Success and Failure and Mood States in Football Players

Directory of Open Access Journals (Sweden)

Szczepaniak Joanna

2016-12-01

Full Text Available Introduction. The aim of the study was to determine the causal attributions of success and failure in a football match in a group of football players, as well as to investigate the association of the players’ attributions with their level of achievement and the relationships between their causal attributions and affective states. Material and methods. The study involved 75 football players, including 44 players from the first league and 31 players from the third league. The research was carried out using the Profile of Mood States (POMS by D.M. McNair, M. Lorr, and L.F. Droppleman and a specially designed questionnaire concerning the causal attributions of success and failure. Results. It was found that the football players who participated in the study tended to attribute success to internal causes and failure to external causes. More frequent use of external attributions most likely had an adverse impact on the mood state of the players. Conclusion. Information concerning the attributions that a given player makes can be useful for coaches, as it can help them develop the athlete’s mental abilities more effectively. Beliefs related to attributions can be modified. It is worth considering the benefits of encouraging internal attributions in the case of success and external attributions in situations of failure.

Preventing knee injuries in adolescent female football players – design of a cluster randomized controlled trial [NCT00894595

Directory of Open Access Journals (Sweden)

Waldén Markus

2009-06-01

Full Text Available Abstract Background Knee injuries in football are common regardless of age, gender or playing level, but adolescent females seem to have the highest risk. The consequences after severe knee injury, for example anterior cruciate ligament (ACL injury, are well-known, but less is known about knee injury prevention. We have designed a cluster randomized controlled trial (RCT to evaluate the effect of a warm-up program aimed at preventing acute knee injury in adolescent female football. Methods In this cluster randomized trial 516 teams (309 clusters in eight regional football districts in Sweden with female players aged 13–17 years were randomized into an intervention group (260 teams or a control group (256 teams. The teams in the intervention group were instructed to do a structured warm-up program at two training sessions per week throughout the 2009 competitive season (April to October and those in the control group were informed to train and play as usual. Sixty-eight sports physical therapists are assigned to the clubs to assist both groups in data collection and to examine the players' acute knee injuries during the study period. Three different forms are used in the trial: (1 baseline player data form collected at the start of the trial, (2 computer-based registration form collected every month, on which one of the coaches/team leaders documents individual player exposure, and (3 injury report form on which the study therapists report acute knee injuries resulting in time loss from training or match play. The primary outcome is the incidence of ACL injury and the secondary outcomes are the incidence of any acute knee injury (except contusion and incidence of severe knee injury (defined as injury resulting in absence of more than 4 weeks. Outcome measures are assessed after the end of the 2009 season. Discussion Prevention of knee injury is beneficial for players, clubs, insurance companies, and society. If the warm-up program is proven to

Online Game Elements, Players and the Bond Between Them

OpenAIRE

Schweizer, Sandra

2017-01-01

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.

Physical fitness of elite Belgian soccer players by player position.

Science.gov (United States)

Boone, Jan; Vaeyens, Roel; Steyaert, Adelheid; Vanden Bossche, Luc; Bourgois, Jan

2012-08-01

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.

MythBusters, Musicians, and MP3 Players: A Middle School Sound Study

Science.gov (United States)

Putney, Ann

2011-01-01

Create your own speakers for an MP3 player while exploring the science of sound. Review of science notebooks, students' intriguing cabinet designs, and listening to students talk with a musician about the physics of an instrument show that complex concepts are being absorbed and extended with each new iteration. Science that matters to students…

Assessing the Energy Expenditure of Elite Female Soccer Players: A Preliminary Study.

Science.gov (United States)

Mara, Jocelyn K; Thompson, Kevin G; Pumpa, Kate L

2015-10-01

The aim of this study was to assess the total and exercise energy expenditure of elite female soccer players during a training week. Eight elite female soccer players wore SenseWear Mini Armbands (SWAs) for 7 consecutive days during the preseason phase of a national league competition. In addition, players wore 15-Hz GPSports tracking devices during 4 training sessions and a friendly game. Total energy expenditure, exercise energy expenditure, and training and game demands were collected from the SWA and GPSports devices. Mean daily energy expenditure for the game day, training days, and rest days were 12,242 kJ (SD = 603 kJ), 11,692 (SD = 274 kJ), and 9,516 (SD = 369 kJ), respectively, with significant differences shown between activities (p soccer players. Nutritional intake should be adjusted accordingly to avoid energy imbalances for optimal performance and recovery.

Player and Game Characteristics and Head Impacts in Female Youth Ice Hockey Players.

Science.gov (United States)

Reed, Nick; Taha, Tim; Greenwald, Richard; Keightley, Michelle

2017-08-01

  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.

Scapular Resting Position and Gleno-Humeral Movement Dysfunction in Asymptomatic Racquet Players: A Case-Control Study.

Science.gov (United States)

Shimpi, Apurv P; Bhakti, Shah; Roshni, Karnik; Rairikar, Savita A; Shyam, Ashok; Sancheti, Parag K

2015-12-01

Racquet sports, especially lawn tennis and badminton have been gaining popularity in Asian countries like India. With this increase in popularity, the injury rate in the sport has also increased. The study will help detect the presence of gleno-humeral movement dysfunction and scapular resting position abnormality in asymptomatic racquet players, thus providing basis for screening the players and allow the clinician to determine if the asymmetry is a normal adaptation in the player or an abnormal change associated with injury. 46 asymptomatic professional players were divided into a study group of 23 players (16 tennis and 7 badminton) and control group of 23 football players. Assessment of passive gleno-humeral range of motion and distance of spine and inferior angle of scapula from corresponding spinous process were measured bilaterally and between groups. There was statistically significant reduction in range of internal rotation (62.17 ± 8.09), extension (39.78 ± 4.12) and an increase in the external rotation (106.95 ± 7.49) of dominant compared to non-dominant arm of racquet players and a statistically significant decrease in internal rotation (78.69 ± 10.24), extension (44.78 ± 3.19), adduction (37.39 ± 6.54) and an increase in external rotation (102.6 ± 5.19) of dominant arm of racquet players compared to football players. Study also showed statistically significant increase in the spino-scapular distance at the level of inferior angle of scapula (10.23 ± 1.43) on dominant side compared to non-dominant. The dominant side scapula of asymptomatic racquet players showed increased external rotation and elevation as compared to the non-dominant side. Also, reduced shoulder internal rotation, extension and adduction and gain in shoulder external rotation was observed on the dominant side of racquet players when compared to the control group.

Vertical jump in female and male basketball players--a review of observational and experimental studies.

Science.gov (United States)

Ziv, Gal; Lidor, Ronnie

2010-05-01

The main purpose of this article was to review a series of studies (n=26; 15 observational and 11 experimental) examining vertical jump (VJ) performances in female and male basketball players. Information on the tests used in these studies and their specific protocols, and the training programs conducted to improve VJ ability in elite basketball players, was assessed. It was found that vertical jump values varied greatly, from 22 to 48 cm in female players and from 40 to 75 cm in male players. These large variations can be explained mostly by the differences in testing protocols (each VJ protocol examined different physiological pathways) and skill level of players. The variations in VJ values among studies were greatly reduced when they used the same protocol. In addition, short plyometric training sessions as part of the strength and conditioning program were found to enhance VJ performances in basketball players. Based on the reviewed studies, five limitations associated with the testing protocols and the strength and conditioning programs used in the studies were outlined, among them the use of multiple testing protocols and lack of experimental studies. Three recommendations for basketball and strength and conditioning coaches were suggested, for one of which was including plyometric training in the annual training program. 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

A COMPARATIVE STUDY BETWEEN TALENTED YOUNG GREEK AND GERMAN HANDBALL PLAYERS IN SOME PHYSICAL AND ANTHROPOMETRIC CHARACTERISTICS

Directory of Open Access Journals (Sweden)

H. Galal El-Din

2011-11-01

Full Text Available This international comparative study between talented young handball players in Germany and Greece investigated specific physical and anthropometric characteristics. This investigation of both elite profiles will allow us to determine the differences in the selection system for elite young handball players between the two countries. One hundred and sixty-two players participated in this study, 88 Greek young male players and 74 German young male players. For anthropometric tests the players were measured for body height, body mass and body mass index, arm span, hand length and hand spread. Physical fitness measurements were 30 m sprint, standing long jump, sit and reach flexibility, and 20 m shuttle run test. The results of this study demonstrate that Greek players were taller and heavier (p<0.01, had longer arm span and hand length (p<0.01, and performed better in 30 m sprint (p<0.01, standing long jump (p<0.01 and aerobic capacity (p<0.01. German players outperform in hand spread (p=0.03. While some of these differences can be explained by the different strategies and training methods, and also the training environment, the results do have important implications and effects in the physical condition of junior players.

Nutrient intake and food habits of soccer players: analyzing the correlates of eating practice.

Science.gov (United States)

García-Rovés, Pablo M; García-Zapico, Pedro; Patterson, Angeles M; Iglesias-Gutiérrez, Eduardo

2014-07-18

Despite the impact and popularity of soccer, and the growing field of soccer-related scientific research, little attention has been devoted to the nutritional intake and eating habits of soccer players. Moreover, the few studies that have addressed this issue suggest that the nutritional intake of soccer players is inadequate, underscoring the need for better adherence to nutritional recommendations and the development and implementation of nutrition education programs. The objective of these programs would be to promote healthy eating habits for male and female soccer players of all ages to optimize performance and provide health benefits that last beyond the end of a player's career. To date, no well-designed nutrition education program has been implemented for soccer players. The design and implementation of such an intervention requires a priori knowledge of nutritional intake and other correlates of food selection, such as food preferences and the influence of field position on nutrient intake, as well as detailed analysis of nutritional intake on match days, on which little data is available. Our aim is to provide an up-to-date overview of the nutritional intake, eating habits, and correlates of eating practice of soccer players.

The players of the photovoltaic sector in France

International Nuclear Information System (INIS)

Houot, G.

2012-01-01

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.)

Generative Agents for Player Decision Modeling in Games

DEFF Research Database (Denmark)

Holmgård, Christoffer; Liapis, Antonios; Togelius, Julian

2014-01-01

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...

Prevalence of Os Styloideum in National Hockey League Players

Science.gov (United States)

Greditzer, Harry G.; Hutchinson, Ian D.; Geannette, Christian S.; Hotchkiss, Robert N.; Kelly, Bryan T.; Potter, Hollis G.

2017-01-01

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

Impact locations and concussion outcomes in high school football player-to-player collisions.

Science.gov (United States)

Kerr, Zachary Y; Collins, Christy L; Mihalik, Jason P; Marshall, Stephen W; Guskiewicz, Kevin M; Comstock, R Dawn

2014-09-01

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.

Good Feedback for bad Players? A preliminary Study of ‘juicy’ Interface feedback

DEFF Research Database (Denmark)

Juul, Jesper; Jason, Begy

2016-01-01

The theories of game feel and juiciness claim that players will feel more competent, and that a game will be perceived as being of higher quality, when players are given large amounts of redundant audiovisual feedback in response to their actions. This poster describes a preliminary empirical study...

Prospective imaging study of asymptomatic patellar tendinopathy in elite junior basketball players.

Science.gov (United States)

Cook, J L; Khan, K M; Kiss, Z S; Purdam, C R; Griffiths, L

2000-07-01

To evaluate the ability of ultrasonography to predict eventual symptoms in an at-risk population, 52 elite junior basketball players' patellar tendons were studied at baseline and again 16 months later. The group consisted of 10 study tendons (ultrasonographically hypoechoic at baseline) and 42 control tendons (ultrasonographically normal at baseline). By design, all tendons were asymptomatic at baseline. No differences were noted between subjects and controls at baseline for age, height, weight, training hours, and vertical jump. Functional (P patellar tendon changes may resolve, but this is not necessary for an athlete to become asymptomatic. Qualitative or quantitative analysis of baseline ultrasonographic images revealed it was not possible to predict which tendons would develop symptoms or resolve ultrasonographically.

Neuroimaging of cognitive dysfunction and depression in aging retired National Football League players: a cross-sectional study.

Science.gov (United States)

Hart, John; Kraut, Michael A; Womack, Kyle B; Strain, Jeremy; Didehbani, Nyaz; Bartz, Elizabeth; Conover, Heather; Mansinghani, Sethesh; Lu, Hanzhang; Cullum, C Munro

2013-03-01

OBJECTIVES To assess cognitive impairment and depression in aging former professional football (National Football League [NFL]) players and to identify neuroimaging correlates of these dysfunctions. DESIGN We compared former NFL players with cognitive impairment and depression, cognitively normal retired players who were not depressed, and matched healthy control subjects. SETTING Research center in the North Texas region of the United States. PATIENTS Cross-sectional sample of former NFL players with and without a history of concussion recruited from the North Texas region and age-, education-, and IQ-matched controls. Thirty-four retired NFL players (mean age, 61.8 years) underwent neurological and neuropsychological assessment. A subset of 26 players also underwent detailed neuroimaging; imaging data in this subset were compared with imaging data acquired in 26 healthy matched controls. MAIN OUTCOME MEASURES Neuropsychological measures, clinical diagnoses of depression, neuroimaging mea-sures of white matter pathology, and a measure of cerebral blood flow. RESULTS Of the 34 former NFL players, 20 were cognitively normal. Four were diagnosed as having a fixed cognitive deficit; 8, mild cognitive impairment; 2, dementia; and 8, depression. Of the subgroup in whom neuroimaging data were acquired, cognitively impaired participants showed the greatest deficits on tests of naming, word finding, and visual/verbal episodic memory. We found significant differences in white matter abnormalities in cognitively impaired and depressed retired players compared with their respective controls. Regional blood flow differences in the cognitively impaired group (left temporal pole, inferior parietal lobule, and superior temporal gyrus) corresponded to regions associated with impaired neurocognitive performance (problems with memory, naming, and word finding). CONCLUSIONS Cognitive deficits and depression appear to be more common in aging former NFL players compared with healthy

Hip Strength Testing of Soccer Players With Long-Standing Hip and Groin Pain

DEFF Research Database (Denmark)

Rafn, Bolette S; Tang, Lars; Nielsen, Peter Martin

2016-01-01

OBJECTIVE: To investigate whether self-reported pain during hip strength testing correlates to a large degree with hip muscle strength in soccer players with long-standing unilateral hip and groin pain. DESIGN: Cross-sectional study. SETTING: Clinical assessments at Sports Orthopaedic Research...... Center-Copenhagen (SORC-C), Arthroscopic Centre Amager, Copenhagen University Hospital, Denmark. PARTICIPANTS: Twenty-four male soccer players with unilateral long-standing hip and groin pain. INTERVENTIONS: The soccer players performed 5 reliable hip muscle strength tests (isometric hip flexion...... strength (Spearman rho = -0.44, P = 0.016). CONCLUSIONS: Self-reported pain during testing does not seem to correlate with the majority of hip muscle strength tests used in soccer players with long-standing hip and groin pain....

Knee movement patterns of injured and uninjured adolescent basketball players when landing from a jump: a case-control study.

Science.gov (United States)

Louw, Quinette; Grimmer, Karen; Vaughan, Christopher

2006-03-07

A common knee injury mechanism sustained during basketball is landing badly from a jump. Landing is a complex task and requires good coordination, dynamic muscle control and flexibility. For adolescents whose coordination and motor control has not fully matured, landing badly from a jump can present a significant risk for injury. There is currently limited biomechanical information regarding the lower limb kinetics of adolescents when jumping, specifically regarding jump kinematics comparing injured with uninjured adolescents. This study reports on an investigation of biomechanical differences in landing patterns of uninjured and injured adolescent basketball players. A matched case-control study design was employed. Twenty-two basketball players aged 14-16 years participated in the study: eleven previously knee-injured and eleven uninjured players matched with cases for age, gender, weight, height and years of play, and playing for the same club. Six high-speed, three-dimensional Vicon 370 cameras (120 Hz), Vicon biomechanical software and SAS Version 8 software were employed to analyse landing patterns when subjects performed a "jump shot". Linear correlations determined functional relationships between the biomechanical performance of lower limb joints, and paired t-tests determined differences between the normalised peak biomechanical parameters. The average peak vertical ground reaction forces between the cases and controls were similar. The average peak ground reaction forces between the cases and controls were moderately correlated (r = -0.47). The control (uninjured) players had significantly greater hip and knee flexion angles and significantly greater eccentric activity on landing than the uninjured cases (p jump, at different ages and physical developmental stages, would assist clinicians and coaches to identify players with inappropriate knee performance comparable to their age or developmental stage.

Procedural Personas for Player Decision Modeling and Procedural Content Generation

DEFF Research Database (Denmark)

Holmgård, Christoffer

2016-01-01

." 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...

Groin Problems in Male Soccer Players Are More Common Than Previously Reported

DEFF Research Database (Denmark)

Harøy, Joar; Clarsen, Ben; Thorborg, Kristian

2017-01-01

surveillance method developed to capture acute and overuse problems. STUDY DESIGN: Descriptive epidemiology study. METHODS: We registered groin problems during a 6-week period of match congestion using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire. A total of 240 players from 15 teams......BACKGROUND: The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus......, the magnitude of groin problems in soccer has probably been underestimated in previous studies based on traditional injury surveillance methods. PURPOSE: To investigate the prevalence of groin problems among soccer players of both sexes and among male soccer players at different levels of play through a new...

Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain

Science.gov (United States)

Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

2014-01-01

Background: Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. Purpose: To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Results: Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Conclusion: Large eccentric hip adduction strength deficits were found in soccer players with adductor-related groin pain

Musculoskeletal injuries among Malaysian badminton players.

Science.gov (United States)

Shariff, A H; George, J; Ramlan, A A

2009-11-01

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.

An Analysis of Creative Process Learning in Computer Game Activities Through Player Experiences

Directory of Open Access Journals (Sweden)

Wilawan Inchamnan

2016-09-01

Full Text Available This research investigates the extent to which creative processes can be fostered through computer gaming. It focuses on creative components in games that have been specifically designed for educational purposes: Digital Game Based Learning (DGBL. A behavior analysis for measuring the creative potential of computer game activities and learning outcomes is described. Creative components were measured by examining task motivation and domain-relevant and creativity-relevant skill factors. The research approach applied heuristic checklists in the field of gameplay to analyze the stage of player activities involved in the performance of the task and to examine player experiences with the Player Experience of Need Satisfaction (PENS survey. Player experiences were influenced by competency, autonomy, intuitive controls, relatedness and presence. This study examines the impact of these activities on the player experience for evaluating learning outcomes through school records. The study is designed to better understand the creative potential of people who are engaged in learning knowledge and skills during the course while playing video games. The findings show the creative potential that occurred to yield levels of creative performance within game play activities to support learning. The anticipated outcome is knowledge on how video games foster creative thinking as an overview of the Creative Potential of Learning Model (CPLN. CPLN clearly describes the interrelationships between principles of learning and creative potential, the interpretation of the results is indispensable.

Interrelationships between measured running intensities and agility performance in subelite rugby union players.

Science.gov (United States)

Jarvis, Stuart; Sullivan, Lee O; Davies, Bruce; Wiltshire, Huw; Baker, Julien S

2009-01-01

The purpose of this study was to investigate agility performance of rugby players using various intensity running tests. A further aim was to investigate if any differences existed between playing positions in relation to agility performance. Nineteen subelite players (mean +/- SD age, 23.0 +/- 5.4 years) participated in the study. Players underwent measurements of anthropometry (height, body mass, and sum of four skinfolds). Running tests investigated were speed (10 m and 40 m sprint), agility (T Test and Illinois), and multistage fitness tests (20 m, 10 m, and 5 m), with all tests for agility measured against the Illinois agility test. Results indicated that backline players produced significant correlations (P rugby-specific agility programs to aid performance may be of greater benefit and of higher priority in training programs designed for backs rather than forwards.

Lumbopelvic motor control and low back pain in elite soccer players: a cross-sectional study.

Science.gov (United States)

Grosdent, Stéphanie; Demoulin, Christophe; Rodriguez de La Cruz, Carlos; Giop, Romain; Tomasella, Marco; Crielaard, Jean-Michel; Vanderthommen, Marc

2016-01-01

This study aimed to investigate the relationship between the history of low back pain and quality of lumbopelvic motor control in soccer players. Forty-three male elite soccer players (mean age, 18.2 ± 1.4 years) filled in questionnaires related to low back pain and attended a session to assess lumbopelvic motor control by means of five tests (the bent knee fall out test, the knee lift abdominal test, the sitting knee extension test, the waiter's bow and the transversus abdominis test). A physiotherapist, blinded to the medical history of the participants, scored (0 = failed, 1 = correct) the performance of the players for each of the tests resulting in a lumbopelvic motor control score ranging from 0 to 5. Forty-seven per cent of the soccer players reported a disabling low back pain episode lasting at least two consecutive days in the previous year. These players scored worse lumbopelvic motor control than players without a history of low back pain (lumbopelvic motor control score of 1.8 vs. 3.3, P soccer players with a history of low back pain had an altered lumbopelvic motor control. Further research should examine whether lumbopelvic motor control is etiologically involved in low back pain episodes in soccer players.

Application of conjoint analysis in studying demand for mp3 players on the B-H market

Directory of Open Access Journals (Sweden)

Emir Kurtović

2008-07-01

Full Text Available The paper illustrates practical aspects of conjoint analysis in studying evaluation and preference criteria when buying hardware MP3 players among the youth, as the most significant segment of such product buyers. Methodology: The methodology consisted of several surveys of young consumers in the Sarajevo region. In the first step, we used unstructured focus group interviews combined with a series of multiple-choice and open-ended questions for identifying product attributes and attribute levels that are relevant to consumers’ preferences. After the main attributes and the levels of attributes had been selected, they were combined to form different hypothetical product profiles. Obtained data were analyzed with the help of the conjoint analysis software. Findings: The results show that MP3 player manufacturers and sellers should focus their marketing strategies on the brand when targeting young people, as the most significant market segment for such products. The findings of the demand and price sensitivity analysis imply that the buyers of this product category are generally price-sensitive and therefore willing to switch brands. Limitations: While the study covered the most important attributes regarding MP3 players, it might be desirable to include design as an additional attribute as well as more brands. Also, a sample size could be increased to allow market segmentation based on the obtained part-worths.

Revising superior planning performance in chess players: the impact of time restriction and motivation aspects.

Science.gov (United States)

Unterrainer, Josef Martin; Kaller, Christoph Philipp; Leonhart, Rainer; Rahm, Benjamin

2011-01-01

In a previous study (Unterrainer, Kaller, Halsband, & Rahm, 2006), chess players outperformed non-chess players in the Tower of London planning task but exhibited disproportionately longer processing times. This pattern of results raises the question of whether chess players' planning capabilities are superior or whether the results reflect differences in the speed-accuracy trade-off between the groups, possibly attributable to sports motivation. The present study was designed to disambiguate these alternative suggestions by implementing various constraints on planning time and by assessing self-reported motivation. In contrast to the previous study, chess players' performance was not superior, independently of whether problems had to be solved with (Experiment 1) or without (Experiment 2) time limits. As expected, chess players reported higher overall trait and state motivation scores across both experiments. These findings revise the notion of superior planning performance in chess players. In consequence, they do not conform with the assumption of a general transfer of chess-related planning expertise to other cognitive domains, instead suggesting that superior performance may be possible only under specific circumstances such as receiving competitive instructions.

Depression in Danish and Swedish elite football players and its relation to perfectionism and anxiety

DEFF Research Database (Denmark)

Jensen, Stine Nylandsted; Ivarsson, Andreas; Fallby, Johan

2018-01-01

Objectives: The aim of this study was to investigate the relation of perfectionism and anxiety to depressive symptoms in Danish and Swedish male elite football players. Additionally, the relationship between age and the study variables, and differences between elite junior and professional players...... were examined. Design and Methods. A cross-sectional design was used to survey 323 A-squad and U19 players (M age = 22.08 years, SD = 5.15). The survey included biographical information as well as measures of depressive symptoms, perfectionism (strivings and concerns), competitive anxiety, and social...... phobia. Results. Results revealed an overall prevalence rate for depressive symptoms among the participants of 16.7%. Moreover, correlation analyses showed evidence of the relationships between depression and perfectionistic concerns, competitive anxiety and social phobia. The results of a mediation...

The posture of adolescent male handball players: A two-year study.

Science.gov (United States)

Grabara, Małgorzata

2018-02-06

Young athletes at the stage of growth acceleration tend to exhibit increased susceptibility to postural abnormalities, especially in the trunk region. The aim of this study was to assess and compare the posture in male adolescent handball players over two years of regular training sessions. The study group comprised 21 handball players. At the start of the study 15 participants were aged 14 and 6 participants were aged 15 (mean 14.25 ± 0.58). The measurements were repeated three times. Posture was assessed with a photogrammetric method based on the moiré phenomenon. The analysis of posture relative to symmetry in the frontal and transverse planes did not reveal any significant differences between posture indicators obtained during the successive measurements. Sagittal plane posture indicators revealed significant changes in torso forward inclination angle and the shape of anteroposterior spinal curvatures. The latter consisted of significant deepening of the upper thoracic curve (angle α) and flattening of the lumbosacral curve (angle γ). A two-year period of handball training did not result in posture asymmetries in young male handball players. The observed changes in the shape of anteroposterior spinal curvatures might be related both to sports training and somatic parameters.

Caffeine Improves Basketball Performance in Experienced Basketball Players

Science.gov (United States)

Puente, Carlos; Areces, Francisco

2017-01-01

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

Comparative characteristics of psychophysiological features skilled basketball players-women with hearing and skilled basketball players healthy

Directory of Open Access Journals (Sweden)

Kozina Zh.L.

2013-06-01

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.

Comparative characteristics of psychophysiological features skilled basketball players-women with hearing and skilled basketball players healthy

Directory of Open Access Journals (Sweden)

Zh.L. Kozina

2013-07-01

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.

Injuries in Portuguese Amateur Youth Football Players: A Six Month Prospective Descriptive Study.

Science.gov (United States)

Nogueira, Miguel; Laiginhas, Rita; Ramos, José; Costa, Ovídio

2017-12-29

This study analyzed the incidence and characteristics of injuries sustained by amateur youth football players in Portugal during season 2015 - 2016. This is an observational descriptive study. We analyzed Portuguese youth football players' injuries over six months of a season. A total of 529 players were divided according to their age in two groups (Under-17 and Under-19). Data on injuries were collected. Throughout all 62 062.0 hours of exposure recorded, 248 injuries were reported in 173 different players. The average incidence of injury was 3.87 (95% CI = 2.81; 4.94) per 1000 hours of football exposure. There was a significantly higher average incidence of injury during matches - 14.22 (95% CI = 10.35; 18.09) per 1000 hours of exposure - when compared to the average incidence of injury during training - 2.06 (95% CI = 1.22; 2.90) per 1000 hours of exposure. This significance was also observed when the comparison was made within each age group. A traumatic mechanism was involved in 76.6% of all the injuries, while overuse was reported in 12.9%. The most common type was the injury that affected muscles and tendons (52.8%). The body location most commonly affected by injuries was the thigh (24.6%). Even though is essential a better characterization of Portuguese athletes of younger age groups such as those discussed in this study, the results of the studied population are in agreement with the existing literature. However, this study provides more information that may be important to better target the Portuguese athletes' training for injury prevention. This study provides descriptive data on injuries developed in a subpopulation of Portuguese amateur youth football players that could represent a focus for future prevention.

Predicting Player Churn In the Wild

DEFF Research Database (Denmark)

Hadiji, Fabian; Sifa, Rafet; Drachen, Anders

2014-01-01

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...

Assessing Cognitive Performance in Badminton Players: A Reproducibility and Validity Study.

Science.gov (United States)

van de Water, Tanja; Huijgen, Barbara; Faber, Irene; Elferink-Gemser, Marije

2017-01-01

Fast reaction and good inhibitory control are associated with elite sports performance. To evaluate the reproducibility and validity of a newly developed Badminton Reaction Inhibition Test (BRIT), fifteen elite (25 ± 4 years) and nine non-elite (24 ± 4 years) Dutch male badminton players participated in the study. The BRIT measured four components: domain-general reaction time, badminton-specific reaction time, domain-general inhibitory control and badminton-specific inhibitory control. Five participants were retested within three weeks on the badminton-specific components. Reproducibility was acceptable for badminton-specific reaction time (ICC = 0.626, CV = 6%) and for badminton-specific inhibitory control (ICC = 0.317, CV = 13%). Good construct validity was shown for badminton-specific reaction time discriminating between elite and non-elite players (F = 6.650, p 0.05). Concurrent validity for domain-general reaction time was good, as it was associated with a national ranking for elite (p = 0.70, p badminton-specific reaction time, nor both components of inhibitory control (p > 0.05). In conclusion, reproducibility and validity of inhibitory control assessment was not confirmed, however, the BRIT appears a reproducible and valid measure of reaction time in badminton players. Reaction time measured with the BRIT may provide input for training programs aiming to improve badminton players' performance.

[The relevance of core muscles in ice hockey players: a feasibility study].

Science.gov (United States)

Rogan, S; Blasimann, A; Nyffenegger, D; Zimmerli, N; Radlinger, L

2013-12-01

Good core strength is seen as a condition for high performance in sports. In general, especially maximum voluntary contraction (MVC) and strength endurance (SE) measurements of the core muscles are used. In addition, a few studies can be found that examine the core muscles in terms of MVC, rate of force development (RFD) and SE. Primary aims of this feasibility study were to investigate the feasibility regarding recruiting process, compliance and safety of the testing conditions and raise the force capabilities MVC, RFD and SE of the core muscles in amateur ice hockey players. Secondarily, tendencies of correlations between muscle activity and either shot speed and sprint time shall be examined. In this feasibility study the recruitment process has been approved by 29 ice hockey players, their adherence to the study measurements of trunk muscles, and safety of the measurements was evaluated. To determine the MVC, RFD and SE for the ventral, lateral and dorsal core muscles a dynamic force measurement was performed. To determine the correlation between core muscles and shot speed and 40-m sprint, respectively, the rank correlation coefficient (rho) from Spearman was used. The recruited number of eight field players and one goal-keeper was not very high. The compliance with 100 % was excellent. The players reported no adverse symptoms or injuries after the measurements. The results show median values for the ventral core muscles for MVC with 46.5 kg for RFD with 2.23 m/s2 and 96 s for the SE. For lateral core muscle median values of the lateral core muscles for MVC with 71.10 kg, RFD with 2.59 m/s2 and for SE over 66 s were determined. The dorsal core muscles shows values for MVC 69.7 kg, for RFD 3.39 m/s2 and for SE of 75 s. High correlations between MVC of the ventral core muscles (rho = -0.721, p = 0.021), and between the SE of the ventral core muscles (rho = 0.787, p = 0.012), and the shot velocity rate were determined. Another

Vitamin D Deficiency Among Professional Basketball Players.

Science.gov (United States)

Fishman, Matthew P; Lombardo, Stephen J; Kharrazi, F Daniel

2016-07-01

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

Nutrient Intake and Food Habits of Soccer Players: Analyzing the Correlates of Eating Practice

Science.gov (United States)

García-Rovés, Pablo M.; García-Zapico, Pedro; Patterson, Ángeles M.; Iglesias-Gutiérrez, Eduardo

2014-01-01

Despite the impact and popularity of soccer, and the growing field of soccer-related scientific research, little attention has been devoted to the nutritional intake and eating habits of soccer players. Moreover, the few studies that have addressed this issue suggest that the nutritional intake of soccer players is inadequate, underscoring the need for better adherence to nutritional recommendations and the development and implementation of nutrition education programs. The objective of these programs would be to promote healthy eating habits for male and female soccer players of all ages to optimize performance and provide health benefits that last beyond the end of a player’s career. To date, no well-designed nutrition education program has been implemented for soccer players. The design and implementation of such an intervention requires a priori knowledge of nutritional intake and other correlates of food selection, such as food preferences and the influence of field position on nutrient intake, as well as detailed analysis of nutritional intake on match days, on which little data is available. Our aim is to provide an up-to-date overview of the nutritional intake, eating habits, and correlates of eating practice of soccer players. PMID:25045939

Nutrient Intake and Food Habits of Soccer Players: Analyzing the Correlates of Eating Practice

Directory of Open Access Journals (Sweden)

Pablo M. García-Rovés

2014-07-01

Full Text Available Despite the impact and popularity of soccer, and the growing field of soccer-related scientific research, little attention has been devoted to the nutritional intake and eating habits of soccer players. Moreover, the few studies that have addressed this issue suggest that the nutritional intake of soccer players is inadequate, underscoring the need for better adherence to nutritional recommendations and the development and implementation of nutrition education programs. The objective of these programs would be to promote healthy eating habits for male and female soccer players of all ages to optimize performance and provide health benefits that last beyond the end of a player’s career. To date, no well-designed nutrition education program has been implemented for soccer players. The design and implementation of such an intervention requires a priori knowledge of nutritional intake and other correlates of food selection, such as food preferences and the influence of field position on nutrient intake, as well as detailed analysis of nutritional intake on match days, on which little data is available. Our aim is to provide an up-to-date overview of the nutritional intake, eating habits, and correlates of eating practice of soccer players.

A Study of Interaction Patterns and Awareness Design Elements in a Massively Multiplayer Online Game

Directory of Open Access Journals (Sweden)

Tiffany Y. Tang

2008-01-01

Full Text Available Massively multiplayer online games (MMOGs have been known to create rich and versatile social worlds for thousands of millions of players to participate. As such, various game elements and advance technologies such as artificial intelligence have been applied to encourage and facilitate social interactions in these online communities, the key to the success of MMOGs. However, there is a lack of studies addressing the usability of these elements in games. In this paper, we look into interaction patterns and awareness design elements that support the awareness in LastWorld and FairyLand. Experimental results obtained through both in-game experiences and player interviews reveal that not all awareness tools (e.g., an in-game map have been fully exploited by players. In addition, those players who are aware of these tools are not satisfied with them. Our findings suggest that awareness-oriented tools/channels should be easy to interpret and rich in conveying “knowledge” so as to reduce players-cognitive overload. These findings of this research recommend considerations of early stage MMOG design.

Differences in injury risk and characteristics between Dutch amateur and professional soccer players

NARCIS (Netherlands)

Anne-Marie van Beijsterveldt, A. M C; Stubbe, J. H.; Schmikli, S. L.; Van De Port, I. G L; Backx, F. J G

2015-01-01

Objectives To compare the incidence and characteristics of injuries between Dutch amateur and professional male soccer players during one entire competition season. Design A prospective two-cohort design. Methods During the 2009–2010 season, 456 Dutch male amateur soccer players and 217 professional

Video-based multimedia designs: A research study testing learning effectiveness

Directory of Open Access Journals (Sweden)

David Reiss

2008-05-01

Full Text Available This paper summarizes research conducted on three computer-based video models’ effectiveness for learning based on memory and comprehension. In this quantitative study, a two-minute video presentation was created and played back in three different types of media players, for a sample of eighty-seven college freshman. The three players evaluated include a standard QuickTime video/audio player, a QuickTime player with embedded triggers that launched HTML-based study guide pages, and a Macromedia Flash-based video/audio player with a text field, with user activated links to the study guides as well as other interactive on-line resources. An assumption guiding this study was that the enhanced designs presenting different types of related information would reinforce the material and produce better comprehension and retention. However, findings indicate that the standard video player was the most effective overall, which suggests that media designs able to control the focus of a learner’s attention to one specific stream of information, a single-stream focused approach, may be the most effective way to present media-based content. Résumé: Cet article résume une étude vérifiant l’efficacité de l’apprentissage basé sur la mémorisation et la compréhension, conduite à partir de trois modèles basés sur la vidéo informatisée. Dans cette étude quantitative, une vidéo de deux minutes a été créée et lue sur trois types de lecteurs différents, pour un échantillon de 87 étudiants universitaires de première année. Les trois lecteurs évalués comprenaient un lecteur standard audio/vidéo Quicktime, un lecteur Quicktime avec déclencheurs intégrés qui lançait un guide d’étude en HTML, et un lecteur audio/vidéo Flash Macromedia avec un champ texte, comprenant des liens activés par l’usager vers des guides d’étude et d’autres ressources interactives en ligne. Une supposition guidant cette étude était que les designs

Vascular Health in American Football Players: Cardiovascular Risk Increased in Division III Players

Directory of Open Access Journals (Sweden)

Deborah L. Feairheller

2016-01-01

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.

Towards Player-Driven Procedural Content Generation

DEFF Research Database (Denmark)

Shaker, Noor

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...

Small-sided game training improves aerobic capacity and technical skills in basketball players.

Science.gov (United States)

Delextrat, A; Martinez, A

2014-05-01

The aim of this study was to compare the effects of 2 training interventions based on small-sided games (SGG) and high-intensity interval training (HIT) on physical and technical performance of male junior basketball players. A secondary objective was to investigate if these effects were similar in starting and bench players. 18 players participated in a pre-testing session, 6-weeks intervention period and a post-testing session. Pre- and post-sessions involved assessments of aerobic fitness, repeated sprint ability (RSA), defensive and offensive agility, upper and lower body power, shooting and passing skills. Mixed-design analysis of variance (ANOVA) with Bonferroni corrected pairwise comparisons examined the effects of time and type of intervention on physical and technical performances. The main results showed that both interventions resulted in similar improvements in aerobic capacity (+3.4% vs. +4.1%), with greater improvements in bench players compared to starting players (+7.1% vs. +1.1%, Pbasketball players during the season. However, when RSA is targeted, more specific training seems necessary. © Georg Thieme Verlag KG Stuttgart · New York.

EFFECT OF A TRAINING PROGRAM ON THE IMPROVEMENT OF BASKETBALL PLAYERS' DECISION MAKING

Directory of Open Access Journals (Sweden)

Francisco Alarc\\u00F3n

2009-01-01

Full Text Available The aim of this study was to analyse whether a tactical training program based on a constructivist model can improve decision making related to keeping control of the ball for a men's senior basketball team composed of ten players. The dependent variables were: player distribution around the ball, and achieving support on both sides of the ball at an effective passing distance. Data collection was made through observational analysis utilizing a previously validated tool. A pretest-posttest design without a control group was used. Results demonstrated an improvement in decision making after the posttest for both the number of support players near the player with the ball, as it increased from 85% in the pretest to 100% in the posttest, and the number of collective or team actions around the player with the ball (from 5% to 76.5% with highly significant differences. The primary conclusion is that a training program for teaching team tactics based on a constructivist model has a positive influence on players' capability to facilitate the pass to their teammates.

Rules of engagement : influence of co-player presence on player involvement in digital games

NARCIS (Netherlands)

Gajadhar, B.J.; Kort, de Y.A.W.; IJsselsteijn, W.A.

2009-01-01

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,

Finite stage asymmetric repeated games: Both players' viewpoints

KAUST Repository

Li, Lichun

2017-01-05

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.

The things we learned on Liberty Island: designing games to help people become competent game players

OpenAIRE

Pelletier, Caroline

2005-01-01

Although interest in the use of games to support education is growing (e.g. Dawes & Dumbleton, 2001; McFarlane et al, 2002; Mitchell & Savill-Smith, 2004), there is relatively little research into how people learn to play games. This is surprising, since VanDeventer and White (2002) have demonstrated that game players demonstrate characteristics of expert behaviour and Gee (2003) argues that highly successful implicit theories of learning are embedded in well-designed games. In spite ...

Strength and Jump Biomechanics of Elite and Recreational Female Youth Soccer Players

Science.gov (United States)

Chrisman, Sara P.; O'Kane, John W.; Polissar, Nayak L.; Tencer, Allan F.; Mack, Christopher D.; Levy, Marni R.; Schiff, Melissa A.

2012-01-01

Context Most researchers investigating soccer injuries have studied elite athletes because they have greater athletic-exposure hours than other athletes, but most youth participate at the recreational level. If risk factors for injury vary by soccer level, then recommendations generated using research with elite youth soccer players might not generalize to recreational players. Objective To examine injury risk factors of strength and jump biomechanics by soccer level in female youth athletes and to determine whether research recommendations based on elite youth athletes could be generalized to recreational players. Design Cross-sectional study. Setting Seattle Youth Soccer Association. Patients or Other Participants Female soccer players (N = 92) aged 11 to 14 years were recruited from 4 randomly selected elite (n = 50; age = 12.5 years, 95% confidence interval [95% CI]) = 12.3, 12.8 years; height = 157.8 cm, 95% CI = 155.2, 160.3 cm; mass = 49.9 kg, 95% CI = 47.3, 52.6 kg) and 4 randomly selected recreational (n = 42; age = 13.2 years, 95% CI = 13.0, 13.5 years; height = 161.1 cm, 95% CI = 159.2, 163.1 cm; mass = 50.6 kg, 95% CI = 48.3, 53.0 kg) soccer teams. Main Outcome Measure(s) Players completed a questionnaire about demographics, history of previous injury, and soccer experience. Physical therapists used dynamometry to measure hip strength (abduction, adduction, extension, flexion) and knee strength (flexion, extension) and Sportsmetrics to measure vertical jump height and jump biomechanics. We compared all measurements by soccer level using linear regression to adjust for age and mass. Results Elite players were similar to recreational players in all measures of hip and knee strength, vertical jump height, and normalized knee separation (a valgus estimate generated using Sportsmetrics). Conclusions Female elite youth players and recreational players had similar lower extremity strength and jump biomechanics. This suggests that recommendations generated from

Study on the use of types of shots in Valencian Handball on professional players

Directory of Open Access Journals (Sweden)

José Antonio Martínez Carbonell

2013-01-01

Full Text Available Due to the shortage of studies of analysis in Valencian ball, we have centred this study on this sport. The aim of study has been to analyze and to quantify the types of shots , and to compare the same ones between the positions of game of 1st game line (resto and 2nd game line (medio. Analysis of 6 games of the 19th Professional League of Stand and rope 2009-2010 was carried out so i, and specifically of 12 players, using Sports Code analysis software. The results indicate significant differences (p<0.05 between the shots carried out by first game line player and second game line in the rebound and rebound-shot all of them of right and left hand,and stand shot right hand; being almost realitzados only by players from the first game line position. At the same time we find data which demonstrate us by another band used mainly by second game line players beatings, these have been volley shot, volley shot after bounce, volley shot under the line of the shoulders, palm shot and horizontal shot all of them of right hand. As conclusion of the study, we have obtained that depending on the position of game the players use a few types of I throb or others. Therefore, we affirm, that the analysis of the high performance in stand and rope from the advances of the technologies, a valuable information contributes us to establish specific bosses of training.

The Diagnostic and Prognostic Value of Ultrasonography in Soccer Players With Acute Hamstring Injuries

DEFF Research Database (Denmark)

Petersen, Jesper; Thorborg, Kristian; Nielsen, Michael Bachmann

2014-01-01

BACKGROUND: An injury to the hamstring muscle complex is the most common injury in soccer. Ultrasound of acute hamstring injuries is often used as a clinical tool for diagnosing hamstring injuries and guiding players in when they can return to play. PURPOSE: To (1) investigate the characteristic......) to investigate if ultrasonography can be used as a prognostic indicator of time to return to play. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Players from 50 teams participating in 1 of the top 5 Danish soccer divisions were followed in the period from January to December 2008. Of 67 players...

Shoulder instability in professional football players.

Science.gov (United States)

Leclere, Lance E; Asnis, Peter D; Griffith, Matthew H; Granito, David; Berkson, Eric M; Gill, Thomas J

2013-09-01

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.

The audiological health of horn players.

Science.gov (United States)

Wilson, Wayne J; O'Brien, Ian; Bradley, Andrew P

2013-01-01

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.

HIP AND GLENOHUMERAL PASSIVE RANGE OF MOTION IN COLLEGIATE SOFTBALL PLAYERS

Science.gov (United States)

Plummer, Hillary; Brambeck, Allison

2016-01-01

Background and Purpose Range of motion deficits at the hip and glenohumeral joint (GHJ) may contribute to the incidence of injury in softball players. With injury in softball players on the rise, softball related studies in the literature are important. The purpose of this study was to examine hip and GHJ passive range of motion (PROM) patterns in collegiate softball players. Hypothesis It was hypothesized that the position players would exhibit significantly different PROM patterns than pitchers. Additionally, position players would exhibit significantly different side-to-side differences in PROM for both the hip and GHJ compared to pitchers. Study Design Prospective cohort study. Methods Forty-nine collegiate softball players (19.63 ± 1.15 years; 170.88 ± 8.08 cm; 72.96 ± 19.41 kg) participated. Passive hip and GHJ internal (IR) and external rotation (ER) measures were assessed. Glenohumeral PROM was measured with the participants supine with the arm abducted to 90 °. The measurements were recorded when the scapula began to move or a firm capsular end-feel was achieved. The hip was positioned in 90 ° of flexion and passively rotated until a capsular end-feel was achieved. Total PROM was calculated by taking the sum of IR and ER for both the hip and GHJ. Results No significant side-to-side PROM differences were observed in pitchers, at the GHJ or hip joint. Position players throwing side hip IR was significantly greater than the non-throwing side hip (p = 0.002). The non-throwing side hip had significantly greater ER compared to the throwing side hip (p = 0.002). When examining side-to-side differences at the GHJ, IR was significantly greater in the non-throwing shoulder (p = 0.047). No significant differences in total range of motion of the hip and GHJ were observed. Conclusion In the current study, position players displayed side-to-side differences in hip and GHJ IR PROM while no statistically significant differences were

Player Characteristics and Games: Findings and Implications for Distance Learning

Science.gov (United States)

Marvel, Michele D.

2017-01-01

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…

The relationship between avatar's capital and player's gaming orientation : a study in Final Fantasy XIV

OpenAIRE

Korkeila, Henry

2017-01-01

The world's digitalization has changed our lives in numerous ways. Digitalization has changed how people consume entertainment and video games are just one example of this. Persistent online game worlds where a massive number of players can interact with each other around the clock were non-existent two decades ago. Player studies is still in its infancy, because it is not fully understood yet what kind of lives the players have in these online virtual worlds. One way to look at the lives of ...

Physical Attributes and NFL Combine Performance Tests Between Italian National League and American Football Players: A Comparative Study.

Science.gov (United States)

Vitale, Jacopo A; Caumo, Andrea; Roveda, Eliana; Montaruli, Angela; La Torre, Antonio; Battaglini, Claudio L; Carandente, Franca

2016-10-01

Vitale, JA, Caumo, A, Roveda, E, Montaruli, A, La Torre, A, Battaglini, CL, and Carandente, F. Physical attributes and NFL Combine performance tests between Italian National League and American football players: a comparative study. J Strength Cond Res 30(10): 2802-2808, 2016-The purpose of this study was to examine anthropometric measurements and the results of a battery of performance tests administered during the National Football League (NFL) Combine between American football players who were declared eligible to participate in the NFL Combine and football players of a top Italian team (Rhinos Milan). Participants (N = 50) were categorized by position into 1 of 3 groups based on playing position: skill players (SP) included wide receivers, cornerbacks, free safeties, strong safeties, and running backs; big skill players (BSP) consisted of fullbacks, linebackers, tight ends, and defensive ends; lineman (LM) included centers, offensive guards, offensive tackles, and defensive tackles. A 1-way analysis of variance followed by the Tukey-Kramer post hoc test was used for comparisons between Italian players by playing position. Ninety-five percent CIs were used for comparisons between American and Italian football for the NFL Combine performance tests. Significant differences for all the variables between the 3 playing categories were observed among the Italian players; LM had higher anthropometric and body composition values than SP (p football players presented significantly higher anthropometric values and test performance scores when compared with Italian players. Administrators of professional football teams in Italy need to improve the player's physical attributes, so the gap that currently exists between American and Italian players can be reduced, which could significantly improve the quality of American football in Italy.

Player Skill Decomposition in Multiplayer Online Battle Arenas

OpenAIRE

Chen, Zhengxing; Sun, Yizhou; El-nasr, Magy Seif; Nguyen, Truong-Huy D.

2017-01-01

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...

Multiple Past Concussions in High School Football Players

Science.gov (United States)

Brooks, Brian L.; Mannix, Rebekah; Maxwell, Bruce; Zafonte, Ross; Berkner, Paul D.; Iverson, Grant L.

2017-01-01

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

Vulnerability Analysis of the Player Command and Control Protocol

Science.gov (United States)

2012-06-14

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

Hand Grip Strength Vs. Sprint Effectiveness in Amputee Soccer Players.

Science.gov (United States)

Wieczorek, Marta; Wiliński, Wojciech; Struzik, Artur; Rokita, Andrzej

2015-11-22

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.

Hand Grip Strength Vs. Sprint Effectiveness in Amputee Soccer Players

Directory of Open Access Journals (Sweden)

Wieczorek Marta

2015-12-01

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.

Lateral Scapular Slide Test and Scapular Mobility in Volleyball Players

Science.gov (United States)

Ozunlu, Nihan; Tekeli, Hatice; Baltaci, Gul

2011-01-01

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

Comparison of Shoulder Strength in Routinely Trained Badminton Players and Non-Badminton Players

Directory of Open Access Journals (Sweden)

Wong Zhen Feng

2017-06-01

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

The Prevalence of Injuries in Professional Turkish Soccer Players

Science.gov (United States)

Yamaner, Faruk; Gumusdag, Hayrettin; Kartal, Alparslan; Gumus, M.; Gullu, A.; Imamoglu, O.

2011-01-01

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…

Time-motion analysis of goalball players in attacks: differences of the player positions and the throwing techniques.

Science.gov (United States)

Monezi, Lucas Antônio; Magalhães, Thiago Pinguelli; Morato, Márcio Pereira; Mercadante, Luciano Allegretti; Furtado, Otávio Luis Piva da Cunha; Misuta, Milton Shoiti

2018-03-26

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.

Dynamic balance performance and noncontact lower extremity injury in college football players: an initial study.

Science.gov (United States)

Butler, Robert J; Lehr, Michael E; Fink, Michael L; Kiesel, Kyle B; Plisky, Phillip J

2013-09-01

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. To determine if dynamic balance deficits are associated with an elevated risk of injury in collegiate football players. It was hypothesized that football players with lower performance and increased asymmetry in dynamic balance would be at an elevated risk for sustaining a noncontact lower extremity injury. Prospective cohort study. Fifty-nine collegiate American football players volunteered for this study. Demographic information, injury history, and dynamic balance testing performance were collected, and noncontact lower extremity injuries were recorded over the course of the season. Receiver operator characteristic curves were calculated based on performance on the Star Excursion Balance Test (SEBT), including composite score and asymmetry, to determine the population-specific risk cut-off point. Relative risk was then calculated based on these variables, as well as previous injury. A cut-off point of 89.6% composite score on the SEBT optimized the sensitivity (100%) and specificity (71.7%). A college football player who scored below 89.6% was 3.5 times more likely to get injured. Poor performance on the SEBT may be related to an increased risk for sustaining a noncontact lower extremity injury over the course of a competitive American football season. College football players should be screened preseason using the SEBT to identify those at an elevated risk for injury based upon dynamic balance performance to implement injury mitigation strategies to this specific subgroup of athletes.

A cross-genre study of online gaming: player demographics, motivation for play, and social interactions among players

OpenAIRE

Ghuman, D; Griffiths, MD

2012-01-01

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...

Intrinsic risk factors of noncontact ankle sprains in soccer: a prospective study on 100 professional players.

Science.gov (United States)

Fousekis, Konstantinos; Tsepis, Elias; Vagenas, George

2012-08-01

Ankle sprain is an extremely common injury in soccer players. Despite extensive research, the intrinsic cause of this injury under noncontact conditions remains unclear. To identify intrinsic risk factors for noncontact ankle sprains in professional soccer players. Cohort study; Level of evidence, 2 One hundred professional soccer players were assessed in the preseason for potential risk factors of noncontact ankle sprains. The assessment included (A) ankle joint asymmetries (right-left) in isokinetic muscle strength, flexibility, proprioception, and stability; (B) somatometric asymmetries; (C) previous injuries; and (D) lateral dominance traits. Noncontact ankle sprains were prospectively recorded and diagnosed for a full competition period (10 months). Seventeen of the players sustained at least 1 noncontact ankle sprain. Logistic regression revealed that players with (A) eccentric isokinetic ankle flexion strength asymmetries (odds ratio [OR] = 8.88; 95% confidence interval [CI], 1.95-40.36, P = .005), (B) increased body mass index (OR = 8.16; 95% CI, 1.42-46.63, P = .018), and (C) increased body weight (OR = 5.72; 95% CI, 1.37-23.95, P = .017 ) each had a significantly higher risk of a noncontact ankle sprain. A trend for younger players (OR = 0.28; 95% CI, 0.061-1.24, P = .092) and for players with ankle laxity asymmetries (OR = 3.38; 95% CI, 0.82-14.00, P = .093) to be at greater risk for ankle sprain was also apparent to the limit of statistical significance (.05 ankle flexors and increased body mass index and body weight raise the propensity for ankle sprains in professional soccer players. Age and asymmetries in ankle laxity are potential factors worth revisiting, as there was an indication for younger players and players with ankle instability to be at higher risk for ankle injury. Proper preseason evaluation may improve prevention strategies for this type of injury in soccer.

Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain An Assessor-Blinded Comparison

DEFF Research Database (Denmark)

Thorborg, Kristian; Branci, Sonia; Nielsen, Peter Martin

2014-01-01

BACKGROUND: Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been...... investigated. PURPOSE: To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction...... strength than players without adductor-related groin pain. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain...

Concussion Education for High School Football Players: A Pilot Study

Science.gov (United States)

Manasse-Cohick, Nancy J.; Shapley, Kathy L.

2014-01-01

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)…

Bone geometry in young male and female football players: a peripheral quantitative computed tomography (pQCT) study.

Science.gov (United States)

Lozano-Berges, Gabriel; Matute-Llorente, Ángel; Gómez-Bruton, Alejandro; González-Agüero, Alex; Vicente-Rodríguez, Germán; Casajús, José A

2018-05-08

The present study shows that football practice during growth may improve bone geometry in male and female football players. However, only females had better bone strength in comparison with controls. The aim of this study was to compare bone geometry in adolescent football players and controls. A total of 107 football players (71 males/36 females; mean age 12.7 ± 0.6/12.7 ± 0.6 years) and 42 controls (20 males/22 females; mean age 13.1 ± 1.4/12.7 ± 1.3 years) participated in this study. Total and trabecular volumetric bone mineral content (Tt.BMC/Tb.BMC), cross-sectional area (Tt.Ar/Tb.Ar), and bone strength index (BSI) were measured at 4% site of the non-dominant tibia by peripheral quantitative computed tomography (pQCT). Moreover, Tt.BMC, cortical BMC (Ct.BMC), Tt.Ar, cortical Ar (Ct.Ar), cortical thickness (Ct.Th), periosteal circumference (PC), endosteal circumference (EC), fracture load in X-axis, and polar strength strain index (SSIp) were measured at 38% site of the tibia. Multivariate analyses of covariance were used to compare bone pQCT variables between football players and controls using the tibia length and maturity offset as covariates. Female football players demonstrated 13.8-16.4% higher BSI, Ct.Th, fracture load in X-axis, and SSIp than controls (p  .0036). In relation to bone mineral content and area, male football players showed 8.8% higher Tt.Ar and Tb.Ar at the 4% site of the tibia when compared to controls; whereas 13.8-15.8% higher Tt.BMC, Ct.BMC, and Ct.Ar at the 38% site of the tibia were found in female football players than controls (p female adolescent football players presented better bone geometry and strength values than controls. In contrast, only bone geometry was higher in male football players than controls.

Comparative cervical profiles of adult and under-18 front-row rugby players: implications for playing policy

Science.gov (United States)

Hamilton, D F; Gatherer, D; Robson, J; Graham, N; Rennie, N; MacLean, J G B; Simpson, A H R W

2014-01-01

Objective To compare the cervical isometric strength, fatigue endurance and range of motion of adult and under-18 age-grade front-row rugby players to inform the development of a safe age group policy with particular reference to scrummaging. Design Cross-sectional cohort study. Setting ‘Field testing’ at Murrayfield stadium. Participants 30 high-performance under-18 players and 22 adult front-row rugby players. Outcome measures Isometric neck strength, height, weight and grip strength. Results Youth players demonstrated the same height and grip strength as the adult players; however, the adults were significantly heavier and demonstrated substantially greater isometric strength (prugby players demonstrate the same peripheral strength as their adult counterparts on grip testing, the adults demonstrate significantly greater cervical strength. If older youths and adults are to play together, such findings have to be noted in the development of age group policies with particular reference to the scrum. PMID:24797427

Risk factors for patellar tendinopathy in basketball and volleyball players: a cross-sectional study.

Science.gov (United States)

van der Worp, H; van Ark, M; Zwerver, J; van den Akker-Scheek, I

2012-12-01

Patellar tendinopathy (PT) has a multifactorial etiology, and many possible risk factors have been described in the literature. The findings are conflicting, though, and most research has been conducted on elite athletes. The aim of the current study is to determine the risk factors for PT in a large representative sample of basketball and volleyball players. Separate risk factors for men and women, basketball and volleyball players, and athletes with unilateral and bilateral PT were identified. All basketball and volleyball players between ages 18 and 35 from the Dutch Basketball Association and the Dutch Volleyball Association were invited to complete an online questionnaire on knee complaints and risk factors for PT. The logistic regression analyses included 2224 subjects. The risk factors for PT were age, playing at the national level, being male and playing volleyball (compared with playing basketball). The risk factors for men and women were comparable. Among volleyball players, outside hitters and middle blockers/hitters had an increased risk compared with setters. For basketball players, no risk factors could be identified. No differences in the risk factors were found between athletes with unilateral and bilateral PT. These findings should be taken into account for prevention and rehabilitation purposes. © 2011 John Wiley & Sons A/S.

Analysis of Injury Incidences in Male Professional Adult and Elite Youth Soccer Players: A Systematic Review.

Science.gov (United States)

Pfirrmann, Daniel; Herbst, Mark; Ingelfinger, Patrick; Simon, Perikles; Tug, Suzan

2016-05-01

The incidence of injury for elite youth and professional adult soccer players is an important concern, but the risk factors for these groups are different. To summarize and compare the injury incidences and injury characteristics of male professional adult and elite youth soccer players. We searched MEDLINE and Web of Science using the search terms elite, international, European, soccer, football, injury, injuries, epidemiology, incidence, prevalence, not female, not American football, and not rugby. We also used the search terms professional for studies on professional adult soccer players and high-level, soccer academy, youth, adolescent, and young for studies on elite youth soccer players. Eligible studies were published in English, had a prospective cohort design, and had a minimum study period of 6 months. To ensure that injury data were assessed in relationship to the athlete's individual exposure, we included only studies that reported on injuries and documented exposure volume. Two independent reviewers applied the selection criteria and assessed the quality of the studies. A total of 676 studies were retrieved from the literature search. Eighteen articles met the inclusion criteria: 6 for elite youth and 12 for professional adult soccer players. Injury rates were higher for matches than for training for both youth and adult players. Youth players had a higher incidence of training injuries than professionals. Efforts must be made to reduce the overall injury rate in matches. Therefore, preventive interventions, such as adequately enforcing rules and focusing on fair play, must be analyzed and developed to reduce match-related injury incidences. Reducing training injuries should be a particular focus for youth soccer players.

An embouchure aid for saxophone player

Directory of Open Access Journals (Sweden)

Ho-Jin Moon

2012-02-01

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.

Comparison of Angiotensin Converting Enzyme (ACE gene polymorphisms elite basketball players and volleyball players

Directory of Open Access Journals (Sweden)

Emin Süel

2015-09-01

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.

Training Patterns of Wheelchair Basketball Players in Turkey

Science.gov (United States)

Tatar, Yasar

2008-01-01

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…

Previously identified patellar tendinopathy risk factors differ between elite and sub-elite volleyball players.

Science.gov (United States)

Janssen, I; Steele, J R; Munro, B J; Brown, N A T

2015-06-01

Patellar tendinopathy is the most common knee injury incurred in volleyball, with its prevalence in elite athletes more than three times that of their sub-elite counterparts. The purpose of this study was to determine whether patellar tendinopathy risk factors differed between elite and sub-elite male volleyball players. Nine elite and nine sub-elite male volleyball players performed a lateral stop-jump block movement. Maximum vertical jump, training history, muscle extensibility and strength, three-dimensional landing kinematics (250 Hz), along with lower limb neuromuscular activation patterns (1500 Hz), and patellar tendon loading were collected during each trial. Multivariate analyses of variance (P volleyball players. Interventions designed to reduce landing frequency and improve quadriceps extensibility are recommended to reduce patellar tendinopathy prevalence in volleyball players. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cognitive Functions in Elite and Sub-Elite Youth Soccer Players Aged 13 to 17 Years.

Directory of Open Access Journals (Sweden)

Barbara C H Huijgen

Full Text Available Soccer players are required to anticipate and react continuously in a changing, relatively unpredictable situation in the field. Cognitive functions might be important to be successful in soccer. The current study investigated the relationship between cognitive functions and performance level in elite and sub-elite youth soccer players aged 13-17 years. A total of 47 elite youth soccer players (mean age 15.5 years, SD = 0.9 and 41 sub-elite youth soccer players (mean age 15.2 years, SD = 1.2 performed tasks for "higher-level" cognitive functions measuring working memory (i.e., Visual Memory Span, inhibitory control (i.e., Stop-Signal Task, cognitive flexibility (i.e., Trail Making Test, and metacognition (i.e., Delis-Kaplan Executive Function System Design Fluency Test. "Lower-level" cognitive processes, i.e., reaction time and visuo-perceptual abilities, were also measured with the previous tasks. ANOVA's showed that elite players outscored sub-elite players at the "higher-level" cognitive tasks only, especially on metacognition (p .05. In conclusion, elite youth soccer players have better inhibitory control, cognitive flexibility, and especially metacognition than their sub-elite counterparts. However, when training hours are taken into account, differences between elite and sub-elite youth soccer players remain apparent on inhibitory control and cognitive flexibility in contrast to metacognition. This highlights the need for longitudinal studies to further investigate the importance of "higher-level" cognitive functions for talent identification, talent development and performance in soccer.

Cognitive Functions in Elite and Sub-Elite Youth Soccer Players Aged 13 to 17 Years

Science.gov (United States)

Huijgen, Barbara C. H.; Leemhuis, Sander; Kok, Niels M.; Verburgh, Lot; Oosterlaan, Jaap; Elferink-Gemser, Marije T.; Visscher, Chris

2015-01-01

Soccer players are required to anticipate and react continuously in a changing, relatively unpredictable situation in the field. Cognitive functions might be important to be successful in soccer. The current study investigated the relationship between cognitive functions and performance level in elite and sub-elite youth soccer players aged 13–17 years. A total of 47 elite youth soccer players (mean age 15.5 years, SD = 0.9) and 41 sub-elite youth soccer players (mean age 15.2 years, SD = 1.2) performed tasks for “higher-level” cognitive functions measuring working memory (i.e., Visual Memory Span), inhibitory control (i.e., Stop-Signal Task), cognitive flexibility (i.e., Trail Making Test), and metacognition (i.e., Delis-Kaplan Executive Function System Design Fluency Test). “Lower-level” cognitive processes, i.e., reaction time and visuo-perceptual abilities, were also measured with the previous tasks. ANOVA’s showed that elite players outscored sub-elite players at the “higher-level” cognitive tasks only, especially on metacognition (p .05). In conclusion, elite youth soccer players have better inhibitory control, cognitive flexibility, and especially metacognition than their sub-elite counterparts. However, when training hours are taken into account, differences between elite and sub-elite youth soccer players remain apparent on inhibitory control and cognitive flexibility in contrast to metacognition. This highlights the need for longitudinal studies to further investigate the importance of “higher-level” cognitive functions for talent identification, talent development and performance in soccer. PMID:26657073

Prevalence of Musculoskeletal Injuries in Shiraz Male Wushu Players: A Cross Sectional Study

Directory of Open Access Journals (Sweden)

Farahnaz Emami

2017-03-01

Full Text Available Background: Wushu is one of the martial arts that combines explosive strength and speed movements with combat techniques. Most studies to date of wushurelated injuries have been published in Chinese languages. No published studies have reported the prevalence of these injuries in Iran. Therefore, the aim of the present study was to determine the prevalence of musculoskeletal injuries in male wushu players in Shiraz. Methods: Male wushu athletes aged 18 to 30 years were included in this cross sectional study if they had been practicing for 2 hours per session, twice a week during the past 3 years. The athletes were recruited by convenience sampling from 30 wushu clubs in Shiraz, Iran. The sample size was 165. The study was conducted from June to September 2016. Each participant was asked to complete an information questionnaire about his musculoskeletal injuries related to wushu during the previous year. Results: About two third (65.45% of wushu players had one or more injuries during the previous year. Severe injuries were most commonly located in the head/neck and knee/tibia areas, and inflammation was more prevalent than the other types of injuries. Conclusion: Wushu players in this study reported a high prevalence of injuries affecting different parts of the body.

A Longitudinal Study of Physical Fitness in Elite Junior Tennis Players

NARCIS (Netherlands)

Kramer, Tamara; Huijgen, Barbara C. H.; Elferink-Gemser, Marije T.; Visscher, Chris

Purpose: To analyze how physical fitness (PF) improves in elite junior tennis players related to age, maturity, and performance level. Methods: Elite junior tennis players (n = 113 boys, n = 83 girls) divided by performance level were monitored longitudinally from U14 to U16. Maturity, upper and

Outcomes of microfracture in professional basketball players.

Science.gov (United States)

Cerynik, Douglas L; Lewullis, Gabriel E; Joves, Brian C; Palmer, Michael P; Tom, James A

2009-09-01

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.

A new physical performance classification system for elite handball players: cluster analysis

Science.gov (United States)

Chirosa, Ignacio J.; Robinson, Joseph E.; van der Tillaar, Roland; Chirosa, Luis J.; Martín, Isidoro Martínez

2016-01-01

Abstract The aim of the present study was to identify different cluster groups of handball players according to their physical performance level assessed in a series of physical assessments, which could then be used to design a training program based on individual strengths and weaknesses, and to determine which of these variables best identified elite performance in a group of under-19 [U19] national level handball players. Players of the U19 National Handball team (n=16) performed a set of tests to determine: 10 m (ST10) and 20 m (ST20) sprint time, ball release velocity (BRv), countermovement jump (CMJ) height and squat jump (SJ) height. All players also performed an incremental-load bench press test to determine the 1 repetition maximum (1RMest), the load corresponding to maximum mean power (LoadMP), the mean propulsive phase power at LoadMP (PMPPMP) and the peak power at LoadMP (PPEAKMP). Cluster analyses of the test results generated four groupings of players. The variables best able to discriminate physical performance were BRv, ST20, 1RMest, PPEAKMP and PMPPMP. These variables could help coaches identify talent or monitor the physical performance of athletes in their team. Each cluster of players has a particular weakness related to physical performance and therefore, the cluster results can be applied to a specific training programmed based on individual needs. PMID:28149376

A new physical performance classification system for elite handball players: cluster analysis

Directory of Open Access Journals (Sweden)

Bautista Iker J.

2016-06-01

Full Text Available The aim of the present study was to identify different cluster groups of handball players according to their physical performance level assessed in a series of physical assessments, which could then be used to design a training program based on individual strengths and weaknesses, and to determine which of these variables best identified elite performance in a group of under-19 [U19] national level handball players. Players of the U19 National Handball team (n=16 performed a set of tests to determine: 10 m (ST10 and 20 m (ST20 sprint time, ball release velocity (BRv, countermovement jump (CMJ height and squat jump (SJ height. All players also performed an incremental-load bench press test to determine the 1 repetition maximum (1RMest, the load corresponding to maximum mean power (LoadMP, the mean propulsive phase power at LoadMP (PMPPMP and the peak power at LoadMP (PPEAKMP. Cluster analyses of the test results generated four groupings of players. The variables best able to discriminate physical performance were BRv, ST20, 1RMest, PPEAKMP and PMPPMP. These variables could help coaches identify talent or monitor the physical performance of athletes in their team. Each cluster of players has a particular weakness related to physical performance and therefore, the cluster results can be applied to a specific training programmed based on individual needs.

Veto players

NARCIS (Netherlands)

Warntjen, Andreas; Dowding, Keith

2010-01-01

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

Caffeine Improves Basketball Performance in Experienced Basketball Players

Directory of Open Access Journals (Sweden)

Carlos Puente

2017-09-01

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.

Cortical thickness and subcortical brain volumes in professional rugby league players

Directory of Open Access Journals (Sweden)

Magdalena Wojtowicz

Full Text Available Purpose: The purpose of this study was to examine cortical thickness and subcortical volumes in professional rugby players with an extensive history of concussions compared to control subjects. Method: Participants included 24 active and former professional rugby league players [Age M(SD = 33.3(6.3; Range = 21–44] with an extensive history of concussion and 18 age- and education-matched controls with no history of neurotrauma or participation in contact sports. Participants underwent T1-weighted imaging and completed a neuropsychological battery, including two tests of memory. Whole brain cortical thickness analysis and structural volume analysis was performed using FreeSurfer version 6.0. Results: Professional rugby league players reported greater alcohol consumption (p < .001 and had significantly worse delayed recall of a visually complex design (p = .04. They did not differ from controls on other clinical outcome measures. There were no differences in cortical thickness between the groups. Professional players had smaller whole brain (p = .003, bilateral hippocampi (ps = .03, and left amygdala volumes (p = .01 compared to healthy controls. Within the players group, there were significant associations between greater alcohol use and smaller bilateral hippocampi and left amygdala volumes. There were no associations between structural volumes and history of concussions or memory performance. Conclusions: The literature examining cortical thickness in athletes with a history of multiple concussions is mixed. We did not observe differences in cortical thickness in professional rugby league players compared to controls. However, smaller subcortical volumes were found in players that were, in part, associated with greater alcohol consumption. Keywords: Volumetric MRI, Cortical thickness, Concussion, Brain morphometry, Athletes, Rugby

ANALYSIS AND COMPARISON OF ADOLESCENT ATHLETES' MOTIVATION: BASKETBALL PLAYERS VS. FOOTBALL PLAYERS

Directory of Open Access Journals (Sweden)

Bartolom\\u00E9 J. Almagro

2009-01-01

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.

Short-term Outcomes following Concussion in the NFL: An 11-year Retrospective Study of Player Release Rate and Financial Loss

Science.gov (United States)

Ramkumar, Prem; Navarro, Sergio Michael

2017-01-01

Objectives: The primary goal of this study was to assess the short-term outcomes among National Football League (NFL) players following concussion in terms of: (1) DNP protocol activation, (2) release rate at one and three years, and (3) mean salary reduction. A secondary goal of the study was to stratify the post-concussive release rate by franchise and player position. Methods: NFL player transaction records and publicly available weekly injury reports from August 2005 to January 2016 for NFL players were analyzed. All players immediately sustaining recorded concussions were evaluated for a change to inactive or do-not-play (DNP) status. The one-year and three-year release rate following concussion was defined as any player transitioning to inactivation, retirement, free agency, or any failure to return for a successive season on the same team’s active roster after one or three years from the initial concussion. Student’s t-test was used to compare release rates between non-concussed and concussed players at one and three years. Mean salary reduction per year following concussion was calculated using publicly available player contracts. Additionally, franchise-level and position-based analyses of the release rate were performed. Results: Of the total 5,451 NFL players retrospectively analyzed over the 11-year period, 373 sustained publicly reported concussions resulting in DNP protocol activation. The release rate of the post-concussive versus non-concussive player was 26% vs. 20% at 1 year (pfranchise to release an athlete following concussion within one and three years. Table 1 reports a position-based analysis in terms of concussion rate, mean salary reduction, and NFL career longevity. Conclusion: Our retrospective study demonstrates that NFL concussions resulting in DNP protocol activation leads to a statistically greater release rate among concussed NFL players than non-concussed players. Released players suffered reduction in year-over-year accumulated

Perceptual training in soccer: An imagery intervention study with elite players

NARCIS (Netherlands)

Jordet, G.

The purpose of this study was to determine whether an ecological imagery intervention program would affect perception (i.e., exploratory activity and prospective control of future actions) in three elite soccer players. The imagery was adjusted to the unique action opportunities typically

Menstrual cycle disorders in female volleyball players.

Science.gov (United States)

Wodarska, M; Witkoś, J; Drosdzol-Cop, A; Dąbrowska, J; Dąbrowska-Galas, M; Hartman, M; Plinta, R; Skrzypulec-Plinta, V

2013-07-01

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.

Cognitive Functions in Elite and Sub-Elite Youth Soccer Players Aged 13 to 17 Years.

Science.gov (United States)

Huijgen, Barbara C H; Leemhuis, Sander; Kok, Niels M; Verburgh, Lot; Oosterlaan, Jaap; Elferink-Gemser, Marije T; Visscher, Chris

2015-01-01

Soccer players are required to anticipate and react continuously in a changing, relatively unpredictable situation in the field. Cognitive functions might be important to be successful in soccer. The current study investigated the relationship between cognitive functions and performance level in elite and sub-elite youth soccer players aged 13-17 years. A total of 47 elite youth soccer players (mean age 15.5 years, SD = 0.9) and 41 sub-elite youth soccer players (mean age 15.2 years, SD = 1.2) performed tasks for "higher-level" cognitive functions measuring working memory (i.e., Visual Memory Span), inhibitory control (i.e., Stop-Signal Task), cognitive flexibility (i.e., Trail Making Test), and metacognition (i.e., Delis-Kaplan Executive Function System Design Fluency Test). "Lower-level" cognitive processes, i.e., reaction time and visuo-perceptual abilities, were also measured with the previous tasks. ANOVA's showed that elite players outscored sub-elite players at the "higher-level" cognitive tasks only, especially on metacognition (p soccer players on inhibitory control (p = .001), and cognitive flexibility (p = .042), but not on metacognition (p = .27). No differences were found concerning working memory nor the "lower-level" cognitive processes (p > .05). In conclusion, elite youth soccer players have better inhibitory control, cognitive flexibility, and especially metacognition than their sub-elite counterparts. However, when training hours are taken into account, differences between elite and sub-elite youth soccer players remain apparent on inhibitory control and cognitive flexibility in contrast to metacognition. This highlights the need for longitudinal studies to further investigate the importance of "higher-level" cognitive functions for talent identification, talent development and performance in soccer.

Role-player expectations regarding the education of nursing research

Directory of Open Access Journals (Sweden)

SCD Zeelie

2003-09-01

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.

Vitamin D profile in National Football League players.

Science.gov (United States)

Maroon, Joseph C; Mathyssek, Christina M; Bost, Jeffrey W; Amos, Austin; Winkelman, Robert; Yates, Anthony P; Duca, Mark A; Norwig, John A

2015-05-01

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

[Dietary behaviours of volleyball and basketball players].

Science.gov (United States)

Szczepańska, Elzbieta; Spałkowska, Agnieszka

2012-01-01

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

A study of static, kinetic, and dynamic visual acuity in 102 Japanese professional baseball players

Directory of Open Access Journals (Sweden)

Hoshina K

2013-03-01

Full Text Available Kohji Hoshina,1 Yuichi Tagami,2 Osamu Mimura,3 Hiroshi Edagawa,4 Masao Matsubara,5 Teiichi Nakayama6 1Hoshina Eye Clinic, Nishinomiya, Japan; 2Department of Ophthalmology, Kobe Century Memorial Hospital, Kobe, Japan; 3Department of Ophthalmology, Hyogo College of Medicine, Nishinomiya, Japan; 4Edagawa Eye Clinic, Tokyo, Japan; 5Department of Ophthalmology, Tokyo Women's Medical University Medical Center East, Tokyo, Japan; 6Ritsumeikan University, Kyoto, Japan Background: It seemed that visual functions might have some effects on the performance of baseball players. We measured static, kinetic, and dynamic visual acuity (SVA, KVA, and DVA, respectively of Japanese professional baseball players to ascertain whether there would be any difference in SVA, KVA, and DVA among player groups stratified according to their performance level. Methods: The subjects were 102 male professional baseball players with a mean age of 26 years who were members of a Japanese professional baseball club from 2000 to 2009. They were stratified into three groups according to their performance level: A (players who were on the roster of the top-level team all the time throughout the study period, B (players who were on the roster of the top-level team sometimes but not all the time, and C (players who were never on the roster of the top-level team. They were interviewed for the use of corrective visual aids, and examined for SVA, KVA, and DVA. The measurements of these parameters were compared among groups A, B, and C. We also investigated and analyzed the association of KVA or DVA with player position (pitchers or fielders and with hand dominance for batting. KVA was compared between the pitchers and the fielders because they each require different playing skills. DVA was compared between the right-handed and the left-handed batters. Results: There was no statistically significant difference among groups A, B, and C. There was a statistically significant difference in

High School Rugby Players' Perception of Coaching Effectiveness

Science.gov (United States)

Broodryk, Retief; van den Berg, Pieter Hendrick

2011-01-01

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…

Reimagining Game Design: Exploring the Design of Constructible Authentic Representations for Science Reasoning

Science.gov (United States)

Holbert, Nathan Ryan

Video games have recently become a popular space for educational design due to their interactive and engaging nature and the ubiquity of the gaming experience among youth. Though many researchers argue video games can provide opportunities for learning, educational game design has focused on the classroom rather than the informal settings where games are typically played. Educational games have been moderately successful at achieving learning gains on standardized items, but have failed to show improvements on related but distal problems. In this dissertation I develop and assess a new design principle, called constructible authentic representations for creating informal gaming experiences that players will actively draw on when reasoning in formal and real world contexts. These games provide players with opportunities to engage in meaningful construction with components that integrate relevant concepts to create in-game representations that visually and epistemologically align with related tools and representations utilized in the target domain. In the first phase of the dissertation, I observed children playing popular video games to better understand what in-game representations children attend to and how interactions with these representations contribute to intuitive ideas of encountered STEM content. Results from this study fed into the iterative design of two prototype video games, FormulaT Racing and Particles!, intending to give players useful knowledge resources for reasoning about kinematics and the particulate nature of matter respectively. Designed games encourage players to utilize and refine intuitive ideas about target content through the construction of domain relevant representations. To assess the effectiveness of these designs I conducted two studies of children ages 7-14 playing prototype games in informal settings. An analysis of pre- and post-game clinical interviews, domain specific tasks, and video and logging data of gameplay suggests

Somatosensory Nerve Function, Measured by Vibration Thresholds in Asymptomatic Tennis Players: A Pilot Study

Directory of Open Access Journals (Sweden)

Sarah Harrisson

2015-06-01

Full Text Available Tennis players are vulnerable to injury in their upper limbs due to the repetitive exposure to racket vibrations and torsional forces during play, leading to musculoskeletal adaptations in the dominant arm including some evidence of changes in nerve function (Colak et al., 2004. Vibration is a sensitive technique for diagnosing mild pathology in clinically asymptomatic participant groups. It has been used in participants with various musculoskeletal disorders (Laursen et al., 2006 (Tucker et al., 2007 showing widespread and bilateral increases in vibration threshold. Tests of somatosensory function by vibration will be abnormal prior to changes in nerve conduction velocity. Thus vibration testing in a sub-clinical group of participants may a more sensitive measure of nerve function compared to nerve conduction by electrodiagnostic testing. The aim of this pilot study was to conduct an exploratory investigation to establish whether tennis players have a reduction in their somatosensory nerve function compared to non- tennis playing controls. It also set out to compare the somatosensory nerve function of the dominant compared to the non-dominant upper limb in tennis players. Healthy tennis players (males, n = 8, females, n = 2, mean age 22 years and control non- tennis playing volunteers (males, n = 6, females, n = 4, mean age 22 years were recruited on an opportunistic basis from a tennis centre in London UK. Participants were excluded if they had any history of neurological impairment, serious injury or fracture or any arthritic condition affecting the upper limbs, cervical or thoracic spine. Control participants were excluded if it was deemed that they played a sport where there was exposure to repetitive use of the upper body. Ethical approval was obtained from the University College London Ethics Committee and all participants gave written informed consent. A preliminary clinical examination was carried out on all participants followed by

Foot morphology of Turkish football players according to foot ...

African Journals Online (AJOL)

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 ...

Translucent Players: Explaining Cooperative Behavior in Social Dilemmas

Directory of Open Access Journals (Sweden)

Valerio Capraro

2016-06-01

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.

Study Regarding the Play of the wing player at the World Handball Championship – Serbia 2013

Directory of Open Access Journals (Sweden)

Ionică CĂRĂBAŞ

2013-12-01

Full Text Available The ascension to the top of the world hierachy in hanball implies a minutiously preparation, considering all the factors of the sporting training, of the players who compose the team. If, not long ago, a team having a 9 m line and a valuable goalkeeper could lean the victory balance in its favour, nowadays, a team can not win a high level competition without having very valuable players on the other posts too. Considering the aspects presented, the study proposes to demonstrate the importance of the players` contribution who evolve on the wing post, in the modern handball game.

Assessing Cognitive Performance in Badminton Players: A Reproducibility and Validity Study

Directory of Open Access Journals (Sweden)

van de Water Tanja

2017-01-01

Full Text Available Fast reaction and good inhibitory control are associated with elite sports performance. To evaluate the reproducibility and validity of a newly developed Badminton Reaction Inhibition Test (BRIT, fifteen elite (25 ± 4 years and nine non-elite (24 ± 4 years Dutch male badminton players participated in the study. The BRIT measured four components: domain-general reaction time, badminton-specific reaction time, domain-general inhibitory control and badminton-specific inhibitory control. Five participants were retested within three weeks on the badminton-specific components. Reproducibility was acceptable for badminton-specific reaction time (ICC = 0.626, CV = 6% and for badminton-specific inhibitory control (ICC = 0.317, CV = 13%. Good construct validity was shown for badminton-specific reaction time discriminating between elite and non-elite players (F = 6.650, p 0.05. Concurrent validity for domain-general reaction time was good, as it was associated with a national ranking for elite (p = 0.70, p 0.05. In conclusion, reproducibility and validity of inhibitory control assessment was not confirmed, however, the BRIT appears a reproducible and valid measure of reaction time in badminton players. Reaction time measured with the BRIT may provide input for training programs aiming to improve badminton players’ performance.

Auditory memory function in expert chess players.

Science.gov (United States)

Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

2015-01-01

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.

Low range of ankle dorsiflexion predisposes for patellar tendinopathy in junior elite basketball players: a 1-year prospective study.

Science.gov (United States)

Backman, Ludvig J; Danielson, Patrik

2011-12-01

Patellar tendinopathy (PT) is one of the most common reasons for sport-induced pain of the knee. Low ankle dorsiflexion range might predispose for PT because of load-bearing compensation in the patellar tendon. The purpose of this 1-year prospective study was to analyze if a low ankle dorsiflexion range increases the risk of developing PT for basketball players. Cohort study (prognosis); Level of evidence, 2. Ninety junior elite basketball players were examined for different characteristics and potential risk factors for PT, including ankle dorsiflexion range in the dominant and nondominant leg. Data were collected over a 1-year period and follow-up, including reexamination, was made at the end of the year. Seventy-five players met the inclusion criteria. At the follow-up, 12 players (16.0%) had developed unilateral PT. These players were found to have had a significantly lower mean ankle dorsiflexion range at baseline than the healthy players, with a mean difference of -4.7° (P = .038) for the dominant limb and -5.1° (P = .024) for the nondominant limb. Complementary statistical analysis showed that players with dorsiflexion range less than 36.5° had a risk of 18.5% to 29.4% of developing PT within a year, as compared with 1.8% to 2.1% for players with dorsiflexion range greater than 36.5°. Limbs with a history of 2 or more ankle sprains had a slightly less mean ankle dorsiflexion range compared to those with 0 or 1 sprain (mean difference, -1.5° to -2.5°), although this was only statistically significant for nondominant legs. This study clearly shows that low ankle dorsiflexion range is a risk factor for developing PT in basketball players. In the studied material, an ankle dorsiflexion range of 36.5° was found to be the most appropriate cutoff point for prognostic screening. This might be useful information in identifying at-risk individuals in basketball teams and enabling preventive actions. A history of ankle sprains might contribute to reduced ankle

Return to rugby after brain concussion: a prospective study in 35 high level rugby players.

Science.gov (United States)

Chermann, Jean Francois; Klouche, Shahnaz; Savigny, Alexis; Lefevre, Nicolas; Herman, Serge; Bohu, Yoann

2014-12-01

Although guidelines based on expert opinions have been developed for the immediate management and return to play of athletes after a concussion, data are lacking on this issue. Evaluate a standardized management of brain concussion among rugby players to prevent the recurrence. A prospective study was performed from September 2009 to June 2012. All rugby players who had a concussion when playing rugby were included. Patients were managed by a specialized hospital team with a specific protocol developed in collaboration with the medical staff of the rugby clubs included in the study. The series included 35 rugby players, with 23 professionals and 12 high-level players, 30 men and 5 women, mean age 23.1 ± 5.5 years old. The median number of previous concussions was 2 (0-30) episodes. According to the Cantu concussion severity classification, 3 athletes were grade 1, 12 were grade 2 and 20 were grade 3. None of the injured athletes was lost to follow-up. The primary endpoint was the occurrence of a new concussion within 3 months after the first in patients who returned to rugby. Thirty-three patients returned to rugby after a mean 22.1 ± 10 days. The recurrence rate within 3 months was 2/33 (6.1%). The median delay before returning to rugby was 21 (7-45) days. Factors associated with a delayed return to play were young age, initial loss of consciousness, severity Cantu grade 3 and post-concussive syndrome of more than 5 days. Analysis of two failures showed that the initial injury was grade 3 and that both were professional athletes and had a history of concussion. This prospective study validated the study protocol for the management of concussion in rugby players.

Physical parameters and performance values in starters and non-starters volleyball players: A brief research note

Directory of Open Access Journals (Sweden)

M.C. Marques

2009-09-01

Full Text Available The aim of this paper was to investigate the anthropometric and strength characteristics of elite male volleyball athletes and determines if differences exist in these characteristics between starters (S and non-starters players (NS. A group of 22 professional male team volleyball players participated in the study and the players were categorized as S (n= 13 and NS (n= 9. Anthropometric characteristics, countermovement jump, overhead medicine ball throwing and maximal dynamic strength were evaluated in all the subjects. Significant diferences in age, hight and weight were noticed between S and NS. There were no significant differences between the two groups in strength and power values, except for squat performance, where S were significant strong than NS. These findings provide normative data for elite male volleyball players competing in specific playing status. From a practical perspective, sport scientists and conditioning professionals should take specicif lower body strength characteristics of volleyball players into account when designing individualized training stauts specific training programmes.

Physical parameters and performance values in starters and non-starters volleyball players: A brief research note

Directory of Open Access Journals (Sweden)

M.C. Marques

2009-01-01

Full Text Available The aim of this paper was to investigate the anthropometric and strength characteristics of elite male volleyball athletes and determines if differences exist in these characteristics between starters (S and non-starters players (NS. A group of 22 professional male team volleyball players participated in the study and the players were categorized as S (n= 13 and NS (n= 9. Anthropometric characteristics, countermovement jump, overhead medicine ball throwing and maximal dynamic strength were evaluated in all the subjects. Significant diferences in age, hight and weight were noticed between S and NS. There were no significant differences between the two groups in strength and power values, except for squat performance, where S were significant strong than NS. These findings provide normative data for elite male volleyball players competing in specific playing status. From a practical perspective, sport scientists and conditioning professionals should take specicif lower body strength characteristics of volleyball players into account when designing individualized training stauts specific training programmes.

Performance enhancement effects of Fédération Internationale de Football Association's "The 11+" injury prevention training program in youth futsal players

DEFF Research Database (Denmark)

Reis, Ivan; Rebelo, António; Krustrup, Peter

2013-01-01

OBJECTIVE:: To evaluate if Fédération Internationale de Football Association's "The 11+" injury prevention program improves physical fitness and technical performance in youth futsal players. DESIGN:: Randomized cohort study. SETTING:: Futsal club. PARTICIPANTS:: Thirty-six futsal players (17.3 ± 0...

Effect of caffeine on maximal oxygen uptake in wheelchair rugby players: A randomized, placebo-controlled, double-blind study

Directory of Open Access Journals (Sweden)

Iva Klimešová

2017-03-01

Full Text Available Background: The positive effects of caffeine supplementation on strength-power and endurance performance in healthy athletes have been demonstrated in many studies. A possible mechanism for its ergogenic effect relates to its influence on the central nervous system. Post-traumatic complications in cervical spinal cord injury affect almost all body systems including the nervous system. For this reason, we expect that caffeine will have a different effect of performance in the group of athletes with spinal cord injuries. Objective: To examine the effects of caffeine supplementation on maximal aerobic power in elite wheelchair rugby players. Methods: Seven elite male wheelchair rugby players with complete cervical-level SCI (C4-Th1 were recruited (mean age: 28 ± 5.42 years; mean body mass index: 26 ± 2.84 kg/m2. The effect of caffeine was assessed by an incremental arm ergometer test until volitional exhaustion. The maximal oxygen uptake (VO2max/kg, maximum power (W max/kg, peak heart rate (HR peak, and intensity of perceived exertion (RPE were measured. Participants performed the test twice with a two-week washout period. One hour before each exercise test subjects ingested a capsule of placebo or caffeine (3 mg per kg of body weight. The tests were applied in a double-blind, randomized, repeated-measures, and cross-over design. Wheelchair rugby players were chosen because of the expected high homogeneity of participants - in terms of the type and degree of disability, gender, and age of the players. Results: The monitored parameters were not significantly influenced by caffeine intervention as compared to placebo: VO2max/kg (p = .40, W max/kg (p = .34, HR peak (p = .50 and RPE (p = .50. Conclusions: The current findings suggest that a caffeine dose of 3 mg/kg body mass does not improve oxygen uptake and maximal power in elite wheelchair rugby players.

Secure Multi-Player Protocols

DEFF Research Database (Denmark)

Fehr, Serge

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...

Soccer player recognition by pixel classification in a hybrid color space

Science.gov (United States)

Vandenbroucke, Nicolas; Macaire, Ludovic; Postaire, Jack-Gerard

1997-08-01

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

Relative Age Effect in Swedish Male and Female Tennis Players Born in 1998–2001

Directory of Open Access Journals (Sweden)

Göran Gerdin

2018-04-01

Full Text Available The relative age effect (RAE has been extensively debated and researched in both popular media and academic discourse. This study examined RAE in Swedish tennis players born in 1998–2001. The study was conducted in 2015–2016 and includes all ranked Swedish tennis players (n = 1835 registered in the Swedish Tennis Association database from the year 2014. The results show that when the birth dates of the corresponding Swedish population and all the ranked players are compared, they show a moderate RAE; however, the higher up they are in the ranking system, the greater the RAE becomes. Top 10 players display an average of 64.1% being born in the first half of the year. Some gender differences were also found, with a greater proportion of both higher and lower ranked females being born in the first half of the year. In our discussion of the findings we raise several issues that need to be addressed to provide more equal opportunities for all junior players regardless of birth date. Resolving ongoing problems associated with RAE in competitive sports such as tennis is important both in term of prolonged participation in the sport and increased performance. Suggestions made in this article include recognising RAE when designing the format of competitions/tournaments, not using official rankings until the juniors get older, addressing RAE in a “gender sensitive” way, and conducting further in-depth studies in which RAE is understood/examined as being associated with environmental factors. Although these findings show the RAE effect in Swedish tennis players, thus pointing at the need for further consideration in terms of ranking and selection procedures to ensure equal opportunities for player development, the study also concludes by reasserting an emphasis on a holistic approach to player development in which coaches focus on the developmentally appropriate needs and potential of each individual player regardless of their biological age.

Using Interpretative Phenomenological Analysis in a Mixed Methods Research Design to Explore Music in the Lives of Mature Age Amateur Keyboard Players

Science.gov (United States)

Taylor, Angela

2015-01-01

This article discusses the use of interpretative phenomenological analysis (IPA) in a mixed methods research design with reference to five recent publications about music in the lives of mature age amateur keyboard players. It explores the links between IPA and the data-gathering methods of "Rivers of Musical Experience",…

Thermoregulation, Fluid Balance, and Sweat Losses in American Football Players.

Science.gov (United States)

Davis, Jon K; Baker, Lindsay B; Barnes, Kelly; Ungaro, Corey; Stofan, John

2016-10-01

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

Swimming literacy field hockey woman player ground.

OpenAIRE

Baštová, Miroslava

2012-01-01

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...

Effectiveness of an injury prevention programme for adult male amateur soccer players: a cluster-randomised controlled trial

Science.gov (United States)

van Beijsterveldt, Anna M C; van de Port, Ingrid G L; Krist, Mark R; Schmikli, Sandor L; Stubbe, Janine H; Frederiks, Janet E; Backx, Frank J G

2012-01-01

Background The incidence rate of soccer injuries is among the highest in sports, particularly for adult male soccer players. Purpose To investigate the effect of the ‘The11’ injury prevention programme on injury incidence and injury severity in adult male amateur soccer players. Study design Cluster-randomised controlled trial. Methods Teams from two high-level amateur soccer competitions were randomly assigned to an intervention (n=11 teams, 223 players) or control group (n=12 teams, 233 players). The intervention group was instructed to perform The11 in each practice session during one soccer season. The11 focuses on core stability, eccentric training of thigh muscles, proprioceptive training, dynamic stabilisation and plyometrics with straight leg alignment. All participants of the control group continued their practice sessions as usual. Results In total, 427 injuries were recorded, affecting 274 of 456 players (60.1%). Compliance with the intervention programme was good (team compliance=73%, player compliance=71%). Contrary to the hypothesis, injury incidences were almost equal between the two study groups: 9.6 per 1000 sports hours (8.4–11.0) for the intervention group and 9.7 (8.5–11.1) for the control group. No significant differences were found in injury severity, but a significant difference was observed in the location of the injuries: players in the intervention group sustained significantly less knee injuries. Conclusions This study did not find significant differences in the overall injury incidence or injury severity between the intervention and control group of adult male soccer players. More research is recommended, focusing on injury aetiology and risk factors in adult male amateur soccer players. PMID:22878257

No association between static and dynamic postural control and ACL injury risk among female elite handball and football players: a prospective study of 838 players.

Science.gov (United States)

Steffen, Kathrin; Nilstad, Agnethe; Krosshaug, Tron; Pasanen, Kati; Killingmo, Aleksander; Bahr, Roald

2017-02-01

Research on balance measures as potential risk factors for ACL injury is limited. To assess whether postural control was associated with an increased risk for ACL injuries in female elite handball and football players. Premier league players were tested in the preseason and followed prospectively for ACL injury risk from 2007 through 2015. At baseline, we recorded player demographics, playing experience, ACL and ankle injury history. We measured centre of pressure velocity in single-leg stabilisation tests and reach distances in the Star Excursion Balance Test. To examine the stability of postural control measures over time, we examined their short-term and long-term reproducibility. We generated logistic regression models, 1 for each of the proposed risk factors. A total of 55 (6.6%) out of 838 players (age 21±4 years; height 170±6 cm; body mass 66±8 kg) sustained a non-contact ACL injury after baseline testing (1.8±1.8 years). When comparing normalised balance measures between injured and uninjured players in univariate analyses, none of the variables were statistically associated with ACL injury risk. Short-term and long-term reproducibility of the selected variables was poor. Players with a previous ACL injury had a 3-fold higher risk of sustaining a new ACL injury compared with previously uninjured players (OR 2.9, CI 1.4 to 5.7). None of postural control measures examined were associated with increased ACL injury risk among female elite handball and football players. Hence, as measured in the current investigation, the variables included cannot be used to predict ACL injury risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Incidence of Stingers in Young Rugby Players.

Science.gov (United States)

Kawasaki, Takayuki; Ota, Chihiro; Yoneda, Takeshi; Maki, Nobukazu; Urayama, Shingo; Nagao, Masashi; Nagayama, Masataka; Kaketa, Takefumi; Takazawa, Yuji; Kaneko, Kazuo

2015-11-01

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

Self-determined motivation in rehabilitating professional rugby union players

OpenAIRE

Carson, F.; Polman, Remco C.J.

2017-01-01

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...

The Hedonic Haptic Player

DEFF Research Database (Denmark)

Vallgårda, Anna; Boer, Laurens; Cahill, Ben

2017-01-01

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...

Does Game Playing Experience Have an Impact on the Player-PNPC Relationship?

Science.gov (United States)

Daviault, Christine

2012-01-01

There are several types of characters in video games: the main protagonist/hero, the countless non-player characters (NPCs), and persistent non-player characters (PNPCs). While there is a substantial body of research about PNPCs from a game design point of view, they have been largely ignored by the academic community from a narrative perspective.…

Risk Factors for Injuries in Professional Football Players.

Science.gov (United States)

Haxhiu, Bekim; Murtezani, Ardiana; Zahiti, Bedri; Shalaj, Ismet; Sllamniku, Sabit

2015-01-01

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.

Coping strategies of soccer players | Plaatjie | South African Journal ...

African Journals Online (AJOL)

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 ...

Half-time re-warm up increases performance capacity in male elite soccer players

DEFF Research Database (Denmark)

Edholm, P; Krustrup, Peter; Randers, Morten Bredsgaard

2015-01-01

This study investigated the acute effects of a half-time re-warm up on performance and movement patterns in soccer match play. Using a crossover design, 22 professional male players performed traditional passive rest (CON) or a low-intensity re-warm up (RW) during the half-time period of two soccer.......01). Moreover, RW had more possession of the ball in the beginning of the second half. In conclusion, traditional passive half-time rest leads to impaired sprint and jump performance during the initial phase of the second half in professional soccer players whereas a re-warm up effectively attenuates...

Bone Mineral Density of Adolescent Female Tennis Players and Nontennis Players

Directory of Open Access Journals (Sweden)

Kevser Ermin

2012-01-01

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.

Sensory organisation and reactive balance control of amateur rugby players: A cross-sectional study.

Science.gov (United States)

Chow, Gary C C; Chung, Joanne W Y; Ma, Ada W W; Macfarlane, Duncan J; Fong, Shirley S M

2017-05-01

This study compared the sensory organisation and reactive balance control of amateur rugby players and a control group. Forty-one amateur rugby players (22 males: 19 females; mean height ± SD = 168.8 ± 8.8 cm; mean weight ± SD = 63.9 ± 12.5 kg) and 31 control participants (22 males: 9 females; mean height ± SD = 171.5 ± 10.3 cm; mean weight ± SD = 63.8 ± 10.3 kg) completed the study. Their sensory organisation and standing balance performance were evaluated using a sensory organisation test (SOT), and their reactive balance performance was quantified using a motor control test (MCT). The SOT equilibrium scores (ES) and sensory ratios and the MCT motor response latencies were the major outcome measures. The results revealed that compared to the controls, amateur rugby players had lower SOT ESs under different sensory environments (P rugby group (P = .005, [Formula: see text] = 0.107 and 0.108, respectively). No significant difference was found in the somatosensory ratio (P = .853, [Formula: see text] rugby players demonstrated inferior standing balance performance compared to their non-trained counterparts. They relied less heavily on vestibular and visual inputs to maintain standing balance under different sensory environments. In addition, they reacted more slowly to postural disturbance, reflecting their suboptimal reactive balance ability in standing.

The Psychological Study of Video Game Players: Methodological Challenges and Practical Advice

Science.gov (United States)

King, Daniel; Delfabbro, Paul; Griffiths, Mark

2009-01-01

Video game playing has received increased academic interest over the last few decades, particularly with regard to the psychological understanding of addiction. Based on the many studies carried out by the authors, this paper summarises some of the methodological challenges which may arise when studying video game players, including obstacles…

Dominant-limb range-of-motion and humeral-retrotorsion adaptation in collegiate baseball and softball position players.

Science.gov (United States)

Hibberd, Elizabeth E; Oyama, Sakiko; Tatman, Justin; Myers, Joseph B

2014-01-01

Biomechanically, the motions used by baseball and softball pitchers differ greatly; however, the throwing motions of position players in both sports are strikingly similar. Although the adaptations to the dominant limb from overhead throwing have been well documented in baseball athletes, these adaptations have not been clearly identified in softball players. This information is important in order to develop and implement injury-prevention programs specific to decreasing the risk of upper extremity injury in softball athletes. To compare range-of-motion and humeral-retrotorsion characteristics of collegiate baseball and softball position players and of baseball and softball players to sex-matched controls. Cross-sectional study. Research laboratories and athletic training rooms at the University of North Carolina at Chapel Hill. Fifty-three collegiate baseball players, 35 collegiate softball players, 25 male controls (nonoverhead athletes), and 19 female controls (nonoverhead athletes). Range of motion and humeral retrotorsion were measured using a digital inclinometer and diagnostic ultrasound. Glenohumeral internal-rotation deficit, external-rotation gain, total glenohumeral range of motion, and humeral retrotorsion. Baseball players had greater glenohumeral internal-rotation deficit, total-range-of-motion, and humeral-retrotorsion difference than softball players and male controls. There were no differences between glenohumeral internal-rotation deficit, total-range-of-motion, and humeral-retrotorsion difference in softball players and female controls. Few differences were evident between softball players and female control participants, although range-of-motion and humeral-retrotorsion adaptations were significantly different than baseball players. The throwing motions are similar between softball and baseball, but the athletes adapt to the demands of the sport differently; thus, stretching/strengthening programs designed for baseball may not be the most

I Fought the Law: Transgressive Play and The Implied Player

DEFF Research Database (Denmark)

Aarseth, Espen J.

2007-01-01

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...

Is the internal training load different between starters and nonstarters volleyball players submitted to the same external load training? A case study

Directory of Open Access Journals (Sweden)

Thiago Andrade Goulart Horta

2017-11-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2017v19n4p395   The same training stimulus can provide different physiological adaptations for athletes of the same team. Thus, the aim of this study was to analyze and compare the load training of starters and nonstarters players, athletes of a men’s volleyball team at different times of the season. The sample consisted of fifteen men’s volleyball superleague athletes who were divided into two groups of starters and nonstarters players. The training load of the ten weeks of the team’s preparation period for the main championship season in which no games were performed was selected for the study. The method of subjective perceived of effort (session-RPE proposed by Foster et al. (2001 was used to quantify the training load. The group of starters players had higher total weekly training load (TWTL and RPE values in the average of the ten weeks of training (p<0.05. Higher TWTL values for starters players in the preparatory and pre-competitive period compared to nonstarters players was also demonstrated (p<0.05. When different weeks were analyzed separately, weeks three and seven presented higher TWTL and RPE values for starters players compared with nonstarters players (p<0.05. The results presented in this study showed that starters players showed greater internal training load compared to nonstarters players.

Health amongst former rugby union players: A cross-sectional study of morbidity and health-related quality of life.

Science.gov (United States)

Davies, Madeleine A M; D Judge, Andrew; Delmestri, Antonella; P T Kemp, Simon; Stokes, Keith A; Arden, Nigel K; Newton, Julia L

2017-09-28

In the general population, physical activity is associated with improved health outcomes. However, long-term sports participation may be associated with adverse outcomes, particularly at the elite level. The aims of this study were to assess morbidity and health-related quality of life (HrQoL) amongst former rugby players, compared to an age-standardised general population sample. A cross-sectional study of former elite, male, rugby players (n = 259) was undertaken, and standardised morbidity ratios (SMR) calculated, assessing morbidity prevalence relative to English Longitudinal Study of Aging participants (ELSA, n = 5186). HrQoL, measured using the EQ-5D, was compared to a Health Survey for England (HSE, n = 2981) sample. In SMR analyses of participants aged 50+, diabetes was significantly lower amongst former players, (0.28, 95% CI 0.11-0.66), whereas osteoarthritis (4.00, 95% CI 3.32-4.81), joint replacement (6.02, 95% CI 4.66-7.77), osteoporosis (2.69, 95% CI 1.35-5.38), and anxiety (2.00, 95% CI 1.11-3.61) were significantly higher. More problems in HrQoL were reported amongst former players within the domains of mobility (p < 0.001), self-care (p = 0.041), usual activities (p < 0.001) and pain/discomfort (p < 0.001). Morbidity and HrQoL differ between players and the general population, with higher musculoskeletal morbidity and lower diabetes amongst former players. The magnitude of musculoskeletal morbidity may warrant proactive osteoarthritis management within this population.

Performance following a first professional concussion among National Basketball Association players.

Science.gov (United States)

Yengo-Kahn, Aaron M; Zuckerman, Scott L; Stotts, Jeff; Zalneraitis, Brian H; Gardner, Ryan M; Kerr, Zachary Y; Solomon, Gary S

2016-09-01

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.

The players in the French photovoltaic sector

International Nuclear Information System (INIS)

Houot, G.

2011-01-01

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.)

Head Impact Exposure in Junior and Adult Australian Football Players

Directory of Open Access Journals (Sweden)

Mark Hecimovich

2018-01-01

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.

Injuries in Spanish female soccer players

Directory of Open Access Journals (Sweden)

Juan Del Coso

2018-04-01

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

Case Study: Nutritional and Lifestyle Support to Reduce Infection Incidence in an International-Standard Premier League Soccer Player.

Science.gov (United States)

Ranchordas, Mayur K; Bannock, Laurent; Robinson, Scott L

2016-04-01

Professional soccer players are exposed to large amounts of physiological and psychological stress, which can increase infection risk and threaten availability for training and competition. Accordingly, it is important for practitioners to implement strategies that support player well-being and prevent illness. This case study demonstrates how a scientifically supported and practically applicable nutrition and lifestyle strategy can reduce infection incidence in an illness-prone professional soccer player. In the 3 months before the intervention, the player had 3 upper-respiratory tract infections (URTIs) and subsequently missed 3 competitive matches and 2 weeks' training. He routinely commenced morning training sessions in the fasted state and was estimated to be in a large daily energy deficit. Throughout the 12-week intervention, the amount, composition, and timing of energy intake was altered, quercetin and vitamin D were supplemented, and the player was provided with a daily sleep and hygiene protocol. There was a positive increase in serum vitamin D 25(OH) concentration from baseline to Week 12 (53 n·mol-1 to 120 n·mol-1) and salivary immunoglobulin-A (98 mg·dl-1 to 135 mg·dl-1), as well as a decline in the number of URTI symptoms (1.8 ± 2.0 vs. 0.25 ± 0.5 for Weeks 0-4 and Weeks 8-12, respectively). More important, he maintained availability for all training and matches over the 12-week period. We offer this case study as a real-world applied example for other players and practitioners seeking to deploy nutrition and lifestyle strategies to reduce risk of illness and maximize player availability.

Exploring Stereotypical Perceptions of Female Players in Digital Gaming Contexts.

Science.gov (United States)

Kaye, Linda K; Gresty, Claire E; Stubbs-Ennis, Natasha

2017-12-01

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.

Physical and physiological attributes of female volleyball players--a review.

Science.gov (United States)

Lidor, Ronnie; Ziv, Gal

2010-07-01

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.

A Profile of Fitness Parameters and Performance of Volleyball Players

Directory of Open Access Journals (Sweden)

Govind B. Taware

2013-07-01

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.

Exploring Online Game Players' Flow Experiences and Positive Affect

Science.gov (United States)

Chiang, Yu-Tzu; Lin, Sunny S. J.; Cheng, Chao-Yang; Liu, Eric Zhi-Feng

2011-01-01

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,…

Is There Any Association Between Foot Posture and Lower Limb-Related Injuries in Professional Male Basketball Players? A Cross-Sectional Study.

Science.gov (United States)

Lopezosa-Reca, Eva; Gijon-Nogueron, Gabriel; Morales-Asencio, Jose Miguel; Cervera-Marin, Jose Antonio; Luque-Suarez, Alejandro

2017-12-19

Several studies have shown that foot posture is related to the incidence of ankle sprains in athletes and in nonathletic populations, but this association has not previously been considered in basketball players. This study investigates the relationship between foot posture and lower limb injuries in elite basketball players. Two hundred twenty participants were recruited as a convenience sample. The players had a mean age of 22.51 ± 3.88 years and a body mass index of 23.98 ± 1.80. The players' medical records were accessed from the preceding 10 years, and injuries were recorded according to their location (knee, foot, and/or ankle). In addition, the Foot Posture Index (FPI) was scored for each player, and their playing positions were noted. An average FPI score of 2.66 was obtained across all players, with guards presenting a significantly lower average FPI of -0.48 (P patellar tendinopathy (n = 126). Patellar tendinopathy was more common in supinated feet (30.08%) compared with 20.7% and 19.8% in pronated and neutral feet, respectively. The most common lower limb injuries observed in basketball players were lateral ankle sprain and patellar tendinopathy. Patellar tendinopathy was more commonly associated with the supinated feet. Guard players tended to have a more supinated foot, whereas centers presented a more pronated foot.

Experiences of time loss among videogame players: an empirical study.

Science.gov (United States)

Wood, Richard T A; Griffiths, Mark D; Parke, Adrian

2007-02-01

Playing videogames is now a major leisure pursuit, yet research in the area is comparatively sparse. Previous correlational evidence suggests that subjective time loss occurs during playing videogames. This study examined experiences of time loss among a relatively large group of gamers (n = 280). Quantitative and qualitative data were collected through an online survey. Results showed that time loss occurred irrespective of gender, age, or frequency of play, but was associated with particular structural characteristics of games such as their complexity, the presence of multi-levels, missions and/or high scores, multiplayer interactions, and plot. Results also demonstrated that time loss could have both positive and negative outcomes for players. Positive aspects of time loss included helping players to relax and temporarily escape from reality. Negative aspects included the sacrificing of other things in their lives, guilty feelings about wasted time, and social conflict. It is concluded that for many gamers, losing track of time is a positive experience and is one of the main reasons for playing videogames.

The effects of resistance training on explosive strength indicators in adolescent basketball players.

Science.gov (United States)

Santos, Eduardo J A M; Janeira, Manuel A A S

2012-10-01

The purpose of this study was to assess the effects of a lower- and upper-body 10-week in-season resistance training program on explosive strength development in young basketball players. Twenty-five adolescent male athletes, aged 14-15 years old, were randomly assigned to an experimental group (EG; n = 15) and a control group (CG; n = 10). The subjects were assessed at baseline and after training for squat jump (SJ), countermovement jump (CMJ), Abalakov test, drop jump, and seated medicine ball throw (MBT). The EG showed significant increases (p training program with moderate volume and intensity loads increased vertical jump and MBT performance in adolescent male basketball players. Coaches should know that such a short resistance training program specifically designed for young basketball players induce increased explosivity levels, which are essential to a better basketball performance, with no extra overload on adolescents' skeletal muscle development.

Sports hernia in National Hockey League players: does surgery affect performance?

Science.gov (United States)

Jakoi, Andre; O'Neill, Craig; Damsgaard, Christopher; Fehring, Keith; Tom, James

2013-01-01

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

Talent identification and early development of elite water-polo players: a 2-year follow-up study.

Science.gov (United States)

Falk, Bareket; Lidor, Ronnie; Lander, Yael; Lang, Benny

2004-04-01

The processes of talent detection and early development are critical in any sport programme. However, not much is known about the appropriate strategies to be implemented during these processes, and little scientific inquiry has been conducted in this area. The aim of this study was to identify variables of swimming, ball handling and physical ability, as well as game intelligence, which could assist in the selection process of young water-polo players. Twenty-four players aged 14-15 years underwent a battery of tests three times during a 2-year period, before selection to the junior national team. The tests included: freestyle swim for 50, 100, 200 and 400 m, 100-m breast-stroke, 100-m 'butterfly' (with breast-stroke leg motion), 50-m dribbling, throwing at the goal, throw for distance in the water, vertical 'jump' from the water, and evaluation of game intelligence by two coaches. A comparison of those players eventually selected to the team and those not selected demonstrated that, 2 years before selection, selected players were already superior on most of the swim tasks (with the exception of breast-stroke and 50-m freestyle), as well as dribbling and game intelligence. This superiority was maintained throughout the 2 years. Two-way tabulation revealed that, based on baseline scores, the prediction for 67% of the players was in agreement with the final selection to the junior national team. We recommend that fewer swim events be used in the process of selecting young water-polo players, and that greater emphasis should be placed on evaluation of game intelligence.

Caffeine-containing energy drink improves physical performance in female soccer players.

Science.gov (United States)

Lara, Beatriz; Gonzalez-Millán, Cristina; Salinero, Juan Jose; Abian-Vicen, Javier; Areces, Francisco; Barbero-Alvarez, Jose Carlos; Muñoz, Víctor; Portillo, Luis Javier; Gonzalez-Rave, Jose Maria; Del Coso, Juan

2014-05-01

There is little information about the effects of caffeine intake on female team-sport performance. The aim of this study was to investigate the effectiveness of a caffeine-containing energy drink to improve physical performance in female soccer players during a simulated game. A double-blind, placebo controlled and randomized experimental design was used in this investigation. In two different sessions, 18 women soccer players ingested 3 mg of caffeine/kg in the form of an energy drink or an identical drink with no caffeine content (placebo). After 60 min, they performed a countermovement jump (CMJ) and a 7 × 30 m sprint test followed by a simulated soccer match (2 × 40 min). Individual running distance and speed were measured using GPS devices. In comparison to the placebo drink, the ingestion of the caffeinated energy drink increased the CMJ height (26.6 ± 4.0 vs 27.4 ± 3.8 cm; P 18 km/h (161 ± 99 vs 216 ± 103 m; P caffeine/kg might be an effective ergogenic aid to improve physical performance in female soccer players.

Voluntary limit setting and player choice in most intense online gamblers: an empirical study of gambling behaviour.

Science.gov (United States)

Auer, Michael; Griffiths, Mark D

2013-12-01

Social responsibility in gambling has become a major issue for the gaming industry. The possibility for online gamblers to set voluntary time and money limits are a social responsibility practice that is now widespread among online gaming operators. The main issue concerns whether the voluntary setting of such limits has any positive impact on subsequent gambling behaviour and whether such measures are of help to problem gamblers. In this paper, this issue is examined through data collected from a representative random sample of 100,000 players who gambled on the win2day gambling website. When opening an account at the win2day site, there is a mandatory requirement for all players to set time and cash-in limits (that cannot exceed 800 per week). During a 3-month period, all voluntary time and/or money limit setting behaviour by a subsample of online gamblers (n = 5,000) within this mandatory framework was tracked and recorded for subsequent data analysis. From the 5,000 gamblers, the 10 % most intense players (as measured by theoretical loss) were further investigated. Voluntary spending limits had the highest significant effect on subsequent monetary spending among casino and lottery gamblers. Monetary spending among poker players significantly decreased after setting a voluntary time limit. The highest significant decrease in playing duration was among poker players after setting a voluntary playing duration limit. The results of the study demonstrated that voluntary limit setting had a specific and significant effect on the studied gamblers. Therefore, voluntary limits appear to show an appropriate effect in the desired target group (i.e., the most gaming intense players).

A comparison of the musculoskeletal assessments of the shoulder girdles of professional rugby players and professional soccer players

Directory of Open Access Journals (Sweden)

Horsley Ian G

2012-09-01

Full Text Available Abstract Objective To identify posture types that exist in professional rugby players, and compare them with a population of non-overhead athletes in order to identify possible relationships towards the potential for shoulder injuries. Design Observational design Setting: Sports Medicine Clinic Participants: Convenience sample Methodology: Static assessment of posture was carried out in standing, active and passive range of glenohumeral motion, and isometric strength was carried out in accordance with previously recorded protocols. Interventions Nil Outcome Measures: Observational classification of posture, active and passive range of glenohumeral joint range of motion, isometric strength of selected muscle groups, selected muscle flexibility and Hawkins and Neer impingement tests. Results There was a significant difference on range of motion between the two groups (0.025–0.000, isometric middle (0.024–0.005, and lower trapezius (0.01–0.001. Conclusion: There were significant differences between strength and flexibility of muscles around the shoulder girdle between professional rugby players and a control group of professional non-overhead athletes.

Decreased shoulder function and pain common in recreational badminton players.

Science.gov (United States)

Fahlström, M; Söderman, K

2007-06-01

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.

[Muscular trunk stability in professional and amateur volleyball players].

Science.gov (United States)

Miltner, O; Siebert, C; Tschaepe, R; Maus, U; Kieffer, O

2010-03-01

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.

ANTHROPOMETRIC CHARACTERISTICS AND FUNCTIONAL CAPACITY OF ELITE ROWERS AND HANDBALL PLAYERS.

Science.gov (United States)

Karaba Jakovljevic, Dea; Jovanovic, Gordana; Eric, Mirela; Klasnja, Aleksandar; Slavic, Danijel; Lukac, Damir

2016-09-01

Anthropometric and anaerobic profile of elite athletes are fundamental for the assessment of their respective performance. The present study was designed to evaluate the anthro- pornetric parameters, body composition and anaerobic characteristics of elite male handball players and rowers, and to compare them in relation to specific sport demands. The study group consisted of 41 elite national level athletes: 20 handball players (aged 23.7±3.72) and 21 rowers (aged 19.7±2.84). Anthropometric characteristics (body mass, body height, skinfold thickness, body circumferences), and body fat mass were evaluated, and Wingate anaerobic test for anaerobic power assessment Iwas applied. The significant differences were noted in chest-upper arm, waist and hip circumferences, and supraspinal and calf skinfolds between the two investigated groups. Rowers showed higher values of fat body mass (13.2±3.76 vs. 10.7±3.76%), but lower body mass index (22.0±1,92 vs. 25.7?2.31 kg/in12) compared to handball players. When analyzing the Wingate test parameters, significantly higher values of absolute anaerobic power (786±127 vs. 691±140 W), absolute explosive power in the handball players compared to the rowers were recorded ( 18±26.3 vs. 105±27.8 W/s), whi le rowers achieved higher relative anaerobic capacity (192±3 1.2 vs. 177±E20.8 J/ kg). Specific body composition and anthropometri- cal assessment as a part of morphological analysis should complement physiological profile of elite athletes. The analysis of the anaerobic performance shows that the handball players have greater alactic anaerobic and explosive power component, compared to the rowers in whom the anaerobic endurance and specific training have the greatest effect on the consumption of dominant metabolic substrate during the race.

Does player unavailability affect football teams' match physical outputs? A two-season study of the UEFA champions league.

Science.gov (United States)

Windt, Johann; Ekstrand, Jan; Khan, Karim M; McCall, Alan; Zumbo, Bruno D

2018-05-01

Player unavailability negatively affects team performance in elite football. However, whether player unavailability and its concomitant performance decrement is mediated by any changes in teams' match physical outputs is unknown. We examined whether the number of players injured (i.e. unavailable for match selection) was associated with any changes in teams' physical outputs. Prospective cohort study. Between-team variation was calculated by correlating average team availability with average physical outputs. Within-team variation was quantified using linear mixed modelling, using physical outputs - total distance, sprint count (efforts over 20km/h), and percent of distance covered at high speeds (>14km/h) - as outcome variables, and player unavailability as the independent variable of interest. To control for other factors that may influence match physical outputs, stage (group stage/knockout), venue (home/away), score differential, ball possession (%), team ranking (UEFA Club Coefficient), and average team age were all included as covariates. Teams' average player unavailability was positively associated with the average number of sprints they performed in matches across two seasons. Multilevel models similarly demonstrated that having 4 unavailable players was associated with 20.8 more sprints during matches in 2015/2016, and with an estimated 0.60-0.77% increase in the proportion of total distance run above 14km/h in both seasons. Player unavailability had a possibly positive and likely positive association with total match distances in the two respective seasons. Having more players injured and unavailable for match selection was associated with an increase in teams' match physical outputs. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Hip Arthroscopy in High-Level Baseball Players.

Science.gov (United States)

Byrd, J W Thomas; Jones, Kay S

2015-08-01

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.

Injury Pattern in Icelandic Elite Male Handball Players.

Science.gov (United States)

Rafnsson, Elis Thor; Valdimarsson, Örnólfur; Sveinsson, Thorarinn; Árnason, Árni

2017-10-10

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.

Comparison of Lateral Abdominal Muscle Thickness and Cross Sectional Area of Multifidus in Adolescent Soccer Players with and without Low Back Pain: A Case Control Study.

Science.gov (United States)

Noormohammadpour, Pardis; Hosseini Khezri, Alireza; Linek, Paweł; Mansournia, Mohammad Ali; Hassannejad, Alireza; Younesian, Ali; Farahbakhsh, Farzin; Kordi, Ramin

2016-12-01

Low back pain (LBP) is a common complaint amongst adolescent athletes. While different studies have shown association between LBP and trunk muscle thickness in the general population, few articles have studied it in adolescent athletes. The aim of this study is to compare lateral abdominal muscle thickness and function, and cross sectional area (CSA) of lumbar multifidus (LM) in adolescent soccer players with and without LBP. In total, 28 adolescent soccer players with and without LBP, from the premier league participated in this study. The thickness of external oblique, internal oblique and transversus abdominis and the CSA of the LM muscles at L4 level on both sides were measured at rest and contraction via ultrasound imaging (USI). In addition, leg length discrepancy, hamstring flexibility, active lumbar forward flexion, and isometric muscle endurance of trunk extensors were measured in both groups. (study design/setting: case control study). The mean (SD) age in LBP group and non-LBP group were 14.0 (1.1) and 14.1 (0.9) years, respectively. There was no significant difference in baseline characteristics of participants between groups. Findings showed no significant difference between LBP and non-LBP groups comparing all measured variables. The data obtained support that there is not a correlation between abdominal muscle thickness and CSA of the lumbar multifidi and LBP in adolescent soccer players. These findings suggest that other factors rather than the thickness of deep trunk muscles may play a more significant role in the etiology of LBP in adolescent soccer players.

The El Dorado of Handball? Foreign Female Players Stay, while Domestic Players Return from Abroad

Science.gov (United States)

Topič, Mojca Doupona; Šibila, Marko

2016-01-01

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

The El Dorado of Handball? Foreign Female Players Stay, while Domestic Players Return from Abroad

Directory of Open Access Journals (Sweden)

Bon Marta

2016-04-01

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.

Effect of Concussion on Performance of National Football League Players.

Science.gov (United States)

Reams, Nicole; Hayward, Rodney A; Kutcher, Jeffrey S; Burke, James F

2017-09-01

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.

The Effect of Different Warm-up Protocols on young Soccer Players' Explosive Power

Directory of Open Access Journals (Sweden)

Mohamad Ali Mohamadi

2012-12-01

Full Text Available Objective: To investigating the effect of different Warm-up Protocols on young Soccer Players' Explosive Power. Methods: Twenty male soccer players (17.4 0.685 years volunteered to participate in this study. The participants were randomly selected, and in order to remove the effects of transmission and to observe the sequence of warm-up methods, they were cross-matched randomly e.g. 20 players in four categories; that is, 5 players in each category. The participants in each category experienced the 4 warm-up ways in four consecutive so that at the end 20 players performed each method of warm-up. Warm-up methods: 1. Static warm-up; 2. Dynamic warm-up plus 2 min active rest; 3. Dynamic warm-up plus 5 min passive rest and finally Dynamic warm-up plus 15 min passive rest. Participants in each category performed different warm-up methods which had been designed based on scientific and research-based sources in 48 hours intervals After performing each warm-up method, they were given a Long Jump. Results: Based on the results of analysis of variance between the effect of different warm-up methods on Explosive Power participants, significant difference was observed (p?0/05 so that Dynamic warm-up plus 5 min passive rest was more effective in Explosive Power performance than other methods(p?0/05. Discussion: The results of this study are in line with those of Roger (2008 and Faigenbaum et al (2006 who indicated in their studies that Dynamic or mixed method of warm-up are more effective than static ones. Conclusion: Therefore, with regard to the results of the study presented here and also the nature of football enjoying explosive power than the air blows, it is recommended that these types of protocols during warm-up program be employed.   Keywords: Warm up, Explosive Power , Soccer Players', Young  

An Examination of Coach and Player Relationships According to the Adapted LMX 7 Scale: A Validity and Reliability Study

Science.gov (United States)

Caliskan, Gokhan

2015-01-01

The current study aims to test the reliability and validity of the Leader-Member Exchange (LMX 7) scale with regard to coach--player relationships in sports settings. A total of 330 professional soccer players from the Turkish Super League as well as from the First and Second Leagues participated in this study. Factor analyses were performed to…

Seasonal player wellness and its longitudinal association with internal training load: study in elite volleyball.

Science.gov (United States)

Clemente, Filipe M; Mendes, Bruno; Palao, José M; Silvério, André; Carriço, Sandro; Calvete, Francisco; Nakamura, Fábio Y

2018-04-04

Monitoring training load is critical to minimize the risk of overreaching, injury or illness. The purpose of this study was to assess the relationships and variance between perceived internal load and wellness status of elite male volleyball. Thirteen elite volleyball players were studied during a full competitive season (nine months, 237 training sessions and 37 official matches). Perceived exertion, muscle soreness, stress, fatigue and sleep quality levels were daily measured using session RPE and the Hopper Questionnaire. Moderate-to-large correlations were found between weekly training load and perceived status of muscle soreness, fatigue and stress. Stronger correlations were found between weekly training loads than daily training load. Significant greater stress levels in match days than in training were found. No correlations between load and wellness were not found in the last month when players perceived higher levels of stress due to the competition. The analysis of the weekly training load had a higher relationship with players' wellness status in pre-season and middle of the season. In the last part of the season (final matches for the title), despite of a decrease in perceived load of last month of the season, there was an increase stress and fatigue levels. These results suggest the importance of including the impact on the competition when elite athletes are monitored. The results show the monitoring tools used may help in to characterize the training process of teams and the player's acute and chronic responses.

Profiling in basketball: physical and physiological characteristics of elite players.

Science.gov (United States)

Ostojic, Sergej M; Mazic, Sanja; Dikic, Nenad

2006-11-01

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.

Operative shoulder instability injury management in Australian Football League players: A case series.

Science.gov (United States)

Bonacci, Jason; Manson, Brent; Bowe, Steven J; Gill, Stephen; Seward, Hugh; Hoy, Greg; Page, Richard

2017-11-27

The purpose of this study was to review the surgical management procedures of shoulder instability injuries in Australian Football League (AFL) players, and determine outcomes regarding return to sport and injury recurrence. Retrospective cohort study. Elite AFL players with shoulder instability resulting in surgery were assessed in a retrospective cohort design (72 players/77 shoulders). Type of initial injury, surgical management, return to sport and injury recurrence were obtained. The mean follow-up period post-surgery was 2.9 years. Return to sport outcomes were compared between arthroscopic and open surgery using a Kaplan-Meier survival analysis. Logistic regression modelling was used to determine associations between injury recurrence, type of injury, participant age and method of surgery. Shoulder instability injuries occurred most frequently during tackling (40%). Arthroscopic surgery was preferred for primary shoulder instability. Nine (16%) recurrences occurred in those who underwent arthroscopic surgery compared to two (9%) following open surgery. Return to the elite level was slightly but significantly (2 weeks, p=0.049) longer for open compared to arthroscopic surgery. Recurrence was 5 times more likely if the primary injury was a dislocation and more likely in players who were younger at the time of surgery. Tackling was the predominant mechanism for shoulder instability injuries in AFL players and arthroscopic surgery was more commonly performed for primary injuries. Sustaining a dislocation as the primary injury and younger age increased the likelihood of recurrent instability. Careful consideration should be given to the operative management of these individuals. Copyright © 2017. Published by Elsevier Ltd.

Epidemiology of neurodegeneration in American-style professional football players.

Science.gov (United States)

Lehman, Everett J

2013-01-01

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

A Survey on Common Injuries in Recreational Badminton Players

Directory of Open Access Journals (Sweden)

A Muttalib

2009-11-01

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.

Female Chess Players Outperform Expectations When Playing Men.

Science.gov (United States)

Stafford, Tom

2018-03-01

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.

Motivational profile quality players handball

Directory of Open Access Journals (Sweden)

Alfonso Martínez Moreno

2017-06-01

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.

Game Performance Evaluation in Male Goalball Players

Science.gov (United States)

Molik, Bartosz; Morgulec-Adamowicz, Natalia; Kosmol, Andrzej; Perkowski, Krzysztof; Bednarczuk, Grzegorz; Skowroński, Waldemar; Gomez, Miguel Angel; Koc, Krzysztof; Rutkowska, Izabela; Szyman, Robert J

2015-01-01

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

Game Performance Evaluation in Male Goalball Players

Directory of Open Access Journals (Sweden)

Molik Bartosz

2015-12-01

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.

Kinanthropometric and performance characteristics of elite and non-elite female softball players.

Science.gov (United States)

Singh, S; Singh, M; Rathi, B

2013-12-01

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.

A Method for Using Player Tracking Data in Basketball to Learn Player Skills and Predict Team Performance.

Science.gov (United States)

Skinner, Brian; Guy, Stephen J

2015-01-01

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.

Physiological characteristics of elite soccer players.

Science.gov (United States)

Tumilty, D

1993-08-01

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.

Heart rate and activity profile for young female soccer players

OpenAIRE

Barbero Álvarez, José Carlos; Gómez López, Maite; Barbero Álvarez, Verónica; Granda Vera, Juan; Castagna, Carlo

2008-01-01

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...

Protective equipment use among female rugby players.

Science.gov (United States)

Comstock, R Dawn; Fields, Sarah K; Knox, Christy L

2005-07-01

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.

Investigating the Nutritional and Recovery Habits of Tennis Players

Directory of Open Access Journals (Sweden)

James A. Fleming

2018-04-01

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.

Investigating the Nutritional and Recovery Habits of Tennis Players.

Science.gov (United States)

Fleming, James A; Naughton, Robert J; Harper, Liam D

2018-04-03

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.

Knee and ankle osteoarthritis in former elite soccer players: A systematic review of the recent literature

NARCIS (Netherlands)

Kuijt, Marie-Therese K.; Inklaar, Han; Gouttebarge, Vincent; Frings-Dresen, Monique H. W.

2012-01-01

Objectives: To investigate the prevalence of knee and/or ankle osteoarthritis in former elite soccer player. Design: Systematic review. Methods: Medline, Embase and SPORTDiscus (2000 to January 2012) were used. To be included, studies were required to be a primary study, written in English, Dutch,

Time-motion analysis and physiological responses of small-sided team handball games in youth male players: Influence of player number

Directory of Open Access Journals (Sweden)

Jan Bělka

2016-12-01

Full Text Available Background: Effective training depends on knowledge of a sport's requirements. Small-sided games (SSG are a spontaneous form of specific training, where exercise intensity can be manipulated mainly by modifying external factors. In SSG the players develop technical and tactical skills in the similar situations, such as during a match and can also develop their physical skills. Objective: The purpose of this study was to examine the distance covered and physiological response of altering the number of youth male players during small-sided team handball games with modified rules. Methods: The subjects consisted of 12 male youth team handball players (age 16.6 ± 0.5 years playing the first league for youth male players in the Czech Republic. The study was conducted during six weeks (one training session per week. Only three SSG were played in each training session. The SSG were played, first with five players on each side (5 vs. 5, then four (4 vs. 4, then three (3 vs. 3. Each game was four minutes long, followed by three minutes of passive rest. Results: The players covered the greatest distance (520.6 ± 61.4 m in the SSG 3 vs. 3. There was a difference in the distance covered between players in the 3 vs. 3 SSG and the other SSG (4 vs. 4 and 5 vs. 5 (p = .041 and p = .043, respectively. In individual speed zones a difference occurred only in the first and third speed zone and always among the 3 vs. 3 and 5 vs. 5 SSG (p = .034 and p = .044, respectively. The highest average intensity (87.9 ± 4.8% HRmax was in 3 vs. 3 SSG. Loading of the players in 5 vs. 5 was lower compared to 4 vs. 4 (p = .035 and 3 vs. 3 (p < .001. There was a difference in zone load intensity (> 90% HRmax between 3 vs. 3 and 5 vs. 5 SSG (p = .041. Conclusions: These results indicate that changing the number of players during SSG with modified rules in youth team handball may be used to manipulate the physiological response

ANTHROPOMETRIC AND PHYSIOLOGICAL CHARACTERISTICS ON INDIAN INTERUNIVERSITY BASKETBALL PLAYERS

Directory of Open Access Journals (Sweden)

Shyamal Koley

2010-08-01

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.

Suitability of FIFA's "The 11" Training Programme for Young Football Players - Impact on Physical Performance.

Science.gov (United States)

Kilding, Andrew E; Tunstall, Helen; Kuzmic, Dejan

2008-01-01

There is a paucity of evidence regarding the use of injury prevention programmes for preadolescents participating in sport. "The 11 "injury prevention programme was developed by FIFA's medical research centre (F-MARC) to help reduce the risk of injury in football players aged 14 years and over. The aim of this study was to determine the suitability and effectiveness of "The 11 "for younger football players. Twenty-four [12 experimental (EXP), 12 control (CON)] young football players (age 10.4 ± 1.4 yr) participated. The EXP group followed "The 11 "training programme 5 days per week, for 6 weeks, completing all but one of the 10 exercises. Prior to, and after the intervention, both EXP and CON groups performed a battery of football-specific physical tests. Changes in performance scores within each group were compared using independent t-tests (p ≤ 0.05). Feedback was also gathered on the young players' perceptions of "The 11". No injuries occurred during the study in either group. Compliance to the intervention was 72%. Measures of leg power (3 step jump and counter-movement jump) increased significantly (3.4 and 6.0% respectively, p football players, for both physical development and potential injury prevention purposes, as well as to promote fair play. To further engage young football players in such a programme, some modification to "The 11 "should be considered. Key pointsChildren who participate in recreational and competitive sports, especially football, are susceptible to injury.There is a need for the design and assessment of injury prevention programmes for children.The 11 "improves essential physical performance characteristics and has the potential to reduce the risk of injury.It may be prudent to implement a 'child-friendly' version of "The 11", to enhance long-term programme adherence and to ensure progressive physical development of players.

Design of music player based on MCU STC12C5A60S2%一种基于51单片机的音乐播放器的设计

Institute of Scientific and Technical Information of China (English)

何谐; 唐大权; 张淑廷; 陈雪

2014-01-01

The hardware design method of the music player based on MCU STC12C5A60S2 is introduced in this paper. The program design of the music player based on principle of FAT32 file system is studied. In the music player, MCU STC12C5A60S2 is taken as a main controller,SD card as a memory medium of music files and VS1003 chip as a decoder unit. When the player is running,MCU STC12C5A60S2 reads the music file from the SD card and continuously transfers data flow to VS1003 for decoding. In the meantime,the OLED liquid crystal display shows the message of the music in real time. The tested results from experiments show the music player can play the music files in multiple formats fluently if the player is connected with ear phone.%主要介绍一种基于51单片机的音乐播放器的硬件设计方法，并研究在FAT32文件系统下音乐播放器的程序设计。该音乐播放器采用STC12C5A60S2单片机为主控制器，SD卡作为音乐文件的存储介质，VS1003芯片作为解码器。STC12C5A60S2单片机从 SD卡中读取音乐文件，并不断将数据流传送至VS1003解码，最后连接耳机播放，同时STC12C5A60S2连接OLED液晶显示屏实时显示音乐播放信息。实验表明，该音乐播放器连接耳机能流畅播放多种格式的音乐文件。

Race differences in ventricular remodeling and function among college football players.

Science.gov (United States)

Haddad, Francois; Peter, Shanon; Hulme, Olivia; Liang, David; Schnittger, Ingela; Puryear, Josephine; Gomari, Fatemeh A; Finocchiaro, Gherardo; Myers, Jonathan; Froelicher, Victor; Garza, Daniel; Ashley, Euan A

2013-07-01

Athletic training is associated with increases in ventricular mass and volume. Recent studies have shown that left ventricular mass increases proportionally in white athletes with a mass/volume ratio approaching unity. The objective of this study was to compare the proportionality in ventricular remodeling and ventricular function in black versus white National Collegiate Athletic Association Division I football players. From 2008 to 2011, football players at Stanford University underwent cardiovascular screening with a 12-point history and physical examination, electrocardiography, and focused echocardiography. Compared with white players, black players had on average higher left ventricular mass indexes (77 ± 11 vs 71 ± 11 g/m(2), p = 0.009), higher mass/volume ratios (1.18 ± 0.16 vs 1.06 ± 0.09 g/ml, p 1.2. Mass/volume ratio was inversely related to early diastolic tissue Doppler velocity e' (r = -0.50, p football players exhibit more concentric ventricular remodeling, lower early diastolic annular velocities, and increased ventricular voltage compared with white players. Ventricular mass increases proportionally to volume in white players but not in black players. Copyright © 2013 Elsevier Inc. All rights reserved.

Incidence and pattern of injuries among adolescent basketball players in Nigeria

OpenAIRE

Owoeye Oluwatoyosi Babatunde; Akodu Ashiyat; Oladokun Bayonle; Akinbo Sunday Rufus

2012-01-01

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...

No Relationship Between Hamstring Flexibility and Hamstring Injuries in Male Amateur Soccer Players: A Prospective Study.

Science.gov (United States)

van Doormaal, Mitchell C M; van der Horst, Nick; Backx, Frank J G; Smits, Dirk-Wouter; Huisstede, Bionka M A

2017-01-01

In soccer, although hamstring flexibility is thought to play a major role in preventing hamstring injuries, the relationship between hamstring flexibility and hamstring injuries remains unclear. To investigate the relationship between hamstring flexibility and hamstring injuries in male amateur soccer players. Case-control study; Level of evidence, 3. This study included 450 male first-class amateur soccer players (mean age, 24.5 years). Hamstring flexibility was measured by performing the sit-and-reach test (SRT). The relationship between hamstring flexibility and the occurrence of hamstring injuries in the following year, while adjusting for the possible confounding effects of age and previous hamstring injuries, was determined with a multivariate logistic regression analysis. Of the 450 soccer players, 21.8% reported a hamstring injury in the previous year. The mean (±SD) baseline score for the SRT was 21.2 ± 9.2 cm. During the 1-year follow-up period, 23 participants (5.1%) suffered a hamstring injury. In the multivariate analysis, while adjusting for age and previous injuries, no significant relationship was found between hamstring flexibility and hamstring injuries ( P = .493). In this group of soccer players, hamstring flexibility (measured with the SRT) was not related to hamstring injuries. Age and previous hamstring injuries as possible confounders did not appear to influence this relationship. Other etiological factors need to be examined to further elucidate the mechanism of hamstring injuries.

How to know and choose online games: differences between current and potential players.

Science.gov (United States)

Teng, Ching-I; Lo, Shao-Kang; Wang, Pe-Cheng

2007-12-01

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.

Teaching Beginning Trombone Players.

Science.gov (United States)

Fallis, Todd L.

2001-01-01

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)

Women's football: Player characteristics and demands of the game

Directory of Open Access Journals (Sweden)

Vanessa Martínez-Lagunas

2014-12-01

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

Cavum Septum Pellucidum in Retired American Pro-Football Players.

Science.gov (United States)

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

2016-01-01

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.

Algorithms for finding optimal paths in network games with p players

Directory of Open Access Journals (Sweden)

R. Boliac

1997-08-01

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.

Incidence of tinnitus in mp3 player users.

Science.gov (United States)

Figueiredo, Ricardo Rodrigues; Azevedo, Andreia Aparecida de; Oliveira, Patrícia Mello de; Amorim, Sandro Pereira Vasconcellos; Rios, Artur Guedes; Baptista, Vanderlei

2011-06-01

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.

Incidence of and risk factors for traumatic anterior shoulder dislocation: an epidemiologic study in high-school rugby players.

Science.gov (United States)

Kawasaki, Takayuki; Ota, Chihiro; Urayama, Shingo; Maki, Nobukazu; Nagayama, Masataka; Kaketa, Takefumi; Takazawa, Yuji; Kaneko, Kazuo

2014-11-01

The incidence of reinjuries due to glenohumeral instability and the major risk factors for primary anterior shoulder dislocation in youth rugby players have been unclear. The purpose of this study was to investigate the incidence, mechanisms, and intrinsic risk factors of shoulder dislocation in elite high-school rugby union teams during the 2012 season. A total of 378 male rugby players from 7 high-school teams were investigated by use of self-administered preseason and postseason questionnaires. The prevalence of a history of shoulder dislocation was 14.8%, and there were 21 events of primary shoulder dislocation of the 74 overall shoulder injuries that were sustained during the season (3.2 events per 1000 player-hours of match exposure). During the season, 54.3% of the shoulders with at least one episode of shoulder dislocation had reinjury. This study also indicated that the persistence of glenohumeral instability might affect the player's self-assessed condition, regardless of the incidence during the current season. By a multivariate logistic regression method, a history of shoulder dislocation on the opposite side before the season was found to be a risk factor for contralateral primary shoulder dislocation (odds ratio, 3.56; 95% confidence interval, 1.27-9.97; P = .02). High-school rugby players with a history of shoulder dislocation are not playing at full capacity and also have a significant rate of reinjury as well as a high risk of dislocating the other shoulder. These findings may be helpful in deciding on the proper treatment of primary anterior shoulder dislocation in young rugby players. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Pilot study of female high school basketball players' anterior cruciate ligament injury knowledge, attitudes, and practices.

Science.gov (United States)

Iversen, M D; Friden, C

2009-08-01

An anterior cruciate ligament (ACL) injury prevention program was evaluated. One hundred and thirteen female high school varsity and junior varsity basketball players and 12 coaches participated in an 8-week educational and skills program. Demographic and injury history data were collected. At pre-intervention and at the end of season, knowledge, attitudes, and practices about ACL risk and injury prevention were assessed via questionnaires, and frequency of two-footed landings were videotaped during games. Univariate statistics described the sample. Paired t-tests evaluated the program's impact. Cronbach's alpha, correlations, and kappa statistics assessed the validity and reliability of questionnaires and video analysis. Of the 113 players, 74 completed the study. The players' mean age was 16.25 years (SD=1.07; range=14.2-18.8). Baseline knowledge score was 57.2%, practice 58.4%, and attitude 73.5%. The mean baseline knowledge score of the 12 coaches (mean age=40.8 years; SD=10.3; range=26.9-56.3) was 68.7%. Players' knowledge about ACL injury prevention improved (t=2.57; P<0.01). No changes in attitudes toward injury prevention were found (t(diff)=1.88; P<0.06). Inter-rater reliability of two-footed landings observed was acceptable (kappa=0.72). Videotape analyses revealed a 5.5% increase in landing performance (t(diff)=9.6; P<0.0001). The program increased knowledge about ACL injury risk and improved player's landing skills.

A Method for Using Player Tracking Data in Basketball to Learn Player Skills and Predict Team Performance.

Directory of Open Access Journals (Sweden)

Brian Skinner

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.

Nutritional Habits & Knowledge in the Division I Collegiate Football Player

OpenAIRE

Hale, Mallory

2013-01-01

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 ...

Strength asymmetry of the shoulders in elite volleyball players.

Science.gov (United States)

Hadzic, Vedran; Sattler, Tine; Veselko, Matjaž; Markovic, Goran; Dervisevic, Edvin

2014-01-01

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

Mental Fatigue and Spatial References Impair Soccer Players' Physical and Tactical Performances

Directory of Open Access Journals (Sweden)

Diogo Coutinho

2017-09-01

Full Text Available This study examined the effects of mental fatigue and additional corridor and pitch sector lines on players' physical and tactical performances during soccer small-sided games. Twelve youth players performed four Gk+6vs6+Gk small-sided games. Prior to the game, one team performed a motor coordination task to induce mental fatigue, while the other one performed a control task. A repeated measures design allowed to compare players' performances across four conditions: (a with mental fatigue against opponents without mental fatigue in a normal pitch (MEN, (b with mental fatigue on a pitch with additional reference lines (#MEN; (c without mental fatigue against mentally fatigued opponents on a normal pitch (CTR; and (d without mental fatigue on a pitch with reference lines (#CTR. Player's physical performance was assessed by the distance covered per minute and the number of accelerations and decelerations (0.5–3.0 m/s2; > −3.0 m/s2. Positional data was used to determine individual (spatial exploration index, time synchronized in longitudinal and lateral directions and team-related variables (length, width, speed of dispersion and contraction. Unclear effects were found for the physical activity measures in most of the conditions. There was a small decrease in time spent laterally synchronized and a moderate decrease in the contraction speed when MEN compared to the CTR. Also, there was a small decrease in the time spent longitudinally synchronized during the #MEN condition compared to MEN. The results showed that mental fatigue affects the ability to use environmental information and players' positioning, while the additional reference lines may have enhanced the use of less relevant information to guide their actions during the #MEN condition. Overall, coaches could manipulate the mental fatigue and reference lines to induce variability and adaptation in young soccer players' behavior.

MP3 Players and Hearing Loss: Adolescents' Perceptions of Loud Music and Hearing Conservation

NARCIS (Netherlands)

Vogel, I.; Brug, J.; Hosli, E.J.; Ploeg, C.P.B. van der; Raat, H.

2008-01-01

Objective: To explore adolescents' behaviors and opinions about exposure to loud music from MP3 players. Study design: We conducted a qualitative analysis of focus-group discussions with adolescents aged 12 to 18 years from 2 large secondary schools (1 urban and 1 rural) for pre-vocational and

Evaluation of functional limitations in female soccer players and their relationship with sports level--a cross sectional study.

Directory of Open Access Journals (Sweden)

Monika Grygorowicz

Full Text Available THE MAIN OBJECTIVES OF THE STUDY: the aim of this study was to analyze: a abnormalities in the length of lower limb muscles, b the correctness of movement patterns, and c the impact of functional limitations of muscles on the correctness of fundamental movement patterns in a group of female soccer players, in relation to their skill level. MATERIALS AND METHODS: 21 female soccer players from Polish Ekstraklasa and 22 players from the 1(st Division were tested for lower limb muscle length restrictions and level of fundamental movement skills (with the Fundamental Movement Screen™ test concept by Gray Cook. Chi-square test was used for categorical unrelated variables. Differences between groups in absolute point values were analyzed using the non-parametric Mann-Whitney U test. Statistical significance was set at p<0.05. RESULTS: Statistically significant higher number of measurements indicating an abnormal length of rectus femoris was observed in the 1st Division group (p = 0.0433. In the group of Ekstraklasa the authors obtained a significantly higher number of abnormal hamstring test results (p = 0.0006. Ekstraklasa players scored higher in the rotational stability test of the trunk (p = 0.0008, whereas the 1st Division players scored higher in the following tests: deep squat (p = 0.0220, in-line lunge (p = 0.0042 and active straight leg raise (p = 0.0125. The results suggest that there are different functional reasons affecting point values obtained in the FMS™ tests in both analyzed groups. CONCLUSIONS: The differences in the flexibility of rectus femoris and hamstring muscle observed between female soccer players with different levels of training, may result from a long-term impact of soccer training on the muscle-tendon system and articular structures. Different causes of abnormalities in fundamental movement patterns in both analyzed groups suggest the need for tailoring prevention programs to the level of sport

Prevalence and variance of shoulder injuries in elite collegiate football players.

Science.gov (United States)

Kaplan, Lee D; Flanigan, David C; Norwig, John; Jost, Patrick; Bradley, James

2005-08-01

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

An Analysis of Futsal Players' Self-Esteem Levels

Science.gov (United States)

Kocak, Mehmet

2015-01-01

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…

The epidemiology of 1345 shoulder dislocations and subluxations in French Rugby Union players: a five-season prospective study from 2008 to 2013.

Science.gov (United States)

Bohu, Yoann; Klouche, Shahnaz; Lefevre, Nicolas; Peyrin, Jean-Claude; Dusfour, Bernard; Hager, Jean-Philippe; Ribaut, Aurélie; Herman, Serge

2015-12-01

An understanding of the epidemiology of shoulder dislocation/subluxation in rugby union players could help develop targeted prevention programmes and treatment. We performed a multiyear epidemiological survey of shoulder dislocation/subluxation in a large cohort of rugby players. A descriptive epidemiological study was performed prospectively for five playing seasons (2008-2013) in all players licensed in the French Rugby Union. Rugby players were categorised into five groups by age. The player and the team physician reported the injury to the club insurance company if it occurred during training or a match. The goals of the study were to define the rate, type and causes of shoulder dislocation/subluxation. 88,044 injuries were reported, including 1345 (1.5%) episodes of dislocation/subluxation in 1317 men and 28 women, mean age 22.5±5.9 years. About 10/10,000 men and 5/10,000 women reported an episode of shoulder dislocation/subluxation per season, including 83/10,000 senior professionals, 17/10,000 senior amateurs, 21/10,000 juniors, 12/10,000 cadets and rugby school players. Shoulder dislocation/subluxation was significantly more frequent in senior and junior players (prugby players with a history of shoulder dislocation/subluxation should receive special attention from sports medicine professionals and orthopaedic surgeons. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Perceptions of football players regarding injury risk factors and prevention strategies.

Directory of Open Access Journals (Sweden)

Astrid Zech

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.

Cervical isometric strength and range of motion of elite rugby union players: a cohort study.

Science.gov (United States)

Hamilton, David F; Gatherer, Don

2014-01-01

Head and neck injury is relatively common in Rugby Union. Despite this, strength and range-of-motion characteristics of the cervical spine are poorly characterised. The aim of this study was to provide data on the strength and range-of-motion of the cervical spine of professional rugby players to guide clinical rehabilitation. A cohort study was performed evaluating 27 players from a single UK professional rugby club. Cervical isometric strength and range-of-motion were assessed in 3 planes of reference. Anthropometric data was collected and multivariate regression modelling performed with a view to predicting cervical isometric strength. Largest forces were generated in extension, with broadly equal isometric side flexion forces at around 90% of extension values. The forwards generated significantly more force than the backline in all parameters bar flexion. The forwards had substantially reduced cervical range-of-motion and larger body mass, with differences observed in height, weight, neck circumference and chest circumference (p isometric extension (adjusted R(2) = 30.34). Rehabilitative training programs aim to restore individuals to pre-injury status. This work provides reference ranges for the strength and range of motion of the cervical spine of current elite level rugby players.

Incidence of injuries in high school softball and baseball players.

Science.gov (United States)

Shanley, Ellen; Rauh, Mitchell J; Michener, Lori A; Ellenbecker, Todd S

2011-01-01

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.

Childhood football play and practice in relation to self-regulation and national team selection; a study of Norwegian elite youth players.

Science.gov (United States)

Erikstad, Martin K; Høigaard, Rune; Johansen, Bjørn Tore; Kandala, Ngianga-Bakwin; Haugen, Tommy

2018-03-09

Childhood sport participation is argued to be important to understand differences in self-regulation and performance level in adolescence. This study sought to investigate if football-specific activities in childhood (6-12 years of age) is related to self-regulatory skills and national under 14- and 15-team selection in Norwegian elite youth football. Data of practice histories and self-regulatory skills of 515 youth football players selected at Norwegian regional level were collected and further analysed using multilevel analyses. The results revealed that high self-regulated players were more likely to be selected for national initiatives, and increased their involvement in peer-led football practice and adult-led football practice during childhood, compared to players with lower levels of self-regulation. While national level players reported higher levels of peer-led football play in childhood, the interaction effect suggest that the regional level players increased their involvement in peer-led play during childhood compared to national level players. In conclusion, the findings indicate that childhood sport participation may contribute to later differences in self-regulation, and highlights the importance of childhood engagement in football-specific play and practice in the development of Norwegian youth football players.

Match activities of elite women soccer players at different performance levels

DEFF Research Database (Denmark)

Mohr, Magni; Krustrup, Peter; Andersson, Helena

2008-01-01

, (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...

Physical Characteristics and Performance of Japanese Top-Level American Football Players.

Science.gov (United States)

Yamashita, Daichi; Asakura, Masaki; Ito, Yoshihiko; Yamada, Shinzo; Yamada, Yosuke

2017-09-01

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.

Self-Esteem Profile among the Female Futsal-Football Players at Jordanian Clubs

Science.gov (United States)

Khasawneh, Aman

2015-01-01

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,…

Talented football players' development of achievement motives, volitional components, and self-referential cognitions: A longitudinal study.

Science.gov (United States)

Feichtinger, Philip; Höner, Oliver

2015-01-01

Adolescence is regarded as a key developmental phase in the course of talented football players' careers. The present study focuses on early adolescent players' development of achievement motives, volitional components, and self-referential cognitions. Based on the multidimensional and dynamic nature of talent, the development of multifaceted personality characteristics is an important issue in the context of sports talent research. According to previous findings in psychology, personality characteristics' development is defined by both stability and change, and the current study analyses four different types: differential stability (I), mean-level change (II), individual-level change (III), and structural stability (IV). The sample consists of 151 male players in the talent development programme of the German Football Association. Psychological diagnostics of the personality characteristics are implemented across longitudinal sections over a time period of three seasons, from the U12 to U14 age classes. The results reveal that the personality characteristics show (I) moderate test-retest correlations over one-year intervals (.43 ≤ rtt ≤ .62), and lower coefficients for a two-year period (.26 ≤ rtt ≤ .53). (II) Most of the personality characteristics' mean values differ significantly across the age classes with small effect sizes (.01 ≤ [Formula: see text] ≤ .03). (III) Only minor individual-level changes in the football players' development are found. (IV) The personality characteristics' associations within a two-factor structure do not stay invariant over time. From the results of the present study, conclusions are drawn regarding the talent identification and development process.

Personality traits and life satisfaction among online game players.

Science.gov (United States)

Chen, Lily Shui-Lien; Tu, Hill Hung-Jen; Wang, Edward Shih-Tse

2008-04-01

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.

Goal orientations, beliefs about success, and performance improvement among young elite Dutch soccer players

NARCIS (Netherlands)

Van Yperen, Nico W.; Duda, Joan L.

1999-01-01

Extending past work testing goal perspective theory in sport, one purpose of this study was to examine, via a longitudinal design, the relationship of goal orientations to the beliefs about the causes of success in the case of elite male Dutch soccer players. A second purpose was to determine the

How should "hot" players in basketball be defended? The use of fast-and-frugal heuristics by basketball coaches and players in response to streakiness.

Science.gov (United States)

Csapo, Peter; Avugos, Simcha; Raab, Markus; Bar-Eli, Michael

2015-01-01

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.

Effect of Core Training on 16 Year-Old Soccer Players

Science.gov (United States)

Afyon, Yakup Akif

2014-01-01

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…

Chess players' fame versus their merit.

Science.gov (United States)

Simkin, M V; Roychowdhury, V P

2015-12-12

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.

Between-game variation of physical soccer performance measures in highly trained youth soccer players.

Science.gov (United States)

Doncaster, Greg; Unnithan, Viswanath

2017-07-12

To assess the between-game variation in measures of physical performance during 11 v 11 soccer match-play, over a short period of time, in highly trained youth soccer players. A single cohort observational study design was employed. Physical match performance data were collected from 17 male, highly trained youth soccer players (age: 13.3 ± 0.4 y) over three, 2 x 20min, 11 v 11 matches. Using 10 Hz GPS, the variables selected for analyses were total distance (TD), high-speed running (HSR), very high-speed running (VHSR), number of high-speed running efforts (HSReff) and number of very high-speed running efforts (VHSReff). Match data was also separated into cumulative 5 min epochs, to identify the peak 5 min epoch and the mean of the cumulative 5 min epochs for each match. Variability was quantified using the coefficient of variation (CV), Standard error of measurement (SEM) and intra-class correlation coefficient (ICC). Between- and within-player smallest worthwhile changes (SWC) were also calculated for each variable to aid in the interpretation of the data. Analysis of the variance between games reported a low CV for TD (3.8%) but larger CVs for HSR (33.3%), HSReff (35.4%) and VHSR and VHSReff (59.6 and 57.4 %, respectively). Analysis of 5 min epochs (peak and average) found an increase in the CVs beyond that of the values reported for the whole match. Between-player SWC in high intensity physical performance data ranged from 24.7 - 42.4 %, whereas within-player SWC ranged from 1.2 - 79.9%. The between-game variability of high and very high intensity activities in youth soccer players, across three soccer matches over a short period of time (2 weeks), is relatively 'large' and specific to the individual, thus highlighting the need for caution when interpreting physical performance data between games and players.

Sprint profile of professional female soccer players during competitive matches: Female Athletes in Motion (FAiM) study.

Science.gov (United States)

Vescovi, Jason D

2012-01-01

The aim of this study was to determine sprint profiles of professional female soccer players and evaluate how various speed thresholds impact those outcomes. Seventy-one professional players competing in full matches were assessed repeatedly during 12 regular season matches using a Global Positioning System (GPS). Locomotion ≥18 km · h⁻¹ was defined as sprinting and each event was classified into: Zone 1: 18.0-20.9 km· h⁻¹; Zone 2: 21.0-22.9 km · h⁻¹; Zone 3: 23.0-24.9 km · h⁻¹ and Zone 4: >25 km · h⁻¹. Outcomes included: duration (s), distance (m), maximum speed (km · h⁻¹), duration since previous sprint (min) and proportion of total sprint distance. In total 5,019 events were analysed from 139 player-matches. Mean sprint duration, distance, maximum speed and time between sprints were 2.3 ± 1.5 s, 15.1 ± 9.4 m, 21.8 ± 2.3 km· h⁻¹, and 2.5 ± 2.5 min, respectively. Mean sprint distances were 657 ± 157, 447 ± 185, and 545 ± 217 m for forwards, midfielders and defenders, respectively (P ≤ 0.046). Midfielders had shorter sprint duration (P = 0.023), distance (P ≤ 0.003) and maximum speed (P professional female soccer players covered 5.3 ± 2.0% of total distance ≥18 km · h⁻¹ with positional differences and percent decrements distinct from other previously identified elite players. These data should guide the development of high intensity and sprint thresholds for elite-standard female soccer players.

DIFFERENCES IN FUNCTIONAL AND MOTOR ABILITIES OFYOUNG FOOTBALL PLAYERS, BASKETBALL AND VOLLEYBALL PLAYERS

Directory of Open Access Journals (Sweden)

Franja Fratrić

2009-11-01

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.

Soccer and Relative Age Effect: A Walk among Elite Players and Young Players

Directory of Open Access Journals (Sweden)

Manuel Jacob Sierra-Díaz

2017-01-01

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.

Sex-specific differences in injury types among basketball players

OpenAIRE

Ito E; Iwamoto J; Azuma K; Matsumoto H

2014-01-01

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...

Linking performance decline to choking: players' perceptions in basketball.

Science.gov (United States)

Fryer, Ashley Marie; Tenenbaum, Gershon; Chow, Graig M

2018-02-01

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.

Differences in energy capacities between tennis players and runners.

Science.gov (United States)

Novak, Dario; Vucetić, Vlatko; Zugaj, Sanja

2013-05-01

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.

Fitness Profiles of Elite Portuguese Rugby Union Players

Science.gov (United States)

Vaz, Luís; Morais, Tomaz; Rocha, Henrique; James, Nic

2014-01-01

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

Fitness Profiles of Elite Portuguese Rugby Union Players

Directory of Open Access Journals (Sweden)

Vaz Luís

2014-07-01

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.

Shoulder pain -- a common problem in world-class badminton players.

Science.gov (United States)

Fahlström, Martin; Yeap, Joo Seng; Alfredson, Håkan; Söderman, Kerstin

2006-06-01

Badminton is a sport that requires a lot of over-shoulder motion, with the shoulder in abduction/external rotation. This questionnaire study on 188 international top-level badminton players during the World Mixed Team Championships showed that previous or present shoulder pain on the dominant side was reported by 52% of the players. Previous shoulder pain was reported by 37% of the players and on-going shoulder pain by 20% of the players. There were no significant differences in the prevalence of shoulder pain between men and women. The majority of the shoulder pain had started gradually. The pain was usually associated with shoulder activity, and stiffness was a common, associated symptom. Furthermore, the shoulder pain was associated with consequences such as sleeping disturbances, changes in training and competition habits, and it also affected activities of daily living. The majority of the players had sought medical advice and had been given different kinds of treatment. The study showed that shoulder pain is a common and significant problem in world-class badminton players, and the consequences are most likely of importance for their training and playing capacity.

Noise effects in a three-player prisoner's dilemma quantum game

International Nuclear Information System (INIS)

Ramzan, M; Khan, M K

2008-01-01

We study the three-player prisoner's dilemma game under the effect of decoherence and correlated noise. It is seen that the quantum player is always better off than the classical players. It is also seen that the game's Nash equilibrium does not change in the presence of correlated noise in contradiction to the effect of decoherence in the multiplayer case. Furthermore, it is shown that for maximum correlation the game does not behave as a noiseless game and the quantum player is still better off for all values of the decoherence parameter p which is not possible in the two-player case. In addition, the payoffs reduction due to decoherence is controlled by the correlated noise throughout the course of the game

Attributes of top elite team-handball players.

Science.gov (United States)

Massuça, Luís M; Fragoso, Isabel; Teles, Júlia

2014-01-01

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.

Biomechanics of Heading a Soccer Ball: Implications for Player Safety

Directory of Open Access Journals (Sweden)

Charles F. Babbs

2001-01-01

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.

The architecture of the chess player's brain.

Science.gov (United States)

Hänggi, Jürgen; Brütsch, Karin; Siegel, Adrian M; Jäncke, Lutz

2014-09-01

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.

Mechanizing Exploratory Game Design

OpenAIRE

Smith, Adam Marshall

2012-01-01

Game design is an art form that deals with inherently interactive artifacts. Game designers craft games (assembled from rule systems and content), but they really seek to manipulate play: the interaction between games and players. When developing new games that are similar to past games, a designer may rely on previous experience with related designs and relatively easy access to players familiar with conventional design choices. When exploratorily venturing into uncharted territory, uncoveri...

Laterality of the legs in young female soccer players

Directory of Open Access Journals (Sweden)

Antosiak-Cyrak Katarzyna Z.

2015-12-01

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.

Mental Toughness Attributes of Junior Level Medalist Badminton Players

Directory of Open Access Journals (Sweden)

Varghese C. Antony

2016-10-01

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

Game Coaching System Design and Development: A Retrospective Case Study of FPS Trainer

Science.gov (United States)

Tan, Wee Hoe

2013-01-01

This paper is a retrospective case study of a game-based learning (GBL) researcher who cooperated with a professional gamer and a team of game developers to design and develop a coaching system for First-Person Shooter (FPS) players. The GBL researcher intended to verify the ecological validity of a model of cooperation; the developers wanted to…

Days to Return to Participation After a Hamstrings Strain Among American Collegiate Soccer Players

Science.gov (United States)

Cross, Kevin M.; Saliba, Susan A.; Conaway, Mark; Gurka, Kelly K.; Hertel, Jay

2015-01-01

Context Among US collegiate soccer players, the incidence rate and the event characteristics of hamstrings strains differ between sexes, but comparisons in the return-to-participation (RTP) time have not been reported. Objective To compare the RTP time between male and female collegiate soccer players and analyze the influence of event characteristics on the RTP time for each sex. Design Descriptive epidemiology study. Setting Data were collected from collegiate teams that voluntarily participated in the National Collegiate Athletic Association Injury Surveillance System. Patients or Other Participants Collegiate soccer athletes who sustained 507 hamstrings strains (306 men, 201 women) during the 2004 through 2009 fall seasons. Main Outcome Measure(s) Nonparametric statistics were used to evaluate RTP time differences between sexes and among categories of each event characteristic (ie, time of season, practice or competition, player position). Negative binomial regression was used to model the RTP time for each sex. All analyses were performed separately for first-time and recurrent strains. Results We found no differences in the RTP time between sexes for first-time (median: men = 7.0 days, women = 6.0 days; P = .07) or recurrent (median: men = 11 days, women = 5.5 days; P = .06) hamstrings strains. For male players with first-time strains, RTP time was increased when the strain occurred during competition or the in-season/postseason and varied depending on the division of play. Among female players with first-time strains, we found no differences in RTP time within characteristics. For male players with recurrent hamstrings strains, the RTP time was longer when the injury occurred during the in-season/postseason. Among female players with recurrent strains, RTP time was longer for forwards than for midfielders or defenders. Conclusions Although we found no differences in the RTP time after hamstrings strains in male and female collegiate soccer players, each sex

Associations between abnormal ultrasound color Doppler measures and tendon pain symptoms in badminton players during a season: a prospective cohort study.

Science.gov (United States)

Boesen, Anders Ploug; Boesen, Morten Ilum; Torp-Pedersen, Soren; Christensen, Robin; Boesen, Lars; Hölmich, Per; Nielsen, Michael Bachmann; Koenig, Merete Juhl; Hartkopp, Andreas; Ellegaard, Karen; Bliddal, Henning; Langberg, Henning

2012-03-01

Color Doppler ultrasound is widely used to examine intratendinous flow in individuals with overuse tendon problems, but the association between color Doppler and pain is still unclear. Intratendinous flow is present and associated with pain in badminton players, and intratendinous flow and pain increase during a badminton season. Cohort study (prognosis); Level of evidence, 2. Ninety-five semiprofessional badminton players were included in the study at a tournament at the start of the badminton season. All players were interviewed regarding pain. The anterior knee tendons and Achilles tendons were studied. Each tendon was scored using a quantitative grading system (grades 0-5) and a qualitative scoring system (color fraction) using color Doppler ultrasound. Eight months later, 86 of the players (91%) were retested by the same investigators during an equivalent badminton tournament (including 1032 tendon regions; 86 players with 4 tendons each with 3 regions), thus forming the study group. At the start of the season, 24 players (28%) experienced pain in 37 tendons (11%), and at the end of the season, 31 players (36%) experienced pain in 51 tendons (15%), which was a statistically significant increase (P = .0002). Abnormal flow was found in 230 tendon regions in 71 players (83%) at the start of the season compared with 78 tendon regions in 41 players (48%) at the follow-up. The decrease in abnormal flow was statistically significant (P < .0001). Of the 37 painful tendons at the start of the season, 25 had abnormal flow (68%). In contrast, 131 tendons (85%) with abnormal flow at the start of the season were pain free. At the end of the season, 18 of the 51 painful tendons (35%) had abnormal flow. Ninety-six of the 131 pain-free tendons (73%) with abnormal flow at the start of the season were normalized (no pain and normal flow) at the end of the season. It was not possible to verify any association between intratendinous flow and pain at the start of the season or at

Cardiac dimensions and function in female handball players.

Science.gov (United States)

Malmgren, A; Dencker, M; Stagmo, M; Gudmundsson, P

2015-04-01

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.

Energy and macronutrient intakes of professional football (soccer) players.

OpenAIRE

Maughan, R J

1997-01-01

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...

Enhancing physical performance in male volleyball players with a caffeine-containing energy drink.

Science.gov (United States)

Del Coso, Juan; Pérez-López, Alberto; Abian-Vicen, Javier; Salinero, Juan Jose; Lara, Beatriz; Valadés, David

2014-11-01

There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P volleyball players.

Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain: An Assessor-Blinded Comparison.

Science.gov (United States)

Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

2014-02-01

Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Cross-sectional study; Level of evidence, 3. Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Large eccentric hip adduction strength deficits were found in soccer players with adductor-related groin pain compared with asymptomatic soccer players, while no isometric

ANTHROPOMETRIC AND MOTOR CHARACTERISTICS IN VOLLEYBALL AND BASKETBALL PLAYERS

Directory of Open Access Journals (Sweden)

Enver Tahiraj

2011-09-01

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

THE EFFECT OF MODERATE AND HIGH-INTENSITY FATIGUE ON GROUNDSTROKE ACCURACY IN EXPERT AND NON-EXPERT TENNIS PLAYERS

Directory of Open Access Journals (Sweden)

Mark Lyons

2013-06-01

Full Text Available Exploring the effects of fatigue on skilled performance in tennis presents a significant challenge to the researcher with respect to ecological validity. This study examined the effects of moderate and high-intensity fatigue on groundstroke accuracy in expert and non-expert tennis players. The research also explored whether the effects of fatigue are the same regardless of gender and player's achievement motivation characteristics. 13 expert (7 male, 6 female and 17 non-expert (13 male, 4 female tennis players participated in the study. Groundstroke accuracy was assessed using the modified Loughborough Tennis Skills Test. Fatigue was induced using the Loughborough Intermittent Tennis Test with moderate (70% and high-intensities (90% set as a percentage of peak heart rate (attained during a tennis-specific maximal hitting sprint test. Ratings of perceived exertion were used as an adjunct to the monitoring of heart rate. Achievement goal indicators for each player were assessed using the 2 x 2 Achievement Goals Questionnaire for Sport in an effort to examine if this personality characteristic provides insight into how players perform under moderate and high-intensity fatigue conditions. A series of mixed ANOVA's revealed significant fatigue effects on groundstroke accuracy regardless of expertise. The expert players however, maintained better groundstroke accuracy across all conditions compared to the novice players. Nevertheless, in both groups, performance following high-intensity fatigue deteriorated compared to performance at rest and performance while moderately fatigued. Groundstroke accuracy under moderate levels of fatigue was equivalent to that at rest. Fatigue effects were also similar regardless of gender. No fatigue by expertise, or fatigue by gender interactions were found. Fatigue effects were also equivalent regardless of player's achievement goal indicators. Future research is required to explore the effects of fatigue on

Upper extremity sensorimotor control among collegiate football players.

Science.gov (United States)

Laudner, Kevin G

2012-03-01

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.

Body Image Amongst Elite Rugby Union Players.

Science.gov (United States)

Gibson, Claire; Hindle, Chloe; McLay-Cooke, Rebecca; Slater, Joanne; Brown, Rachel; Smith, Brett; Baker, Dane; Healey, Philip; Black, Katherine

2017-11-16

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.

Self-Regulation of Practice Behavior Among Elite Youth Soccer Players : An Exploratory Observation Study

NARCIS (Netherlands)

Toering, Tynke; Elferink-Gemser, Marije; Jordet, Geir; Jorna, Casper; Pepping, Gert-Jan; Visscher, Chris

2011-01-01

This study aimed to measure behavioral correlates of self-regulation in elite youth soccer players. Behaviors regarded as indicative of self-regulated learning were identified by interviewing six expert youth soccer coaches. These behaviors were observed during practice of eight elite youth soccer

CAREER TRANSITION FROM JUNIOR TO SENIOR IN BASKETBALL PLAYERS

Directory of Open Access Journals (Sweden)

Alberto Lorenzo

2009-01-01

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.

The Physiological Profile of Junior Soccer Players at SSBB Surabaya Bhakti

Science.gov (United States)

Nashirudin, M.; Kusnanik, N. W.

2018-01-01

Soccer players are required to have good physical fitness in order to achieve optimum accomplishment; physical fitness stands as the foundation of technical and tactical proficiency as well as the mental maturity during the matches. The purpose of this study was to identify the physiological profile of junior soccer players of SSB Surabaya Bhakti age 16-17. The research was conducted at 20 junior soccer players. This research was quantitative with descriptive analysis. Data were collected by testing of physiological (anaerobic power and capacity including explosive leg power, speed, agility; aerobic capacity: cardiovascular endurance). Data was analyzed using percentage. The result showed that the percentage of explosive leg power of junior soccer players were 30% (good category), speed was 85% (average category), right agility was 90% (average category), left agility was 75% (average category). On the other hand, the aerobic power and capacity of the junior soccer players in this study was 50% (average category). The conclusion of this research is that the physiological profile of junior soccer players at SSB Surabaya Bhakti age 16-17 was majority in average category.

Motivation and Sport Injuries in Handball Players

Directory of Open Access Journals (Sweden)

Laguna, María

2010-12-01

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.

Using network metrics to investigate football team players' connections: A pilot study

Directory of Open Access Journals (Sweden)

Filipe Manuel Clemente

2014-09-01

Full Text Available The aim of this pilot study was propose a set of network methods to measure the specific properties of football teams. These metrics were organized on "meso" and "micro" analysis levels. Five official matches of the same team on the First Portuguese Football League were analyzed. An overall of 577 offensive plays were analyzed from the five matches. From the adjacency matrices developed per each offensive play it were computed the scaled connectivity, the clustering coefficient and the centroid significance and centroid conformity. Results showed that the highest values of scaled connectivity were found in lateral defenders and central and midfielder players and the lowest values were found in the striker and goalkeeper. The highest values of clustering coefficient were generally found in midfielders and forwards. In addition, the centroid results showed that lateral and central defenders tend to be the centroid players in the attacking process. In sum, this study showed that network metrics can be a powerful tool to help coaches to understanding the specific team's properties, thus supporting decision-making and improving sports training based on match analysis.

Adapting playware to multiple players

DEFF Research Database (Denmark)

Þorsteinsson, Arnar Tumi; Lund, Henrik Hautop; Mastorakis, Nikos

2011-01-01

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...

A Comparative Study on the Bidding Behavior of Pay as Bid and Uniform Price Electricity Market Players

DEFF Research Database (Denmark)

Haji Bashi, Mazaher; Khazraj, Hesam; Bak, Claus Leth

2018-01-01

High prices are expected for high demand times in the electricity markets and vice versa. The System Capacity Margin (SCM) demonstrates the abundance of electricity in the market. Naturally, higher SCM causes to lower price but, the players' behavior distortions have been frequently addressed...... in the literature. The overall producers’ bidding behaviors participating in Iran Electricity Market (IEM) as the low wind penetrated case and the Danish Electricity Market (DEM) as a high wind penetrated case are studied in this paper. An index is introduced to describe the overall market players’ behaviors....... Considering the players' behavior and using adaptive Neuro-fuzzy inference system, a model is derived. Although the total trend of prices is descending while the SCM increases, the results show some unexpected behaviors in IEM. Finally, players' biding behavior are compared in DEM and IEM. Markov transition...

Analysis of the Motor Activities of Professional Polish Soccer Players

Directory of Open Access Journals (Sweden)

Andrzejewski Marcin

2016-12-01

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.

A Study on In-Match Rugby Coaches' Communications with Players: A Holistic Approach

Science.gov (United States)

Mouchet, Alain; Harvey, Stephen; Light, Richard

2014-01-01

Background: While there is significant interest in coach behaviour during training sessions and recognition of what it could add to existing knowledge on coaching, in-game coach behaviour has received little attention. Purpose: The purpose of this study was to identify coaches' in-competition communications with rugby players, through a series of…

Speed and countermovement-jump characteristics of elite female soccer players, 1995-2010.

Science.gov (United States)

Haugen, Thomas A; Tønnessen, Espen; Seiler, Stephen

2012-12-01

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.

Brain damage in former association football players

International Nuclear Information System (INIS)

Sortland, O.; Tysvaer, A.T.

1989-01-01

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.)

Skeletal muscle and performance adaptations to high-intensity training in elite male soccer players

DEFF Research Database (Denmark)

Fransson, Dan; Nielsen, Tobias Schmidt; Olsson, Karl

2018-01-01

PURPOSE: To examine the skeletal muscle and performance responses across two different exercise training modalities which are highly applied in soccer training. METHODS: Using an RCT design, 39 well-trained male soccer players were randomized into either a speed endurance training (SET; n = 21...... pronouncedly than small-sided game training, but comparable responses were in muscle ion transporters and antioxidative capacity in well-trained male soccer players....

Structure constrained by metadata in networks of chess players.

Science.gov (United States)

Almeira, Nahuel; Schaigorodsky, Ana L; Perotti, Juan I; Billoni, Orlando V

2017-11-09

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.

Athletic performance outcomes following lumbar discectomy in professional basketball players.

Science.gov (United States)

Anakwenze, Okechukwu A; Namdari, Surena; Auerbach, Joshua D; Baldwin, Keith; Weidner, Zachary D; Lonner, Baron S; Huffman, G R; Sennett, Brian J

2010-04-01

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

Injuries in Japanese Mini-Basketball Players During Practices and Games

Science.gov (United States)

Kuzuhara, Kenji; Shibata, Masashi; Uchida, Ryo

2016-01-01

Context: Mini-basketball is one of the most popular junior sports in Japan. Mini-basketball–related injuries may increase because of early specialization. However, no reports have been published to date concerning basketball injuries in children younger than 12 years of age. Objective: To prospectively study the incidence, sites, types, and mechanisms of injuries in mini-basketball teams. Design: Descriptive epidemiology study. Setting: Mini-basketball teams in Kobe, Japan. Patients or Other Participants: A total of 95 players in 7 community-based mini-basketball club teams (age range, 9 through 12 years). Main Outcome Measure(s): Data on all practice and game injuries for the 2013–2014 season were collected using an injury report form. Injury rates were calculated according to site, type, and mechanism. Results: The overall injury rate was 3.83 per 1000 athlete-hours (AHs). The game injury rate (12.92/1000 AHs) was higher than the practice injury rate (3.13/1000 AHs; P basketball players. The high practice injury rate in this study may be due to specific factors related to growth, such as individual differences in height, or to skills, such as inexperience in ball handling. PMID:27922287

Communication aspects of a three-player Prisoner's Dilemma quantum game

International Nuclear Information System (INIS)

Ramzan, M; Khan, M K

2009-01-01

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

Utilization of cues in action anticipation in table tennis players.

Science.gov (United States)

Zhao, Qi; Lu, Yingzhi; Jaquess, Kyle J; Zhou, Chenglin

2018-04-11

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.

Dental Trauma and Mouthguard Usage among Soccer Players in Izmir, Turkey

Directory of Open Access Journals (Sweden)

Ilhan Uzel

2014-07-01

Full Text Available The aims of this study were to verify the occurrence of dental injuries in 343 amateur Turkish soccer players in İzmir and the level of knowledge of the teams’ soccer players about mouthguards. The soccer players were interviewed to determine the occurrence of dental trauma during soccer and mouthguard usage level. The data were analyzed with descriptive analysis to determine absolute and relative frequencies of answers for each one of the questions. Only 35 (10.2% soccer players reported the occurrence of some type of dental injury during soccer practice. Regarding emergency conducts, approximately 84 players (24.48% answered that replantation could be obtained after teeth avulsion, 23 players (27.38% answered that successful replantation could be obtained within 2 hours immediately after injury, and 60.71% were not able to answer this question. Regarding mouthguard use, 61.8% of soccer players did not know about mouthguards. It was possible to conclude that dental injuries are common during amateur soccer practice and that there is a lack of information in the soccer players related to the emergency conducts and prevention of dental trauma.

Effects of Plyometric and Directional Training on Speed and Jump Performance in Elite Youth Soccer Players.

Science.gov (United States)

Beato, Marco; Bianchi, Mattia; Coratella, Giuseppe; Merlini, Michele; Drust, Barry

2018-02-01

Beato, M, Bianchi, M, Coratella, G, Merlini, M, and Drust, B. Effects of plyometric and directional training on speed and jump performance in elite youth soccer players. J Strength Cond Res 32(2): 289-296, 2018-Soccer players perform approximately 1,350 activities (every 4-6 seconds), such as accelerations/decelerations and changes of direction (CODs) during matches. It is well established that COD and plyometric training have a positive impact on fitness parameters in football players. This study analyzed the effect of a complex COD and plyometric protocol (CODJ-G) compared with an isolated COD protocol (COD-G) training on elite football players. A randomized pre-post parallel group trial was used in this study. Twenty-one youth players were enrolled in this study (mean ± SD; age 17 ± 0.8 years, mass 70.1 ± 6.4 kg, and height 177.4 ± 6.2 cm). Players were randomized into 2 different groups: CODJ-G (n = 11) and COD-G (n = 10), training frequency of 2 times a week more than 6 weeks. Sprint 10, 30, and 40 m, long jump, triple hop jump, and 505 COD test were considered. Exercise-induced within-group changes in performance for both CODJ-G and COD-G: long jump (effect size [ES] = 0.32 and ES = 0.26, respectively) and sprint 10 m (ES = -0.51 and ES = -0.22, respectively), after 6 weeks of training. Moreover, CODJ-G reported substantially better results (between-group changes) in long jump test (ES = 0.32). In conclusion, this study showed that short-term protocols (CODJ-G and COD-G) are important and able to give meaningful improvements on power and speed parameters in a specific soccer population. CODJ-G showed a larger effect in sprint and jump parameters compared with COD-G after the training protocol. This study offers important implications for designing COD and jumps training in elite soccer.

Does Game Participation Impact Cognition and Symptoms in Elite Football Players?

Science.gov (United States)

Mrazik, Martin; Naidu, Dhiren; Manning, David E; Brooks, Brian L

2016-09-01

To measure neurocognitive functioning in college and professional football players after game participation. Retrospective, cross-sectional cohort design. Ninety-four male university and professional football players. All participants completed Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) testing at baseline, and either at postconcussion (group 1) or postgame (group 2) participation. Results from the 5 ImPACT composite scores (Verbal Memory, Visual Memory, Visual Motor Speed, Reaction Time and Impulse Control) and Total Symptom Score. Repeated-measures analysis of variance demonstrated a significant main effect for time (improvements) in 3 of 5 domains for the postconcussion group, but no improvements in the postgame group. The postconcussion group presented with significantly improved results on 4 of 5 ImPACT domains compared with the postgame group at the follow-up time interval. Participation in a football game with potential cumulative head contacts did not yield increased symptoms or cognitive impairment. However, the absence of improvement in cognitive functioning in noninjured football players, which was found in those players who were returned to play after an injury, may suggest that there is a measureable impact as a result of playing football.

Shuttle-Run Sprint Training in Hypoxia for Youth Elite Soccer Players: A Pilot Study

Directory of Open Access Journals (Sweden)

Hannes Gatterer

2014-12-01

Full Text Available The purposes of the present study were to investigate if a shuttle-run sprint training performed in a normobaric hypoxia chamber of limited size (4.75x2.25m is feasible, in terms of producing the same absolute training load, when compared to training in normoxia, and b if such training improves the repeated sprint ability (RSA and the Yo-Yo intermittent recovery (YYIR test outcome in young elite soccer players. Players of an elite soccer training Centre (age: 15.3 ± 0.5 years, height: 1.73 ± 0.07 m, body mass: 62.6 ± 6.6 kg were randomly assigned to a hypoxia or a normoxia training group. Within a 5-week period, players, who were not informed about the hypoxia intervention, performed at least 7 sessions of identical shuttle-run sprint training either in a normal training room (FiO2 = 20.95% or in a hypoxic chamber (FiO2 = 14.8%; approximately 3300m, both equipped with the same floor. Each training session comprised 3 series of 5x10s back and forth sprints (4.5m performed at maximal intensity. Recovery time between repetitions was 20s and between series 5min. Before and after the training period the RSA (6 x 40m shuttle sprint with 20 s rest between shuttles and the YYIR test were performed. The size of the chamber did not restrict the training intensity of the sprint training (both groups performed approximately 8 shuttles during 10s. Training in hypoxia resulted in a lower fatigue slope which indicates better running speed maintenance during the RSA test (p = 0.024. YYIR performance increased over time (p = 0.045 without differences between groups (p > 0.05. This study showed that training intensity of the shuttle-run sprint training was not restricted in a hypoxic chamber of limited size which indicates that such training is feasible. Furthermore, hypoxia compared to normoxia training reduced the fatigue slope during the RSA test in youth soccer players.

Identification af explosive power factors as predictors of player quality in young female volleyball players.

Science.gov (United States)

Grgantov, Zoran; Milić, Mirjana; Katić, Ratko

2013-05-01

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.

Executive Functioning in Highly Talented Soccer Players

Science.gov (United States)

Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap

2014-01-01

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

Executive functioning in highly talented soccer players.

Directory of Open Access Journals (Sweden)

Lot Verburgh

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.

Design Strategies for Balancing Exertion Games

DEFF Research Database (Denmark)

Jensen, Mads Møller; Grønbæk, Kaj

2016-01-01

In sports, if players' physical and technical abilities are mismatched, the competition is often uninteresting for them. With the emergence of exertion games, this could be changing. Player balancing, known from video games, allows players with different skill levels to compete, however, it is un......In sports, if players' physical and technical abilities are mismatched, the competition is often uninteresting for them. With the emergence of exertion games, this could be changing. Player balancing, known from video games, allows players with different skill levels to compete, however......, it is unclear how balancing mechanisms should be applied in exertion games, where physical and digital elements are fused. In this paper, we present an exertion game and three approaches for balancing it; a physical, an explicit-digital and an implicit-digital balancing approach. A user study that compares...... these three approaches is used to investigate the qualities and challenges within each approach and explore how the player experience is affected by them. Based on these findings, we suggest four design strategies for balancing exertion games, so that players will stay engaged in the game and contain...

Knee Control and Jump-Landing Technique in Young Basketball and Floorball Players.

Science.gov (United States)

Leppänen, M; Pasanen, K; Kulmala, J-P; Kujala, U M; Krosshaug, T; Kannus, P; Perttunen, J; Vasankari, T; Parkkari, J

2016-04-01

Poor knee alignment is associated with increased loading of the joints, ligaments and tendons, and may increase the risk of injury. The study purpose was to compare differences in knee kinematics between basketball and floorball players during a vertical drop jump (VDJ) task. We wanted to investigate whether basketball players, whose sport includes frequent jump-landings, exhibited better knee control compared with floorball players, whose sport involves less jumping. Complete data was obtained from 173 basketball and 141 floorball players. Peak knee valgus and flexion angles during the VDJ were analyzed by 3D motion analysis.Larger knee valgus angles were observed among basketball players (- 3.2°, 95%CI -4.5 to - 2.0) compared with floorball players (- 0.9°, 95%CI -2.3 to 0.6) (P=0.022). Basketball players landed with a decreased peak knee flexion angle (83.1°, 95%CI 81.4 to 84.8) compared with floorball players (86.5°, 95%CI 84.6 to 88.4) (P=0.016). There were no significant differences in height, weight or BMI between basketball and floorball players. Female athletes exhibited significantly greater valgus angles than males. This study revealed that proper knee control during jump-landing does not seem to develop in young athletes simply by playing the sport, despite the fact that jump-landings occur frequently in practice and games. © Georg Thieme Verlag KG Stuttgart · New York.

Shoulder pain among high-level volleyball players and preseason features.

Science.gov (United States)

Forthomme, Benedicte; Wieczorek, Valerie; Frisch, Anne; Crielaard, Jean-Michel; Croisier, Jean-Louis

2013-10-01

The main goal of this prospective study was to identify the most significant intrinsic risk factors for shoulder pain by measuring strength developed by shoulder rotators and by carrying out various morphostatic assessments. Sixty-six players (mean ± SD age = 24 ± 5 yr) were recruited from nine volleyball teams from the first and second divisions (34 men and 32 women) to participate in the study. Before the start of the volleyball season, all the participants completed a preseason questionnaire and underwent both a bilateral isokinetic evaluation of the shoulders and morphostatic measurements. During the subsequent 6 months of the competition period, the players reported through a weekly questionnaire any shoulder pain experienced. During the ongoing season, 23% (15 of 66 players) of the volleyball players experienced dominant shoulder pain. Interestingly, participants who reported a history of dominant shoulder pain were found to have nine times higher risk of suffering further pain in their dominant shoulder. The eccentric maximal strength developed by the internal and external rotators was found to represent a protective factor in the volleyball players (respective odds ratios = 0.946, P = 0.01 and 0.94, P = 0.05). No risk factors were found among the shoulder morphostatic measurements. In our study, the evaluation of shoulder rotator muscle strength through isokinetic assessment, especially eccentric mode, appeared to be the most contributing parameter to identify risk factors for shoulder pain. This evaluation should allow to better identify players at risk.

Thirty Percent of Female Footballers Terminate Their Careers Due to Injury - A Retrospective Study Among Former Polish Players.

Science.gov (United States)

Grygorowicz, Monika; Michałowska, Martyna; Jurga, Paulina; Piontek, Tomasz; Jakubowska, Honorata; Kotwicki, Tomasz

2017-09-27

Female football is becoming an increasingly popular women's team sports discipline around the world. The Women's Football Committee in Polish Football Association (WFC_PFA) has developed a long-term strategic plan to popularize the discipline across the country and enhance girls' participation. On one hand, it is postulated to increase the number of female footballers, and on the other hand it is crucial to decrease the number of girls quitting football prematurely. To find the reasons for sports career termination among female football players. cross-sectional with retrospective information about reasons of career termination. On-line questionnaire was filled out by on-line access. Ninety-three former female footballers. factors leading to career termination. Participants completed the on-line questionnaire. The analysis was performed referring to two groups: "injury group" - in which the injury was the main reason for quitting football, and "other group" - in which the female player stopped playing football due to all other factors. Thirty percent of former Polish female football players terminated their career due to a long-term treatment for an injury. Over 27 percent (27.7%) females had ended their careers because they were not able to reconcile sports with work/studying. Over 10 percent (10.8%) of former football players reported that becoming a wife and/or mother was the reason for career termination. Losing motivation and interest in sport was reported by 9.2%(n=6) of present study participants who decided to terminate the career due to non-injury reasons. The results clearly show that more effort is needed to support female football players, especially after an injury, so that they do not quit the sport voluntarily.

A prospective study of concussions among National Hockey League players during regular season games: the NHL-NHLPA Concussion Program.

Science.gov (United States)

Benson, Brian W; Meeuwisse, Willem H; Rizos, John; Kang, Jian; Burke, Charles J

2011-05-17

In 1997, the National Hockey League (NHL) and NHL Players' Association (NHLPA) launched a concussion program to improve the understanding of this injury. We explored initial postconcussion signs, symptoms, physical examination findings and time loss (i.e., time between the injury and medical clearance by the physician to return to competitive play), experienced by male professional ice-hockey players, and assessed the utility of initial postconcussion clinical manifestations in predicting time loss among hockey players. We conducted a prospective case series of concussions over seven NHL regular seasons (1997-2004) using an inclusive cohort of players. The primary outcome was concussion and the secondary outcome was time loss. NHL team physicians documented post-concussion clinical manifestations and recorded the date when a player was medically cleared to return to play. Team physicians reported 559 concussions during regular season games. The estimated incidence was 1.8 concussions per 1000 player-hours. The most common postconcussion symptom was headache (71%). On average, time loss (in days) increased 2.25 times (95% confidence interval [CI] 1.41-3.62) for every subsequent (i.e., recurrent) concussion sustained during the study period. Controlling for age and position, significant predictors of time loss were postconcussion headache (p < 0.001), low energy or fatigue (p = 0.01), amnesia (p = 0.02) and abnormal neurologic examination (p = 0.01). Using a previously suggested time loss cut-point of 10 days, headache (odds ratio [OR] 2.17, 95% CI 1.33-3.54) and low energy or fatigue (OR 1.72, 95% CI 1.04-2.85) were significant predictors of time loss of more than 10 days. Postconcussion headache, low energy or fatigue, amnesia and abnormal neurologic examination were significant predictors of time loss among professional hockey players.

Cross-sectional and longitudinal examination of exercise capacity in elite youth badminton players

DEFF Research Database (Denmark)

Madsen, Christian Møller; Badault, Benjamin; Nybo, Lars

2018-01-01

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...

Inadequate pre-season preparation of schoolboy rugby players - a ...

African Journals Online (AJOL)

... 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.

Psychopathology of Online Poker Players: Review of Literature.

Science.gov (United States)

Moreau, Axelle; Chabrol, Henri; Chauchard, Emeline

2016-06-01

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.

Nutrient intake and blood iron status of male collegiate soccer players.

Science.gov (United States)

Noda, Yuka; Iide, Kazuhide; Masuda, Reika; Kishida, Reina; Nagata, Atsumi; Hirakawa, Fumiko; Yoshimura, Yoshitaka; Imamura, Hiroyuki

2009-01-01

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.

What is the Safest Sprint Starting Position for American Football Players?

Directory of Open Access Journals (Sweden)

Bruno Bonnechere, Benoit Beyer, Marcel Rooze, Jan Serge Van Sint

2014-06-01

Full Text Available The main objective of this study was to perform a biomechanical analysis of three different sprint start patterns to determine the safest position in term of neck injury and Sport-Related Concussion (SRC. The second objective was to collect data on the learning process effect between football players and non-players. Three different sprint initial positions adopted by football players were studied (i.e., 4-, 3- and 2-point positions. Twenty five young healthy males, including 12 football players, participated to this study. A stereophotogrammetric system (i.e., Vicon was used to record motion patterns and body segments positions. Various measurements related to head and trunk orientation, and player field-of-view were obtained (e.g., head height, trunk bending, time to reach upright position, head speed (vertical direction and body speed (horizontal direction. Learning process was found to have no influence on studied parameters. Head redress is also delayed when adopting a 4-point position leading to a reduce field-of-view during the start and increasing therefore the probability of collision. Concerning the three different positions, the 4-point position seems to be the more dangerous because leading to higher kinetic energy than the 2- and 3-point start positions. This study proposes a first biomechanical approach to understand risk/benefit balance for athletes for those three different start positions. Results suggested that the 4-point position is the most risky for football players.

Pre-training perceived wellness impacts training output in Australian football players.

Science.gov (United States)

Gallo, Tania F; Cormack, Stuart J; Gabbett, Tim J; Lorenzen, Christian H

2016-08-01

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.

Physiological characteristics of elite and sub-elite badminton players.

Science.gov (United States)

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

2009-12-01

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.

Core executive functions are associated with success in young elite soccer players.

Directory of Open Access Journals (Sweden)

Torbjörn Vestberg

Full Text Available Physical capacity and coordination cannot alone predict success in team sports such as soccer. Instead, more focus has been directed towards the importance of cognitive abilities, and it has been suggested that executive functions (EF are fundamentally important for success in soccer. However, executive functions are going through a steep development from adolescence to adulthood. Moreover, more complex EF involving manipulation of information (higher level EF develop later than simple executive functions such as those linked to simple working memory capacity (Core EF. The link between EF and success in young soccer players is therefore not obvious. In the present study we investigated whether EF are associated with success in soccer in young elite soccer players. We performed tests measuring core EF (a demanding working memory task involving a variable n-back task; dWM and higher level EF (Design Fluency test; DF. Color-Word Interference Test and Trail Making Test were performed on an exploratory level as they contain a linguistic element. The lower level EF test (dWM was taken from CogStateSport computerized concussion testing and the higher level EF test (DF was from Delis-Kaplan Executive Function System test battery (D-KEFS. In a group of young elite soccer players (n = 30; aged 12-19 years we show that they perform better than the norm in both the dWM (+0.49 SD and DF (+0.86 SD. Moreover, we could show that both dWM and DF correlate with the number of goals the players perform during the season. The effect was more prominent for dWM (r = 0.437 than for DF (r = 0.349, but strongest for a combined measurement (r = 0.550. The effect was still present when we controlled for intelligence, length and age in a partial correlation analysis. Thus, our study suggests that both core and higher level EF may predict success in soccer also in young players.

Nutritional Practices of National Female Soccer Players: Analysis and Recommendations

Science.gov (United States)

Martin, Louise; Lambeth, Anneliese; Scott, Dawn

2006-01-01

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

Nutritional practices of national female soccer players: analysis and recommendations.

Science.gov (United States)

Martin, Louise; Lambeth, Anneliese; Scott, Dawn

2006-01-01

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.

Evaluating Telepresence Experience and Game Players' Intention to Purchase Product Advertised in Advergame

OpenAIRE

Zuhal Hussein; Nabsiah Abdul Wahid; Norizan Saad

2010-01-01

In line with changes of consumers modern lifestyle has call for the advertising strategy to change. This research is to find out how game with telepresence and product experience embedded in the computer game to affect users- intention to purchase. Game content developers are urging to consider of placing product message as part of game design strategy that can influence the game player-s intention to purchase. Experiment was carried out on two hundred and fifty undergraduate students who vol...

Comparison of posture among adolescent male volleyball players and non-athletes

Directory of Open Access Journals (Sweden)

Małgorzata Grabara

2014-11-01

Full Text Available Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified.

Comparison of posture among adolescent male volleyball players and non-athlete

Directory of Open Access Journals (Sweden)

Małgorzata Grabara

2014-10-01

Full Text Available Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified.

Comparison of posture among adolescent male volleyball players and non-athletes

Science.gov (United States)

2014-01-01

Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified. PMID:25729154

In-season training periodization of professional soccer players

Directory of Open Access Journals (Sweden)

A Los Arcos

2017-04-01

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.

Soccer Injuries in Players Aged 7 to 12 Years: A Descriptive Epidemiological Study Over 2 Seasons.

Science.gov (United States)

Rössler, Roland; Junge, Astrid; Chomiak, Jiri; Dvorak, Jiri; Faude, Oliver

2016-02-01

As part of a risk-management approach, sound epidemiological data are needed to develop prevention programs. A recent review on soccer injuries of players younger than 19 years concluded that prospective data concerning children are lacking. To analyze the incidence and characteristics of soccer injuries in children aged 7 to 12 years. Descriptive epidemiological study. The present survey was a prospective descriptive epidemiological study on soccer injuries over 2 seasons in the Czech Republic and Switzerland. Exposure of players during training and match play (in hours) and injury data were reported by coaches via an Internet-based registration system. Location, type, and severity of injuries were classified according to an established consensus. Injury characteristics are presented as absolute numbers and injury incidence rates (injuries per 1000 hours of soccer exposure). An injury was defined as any physical complaint sustained during a scheduled training session or match play resulting in at least 1 of the following: (1) inability to complete the current match or training session, (2) absence from subsequent training sessions or matches, and (3) injury requiring medical attention. In total, 6038 player-seasons with 395,295 hours of soccer exposure were recorded. The mean (±SD) age of the players was 9.5 ± 2.0 years, and 3.9% of the participants were girls. A total of 417 injuries were reported. Most (76.3%) injuries were located in the lower limbs, with 15.6% located in the upper limbs. Joint and ligament injuries comprised 30.5%, contusions 22.5%, muscle and tendon injuries 18.5%, and fractures and bone injuries 15.4% of all injuries; 23.7% of injuries led to more than 28 days of absence from sport participation. The overall injury incidence was 0.61 (95% CI, 0.53-0.69) injuries per 1000 hours of soccer exposure during training sessions and 4.57 (95% CI, 4.00-5.23) during match play. Injury incidence rates increased with increasing age. The observed injury

Relationship between goal orientation and perceived motivational climate in football players of different playing positions

Directory of Open Access Journals (Sweden)

Özkan ÇEKİÇ

2017-09-01

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.

Analyzing three-player quantum games in an EPR type setup.

Directory of Open Access Journals (Sweden)

James M Chappell

Full Text Available We use the formalism of Clifford Geometric Algebra (GA to develop an analysis of quantum versions of three-player non-cooperative games. The quantum games we explore are played in an Einstein-Podolsky-Rosen (EPR type setting. In this setting, the players' strategy sets remain identical to the ones in the mixed-strategy version of the classical game that is obtained as a proper subset of the corresponding quantum game. Using GA we investigate the outcome of a realization of the game by players sharing GHZ state, W state, and a mixture of GHZ and W states. As a specific example, we study the game of three-player Prisoners' Dilemma.

A PHYSIOLOGICAL CASE STUDY OF A PARALYMPIC WHEELCHAIR TENNIS PLAYER: REFLECTIVE PRACTISE

Directory of Open Access Journals (Sweden)

Nicholas J. Diaper

2009-06-01

Full Text Available This study was designed to examine the physiological changes caused by long-term training in a world class female tennis player in preparation for a major championship. Additionally, we aim to describe the training interventions and determine a suitable cooling strategy that was to be used at the 2004 Paralympic Games. The athlete underwent regular physiological assessment during 2003-2004. Physiological measures involved body composition, submaximal and peak oxygen uptake and key variables associated with maximal sprinting. In addition, a suitable match-play cooling intervention and hydration strategy was also explored. Body composition improved over the course of the study. Aerobic capacity fell by 21%, yet the submaximal physiological variables such as lactate profile and pushing economy improved. The trade off of aerobic capacity was perhaps noticeably counter-balanced with the maintenance of the peak sprinting speed and improvement found in the fatigue profile across ten repeated sprints. The extensive training programme was responsible for these changes and these adaptations resulted in a more confident athlete, in peak physical condition leading into the Paralympic Games. It is difficult to appreciate the extent to which this work had an impact on tennis performance given the skill requirements of wheelchair tennis and this warrants future attention

Physical performance and positional differences among young female volleyball players.

Science.gov (United States)

Paz, Gabriel A; Gabbett, Tim J; Maia, Marianna F; Santana, Haroldo; Miranda, Humberto; Lima, Vicente

2017-10-01

The purpose of this study was to investigate the association among anthropometric, physical performance parameters, and dynamic postural control attributes of young female volleyball athletes, and to determine if differences exist in these attributes according to playing position. Forty-three young female volleyball players participated in this study. Players were divided by position into hitters (N.=17), middle blockers (N.=8), setters (N.=10), and liberos (N.=8). Stature, body mass, vertical jump (VJ), peak power, horizontal jump (HJ), sit-and-reach (SRT), star excursion balance (SEBT), and agility (e.g. shuttle run and Illinois agility test) tests were assessed on non-consecutive days in randomized order. No difference was found between groups for SRT, peak power, VJ, and HJ (P≤0.05). Middle blockers and hitters were taller than setters (P≤0.05). Middle blockers were also taller than liberos (P=0.017). Significant differences were observed among groups for agility tests, with hitters significantly faster than setters (P=0.023) and middle blockers (P=0.037). In addition, liberos were significantly faster than setters (P=0.032) and middle blockers (P=0.046), during the Illinois agility test. No difference was observed between groups for reach distance scores in the SEBT. These results demonstrate important positional differences in agility measures of young female volleyball players. Coaches can use this information to determine the type of physical profile that is needed for specific positions and to design training programs to maximize strength, power, and neuromuscular development of young female volleyball athletes.

Heart Rate Variability Discriminates Competitive Levels in Professional Soccer Players.

Science.gov (United States)

Proietti, Riccardo; di Fronso, Selenia; Pereira, Lucas A; Bortoli, Laura; Robazza, Claudio; Nakamura, Fabio Y; Bertollo, Maurizio

2017-06-01

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.

Gamification in Fostering Creativity: Player Type Approach

Directory of Open Access Journals (Sweden)

Marius Kalinauskas

2015-02-01

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

Design of a Virtual Player for Joint Improvisation with Humans in the Mirror Game.

Science.gov (United States)

Zhai, Chao; Alderisio, Francesco; Słowiński, Piotr; Tsaneva-Atanasova, Krasimira; di Bernardo, Mario

2016-01-01

Joint improvisation is often observed among humans performing joint action tasks. Exploring the underlying cognitive and neural mechanisms behind the emergence of joint improvisation is an open research challenge. This paper investigates jointly improvised movements between two participants in the mirror game, a paradigmatic joint task example. First, experiments involving movement coordination of different dyads of human players are performed in order to build a human benchmark. No designation of leader and follower is given beforehand. We find that joint improvisation is characterized by the lack of a leader and high levels of movement synchronization. Then, a theoretical model is proposed to capture some features of their interaction, and a set of experiments is carried out to test and validate the model ability to reproduce the experimental observations. Furthermore, the model is used to drive a computer avatar able to successfully improvise joint motion with a human participant in real time. Finally, a convergence analysis of the proposed model is carried out to confirm its ability to reproduce joint movements between the participants.

COMPARISON OF SOME MOTOR ABILITIES OF MALE BASKETBALL AND HANDBALL PLAYERS

OpenAIRE

Hürmüz KOÇ; Atilla PULUR; Ebru Olcay KARABULUT

2011-01-01

In this study, some motoric characteristics of basketball and handball players with similar physical characteristics were compared. 24 handball players at the age of 12.5 ± 0.6 (mean ± sd) years old and 18 basketball players at the age of 12.8 ± 0.8 (mean ± sd) years old, all of whom have trained regularly for at least 3 years, participated in the study. Parameters such as, age, height, body weight, body fat percentage, flexibility, upper extremity velocity (arm movement velocity), equilibriu...

Perceived motivational factors for female football players during rehabilitation after sports injury - a qualitative interview study.

Science.gov (United States)

Hildingsson, Malin; Fitzgerald, Ulrika Tranaeus; Alricsson, Marie

2018-04-01

Compliance with a rehabilitation program is significant among athletes following a sports injury. It is also one of the main factors that influence the rehabilitation process; moreover, the outcome is also influenced by the athlete's motivation. It is primarily an autonomous motivation, resulting in rehabilitation adherence. The aim of this study was to investigate the perceived motivation of female football players during rehabilitation after a sports injury and the extent to which these motivating factors were autonomous. Qualitative interviews, based on a semistructured interview guide with injured female football players undergoing rehabilitation, were analyzed using content analysis. The motivational factors that were described were their set goals, social support as well as external and internal pressures during rehabilitation. The perceived autonomy varied somewhat but overall, they experienced external motivation; therefore, the behavior was not entirely self-determined. Results are expected to provide a better understanding of women football players' motivation in relation to their rehabilitation; hence, physiotherapists and coaches who are part of the rehabilitation process can contribute by increasing the autonomous motivation, thus, improving the compliance and outcome of the rehabilitation.

Body composition of italian female hockey players

Directory of Open Access Journals (Sweden)

P Pavan

2009-07-01

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.

The health status of retired American football players: Super Bowl III revisited.

Science.gov (United States)

Nicholas, Stephen J; Nicholas, James A; Nicholas, Calvin; Diecchio, Jennifer R; McHugh, Malachy P

2007-10-01

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.

The Relative Age Effect and Physical Fitness Characteristics in German Male Tennis Players

Directory of Open Access Journals (Sweden)

Alexander Ulbricht, Jaime Fernandez-Fernandez, Alberto Mendez-Villanueva, Alexander Ferrauti

2015-09-01

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.

Early Sport Specialization: Effectiveness and Risk of Injury in Professional Baseball Players.

Science.gov (United States)

Wilhelm, Andrew; Choi, Changryol; Deitch, John

2017-09-01

The rate of early sport specialization in professional baseball players is unknown. To report the incidence and age of sport specialization in current professional baseball players and the impact of early specialization on the frequency of serious injuries sustained during the players' careers. We also queried participants about when serious injuries occurred, the players' current position on the field, and their opinions regarding the need for young athletes to specialize early to play at the professional level. Descriptive epidemiological study. A total of 102 current professional baseball players anonymously completed a 7-question written survey. Early sport specialization was defined as "single-sport participation prior to high school." Injury was defined as "a serious injury or surgery that required the player to refrain from sports (baseball) for an entire year." Chi-square tests were used to investigate the risk of injury in those who specialized early in baseball versus those who did not. Independent-sample t tests were used to compare injury rates based on current player position. Fifty (48%) baseball players specialized early. The mean age at initiation of sport specialization was 8.91 years (SD, 3.7 years). Those who specialized early reported more serious injuries (mean, 0.54; SD, 0.838) during their professional baseball career than those who did not (mean, 0.23; SD, 0.425) ( P = .044). Finally, 63.4% of the queried players believed that early sport specialization was not required to play professional baseball. Our study demonstrated a statistically significant higher rate of serious injury during a baseball player's professional career in those players who specialized early. Most current professional baseball players surveyed believed that sport specialization was not required prior to high school to master the skills needed to play at the professional level. Our findings demonstrate an increased incidence of serious injuries in professional baseball

Physical qualities and activity profiles of sub-elite and recreational Australian football players.

Science.gov (United States)

Stein, Josh G; Gabbett, Tim J; Townshend, Andrew D; Dawson, Brian T

2015-11-01

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.

Heart Rate Monitor for Portable MP3 Player.

Science.gov (United States)

Kim, Jaywoo; Lee, Mi-Hee; Lee, Hyoung-Ki; Choi, Kiwan; Bang, Seokwon; Kim, Sangryong

2005-01-01

This paper presents a photoplethysmography sensor based on a heart rate monitor for a portable MP3 player. Two major design issues are addressed: one is to acquire the sensor signal with a proper amplitude despite a wide range of variation and the other is to handle the noise contaminated signal which is caused by a motion artifact. A benchmarking test with a professional medical photoplethysmography sensor shows that our device performs very well in calculating heart rate even though our photoplethysmography sensor module was designed to be cost effective.

Analysis of Bridge Player Profiles According to Their Intelligence Areas

Science.gov (United States)

Bilir, Fatma Pervin; Sirin, Yeliz

2017-01-01

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…

Comparative study of anthropometric variables in female classical ballet dancers, volleyball players and physically active subjects

Directory of Open Access Journals (Sweden)

Marco Aurélio Vaz

2009-01-01

Full Text Available The objective of this study was to compare anthropometric variables (body weight, height, and percent body fat and plantarflexion and dorsiflexion range of motion (ROM between three different groups of women: classical ballet dancers (n=14, volleyball players (n=22 and physically active subjects (n=13. The assumption was that different functional requirements should produce differences in the anthropometric variables and ROM between the three groups. Body weight and height were higher in volleyball players (66.42 ± 5.8 kg; 174.77 ± 5.6 cm, followed by physically active women (59.93 ±10.3 kg; 164 ± 7.5 cm and ballet dancers (49.25 ± 4.5 kg; 157.03 ± 3.6 cm (p<0.05. Percent body fat was higher in physically active women (30.67 ± 4.6% compared to theother two groups, which showed similar percentages (volleyball players: 24.93 ± 4.1%; ballet dancers: 21.94 ± 4.3%. The three groups were similar in terms of total ankle ROM and active dorsiflexion ROM between the right and left sides. However, plantarflexion ROM was higher in ballet dancers (~83°, followed by physically active women (~68° and volleyball players who presented the smallest ROM (~60°. The different requirements imposed by the three distinct physical activities seem to be responsible for changes in some of the anthropometric variables and ankle joint ROM.

There is no game without a player

DEFF Research Database (Denmark)

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...

Sling-based Exercise for External Rotator Muscles: Effects on Shoulder Profile in Young Recreational Tennis Players

Science.gov (United States)

Goulet, Charles; Rogowski, Isabelle

2016-12-19

Context: Tennis playing generates specific adaptations, particularly at the dominant shoulder. It remains to be established whether shoulder strength balance can be restored by sling-based training for adolescent recreational tennis players. Objective: We added a sling-based exercise for shoulder external rotators to investigate its effects on external rotator muscle strength, on internal rotator muscle strength, on glenohumeral range of motion and on tennis serve performance. Design: Test-retest design. Setting: Tennis training sports facilities. Participants: Twelve adolescent male players volunteered to participate in this study (age: 13.3 ± 0.5 years; height: 1.64 ± 0.07 cm, mass: 51.7 ± 5.8 kg, International Tennis Number: 8). Intervention: The procedure spanned 10 weeks. For the first five weeks, players performed their regular training (RT) twice a week. For the last five weeks, a sling-based exercise (SE) for strengthening the shoulder external rotator muscles was added to their regular training. Main Outcome Measures: Maximal isometric strength of shoulder external and internal rotator muscles and glenohumeral range of motion in external and internal rotation were assessed in both shoulders. Serve performance was also evaluated by accuracy and post-impact ball velocity, using a radar gun. Results: No change was found in any measurement after the RT period. Significant increases in external (~+5%; pexternal/internal strength ratio (~+4%; pexternal rotator muscles appears effective in restoring strength balance at the dominant shoulder, and may prevent adolescent tennis players from sustaining degenerative shoulder problems which could later impair their performance of daily and work-related tasks.

The role of community in the development of elite handball and football players in Denmark.

Science.gov (United States)

Rossing, N N; Nielsen, A B; Elbe, A-M; Karbing, D S

2016-01-01

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.

Plasma and erythrocyte phospholipid fatty acid profile in professional basketball and football players.

Science.gov (United States)

Tepsic, Jasna; Vucic, Vesna; Arsic, Aleksandra; Blazencic-Mladenovic, Vera; Mazic, Sanja; Glibetic, Marija

2009-10-01

The effect of intensive long-term physical activity on phospholipid fatty acid (FA) composition has not been studied thoroughly. We determined plasma and erythrocyte phospholipid FA status of professional basketball and football players. Our results showed differences in plasma FA profile not only between sportsmen and sedentary subjects, but also between two groups of sportsmen. Plasma FA profile in basketball players showed significantly higher proportion of n-6 FA (20:3, 20:4, and 22:4) and total polyunsaturated FA (PUFA) than controls, while football players had higher palmitoleic acid (16:1) than basketball players and controls. Total PUFA and 22:4 were also higher in basketball than in football players. Erythrocyte FA profile showed no differences between football players and controls. However, basketball players had higher proportion of 18:0 than controls, higher saturated FA and lower 18:2 than two other groups, and higher 22:4 than football players. These findings suggest that long-term intensive exercise and type of sport influence FA profile.

Study on the Application of TOPSIS Method to the Introduction of Foreign Players in CBA Games

Science.gov (United States)

Zhongyou, Xing

The TOPSIS method is a multiple attribute decision-making method. This paper introduces the current situation of the introduction of foreign players in CBA games, presents the principles and calculation steps of TOPSIS method in detail, and applies it to the quantitative evaluation of the comprehensively competitive ability during the introduction of foreign players. Through the analysis of practical application, we found that the TOPSIS method has relatively high rationality and applicability when it is used to evaluate the comprehensively competitive ability during the introduction of foreign players.

N-player quantum games in an EPR setting.

Directory of Open Access Journals (Sweden)

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.

Player Modeling for Intelligent Difficulty Adjustment

Science.gov (United States)