Effect of Rule Modifications on Kinematic Parameters Using Maturity Stage as a Moderating Variable in U-10 Football Players.

The aim of the present study was to analyse the effects of regulatory modifications in competitive situations on cinematic variables, considering maturity stage as a moderating factor, in youth football players. A quasi-experimental study was conducted in which 45 players with a mean age of 9.47 ± 0.54 participated. The independent variable analysed was the modification of rules (playing time, scoring, and specific rules). The dependent variables analysed were cinematic variables. These variables were recorded with WimuTM. The maturity stage was considered a moderating factor in this effect. The main results indicate that the modified competition reduced the total distance covered, maximum acceleration speed, and distance covered in acceleration and deceleration in different speed zones. In addition, the maturity stage was found to moderate the effect of the intervention on the total distance covered, distance covered by accelerating in zone 3, and distance covered by decelerating in zone 3. Thus, the proposed modification appeared to reduce the physical demand for competition. Furthermore, it reduced the differences between players with early maturational development and those with late maturational development.

Reliability of a Qualitative Instrument to Assess High-Risk Mechanisms during a 90° Change of Direction in Female Football Players.

Sidestep cuts between 60° and 180° and one-leg landings have been identified as the main mechanisms of ACL injuries in several sports. This study sought to determine intra- and inter-rater reliability of a qualitative tool to assess high-risk movements in a 90° change of direction when the test is applied in a real framework of sport practice. Female footballers from two teams (n = 38) participated in this study and were asked to perform 90° cutting trials to each side, which were simultaneously filmed from a frontal and a sagittal view. A total of 61 cases were selected for 2D qualitative observational analysis by three raters. Poor reliability was found among each pair of raters as well as moderate reliability when the Cutting Movement Assessment Score (CMAS) was given by the same rater at different moments, but with too high a minimum detectable change. On the other hand, raters presented a significant, as well as moderate-to-good intra-rater reliability for most items of the CMAS tool. There was, however, non-significant reliability between observers in rating most check-points of the tool. For these reasons, more objective guidelines and clearer definitions for each criterion within the CMAS, as well as a longer, standardised training period for novel observers, would be highly recommended to improve the reliability of this tool in an applied context with female footballers.

Effect of the Modification of the Number of Players, the Size of the Goal, and the Size of the Field in Competition on the Play Actions in U-12 Male Football.

A player's sports development involves a long process. The modification of rules for youth players seeks to adapt the sport to the child and his/her development. The manipulation of rules affects the technical and tactical skills demonstrated by players and, therefore, their development. The objective of this study was to analyse the effect of a reduction in the number of players (from 8 per team to 5 per team), the size of the goal (from 6 × 2 m to 3 × 2 m) and the playing space (from 58 × 38 m to 38 × 20 m), on the technical and tactical actions in youth football players. A quasi-experimental A-B-A design was implemented to assess the effect of the rule changes. The players (n = 40) played three tournaments using two competition formats (official rules, modified rules, and official rules). The results show that the use of the modified rules generated a greater number and variability in the technical-tactical actions, a greater number of actions with teammates in the pass line, a greater continuity in the game, a greater number of attack and defence actions in areas close to the goal, and favours team play. The experimental format fits the players' individual progression better (U-12) as well as the players' and teams' collective development, and it will allow players to evolve from the individual development of previous stages.

Efficacy and manner of execution of the serve in top-level womens beach volleyball players / Eficácia e maneira de execução do serviço em jogadoras de voleibol de praia de alto nível

ABSTRACT The study of the manner of execution (technique, and spatial aspects) can provide useful information to understand the game dynamics in beach volleyball and to obtain references values for the analysis of the game and the establishment of training goals. The aim of the study was to determine the influence of the manner of execution on serve and rally performance in elite women's beach volleyball players. A total of 3,009 serves from 44 women's players were analyzed. The variables studied were: serve technique, serve zone, serve destination, serve performance, and rally performance. An observational punctual, nomothetic, multidimensional, and intragroup design was used. A descriptive and inferential analysis of the data (Chi-Square Test) was done using SPSS v.21.0 software. The level of significance was set at p < .05. The manner of execution influences the serve performance. The jump float serve was the most used. The most effective destination was the zone between players, probability due to the players' displacement and interference between them. An absence of association between serve technique and rally performance was found. These findings showed possible connections between the way of executing the serve with the following actions done by the players and the players' strategies to control their physical load. These values may be useful to guide to players training, or to evaluate players in competition.

RESUMO O estudo da forma de execução (técnica e aspectos espaciais) pode fornecer informações úteis para compreender a dinâmica do jogo no vôlei de praia e obter valores de referência para a análise do jogo e o estabelecimento de metas de treinamento. O objetivo do estudo foi determinar a influência da forma de execução no desempenho de saque e rali em jogadores de vôlei de praia de alto nível. Um total de 3.009 saques de 44 jogadoras de alto nível foram analisados. As variáveis ​​estudadas foram: técnica de saque, zona de saque, destino do saque, desempenho de saque e desempenho de rali. Um desenho observacional pontual, nomotético, multidimensional e intragrupo foi utilizado. Foi realizada uma análise descritiva e inferencial dos dados (Teste Qui-Quadrado) utilizando o software SPSS v.21.0. O nível de significância foi estabelecido em p <0,05. A maneira de execução influencia o desempenho do saque. O saque flutuante de salto foi o mais usado. O destino mais efetivo foi a zona entre jogadoras, provavelmente devido ao deslocamento das jogadoras e a interferência entre elas. Não foi encontrada associação entre a técnica de saque e o desempenho de rally. Esses achados mostraram possíveis associações entre a maneira de executar o saque com as ações seguintes realizadas pelas jogadoras e as estratégias das jogadoras para controlar sua carga física. Esses valores podem ser úteis para orientar o treinamento de jogadoras ou avaliar jogadoras em competição de vôlei de praia.

Design, Validation, and Reliability of an Observation Instrument for Technical and Tactical Actions of the Offense Phase in Soccer.

The use of observational methodology in the sports context provides coaches and other sports professionals with flexible tools that adapt to their needs. In collective sports, the use of these instruments is common for the technical and tactical analysis of the game. Based on the importance of data quality in these instruments, the purpose was to design, validate, and test the reliability of a mixed observational instrument of field formats and category systems to analyze technical and tactical actions in the offense phase in soccer. The instrument collects information regarding the actions with the ball, moment of the play (start, development, and end), and contextual situation for the offensive team and for the goalkeeper. The instrument design, validation, and reliability calculation were done in four stages: (a) review of the literature, (b) design the first draft of the instrument, (c) experts' qualitative and quantitative review of the instrument, and (d) observer training test (reliability calculation). The content validity was established by 12 experts (Ph.D. in sports science or soccer coach with at least of 10 years of coaching experience). The Delphi methodology was used. Experts did a quantitative (scale 0-10) and qualitative evaluation. Experts were asked about: (a) comprehension of the criteria, categorical cores, degree of openness, and their definitions, (b) pertinence of categorical cores and degree of openness, and (c) whether to include other categorical cores or degree of openness in the observation instrument. The lowest Aiken's V index was 0.91 for the categorical core "numerical situation with opponent goalkeeper." The inter- and intra-observer reliability presented good levels of agreement. The lowest Kappa index was 0.96 for the inter-reliability in the categorical core "defensive pressing lines" and was 0.98 for the intra-reliability in the categorical core "ball height (start of ball possession)," "distance of the defensive player," "ball height (end of ball possession)," "numerical situation," and "defensive pressing lines." The coefficients of the generalizability analysis showed a high level of accuracy, validity and reliability of the instrument. The results show that the instrument allows to obtain objective, valid and reliable information about the offensive phase in soccer.

Effect of educational training on nutrition and weight control in under-18 Spanish wrestlers

Abstract The aim of this study was to investigate the effect of a formative program concerning nutrition, weight control, and its risks wrestlers under the age of 18 (under-18) at the Spanish national level. The sample comprised 36 under-18 wrestlers that were pre-selected for the Spanish national team. A quasi-experimental design with a pre-test and post-test was used. The dependent variableswere the knowledge of nutrition and weight control and its risks. The independent variable was the educational program. The program had three 30-minute sessions that combined talks, videos, and tasks to complete. Descriptive and inferential analyses were done (t-test, Wilcoxon test). Results indicate that the educational program was effective at increasing under-18 wrestlers’ knowledge about weight control and its risks,but was ineffective with regard to nutrition knowledge. The paper concludes with a discussion regarding the effect of the intervention program, the difficulties with including this type of knowledge and skill in the preparation of combat sport athletes, and the need for further research in this area.(AU)

Diferencias en los indicadores de rendimiento técnico-tácticos entre ganadores y perdedores en la Women Rugby World Cup 2010 / Diferenças em indicadores técnicos e táticos de desempenho entre vencedores e perdedores na Copa do Mundo de 2010 / Differences in technical and tactical indicators of performance between winners and losers in the Women Rugby World Cup 2010

El objetivo del presente estudio fue conocer las diferencias en acciones técnico - tácticas entre equipos ganadores y perdedores en equipos de rugby femenino de alto rendimiento. Se analizaron 30 partidos disputados entre 12 equipos nacionales de la Women Rugby World Cup 2010. Las variables de estudio fueron las conductas relativas a la obtención del balón, el desarrollo del juego, a los reagrupamientos, los puntos marcados, y las faltas reglamentarias. Se realizó un análisis descriptivo e inferencial de los datos (prueba T de Student y análisis discriminate). Los equipos ganadores realizan más ensayos, transformaciones de ensayos, y pierden menos rucks y touches que los perdedores. Estos resultados pueden usarse como valores de referencia para el entrenamiento y el análisis del rendimiento en competición (AU)

O objetivo deste estudo foi determinar as diferenças nas ações técnicas - táticos entre ganhar e perder equipes em equipes de rugby das mulheres de alto desempenho. 30 partidas entre 12 equipes nacionais no Mulheres Rugby World Cup 2010. As variáveis do estudo foram analisados os comportamentos relacionados com a obtenção do desenvolvimento bola, jogo, o reagrupamento, os pontos marcados, e as falhas regulatórias. A análise descritiva dos dados e inferencial (teste t de Student e análise discriminante) foi realizada. As equipes vencedoras realizar mais testes, mudanças de teste, e perder menos rucks e toca os perdedores. Estes resultados podem ser usados como pontos de referência para treinamento e análise de desempenho na competição (AU)

The aim of this study was to determine the technical-tactical differences between winning and losing teams in high-level women’s rugby. Thirty matches between 12 national teams of the Women’s Rugby World Cup 2010 were analyzed. The studied variables were behaviors related to the scrum and lineouts, the game development, the rucks and mauls, the points, and the penalties. A descriptive and inferential analysis of the data was done (student t-test and discriminant analysis). Winning teams carried out more tries and try conversions, and they lose fewer rucks and lineouts than losing teams. These results can serve as reference values for training and for performance analysis of the competition (AU)

Design and validation of an observational instrument for technical and tactical actions in beach volleyball / Desenho e validação de um instrumento de observação para ações tático-técnicas em voleibol de praia / Diseño y validación de un instrumento de observación para las acciones técnico-tácticas en voley-playa

Technical and tactical actions determine performance in beach volleyball. This research develops and tests an instrument to monitor and evaluate the manner of execution and efficacy of the actions in beach volleyball. The purpose of this paper was to design and validate an observational instrument to analyze technical and tactical actions in beach volleyball. The instrument collects information regarding: a) information about the match (context), b) information about game situations, c) information about technical situations (serve, reception, set, attack, block, and court defense) in relation to player execution, role, manner of execution, execution zone, and efficacy, and d) information about the result of the play (win-lose and way point is obtained). Instrument design and validation was done in seven stages: a) review of literature and consultation of experts; b) pilot observation and data analysis; c) expert review of instrument (qualitative and quantitative evaluation); d) observer training test; e) expert review of instrument (content validity); f) measurement of the ability of the instrument to discriminate the result of the set; and g) measurement of the ability of the instrument to differentiate between competition age groups. The results show that the instrument allows for obtaining objective and valid information about the players and team from offensive and defensive technical and tactical actions, as well as indirectly from physical actions. The instrument can be used, in its entirety or partially, for researching and coaching purposes.

As ações tático-técnicas determinam o desempenho em voleibol de praia. Esta investigação desenvolveu e testou um instrumento para monitorar e avaliar a maneira de execução e eficácia das ações do jogo em voleibol de praia. O objetivo do presente estudo foi desenhar e validar um instrumento de observação para analisar as ações tático-técnicas em voleibol de praia. O instrumento coleta informações focando: a) informação sobre o jogo (contexto), b) informação sobre as situações do jogo, c) informação sobre as situações técnicas (serviço, recepção, distribuição, ataque, bloco, e defesa) em relação a execução do jogador, especialização, maneira de execução, zona de execução e eficácia, e d) informação sobre o resultado do jogo (ganhar-perder, e forma de obtenção dos pontos). O desenho e validação do instrumento foi realizado em sete fases: a) revisão da literatura e consulta dos experts; b) observação piloto e análise dos dados; c) revisão do instrumento pelo expert (avaliação qualitativa e quantitativa); d) treino-teste do observador; e) revisão do instrumento pelo expert (validade do conteúdo); f) medir a capacidade do instrumento para discriminar o resultado do set; e g) medir a capacidade do instrumento em relação a diferenças entre os grupos de idade na competição. Os resultados mostram que o instrumento permite a obtenção de informações objetivas e válidas sobre as ações tático-técnicas ofensivas e defensivas dos jogadores e das equipes, bem como (indiretamente) as ações físicas. O instrumento pode ser utilizado, totalmente ou parcialmente, para a investigação e treino.

Las acciones técnico-tácticas determinan el rendimiento en voley-playa. Este trabajo desarrolla y prueba un instrumento para monitorizar y evaluar la forma de ejecución y eficacia de las acciones en voley-playa. El propósito de este trabajo fue diseñar y validad un instrumento observacional para analizar las acciones técnico-tácticas en voley-playa. Este instrumento registra información relativa: a) información sobre el partido (contexto), b) información sobre la situación de juego, c) información sobre la situación en la que se realiza las acciones técnicas (saque, recepción, colocación, ataque, bloqueo, y defensa en campo) en relación al jugador que ejecuta, su función de juego, la forma de ejecución, la zona de ejecución, y la eficacia, y d) información sobre el resultado de la jugada (ganar-perder y forma como su obtuvo el punto). El diseño y validación del instrumento se realizó en siete etapas: a) revisión de la literatura y papel de expertos; b) Estudio piloto de observación y análisis de datos; c) revisión del instrumento por expertos (evaluación cualitativa y cuantitativa); d) Estudio piloto de entrenamiento de observadores; revisión del instrumento por expertos (validez de contenido); f) valoración de la capacidad de discriminación de diferencias entre ganadores y perdedores; y g) valoración de la capacidad de discriminación de diferencias entre grupos de edad. Los resultados muestran que el instrumento permite obtener información validad y objetiva sobre los jugadores y los equipos en sus acciones técnico-tácticas, como indirectamente las acciones físicas. Este instrumento puede ser usado en su totalidad o parcialmente para investigación y entrenamiento.

Physical and temporal characteristics of under 19, under 21 and senior male beach volleyball players.

This study aimed to assess the effects of age groups and players' role (blocker vs. defender specialist) in beach volleyball in relation to physical and temporal variables, considering quality of opposition. 1101 rallies from Under 19 (U19), 933 rallies from Under 21 (U21), and 1480 rallies from senior (senior) (Men's Swatch World Championships, 2010-2011) were observed using video match analysis. Cluster analysis was used to set teams' competitive levels and establish quality of opposition as "balanced", "moderate balanced" and "unbalanced" games. The analyzed variables were: temporal (duration of set, total rest time, total work time, duration of rallies, rest time between rallies) and physical (number of jumps and number of hits done by defenders and blockers) characteristics. A one-way ANOVA, independent samples t-test and multinomial logistic regression were performed to analyze the variables studied. The analysis of temporal and physical characteristics showed differences considering age group, player's role and quality of opposition. The duration of set, total rest time, and number of jumps done by defenders significantly increased from the U19 to senior category. Multinomial logistic regression showed that in: a) balanced games, rest time between rallies was higher in seniors than in U19 or U21; number of jumps done by defenders was higher in seniors than in U19) and U21; b) moderate balanced games, number of jumps done by defenders was higher in seniors than in U21 and number of jumps done by blockers was smaller in U19 than U21 or seniors; c) unbalanced games, no significant findings were shown. This study suggests differences in players' performances according to age group and players' role in different qualities of opposition. The article provides reference values that can be useful to guide training and create scenarios that resemble a competition, taking into account physical and temporal characteristics. Key PointsPlayer roles, quality of opposition, and competitive level of the teams influence physical and temporal characteristics, and they may be taken into consideration during the training by strength and conditioning coaches and coaches.More experienced players adopt strategies to better manage their effort and rest time between rallies.The game strategy affects the physical actions done by players (e.g. tendency to serve more to one player of the team affects the number of jumps performed by this player).

Physical actions and work-rest time in men's beach volleyball / Ações físicas e intervalo trabalho-descanso em voleibol de praia masculino / Acciones físicas y tiempos de trabajo-descanso en voley-playa masculino

The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest ratio in male beach volleyball players in relation to their tactical roles. The sample of this study included 6970 rallies played by 91 beach volleyball players, which corresponded to 179 sets of the 2008 Men's Beach Volleyball World Tour (FIVB). We analyzed: ball contacts, jumps, hits, work time, rest time, set (first, second or third), and player's tactical role (e.g., defense specialist, blocker, or no specialization). A significantly higher number of jumps were executed by blockers. No differences were found in the third set for any of the physical variables studied. This paper provides references about the physical demands (e.g., contacts, jumps, and hits for blockers and defense specialists) and temporal patterns of the beach volleyball game (i.e., work and rest time) for two-set matches and three-set matches...

"Ações físicas e intervalo trabalho-descanso em voleibol de praia masculino." O objetivo do presente estudo foi avaliar o número de contatos com a bola, saltos, ataques, tempo de trabalho e descanso em jogadores de voleibol de praia masculino em função da sua especialização. A amostra do estudo foi composta por 6970 rallies, jogados por 91 participantes, correspondendo a 179 sets do Beach Volleyball World Tour (FIVB) de 2008. As variáveis estudadas foram: contatos com a bola, saltos, ataques, tempo de trabalho, tempo de descanso, set (1º, 2º e 3º) e especialização do jogador (defensor especialista, bloqueador, ou não especializado). Um número significativo de saltos foi realizado pelos bloqueadores. Não foram encontradas diferenças significativas no 3º set para qualquer uma das variáveis estudadas. Este estudo apresenta valores de referência acerca das demandas físicas (contatos, saltos e ataques realizados por bloqueadores e defensores especialistas) e dos padrões temporais do jogo de voleibol de praia (tempo de trabalho e descanso) para jogos de dois e três sets...

"Acciones físicas y tiempos de trabajo-descanso en voley-playa masculino." El objetivo de este estudio fue medir el número de contactos con el balón, saltos, golpeos, el tiempo de trabajo y de descanso de jugadores de voley-playa masculino en función de su rol de juego. La muestra de estudio estuvo compuesta por 6970 jugadas realizadas por 91 jugadores participantes en 179 sets de la Beach Volleyball World Tour (FIVB) de la temporada 2008. Las variables registradas fueron contactos realizadas, saltos, golpeos, tiempo trabajo, tiempo de descanso, set (1º, 2º, o 3º), and función de juego (bloqueador, especialista en defensa, o universal). Un significativo mayor número de saltos fueron realizados por los bloqueadores. No se encontraron diferencias en el tercer en ninguna de las variables físicas estudiadas. Este trabajo presenta valores de referencias de las demandas físicas (balón, saltos, golpeos) y parámetros temporales (tiempo de trabajo y de descanso) del juego del voley-playa para partidos de dos sets y de tres sets...

Systematic review on sports performance in beach volleyball from match analysis / Revisão sistemática sobre a performance desportiva no voleibol de praia a partir da análise do jogo

The present article aimed to perform a systematic review of the available literature in relation to the analysis of sports performance in beach volleyball from match analysis. Web of Science, SportDiscus(, PubMed, Scopus and Academic Search Complete databases were used to identify peer-reviewed published articles. The authors conducted a content analysis according to goals, variables of analysis and methods used in studies. In general, three research lines were determined: analysis of the functional dependence of the game actions and their relation with success, performance according to gender, and the effect of changing the rules on the game performance. In relation to methodology, an evolution from descriptive studies to studies of comparative nature can be seen and, more recently, there has been a focus on predictive nature. This new trend breaks with the research based on simple cause and effect relations , and focuses on the analysis of the game events, namely related to tactical-technical performance indicators, in a non-linear and interactive way, considering the game as a complex and dynamic system. The limitations of the studies analyzed show the need for further studies to in vestigate the identification of game patterns for the different game levels; integration of situational variables in the study of the performance of teams (such as match status and the quality of opposition).

O objetivo deste estudo consistiu numa revisão sistemática da investigação empírica realizada sobre a performance desportiva no voleibol de praia a partir da análise do Jogo. As bases de dados Web of Science, SportDiscus(, PubMed, Scopus e AcademicSearch Complete foram utilizadas para identificar os artigos empíricos com revisão de pares publicados. Procedeu-se a uma análise de conteúdo em função dos objetivos, variáveis de análise e métodos utilizados nos estudos. Em termos gerais, emergem três linhas de investigação: a análise da dependência funcional das ações de jogo e a sua relação com o sucesso, a performance em função do sexo e o efeito da mudança das regras na performance do jogo. Ao nível metodológico, destaca-se uma evolução de estudos descritivos para comparativos e mais recentemente, um enfoque de natureza preditivo. Esta nova tendência rompe com a análise do jogo baseada em relações simples de causa e efeito e aponta para a análise dos eventos do jogo, nomeadamente, ao nível dos indicadores tático-técnicos da performance, de forma não linear e interativa, considerando o jogo como um sistema complexo e dinâmico. As limitações patentes nos estudos analisados projetaram a necessidade de se investigar no futuro: a identificação de padrões de jogo para os diferentes níveis de jogo; a integração de variáveis situacionais no estudo da performance das equipes (isto é, o resultado no momento e a qualidade de oposição).

Match Duration and Number of Rallies in Men's and Women's 2000-2010 FIVB World Tour Beach Volleyball.

After the 2000 Olympic Games, the Fédération Internationale de Volleyball (FIVB) modified the scoring system used in beach volleyball from side-out to a rally point system. The goal was to facilitate the comprehension of the game and to stabilize match duration. The purpose of this study was to assess the duration and number of rallies in men's and women's beach volleyball matches (2000-2010 FIVB World Tour). Data from 14,432 men's matches and 14,175 women's matches of the 2000-2010 World Tour were collected. The variables studied were: match duration, total rallies per set and match, number of sets, team that won the set and match, type of match (equality in score), and gender. The average match duration in beach volleyball is stable, ranging from 30 to 64 minutes, regardless of the number of sets, the stage of the tournament (qualifying round or main draw), or gender. The average number of rallies per match were 78-80 for two-set matches and 94-96 for three-set matches. Matches from the main draw are more balanced than matches from the qualifying round. More balanced matches (smaller point difference between teams) have longer durations. It is not clear why there is no relationship between the number of rallies and match duration. Future studies are needed to clarify this aspect. The results can serve as a reference to guide beach volleyball training (with regard to duration and number of rallies) and to help understand the effect of the rule change.

Determining the optimal load for resisted sprint training with sled towing.

An excessive load in resisted sprint training can produce changes in running patterns. Therefore, load control is essential to ensure the specificity of these training methods. The most common way to control it is through the percentage of velocity lost in relation to maximum velocity. The present paper describes a study that aimed to establish the load for sprint training with sled towing. The study developed a regression equation for calculating the load in the maximum velocity phase. The calculation was done with 26 athletes from the Spanish and French national levels on a synthetic track surface and with spikes. The regression equation obtained was % body mass = (-0.8674 x % velocity) + 87.99. The equation, although specific for type of surface used and sled towing characteristics, is useful in establishing the optimal load for acceleration and maximum velocity training with sled towing.

Preferences and levels of satisfaction in technical and tactical actions and in type of offense and defense utilized in competition by youth basketball players

The purposes of the present study are: a) to assess which technical and tactical actions of the game youthbasketball players like to do in competition at different learning stages, b) to find out how much they like to play offenseand defense, c) to assess the type of offense and defense that they prefer to execute, and d) to record the basic tacticalteam resources (BTTR) that are most requested by the youth player at different learning stages. The sample was composedof 989 youth basketball players who participate in the Spanish Basketball Federation leagues (60.1% from mini-basketballand 39.9% from the under-14 category). The results indicate that in competition: a) the action that players most like toexecute is the shot, b) players prefer to be on offense than defense, c) the defensive game system that players most enjoy isman-on-man defense, d) players prefer pre-established offensive systems as opposed to open systems, and e) basic tacticalteam resources players most enjoy are give-and-go, clear-outs, and penetrate and dish. These data may serve as a referencewhen doing short-, medium-, and long-term planning. In any case, it is necessary for coaches to combine the preferencesof the players with the actual needs of each learning stage(AU)

Percepción de los factores de riesgo de los trastornos alimenticios en jugadoras universitarias de voleibol / Perception of eating disorder risk factors in female college volleyball players

Este estudio aborda los factores de riesgo y el conocimiento de las jugadoras sobre los trastornos alimenticios en jugadoras universitarias de voleibol. La muestra objeto de estudio estuvo compuesta por un total de 50 jugadoras participantes en el Campeonato de España Universitario de 2004-2005. Se realizó un diseño selectivo, descriptivo, y transversal. La información se registró con el cuestionario de alimentación, control de peso, y deporte. El análisis de los datos se realizó a nivel descriptivo (frecuencia y porcentajes). Un 71.5% de las jugadoras indicó estar satisfechas con sus cuerpos, un 45.8% de las jugadoras indicó haber recibido presiones para estar delgadas, un 63.6% de las deportistas indicó haber utilizado medios para el control de su peso, y un 2% de las jugadoras fue diagnosticada con trastornos alimenticios. Seis de cada 10 jugadoras indicó que sus entrenadores son fuentes de información sobre aspectos nutricionales, mientras que únicamente una de cada 10jugadoras indicó que sus entrenadores son fuentes de información sobre los trastornos alimenticios. Los resultados encontrados indican que los entrenadores no tienen un papel activo en la aportación de información y mecanismos de ayuda frente a los trastornos alimenticios. La práctica de voleibol en edad universitaria parece no estar relacionada con un incremento de la ocurrencia de los trastornos alimenticios (AU)

This paper studied the risk factors and player's knowledge of eating disorders in female college volleyball players. Fifty female volleyball players from the 2004-2005 Spanish National University Championship were studied. A selective, descriptive, and transversal design was done. The data was registered with a survey. The data analysis was descriptive(frequencies and percentages). Results showed that 71.5% of subjects were satisfied with their bodies, 45.8% had received pressure to be thin, 63.6% had used methods to control their weight, and 2% had been diagnosed with a clinical eating disorder. Six out of 10 players had received nutritional information from their coaches, however only one out of 10 players had received information about eating disorders. Among this sample, coaches do not have anactive role in giving players information and mechanisms to help prevent eating disorders. Volleyball playing in college does not appear to be related to an increase in eating disorder occurrence (AU)

Analysis of the efficacy of possessions in boys' 16-and-under basketball teams: differences between winning and losing teams.

The purpose of this study was to analyze the ball possessions of winning and losing basketball teams in formative years (16 years and under). The sample was 3,897 ball possessions from 24 games of the boys' 16-and-under finals of the Andalusion Championship, Spain. The variables studied were game outcome, participation, and the initiation and end of each ball possession. Winning teams used more fast breaks and fewer set offenses in their ball possessions. Winning teams had shorter ball possessions and more passes and participating players. Dynamic game styles are necessary in youth basketball, focusing on continuously off-balancing the opponent through fast breaks and a high number of passes in set offenses.