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.

Acquisition of educational values at the Real Madrid Foundation's social-sports schools.

The objective of this study was to analyse the impact of the educational programme of the Real Madrid Foundation (RMF) on the acquisition of educational values at social-sports football and basketball schools among children aged between 12 and 16 years in Italy, Romania, Spain and the United Kingdom. The most significant results showed that: (a) between the 20-21 and 21-22 seasons, there were statistically significant increases in personal and team success, self-fulfilment, personal and group superiority, health and physical fitness, and peaceful behaviour; and (b) the increase in variables being studied was different according to the country analysed in such a way that: in the per-sonal and team success dimension there was a rise in the United Kingdom and Italy; in self-fulfilment there was an increase in the United Kingdom; in the personal and group superiority dimension there was a rise in Italy and Romania; in the health and physical fitness dimension there was an increase in social-sports schools in the United Kingdom and Italy; in the peaceful behaviour dimension there was a rise in social-sports schools in the United Kingdom and a drop in social-sports schools in Romania. There were very significant improvements in the majority of dimensions and countries, although the development of the various dimensions is different and specific to every one of the distinct countries, meaning that it is necessary to keep adapting the educational programme of the Real Madrid Foundation in line with the sociocultural characteristics of each of the countries in which it is implemented.

Perceived self-efficacy by Under-10 tennis players when scaling the equipment and play area.

The modification of child-sports aims to develop an optimal learning environment that facilitates the emergence of desirable psychological outcomes (e.g., self-efficacy). The aim of the study was to assess the effect of reducing net height and court size on self-efficacy and shot-efficacy of U-10 tennis players in a real-game context. Twenty U-10 tennis players (M = 9.46, SD = 0.66 years of age; M = 3.65, SD = 1.53 years of tennis experience) played two round-robin tournaments one week apart in the same order and schedule. The first tournament was played under the International Tennis Federation's Tennis 10s regulation at green stage (GT). Afterwards, the modified tournament (MT) was played with the same regulation GT, however, net height (0.91 m-0.80 m) and court size (23.77 m × 8.23 m-18.00 m × 8.23 m) were reduced. Results accomplished using Bayesian and Frequentist inferences showed an increase in players' self-efficacy when serving in MT than GT (BF10 = 4.796; δ = -0.576; and p = .011). This is increase may be due to a reduction in their serving faults in MT (BF10 = 6.169; δ = -0.591; and p = .010). Therefore, reducing net height and court size enhances the serve performance and self-efficacy and thus promotes positive tennis experiences.

Influence of Rule Manipulation on Technical-Tactical Actions in Young Basketball Players: A Scoping Review.

The purpose of this scoping review was to analyse the effect of rules modification on technical and tactical action in young basketball. The publications search period ranged from January 2007 to December 2021. The search covered the following electronic databases: SCOPUS, SportDiscus, and the Web of Science core collection. Following this search process, 18 articles were included in the review. The following variables were analysed: characteristics of the sample, the constraints manipulated, the duration of the intervention, and the effect on technical-tactical actions. The studies reviewed modified the following constraints: (a) number of players (66.7%), (b) court dimensions (27.8%), (c) ball/player interactions (11.1%), and (d) ball/player interactions, basket height, game time and number of baskets (5.6%, respectively). The findings show that rule manipulation can increase players' participation and promote the variability of players' actions. The current evidence about rule modification in youth basketball presents areas in which more studies are needed to have a complete perspective of their impact in practice and competition through the different stages of players' development. Taking into account individual needs and developmental stages, further studies should consider different age groups (e.g., from U-10 to zU-14) and female players. Expanding scientific knowledge in this area would help coaches make short- and long-term plans in accordance with players' developmental stages.

La visualización en la rehabilitación de lesiones deportivas: una revisión / Guided imaginary in the rehabilitation of sports injuries: a review

La visualización se ha utilizado en programas de intervención psicológica para la rehabilitación de deportistas lesionados ya que diferentes estudios la asocian con una mejoría en el afrontamiento psicológico y reducción de la ansiedad por el temor a volver a lesionarse. Por esto, el objetivo es revisar las publicaciones que utilizan la visualización en la rehabilitación de deportistas lesionados y determinar su eficacia. Se realizó una búsqueda sistemática siguiendo la guía PRISMA, en la Web of Science, usando como palabras clave: sport injur*, psycho* y rehabilitation. Los criterios de inclusión fueron ser un estudio empírico y la aplicación de la visualización en la rehabilitación de la lesión deportiva. Se obtuvieron 394 artículos, que se redujeron a cinco. Los resultados muestran que cuatro trabajos emplean la visualización junto con otras técnicas psicológicas. Se emplearon, en su mayoría, instrumentos de evaluación ad hoc. La visualización se mostró eficaz en cuatro de los cinco estudios, consiguiendo los efectos deseados. Las variables psicológicas más estudiadas fueron el dolor, la adherencia a la rehabilitación, la autoeficacia, la motivación y la ansiedad. Se deduce que la visualización, ha resultado útil en la rehabilitación de lesiones deportivas como parte de un programa de tratamiento integral del deportista lesionado. (AU)

Guided imaginary has been used in psychological intervention programs for the rehabilitation of injured athletes, since different studies associate it with an improvement in psychological coping and a reduction in anxiety due to the fear of being injured again. Therefore, the objective is to review the publications that use guided imaginary in the rehabilitation of injured athletes and determine its effectiveness. A systematic search was carried out following the PRISMA guide, in the Web of Science, using as keywords: sport injury*, psycho* and rehabilitation. The inclusion criteria were to be empirical and the application of guided imaginary in the rehabilitation of sports injury. 394 articles were acquired, which were reduced to 5. The results show that 4 works carried out guided imaginary together with other psychological techniques. Ad hoc evaluation instruments were used for the most part. Guided imaginary was shown to be affective in 4 of the 5 studies, achieving the desired effects. The most studied psychological variables were pain, adherence to rehabilitation, self-efficacy, motivation and anxiety. It follows that guided imaginary has been useful in the rehabilitation of sports injuries as part of a comprehensive treatment program for the injured athlete. (AU)

Effect of changes in the net height, court size, and serve limitations on technical-tactical, physical, and psychological aspects of U-14 female volleyball matches.

Introduction: The objective was to analyze the effect of a reduction of the net height and the court size and serve limitations on the technical-tactical actions, physical actions, and psychological aspects in youth volleyball players. Methods: The sample was 29 under-14 female volleyball players (three regional club teams). A quasi-experimental design was implemented to assess the effect of modification in three tournaments. The independent variables were: a) official rules tournament (no changes in the rules), b) Experimental Tournament 1 (reduction in the net height from 2.10 m to 2 m, no jump serves, and a maximum of two serves per player and rotation), and c) Experimental Tournament 2 (reduction in net height from 2.10 m to 2 m, reduction in court size from 9 × 9 m to 8 × 8 m, no jump serves, and a maximum of two serves per player and rotation). The dependent variables were: ball contact done (type), quality and efficacy of the technical actions, team game phases occurrence, quality and efficacy, continuity index, number of jumps, player's jump load in the take-off and landing, number of hits, average heart rate, Rate of Perceived Effort, time between ball contacts, serve velocity, perceived individual and collective self-efficacy, perceived enjoyment, and perceived satisfaction. Results: Experimental Tournament 1 involved an increase in the efficacy of serves and a decrease in the efficacy of side-out phases. The imbalance between serve and reception did not impact game continuity but reduced the attack and blocks. Experimental Tournament 2 involved a decrease in the efficacy of serves and an increase in the efficacy of side-out phases. The balance between serve and reception increased reception efficacy, the occurrence of attacks and blocks, game continuity, and players' effort. players' effort. Discussion: Scaling the net and court and adapting the serve rules (Experimental Tournament 2) resulted in game dynamics for these U-12 teams that were more similar to those of posterior stages of player through the balance between serve and reception and the adaptation of the net height and court size.

Effect of scaling basket height for young basketball players during the competition: seeking out positive sport experiences.

Proper scaling of sports equipment is necessary to ensure an optimal teaching-learning process . This study aimed to analyse the effect of reducing basket height on the technical-tactical actions, physical participation, self-efficacy, cooperation and enjoyment of young basketball players in the competition. 51 under-14 male basketball players from four teams were chosen as the sample. The data collection included 2,286 attack phases during 12 matches. All players competed in two tournaments using official basketball rules but different basket heights (official basket height, 3.05 metres, and modified basket height, 2.80 metres). The dependent variables were: a) types of shooting actions, shot efficacy, and shooting conditions; b) the duration, type, number of passes done, and efficacy of the attack phases; c) heart rate values; and d) perception of specific and physical self-efficacy, collective efficacy, cooperation, and enjoyment. The results show that the scaled basket promoted game styles that increased the occurrence of fast-breaks and long positional attack phase. Shot efficacy for all shot types improved (not-significantly) and brought change in players' specific self-efficacy and enjoyment. These findings show that scaling equipment can help the transition from mini-basket to regular basket (under-14 age group) by generating better conditions for players' development.

Does Youth Soccer Players' Group Cooperation Improve when Pitch, Goal, and Team Size are Reduced?

The aim of this study was to analyse the effects of the modification of the pitch size, goal size, and the number of players per team on the level of cooperation in youth soccer players (U-12). A quasi-experimental design was implemented to measure the effects of the changes in the number of players per team (8-a-side vs. 5-a-side), goal size (6 x 2 m vs. 3 x 2 m), and field size (58 x 38 m vs. 38 x 20 m) on the cooperation. Four soccer teams under-12 (n = 48 players) participated in three tournaments (standard rules; proposed rules; standard rules). The five variables of cooperation were measured using the "Sports Cooperation Questionnaire": conditional cooperation, cooperation with the coach, disposition of unconditional cooperation, situational cooperation with teammates, and situational cooperation outside the field of play. Players presented the same level of cooperation in conditional cooperation, situational cooperation with teammates, and situational cooperation outside the field of play with both types of rules. The modification of rules involved a reduction of the cooperation with the coach and a disposition of unconditional cooperation. The causes of the reduction may be related to players' adaptation to new tactical dispositions and game situations. Future studies are needed of player's cooperation and different competition rules in youth sports.

Design, Validation, and Reliability of an Observational Instrument for Technical and Tactical Actions in Singles Badminton.

Technical and tactical actions are decisive in terms of badminton player competitive performance. The main objective of this research was to design, validate, and estimate the reliability of an observational instrument for the analysis of the tactical and technical actions in individual badminton. The process was carried out in four different steps: first, there was a review of the scientific literature and a preliminary list of variables was made; second, a qualitative and quantitative assessment was completed by 10 badminton expert judges; in the third step, the content validity was estimated using Aiken's V coefficient; finally, intra-observer reliability and interobserver reliability were tested by two observers specialized in badminton using the Cohen's Kappa coefficient and the intraclass correlation coefficient. Strokes were used as the unit of measure by our observational instrument; every time badminton players hit the shuttlecock, 22 variables (eight contextual variables, seven variables related to the result of the match, and seven variables related to the game) are observed. The minimum Aiken's value was 0.58, and reliability was 0.63. In spite of these values, none of the variables had to be removed, but there were modifications in terms of drafting in some of them. The main findings confirmed the validity and the usefulness of this instrument.

Effect of Scaling Task Constraints on the Learning Processes of Under-11 Badminton Players during Match-Play.

Scaling equipment and the playing space according to junior badminton players' characteristics and needs is a key aspect to design optimal learning environments. The purpose of the study is to analyze the incidence of reducing the court size (from 13.40 m × 5.18 m to 11.88 m × 5.18 m) and net height (from 1.55 m to 1.30 m) for under-11 badminton players on the following technical and tactical variables: (a) service area; (b) stroke effectiveness; (c) kinds of technical strokes; (d) players' hitting area; (e) shuttle landing area; (f) shuttle flight; and (g) rally length. Twenty-eight badminton players (mean age of players: 9.81 ± 0.93) were selected and played a badminton competition (B) with the current federative rules and a mini-badminton competition (MB) with the altered net height and court dimensions. The results showed that a lower net height and a shorter court would increase the frequency and variability of strokes and play patterns, introducing quantifiable changes considered beneficial for children in their first stages, both in training and competition.

Passing Networks and Tactical Action in Football: A Systematic Review.

The aim of this study is to examine the most significant literature on network analyses and factors associated with tactical action in football. A systematic review was conducted on Web of Science, taking into account the PRISMA guidelines using the keyword "network", associated with "football" or "soccer". The search yielded 162 articles, 24 of which met the inclusion criteria. Significant results: (a) 50% of the studies ratify the importance of network structures, quantifying and comparing properties to determine the applicability of the results instead of analyzing them separately; (b) 12.5% analyze the process of offensive sequences and communication between teammates by means of goals scored; (c) the studies mainly identify a balance in the processes of passing networks; (d) the variables allowed for the interpretation of analyses of grouping metrics, centralization, density and heterogeneity in connections between players of the same team. Finally, a systematic analysis provides a functional understanding of knowledge that will help improve the performance of players and choose the most appropriate response within the circumstances of the game.

Changes in Markers of Oxidative Stress and α-Amylase in Saliva of Children Associated with a Tennis Competition.

The purpose of this paper was to analyze the changes caused by a one-day tennis tournament in biomarkers of oxidative stress and α-amylase in saliva in children. The sample was 20 male active children with the following characteristics: (a) age of players = 9.46 ± 0.66 years; (b) weight = 34.8 ± 6.5 kg; (c) height = 136.0 ± 7.9 cm; (d) mean weekly training tennis = 2.9 ± 1.0 h. The tennis competition ran for one day, with four matches for each player. Data were taken from the average duration per match and the rating of perceived exertion (RPE). Four biomarkers of antioxidant status: uric acid (AU), Trolox equivalent antioxidant capacity (TEAC), ferric reducing ability of saliva (FRAS, cupric reducing antioxidant capacity (CUPRAC) and salivary alpha-amylase (sAA) as a biomarker of psychological stress were measured in saliva. The time points were baseline (at home before the tournament), pre-competition (immediately before the first match) and post-match (after each match) measurements. The four biomarkers of antioxidant status showed a similar dynamic with lower values at baseline and a progressive increase during the four matches. Overall one-day tennis competition in children showed a tendency to increase antioxidant biomarkers in saliva. In addition, there was an increase in pre-competition sAA possibly associated with psychological stress. Further studies about the possible physiological implications of these findings should be performed in the future.

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.

Applying the New Teaching Methodologies in Youth Football Players: Toward a Healthier Sport.

At early ages (6-12 years), the levels of physical activity developed in sports initiation and Physical Education often fall short of optimal levels. Ecological models of education seek, among other things, to make up for this deficit by modifying the structural elements of sport, bringing play closer to the child's developmental characteristics. In this sense, Nonlinear Pedagogy is a model of active pedagogy that seeks the integral development of young players through a sport more in line with their abilities, and that for this is based on a system of constraints on the environment, the task and the player himself. However, there are no studies that analyze the effects of these methodologies on the parameters of physical activity at such an early age. The aim of this study was to analyze the impact of a learning methodology based on Nonlinear Pedagogy on health-related levels of physical activity (heart rate) in young football players (U-11). A quasi-experimental study was developed in which three tasks were applied using structural modifications of the football elements related to Nonlinear Pedagogy (modification of the number of players related to situations of inferiority, equality and numerical superiority; dimensions of the field of play). The sample studied was composed of football players, U-11 n = 32), age: 10.35 ± 0.54 years; years of experience: 2.14 ± 0.768 years. The players carried out each task for 10 min. Physical activity levels were measured by controlling heart rate using heart rate monitors (Polar Team2). The results showed very high levels of vigorous and very vigorous physical activity in all the tasks designed. These data show that the use of these new teaching methodologies has an impact on levels of physical activity in accordance with the recommended parameters.

Age-related differences in flexibility in soccer players 8-19 years old.

BACKGROUND: Muscle flexibility is a main component of health-related fitness and one of the basic components of fitness for the performance in some sports. Sport and health professionals require the flexibility profile of soccer to define quantitative aims in the training of flexibility. The aim of this study was to identify age-related differences in lower extremity flexibility in youth soccer players. METHODS: Seventy-two young male soccer players (age: 13.0 ± 3.1 y; body mass: 50.5 ± 15.3 kg; stature 158.2 ± 16.8 cm; BMI: 19.6 ± 2.6 kg/m2) completed this study. Measures of eleven passive hip (hip extension (HE), hip adduction with hip flexed 90°(HAD-HF90°), hip flexion with knee flexed (HF-KF) and extended (HF-KE), hip abduction with hip neutral (HAB) and hip flexed 90°(HAB-HF90°), hip external (HER) and internal (HIR) rotation), knee (knee flexion (KF)) and ankle dorsiflexion (ankle dorsiflexion with knee flexed (ADF-KF) and extended (ADF-KE)) ranges of motion (ROM) were taken. Descriptive statistics were calculated for hip, knee and ankle ROM measured separately by leg (dominant and non-dominant) and age-group (U10, U12, U14, U16 and U19). The data was analysed using a one-way analysis of variance (ANOVA) to examine the interaction of 11 ROM in the different players' age-group. RESULTS: Generally, U10 and/or U12 soccer players obtain the highest mean value in almost all ROM evaluated (U10: HAD-HF [39.6° ± 4.3°], ADF-KE [32.3° ± 4.1°], HER [63.5° ± 5.6°] and HAB-HF90°[64.1° ± 7.5°]; U12: HE [17.7° ± 6.2°], HAB [35.6° ± 3.0], HIR [60.8° ± 4.7°] and KF [133.8° ± 7.1°]). Nonetheless, significant differences between the players' age-groups are just found in HAD-HF90°(p = .042; ES = .136), HAB (p = .001; ES = .252), HIR (p = .001; ES = .251), HER (p < .001; ES = .321) and HAB-HF90°(p < .001; ES = .376) ROM, showing a progressive and irregular decrease in these ROM until the U19 team. CONCLUSION: The findings of this study reinforce the necessity of prescribing exercises aimed at improving HAD-HF90°  ROM in U16, HAB ROM in U14, HIR ROM in U16 and U19, HER ROM in U12 and U19, and HAB-HF90°  ROM in U16 and U19 players within everyday soccer training routines.

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.

Differences in the Offensive and Defensive Actions of the Goalkeepers at Women's FIFA World Cup 2011.

The aim of this study was to analyze the technical and tactical offensive and defensive actions of the goalkeepers and to determine the relationship between these actions and the qualifying results of their respective teams. The sample studied is made up of the goalkeepers (n = 20) of the senior national teams that participated in the FIFA Women's World Cup in Germany 2011. A descriptive analysis was developed comparing the offensive and defensive actions in competition carried out by the goalkeepers on qualified teams (pass the group stage) with the goalkeepers on unclassified teams (not pass the group stage). For the inter-group comparison, the value of the coefficient of variation was incorporated and the effect size calculated. All data were treated with a statistical significance level of p < 0.05. The results show that the goalkeepers on qualified teams have higher offensive registers, as well as a higher number of passes successfully completed in different areas of the field. The goalkeepers on unclassified teams show higher defensive records such as saves inside the area, foot stops and wrong clearances among others.

Effect of Modification Rules in Competition on Technical-Tactical Action in Young Tennis Players (Under-10).

Adapting competitions to young players' characteristics is an important pillar in the optimal teaching-learning process. The objective of the present study is to analyze the effect of modifying net height (from 0.91 to 0.80 m) and court dimensions (from 23.77 × 8.23 m to 18 × 8.23 m) for under-10 (U-10) tennis players on the following: (a) kinds of technical and tactical basic, situational, and special strokes; (b) tennis players' hitting area; (c) landing location of the serve; (d) ball landing location after the serve; (d) stroke effectiveness; and (e) rally length. The study design was quasi-experimental in nature, observing the fluctuation/change in technical-tactical variables of the tennis players when playing a "Tennis 10s Green Competition" (GC) with the current federative rules and a redesigned competition "Modified Competition" (MC) including altered net height and court dimensions based on small-sided games (SSGs) and equipment scaling. Twenty U-10 tennis players were studied (age of players = 9.46 ± 0.66 years, average weekly training in tennis = 2.90 ± 1.07 h, years of experience = 3.65 ± 1.53 years). The results showed that in MC, there was a greater technical-tactical variability compared with the GC in terms of the following: (a) greater service effectiveness; (b) more situational and special strokes; and (c) a more equitable change in the distribution of hitting and ball landing locations. The values of MC showed that the current adaptation rules and equipment in federated U-10 competitions might not be enough to improve the teaching-learning process under the comprehensive approach. The current competition for U-10 tennis players (stage green) should be redesigned, in order to build an optimal process of affordances to develop a multidimensional positive impact during this training stage.

Relación entre Edad y Criterios de Rendimiento y Participación en Jugadores de Baloncesto de Alto Rendimiento / Relationship between Age and Performance and Participation in High Performance Basketball Players / Relação entre idade e desempenho e participação em jogadores de basquetebol de alto desempenho

El objetivo del presente estudio fue analizar la edad a la que los jugadores de baloncesto de alto rendimiento obtienen los mejores valores de participación y de rendimiento deportivo. Para ello se analizaron el total de jugadores de la liga ACB de baloncesto participantes en la liga regular desde la temporada 2005-2006 hasta la temporada 2017-2018 con el requisito de haber disputado un mínimo de 5 minutos en al menos 5 partidos (n = 2973). Se dividió a la muestra total en cuatro grupos de edad: a) hasta 25 años, b) 25.1 y 28 años, c) de 28.1 a 31 años, y d) mayores de 31 años. De cada uno de los jugadores se registraron los datos estadísticos que fueron clasificados en dos grupos: a) variables relacionadas con la participación, y b) con el rendimiento. Los resultados indican que, en la participación, son los menores de 25 años los que destacan por ser el único rango de edad por debajo de la media general; mientras que, desde la perspectiva del rendimiento, son los jugadores más veteranos los que obtuvieron mejores resultados

The objective of the present study was to analyse the age at which high performance basketball players obtain the best values of participation and sports performance. Total number of players in the ACB basketball league participating in the regular season was analysed from the 2005-2006 season until the 2017-2018 season with the requirement of having played a minimum of 5 minutes in at least 5 matches (n = 2973). The total sample was divided into four age groups: a) up to 25 years, b) 25.1 and 28 years, c) from 28.1 to 31 years, and d) over 31 years. Statistical data were recorded from each of the players and classified into two groups: a) variables related to participation, and b) performance. The results indicate that, in the participation, it is the under-25s who stand out as the only age range below the general average; whereas, from the perspective of performance, it is the oldest players who obtained the best results

O objetivo do presente estudo foi analisar a idade em que jogadores de basquetebol de alto rendimento obtêm os melhores valores de participação e desempenho esportivo. Para este fim, o número total de jogadores de basquete da ACB que participam da liga regular da temporada 2005-2006 até a temporada 2017-2018 foi analisado com a exigência de ter jogado um mínimo de 5 minutos em pelo menos 5 partidas (n = 2973). A amostra total foi dividida em quatro grupos etários: a) até 25 anos, b) 25,1 e 28 anos, c) de 28,1 a 31 anos ed) com mais de 31 anos. Dados estatísticos foram registrados de cada um dos jogadores, os quais foram classificados em dois grupos: a) variáveis relacionadas à participação eb) desempenho. Os resultados indicam que, na participação, são os menores de 25 anos que se destacam como a única faixa etária abaixo da média geral; enquanto, do ponto de vista do desempenho, os jogadores mais veteranos obtiveram os melhores resultados

Design and Validation of an Observational Instrument for the Technical-Tactical Actions in Singles Tennis.

The competitive performance in tennis practice is determined by the effectiveness of technical tactical action. The main objective of the present study was to design and validate an observational instrument with the aim of analysing the technical-tactical in singles tennis. The instrument uses the stroke as a unit of measure, so that each time a player hits a ball, a total of 23 variables are analyzed. The variables collect information about: (a) matching context; (b) result; and (c) technical-tactical information of the stroke (five variables: sequences of the stroke of the point, kind of technical and tactical stroke, bounce area, hitting, and effectiveness area). The design and validation of the instrument consisted on five different stages: (a) review of the scientific literature and variables definition by experts, (b) pilot observation study, (c) qualitative and quantitative assessment of the instrument by experts, (d) review and confirmation of the instrument by experts (content validity), and (e) observation training and reliability evaluation. From 23 expert judges, divided into three panels, and four observers the instrument went from being composed of 38 variables (eight contextual, seven related to the result and 23 related to the game) to 23 (eight contextual variables, 10 of result and five of game), with minimum Aikens's V values of 0.94 and reliability of 0.81. The results show that the designed instrument allows obtaining valid and objective information about the technical-tactical actions of the players and their performance in singles tennis.