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.

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.

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.

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.