Scoping review of tests to assess tactical knowledge and tactical performance of young soccer players.

This scoping review aimed to systematically map studies/tests for assessing the tactical domain of young soccer players. The study followed the PRISMA-ScR and Joanna Briggs Institute guidelines. The databases searched were Scopus, SPORTDiscus, SciELO, LILACS, and BDTD. The eligibility criteria were defined based on the elements of population, context, and concept, without restrictions on the period, language, and type of publication. Twenty-four papers were included, from 1997 to 2020, totalling 29 tests/instruments for the assessment of the tactical domain, with the majority of studies having an European sample. Twelve terms were used to nominate the tactical component, regardless of the assessment method and approach. Six tests met eight or nine criteria in the critical appraisal: TCTOF, TACSIS Spanish version, Semi-Structured Interview, TCTP-OE, GPET, and FUTSAT. Thus, it is concluded that studies and tests for the assessment of the tactical domain of young soccer players are recent and mainly European; there is no consensus about the adopted terminology; and few tests met the majority of the quality criteria. Therefore, we suggest: a) the construction/adaptation of tests with samples from other continents; b) the use of the proposed criteria; and c) that the terms tactical knowledge and tactical performance are adopted.

Adaptation and Validation of a Test for the Evaluation of Tactical Knowledge in Soccer: Test de Conocimiento Táctico Ofensivo en Fútbol for the Brazilian Context (TCTOF-BRA).

Background: Studies and tests to assess the tactical domain of young soccer players are recent, and few instruments meet the majority of quality criteria. Objective: To adapt and validate the Test de Conocimiento Táctico Ofensivo en Fútbol (TCTOF) for the Brazilian context (TCTOF-BRA). Methods: The article consists of two studies. Study 1 (n = 111) included the translation, theoretical/semantic analysis, back translation, cross-cultural equivalence, and content and face validity (pre-test). In study 2 (n = 768), a theoretical and empirical item analysis was carried out, followed by construct validity [exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and the known-groups method] and reliability (internal consistency and repeatability). Results: In the cross-cultural evaluation, the Coefficient of content validity total (CCVt) of the instrument was 0.96 and in the content validity, the CCVt of the instrument was 0.87. The face validity was confirmed (>95%). After theoretical and empirical analysis, 15 questions were included in the Teste de Conhecimento Tático Ofensivo no Futebol (TCTOF-BRA). The EFA showed a model with adequate fit (KMO = 0.69; Bartlett p < 0.001), with a factor structure considered very good, composed of four factors (decision making, operational tactical principles, collective tactical-technical elements, and rules). The CFA by the Asymptotically Distribution-Free estimation method demonstrated good and very good goodness of fit indices (X 2/df = 1.54, GFI = 0.99, CFI = 0.94, TLI = 0.92, PGFI = 0.71, PCFI = 0.76, RMSEA = 0.03, and ECVI = 0.26). The known-groups method showed significant differences (p < 0.01) and effect sizes varying from small-to-medium to large. With respect to reliability, coefficients of 0.89 (CR) and 0.74 (KR20) for internal consistency and 0.85 for repeatability were found. Conclusion: The TCTOF-BRA presented satisfactory evidence, demonstrating it to be an instrument with valid and reliable measures for the evaluation of tactical knowledge (declarative and theoretical procedural), based on specific knowledge and decision making (cognitive domain), of Brazilian young soccer players from 12 to 17.9 years old.

Tactical Behaviour of Youth Soccer Players: Differences Depending on Task Constraint Modification, Age and Skill Level.

This study aimed to investigate: i) how Small-Sided and Conditioned Games based on different representation and exaggeration modification strategies, from the Teaching Games for Understanding pedagogical principles, affected team performance and exploratory behaviour; and ii) how teams and players of different ages and skill levels were affected by the use of these different modification strategies. In total, forty-eight youth male soccer players participated in the study (U15, n = 24 mean age = 13.06 ± 1.53 years; U17, n = 24 mean age = 16.89 ± 0.11 years). In both categories, players were organized into three groups according to their tactical efficiency level (Group 01 = High Skilled Players (HSP), Group 02 = Intermediate Skilled Players (ISP), and Group 03 = Low Skilled Players (LSP)). The HSP and LSP groups performed two types of Gk+4vs4+Gk Small-Sided and Conditioned Games (SSCGs) based on different representation and exaggeration modification strategies. The first type of SSCGs was modified by structural constraints (Structural SSCG) and the second type was modified by rule manipulation (Manipulation SSCG). Team performance and exploratory behaviour were analysed through the Offensive Sequences Characterization System and Lag Sequential Analysis, respectively. SSCG modification strategies affected differently tactical performance and exploratory behaviour of teams composed of players of different skill levels. It was found that SSCG modification strategy through rule manipulation provided players and teams with a higher level of difficulty, compromising their performance and inhibiting exploratory behaviour. This information is crucial to practitioners wishing to apply more appropriate pedagogical strategies to improve a specific tactical problem using a player-centred and game-based approach.

External Load Variations Between Medium- and Large-Sided Soccer Games: Ball Possession Games Vs Regular Games with Small Goals.

This study compared external load variations between 5 vs 5 and 10 vs 10 sided game formats played under two conditions: (i) a ball possession game with two floaters, and (ii) a regular game with goalkeepers and small goals. Twenty-two professional soccer players participated in this study: four central defenders, four wide defenders, nine central midfielders, three wide forwards, and three strikers. Total distance (TD), running distance (RD), sprinting distance (SD), number of sprints (NS), and player's training load (PL) were recorded by GPS units. Within-format analyses revealed very likely large increases in TD (20.0%, [9.2; 31.9]; effect size (ES): 1.48, [0.71; 2.25]) and RD (130.9%, [20.2; 343.7]; ES: 1.32, [0.29; 2.35]) during the regular game when compared to the ball possession game in the 5 vs 5 format. In the 10 vs 10 format, large increases in TD (27.9%, [17.7; 39.1]; ES: 3.54, [2.34; 4.74]) and PL (27.4%, [12.6; 44.1]; ES: 2.46, [1.20; 3.72]) were observed in the regular condition when compared to the ball possession condition. Between-formats analyses revealed that, in the 10 vs 10 format, when compared to the 5 vs 5 format, RD was very likely larger (123.5%, [33.7; 273.7]), as was SD (195.8%, [20.5; 626.2]). However, very likely large decreases in PL were observed in the 10 vs 10 format (-19.6%; [-29.4; -8.3]) in the ball possession condition. Unclear differences were revealed based on variations in external load variables between formats in the regular condition. Smaller formats reduce the area available for running and sprinting and, thus, may be more adequate for increasing player's training load (based on accelerometer data).

Characterization of the Weekly External Load Profile of Professional Soccer Teams from Portugal and the Netherlands.

The purpose of this study was to analyze the day-to-day variance of a typical weekly external training workload of two professional soccer teams from different countries. Twenty-nine players from two professional teams from Portugal and the Netherlands participated in this study. The players' external load was monitored for 7 weeks, by means of portable GPS devices (10 Hz, JOHAN, Noordwijk, Netherlands). Results revealed that match day -1 (MD-1), i.e. the training day before a match, had significantly (p = 0.001) less training volume (4584.50 m) than the other days. MD-5 (training five days before a match), MD-4 (four days before a match) and MD-3 (three days before a match) were the most intense (390.83, 176.90 and 247.32 m of sprinting distance, respectively) and with large volume (7062.66, 6077.30 and 6919.49 m, respectively). Interestingly, significant differences were found between clubs of different countries (p < 0.05) with the Portuguese team showing significantly higher intensity (sprinting distance) and volume (total distance) in all days with exception of MD-1 than the Dutch team. The results of this study possibly allow for the identification of different training workloads and tapering strategies between countries in relation to volume and intensity. It should be noted, however, that both clubs used a significant tapering phase in the last two days before the competition in an attempt to reduce residual fatigue accumulation.

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

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.

Tactical expertise assessment in youth football using representative tasks.

Specific football drills improve the development of technical/tactical and physical variables in players. Based on this principle, in recent years it has been possible to observe in daily training a growing volume of small-sided and conditioned games. These games are smaller and modified forms of formal games that augment players' perception of specific tactics. Despite this approach, the assessment of players' knowledge and tactical execution has not been well documented, due mainly to the difficulty in measuring tactical behavior. For that reason, this study aims to provide a narrative review about the tactical assessment of football training by using representative tasks to measure the tactical expertise of youth football players during small-sided and conditioned games. This study gives an overview of the ecological approach to training and the principles used for representative task design, providing relevant contribution and direction for future research into the assessment of tactical expertise in youth football.

Developing Talented Soccer Players: An Analysis of Socio-Spatial Factors as Possible Key Constraints.

Most studies on the identification and development of soccer talent have been one-dimensional in nature. Although some multi-dimensional analyses have been conducted, few research studies have assessed in any depth the socio-spatial factors influencing talent development. The aim of this particular study was to analyse variations in the international representation of clubs (n = 821) and countries (n = 59) in the development of players who took part in the 2014 FIFA Soccer World Cup. Clubs and countries were ranked and divided into quartiles according to the number of players developed between the ages of 15 and 21 (clubs and countries that developed players for at least three years between these ages) and the number of official league matches played by these players up to the age of 23. Significant variations were observed between clubs in terms of the number of developed players who took part in the World Cup and the number of official league matches played by these players up to the age of 23 (p < .05), and also between countries (p < .05). The findings reveal the need to carry out more in-depth studies into the type of training and competition engaged in by elite players in the period of development between the ages of 15 and 21. It may be the case that these factors are potentially decisive socio-spatial constraints in the development of soccer talent.

Review of the tactical evaluation tools for youth players, assessing the tactics in team sports: football.

For sports assessment to be comprehensive, it must address all variables of sports development, such as psychological, social-emotional, physical and physiological, technical and tactical. Tactical assessment has been a neglected variable until the 1980s or 1990s. In the last two decades (1995-2015), the evolution of tactical assessment has grown considerably, given its importance in game performance. The aim of this paper is to compile and analyze different tactical measuring tools in team sports, particularly in soccer, through a bibliographical review. Six tools have been selected on five different criteria: (1) Instruments which assess tactics, (2) The studies have an evolution approach related to the tactical principles, (3) With a valid and reliable method, (4) The existence of publications mentioning the tool in the method, v. Applicable in different sports contexts. All six tools are structured around seven headings: introduction, objective(s), tactical principles, materials, procedures, instructions/rules of the game and published studies. In conclusion, the teaching-learning processes more tactical oriented have useful tactical assessment instrument in the literature. The selection of one or another depends some context information, like age and level of expertise of the players.

Game-Based Approaches' Pedagogical Principles: Exploring Task Constraints in Youth Soccer.

This study tested the use of two pedagogical principles of Game-based approaches, representation and exaggeration, in the context of game performance of U10 soccer players. Twenty-one players participated in two 3 vs. 3 small-sided games. The first small-sided game was modified by representation. The second small-sided game was modified by enhancing the penetration of the defense tactical problem for invasion games. Decision-making and execution were assessed using the Game Performance Evaluation Tool. No significant differences were observed between games in the number of decision-making units related to keeping possession, nor in those related to penetrating the defense. No significant differences were observed in any execution ability (ball control, passing, dribbling and get free movements). The findings suggested that both games could provide similar degeneracy processes to the players for skill acquisition (specific and contextualized task constraints in which they could develop their game performance and the capability to achieve different outcomes in varying contexts). Probably both games had similar learner-environment dynamics leading players to develop their capabilities for adapting their behaviours to the changing performance situations. More research is necessary, from the ecological dynamics point of view, to determine how we should use small-sided games in Game-based approaches.