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(a). U9-teams: 5 vs. 5; (b). U11-teams: 8 vs. 8; (c): U13-U19-teams: 11 vs. 11.
Source publication
The present study aimed to investigate positional differences in 744 high-level soccer players, aged 8 to 18 years. Players were assigned to six age groups (U9–U19) and divided into four playing positions (goalkeeper (GK), defender (DEF), midfielder (MF) and attacker (ATT)). MANOVA and effect sizes were used to examine anthropometrical and function...
Contexts in source publication
Context 1
... Belgium, youth competitions start in August and end in May, so players were measured during the first competition phase before the winter break. All youth categories (U9-U19) from the two involved soccer clubs played according to a certain tactical system, as suggested by the Royal Belgian Football Association (KBVB) (Figure 1(a-c)). According to the number of players on the field, different tactical systems or formations are used. ...
Context 2
... to the number of players on the field, different tactical systems or formations are used. Teams from the U9-age category play 5 vs. 5 in a "diamond" formation with, besides the GK, 1 DEF, 2 MFs and 1 attacker (ATT) on a 35 m × 25 m pitch (Figure 1(a)). Players from the U11 age category play 8 vs. 8 in a "double diamond" formation with 3 DEFs, 3 MFs and 1 ATT (Figure 1(b)). ...
Context 3
... from the U9-age category play 5 vs. 5 in a "diamond" formation with, besides the GK, 1 DEF, 2 MFs and 1 attacker (ATT) on a 35 m × 25 m pitch (Figure 1(a)). Players from the U11 age category play 8 vs. 8 in a "double diamond" formation with 3 DEFs, 3 MFs and 1 ATT (Figure 1(b)). The older-age categories (from U13) play 11 vs. 11 in a "4-3-3" formation with 4 DEFs, 3 MFs and 3 ATTs as illustrated in Figure 1(c). ...
Citations
... This might be considered surprising since research has highlighted creativity (which is inextricably linked with X-factor) is an important factor for player selection in youth soccer [53] and is directly linked to game performance and progressing into later rounds of senior tournament competitions [54]. Despite soccer player creativity being perceived vital for creating chances, scoring goals and a key principle of play [55], it is mainly associated with attacking players [56,57]. Given that the present study's objective was to create a general soccer specific tool which can be used across playing positions, the perceived importance assigned by the surveyed practitioners may be influenced by playing position bias and/or philosophy. ...
... Given that the present study's objective was to create a general soccer specific tool which can be used across playing positions, the perceived importance assigned by the surveyed practitioners may be influenced by playing position bias and/or philosophy. This may have influenced the present study's survey response data as many practitioners might downplay the importance of X-factor if they perceive this attribute to be 'more useful' in some playing positions but less in others [56]. Despite some youth soccer coaches stating that players ability to show creativity in one-versus-one scenarios was a defining key performance indicator during talent identification, others may believe that defending isn't a priority until later in the youth development phase (under-12 to under-16) and therefore focus their training on inpossession techniques [9], which could suggest X-factor is valued by youth team practitioners regardless of playing position. ...
The aim of this research was to assess the validity and reliability of a newly developed scoring tool, designed for monitoring youth soccer players during match-play performance to support coaches/scouts with the talent identification process. The method used to design the Hull Soccer Behavioural Scoring Tool comprised of a five-stage process of (i) conducting an initial literature review to establish content validity (ii) gaining content validity through a cross sectional online survey (iii) establishing face validity via expert coach feedback (iv) conducting inter-rater reliability tests and (v) intra-rater reliability tests. In stage two, twenty-two soccer academy practitioners completed an online survey, which revealed that player behaviours such as resilience, competitiveness, and decision making were all valued as the most important behavioural characteristics by practitioners (90.9%), whilst X-factor was valued as least important by a significant amount (27.2%). Stages three to five of the testing procedure included a sample of four academy coaches not involved in the preceding stage. Twenty male collegiate soccer players (under-16 to under-18) involved in the study took part in four versus four small-sided games (SSG) in a ‘round-robin’ tournament across three weeks which accumulated 14 SSG’s, 100–140 minutes of playing time and 70–98 individual player grades. Two of the four academy coaches watched the SSG’s and used the Hull Soccer Behavioural Scoring Tool to assess live evidence of desirable player behaviours, which was subsequently followed by retrospective video analysis for intra-rater reliability testing. The remaining two academy coaches watched the same SSG retrospective video footage to test for inter-rater reliability. Reliability results revealed an acceptable level of agreement with scores between 81.25%—89.9% for inter-rater whilst intra-rater provided scores between 80.35%—99.4%. Preliminary evidence here suggests that the Hull Soccer Behavioural Scoring Tool is both a valid and reliable method to assess desirable player behaviours during talent identification processes. Thus, youth soccer practitioners and researchers should seek to test and further validate the tool in order to confirm its utility as a means of measuring behavioural characteristics of youth soccer players.
... Similarly, several studies have identified disparities in sprint performance across different positions. Forwards have been found to have faster sprint times (10 to 30 m) compared to defenders, midfielders and goalkeepers, while goalkeepers generally exhibit lower sprint performance compared to other field positions (Deprez et al., 2014;Haugen et al., 2012Haugen et al., , 2013Slimani & Nikolaidis, 2017). ...
... For example, F and WM often engage in aerial duels in the offensive zones, where jumping ability can be crucial for scoring goals. On the other hand, GK requires specific jumping skills for saves involving sideways jumps or countermovement jumps, necessitating a focus on developing jumping abilities (Deprez et al., 2014;Hervéou et al., 2018). The lower jump performance observed in goalkeepers could be attributed to the nature of their actions during matches, where nearly all jumping movements involve trunk and upper limb engagement, resulting in a more significant impulse (Hervéou et al., 2018). ...
... The sprint performance results of our study align with previous studies conducted on soccer players. The mean values of T 10 and T 30 fall within the reported range for elite soccer players (1.73 to 2.27, and 3.5 to 5 s, respectively) (Deprez et al., 2014;Sporis et al., 2009). ...
... According to White et al. 5 and perez-arroniz et al. 1 there have been 10 studies on adolescent GKs. 6,[10][11][12][13][14][15][16][17][18] However, most studies were about anthropometrics, jump tests, aerobic capacity, and simple agility in a stadium; therefore, the examiner was required to measure time using a handheld stopwatch. However, our pilot study revealed sufficient high-level agreement of running times measured by two examiners with handheld and photocell stopwatches (intraclass correlation coefficient [ICC] (3,1)=0.98, ...
Background:
There is a lack of objective measures and assessments of goalkeeping proficiency and performance in the literature. Furthermore, no reports have focused on adolescent goalkeepers (under the age of 15). The aim of this study was to determine the reliability and validity of the Goalkeeper Reactive Agility Test for Adolescents (GRATA).
Methods:
Content validity was assessed by seven experts and the Item-Content Validity Index (I-CVI) was calculated. We used similar settings to an agility test for college-aged goalkeepers, although the number of repetitions and running direction of the latter parts of the test were modified (number of repetitions: from 3 to 2; running direction: from forward to backward). Eighty-five adolescent male goalkeepers (age: 13.4 years) performed the test three times. The intraclass correlation coefficient (ICC) was used for relative reliability and the standard error of measurement (SEM) and the smallest worthwhile change (SWC) for absolute reliability.
Results:
The I-CVI was 0.86, above the acceptable level of 0.78. The mean running time of the GRATA was 11.98 s. The ICC value was 0.91 (P<0.01; 95% confidence interval [95% CI]: 0.87-0.94), the SEM 0.26 s and the SWC 0.17 s.
Conclusions:
Our results demonstrate that the GRATA has sufficient reliability and content validity in adolescent GKs.
... In addition, it is very difficult to achieve significant results without scientific methods and tools [8]. Many studies around the world are increasingly interested in the anthropometric, physiological and performance profiles of young footballers [9][10][11][12][13][14][15][16][17][18]. It emerges that performance is correlated with anthropometric parameters; they vary with the age category and each game position requires specific characteristics for better performance. ...
... U17 participants of our study (175.4 cm and 66.5 kg) were also taller and heavier than the chineses, belgians and algerians U17 [10,16,27,30] respectively. While the height of young Algerians aged 15 and 16 (168.5 ...
Introduction: This study aimed at examining the anthropometry, physiological parameters and performances of young footballers recruited and formed in Cameroon without data base and physical fitness assessments. Methods: 128 young soccer players from two training structures subdivided into 3 categories (46 U13, 41 U15 and 41 U17) and 6 playing positions participated in this study. Their height, body mass, body mass index (BMI), blood pressure and resting heart rate were determined prior to the linear sprints test (10m and 20m), vertical jump, and Léger's shuttle run test over 20m. Data analysis and comparisons between categories and playing positions have been carried out using Statview 0.5. Differences were considered significant for p < 0.05. Results: The mean values of anthropometric parameters and blood pressure significantly increased with age category whereas resting heart rate decreased. Central defenders and goalkeepers were respectively tallest and heaviest. In general, performances increased significantly from U13 to U15 and tend to stagnate between U15 and U17 with no significant difference between playing positions. Conclusion: This study provided preliminary references in the identification and follow up of young cameroonian talents belonging to their age categories and playing positions. Developing aerobic endurance is the main emergency particularly for U17 players.
... The aim of this study was to examine situational differences in 90° cuts, 135° cuts and 180° pivot turns in games with respect to different playing positions in youth soccer players during games. Previous studies have discovered differences between playing positions in physical demands and agility (Deprez et al., 2015;Granero-Gil et al., 2020). This is the first study to analyze the frequency of CODs commonly used in COD testing protocols in youth soccer games, including differences by player positions. ...
Change of direction (COD) maneuvers in soccer create tactical advantages, but also expose the player to an increased risk of injury. COD ability is commonly tested with pre-planned drills including cuts greater than 90°. These tests do not take into consideration positional differences players encounter during games. This case-series study used principal component analysis (PCA) to examine situational differences during COD movements between playing positions in youth soccer games. For each of the four teams included (26 females, 27 males), one game was analyzed using video-analysis. Two independent reviewers identified situational patterns and a PCA was used to examine differences between playing positions. Three principal components explained 89% of the variation in the data and were categorized as the total quantity of CODs, attacking/goal-scoring and defensive reacting types of CODs. One-way ANOVA on the individual principal component (PC) scores showed significant differences (p < 0.05) between centre midfielders, goalkeepers, and centrebacks in the quantity of CODs (PC1), and between wingers and fullbacks and centre backs in attacking/goal-scoring CODs (PC2), whereas PC3 was not different between playing positions. Differences between playing positions suggest that training and testing protocols in soccer could be enhanced to better match the individual and playing position-based needs.
... COD ability can also be masked by straight sprinting speed [6] and COD movements within a game are dissimilar because of flux in playing situations. Previous research has shown that the requirements for high-speed running, total distance, and CODs are position-specific [8][9][10], but little is known about the situational factors involved in COD maneuvers that could increase biomechanical demands during the final foot contact. The analysis of biomechanical variables during CODs in a game would provide more specific information on the physical demands of gameplay and better guide training and testing tasks to match game requirements. ...
The aim of this study was to assess center of mass (COM) acceleration and movement during change of direction (COD) maneuvers during a competitive soccer game to elucidate situation-specific demands of COD performance. This information can assist in developing soccer-specific tests and training methods. Fifteen elite-level female youth soccer players were tracked for one game with inertial measurement units (IMU) attached to the lower back. COD movements in combination with situational patterns were identified using high-speed video. LASSO regression was used to identify the most important predictors associated with higher vertical peak accelerations (PAv) of the COM during COD movements. COD angle, running speed, contact, and challenge from the opposition were identified as important features related to higher PAv. This study adds to the literature on the demands of COD performance in soccer match-play. The unique approach with game-specific situational data from female youth players provides increased insight into the game-demands of COD and agility performance. PAv in games was higher with larger COD angles, increased running speed, or with contact when the player was challenged by the opposition. A larger study including more games is warranted to increase confidence in using these variables as a basis for training or testing agility.
... Talent identification and development research has typically involved studying components in isolation, including the assessment of anthropometric and physiological variables (Deprez et al., 2015;Gravina et al., 2008;Mirkov et al., 2010;Towlson et al., 2017), technical skills (Huijgen et al., 2013;Keller et al., 2016;Larkin & O'Connor, 2017;Waldron & Worsfold, 2010), tactical skills (Christensen, 2009;Kannekens et al., 2009Kannekens et al., , 2011Olthof et al., 2015) and psychological characteristics (Christensen, 2009;Coetzee et al., 2006;Holt & Dunn, 2004;Höner & Feichtinger, 2016;Miller et al., 2015;Van Yperen, 2009;Zuber et al., 2015). ...
... Previous research has typically focused on four aspects of talent identification and development (anthropometric and physiological, technical skills, tactical skills and psychological variables) (Huijgen et al., 2013;Deprez et al., 2015;Kannekens et al., 2009;Towlson et al., 2017). The current study supports previous research, by including anthropometric and physiological, technical skills, tactical skills and psychological variables in the WDA models. ...
... Specific attributes of GKs have not typically been the focus of previous talent identification or development research (Larkin & O'Connor, 2017;Roberts et al., 2019). For example, previous research has used the same tests to understand performance for both GK and outfield players (Deprez et al., 2015;Le Gall et al., 2010;S. M. Gil et al., 2014;Towlson et al., 2017). ...
... Overall, extensive studies in youth regarding topics such as functional capacities [7][8][9], training methods efficacy [10,11], and talent identification [12,13] have been conducted. Meanwhile, the health-related benefits of recreational soccer participation have also been reported [14,15]. ...
Sports participation is one of the most popular forms of physical activity among youngsters. This study aimed to examine the changes in the estimated body composition, strength, and flexibility of adolescent boys after 12 months of soccer training compared with those of age-matched controls with non-sports participation. We assessed 137 boys (62 soccer players and 75 controls) at baseline (TM1) and 12 months later (TM2). The differences in estimated body composition, strength, and flexibility were investigated using a repeated measure analysis of variance. The analysis revealed a significant main effect of soccer training on fat mass (F = 73.503, p ≤ 0.01, η2 = 0.59) and fat-free mass (F = 39.123, p ≤ 0.01, η2 = 0.48). Over time, the soccer group decreased their fat mass and increased their fat-free mass, while the opposite results were observed for the controls. Among physical fitness tests, a substantial effect of soccer training was evidenced for the sit-up performance (F = 16.224, p ≤ 0.01, η2 = 0.32). Regarding the time factor, significant effects were noted for height and handgrip strength. No significant differences were detected for flexibility. Overall, the benefits of soccer training were exhibited by the larger improvements in fat mass, fat-free mass, sit-ups, and handgrip strength performance, underlining the important role of soccer participation during adolescence.
... Team sport athletes complete a battery of performance tests at the commencement of the preseason preparation period, that often include the Yo-Yo intermittent recovery test (Schmitz et al. 2018), and 30-15 intermittent fitness test (Buchheit and Mendez-Villanueva 2013), amongst other measures of strength, power and change of direction speed (Robertson, Woods, and Gastin 2015). While these testing protocols have been shown to effectively assess individual physical fitness characteristics (Thomas, Dawson, and Goodman 2006;Scott et al. 2015), discriminate between playing standard ) and position (Michalsik, Madsen, and Aagaard 2014;Deprez et al. 2015), and are associated with match running performance Souhail et al. 2010) and promotion to elite competition among youth athletes (Robertson, Woods, and Gastin 2015;Pyne et al. 2005), little is known about the efficacy of any cycling exercise testing protocols and their relationship with gamerunning performance in elite team sport. ...
... The peak of accelerated growth in stature is typically referred to as peak height velocity (PHV) [10][11][12][13], and is often used as a growth landmark in which to assess maturity timing of adolescent soccer players [6,[14][15][16][17]. Using PHV as an identifiable reference point to assess player maturity timing is of relevance and importance to academy practitioners, given that players who undergo PHV earlier (i.e., achieve PHV earlier than peers) are often characterised as possessing temporary, enhanced stature, body-mass and key physical fitness (i.e., speed, power) characteristics are typically over-represented within academy programmes [3][4][5]. Such selection bias are often to the detriment of later maturing players, who may well be equally technically talented, but are less likely afforded a equitable playing environment in which to demonstrate their ability. ...
... The confounding influence of maturation on youth soccer player (anthropometric, physical, technical, tactical, and psycho-social) characteristics which are considered important by practitioners [1,2] during talent identification and athletic processes are well-documented [3][4][5][6][7]. programmes and understand the methods employed, the intended objectives, and the potential barriers to bio-banding. ...
... The over-selection of early maturing, adolescent soccer players who possess (often temporary) enhancements in anthropometric and physical fitness characteristics in favour of their less mature counterparts (who are often characterised as being smaller and having inferior physical characteristics) is well-documented [3][4][5]. Findings here offer explanation for the possible causes for this selection phenomena, by revealing consensus among practitioners that the individual timing of PHV confounds their ability to identify talented soccer players when using a multi-displinary approach (i.e., physical, technical, tactical, and psycho-social characteristics) for talent identification and development. The implementation of innovative player development frameworks (such as the EPPP [36]) which mandate professional soccer academy programmes to systematically monitor the maturity status of its players has enhanced the utilisation of maturity estimations methods such as percentage estimated final adult height (i.e. ...
The primary aims of this study were to examine the application of maturity status bio-banding within professional soccer academy programmes and understand the methods employed, the intended objectives, and the potential barriers to bio-banding. Using a mixed method design, twenty-five professional soccer academy practitioners completed an online survey designed to examine their perceptions of the influence of maturation on practice, their perceptions and application of bio-banding, and the perceived barriers to the implementation of this method. Frequency and percentages of responses for individual items were calculated. In the next phase of the study, seven participants who had experience with, or knowledge of, the bio-banding process within an academy youth soccer setting were recruited to complete a semi-structured interview. Interview data was transcribed and analysed using a combination of deductive and inductive approaches to identify key themes. The main findings across the two phases of the study were that [1] there is consensus among the practitioners that the individual effect of maturation impacts their ability to accurately assess the soccer competencies, [2] the majority (80%) of the sample had implemented bio-banding, with practitioners showing a clear preference for using the Khamis and Roche method to bio-band players, with the greatest perceived benefit being during maturity-matched formats, specifically for late or post-PHV players, [3] Practitioners perceived that bio-banding enhances their ability to assess academy soccer players, and [4] practitioners who have used bio-banding believe that the method is an effective way of enhancing the perception of challenge thereby providing a number of psycho-social benefits. Findings suggest that a collaborative and multi-disciplinary approach is required to enhance the likelihood of bio-banding being successfully implemented within the typical training schedules across the adolescent phase of the player development pathway.
