Academy Football Research Articles

Marker location and knee joint constraint affect the reporting of overhead squat kinematics in elite youth football players

ABSTRACT Motion capture systems are used in the analysis and interpretation of athlete movement patterns for a variety of reasons, but data integrity remains critical regardless. The extent to which marker location or constraining degrees of freedom (DOF) in the biomechanical model impacts on this integrity lacks consensus. Ten elite academy footballers performed bilateral overhead squats using a marker-based motion capture system. Kinematic data were calculated using four different marker sets with 3DOF and 6DOF configurations for the three joint rotations of the right knee. Root mean squared error differences between marker sets ranged in the sagittal plane between 1.02 and 4.19 degrees to larger values in the frontal (1.30–6.39 degrees) and transverse planes (1.33 and 7.97 degrees). The cross-correlation function of the knee kinematic time series for all eight marker-sets ranged from excellent for sagittal plane motion (>0.99) but reduced for both coronal and transverse planes (<0.9). Two-way ANOVA repeated measures calculated at peak knee flexion revealed significant differences between marker sets for frontal and transverse planes (p < 0.05). Pairwise comparisons showed significant differences between some marker sets. Marker location and constraining DOF while measuring relatively large ranges of motion in this population are important considerations for data integrity.

Screening to Detect Hip and Groin Problems in Elite Adolescent Football (Soccer) Players - Friend or Foe?

Injury prevention strategies in team settings should not overlook early detection and secondary prevention. Monitoring systems may be an effective approach to detect common and troublesome injuries, such as hip and groin pain in football (soccer) players. The purpose of this International Perspective is to share our experiences with monitoring hip and groin pain in youth academy football and discuss challenges that surfaced. We consider why players may not accurately report pain, their perceptions of groin pain, and whether all groin pain is clinically meaningful.Level of Evidence5

Part 2 of the 11+ as an effective home-based exercise programme in elite academy football (soccer) players: a one-club matched-paired randomised controlled trial

ABSTRACT Background:Although the 11+ is known to reduce injuries and improve performance in adolescent footballers, its duration presents a notable barrier to implementation. Hence, this study investigated injury and performance outcomes when 65 elite male academy footballers either performed Part 2 3x/week at training (TG) or at home (HG). Methods:Time to stabilisation (TTS), eccentric hamstring strength (EH-S) and countermovement jump height (CMJ-H) were collected 4 times during the 2019 football season. Linear mixed models were used to evaluate main and interaction effects of group and time. Bonferroni post-hoc tests were used to account for multiple comparisons. Differences in time loss and medical attention injuries were determined using a two-tailed Z test for a comparison of rates. Results:Relative to baseline, EH-S (HG 4.3 kg, 95% CI 3 to 5.7, p < 0.001; TG 5.5 kg, 95% CI 4.3 to 6.6, p < 0.001) and CMJ-H (HG 3.5 cm, 95% CI 2.2 to 4.7, p < 0.001; TG 3.2 cm, 95% CI 2.2 to 4.3, p < 0.001) increased, with no difference between groups observed at the end of the season. All injury outcomes were similar. Conclusion: Rescheduling Part 2 did not affect performance or increased injury risks in academy footballers.

Strength development and non-contact lower limb injury in academy footballers across age groups.

Non-contact lower limb injuries are common in academy football. Yet, the impact these injuries have on strength development in academy footballers remains unclear. This study aimed to investigate the impact of non-contact lower limb injury on hip, groin, and knee flexor strength development in male academy youth footballers. Furthermore, this study: reports normative strength data of emerging field-based tests that can be easily deployed in football academies; explores the effect of age on injury occurrence; and highlights the number of days lost from injury in male youth footballers. Assessments of hip adductor, abductor, and eccentric knee flexor strength were obtained from 195 academy football players during pre-season and at the end of season. In-season injuries were recorded by medical staff. Those footballers who sustained non-contact lower limb injury were compared with those who did not sustain a non-contact lower limb injury. No between-group differences were observed for any strength assessments when controlled for pre-season measures. Stronger footballers at pre-season experienced strength loses, while those weaker players gained strength across the season. Hip strength development was impaired in older age group footballers. Sustaining a non-contact lower limb injury had minimal impact on strength development. In the absence of in-season lower limb strength monitoring, development in academy youth footballers may not progress as expected, and in particular, stronger and older youth athletes may benefit from individualized strength training.

Adolescent football players’ sleep, wellness and school physical activity over different phases of the year

This study aimed to examine differences in sleep and perceived wellness between a group of adolescent academy football (soccer) players from sport high schools (SHS) and regular high schools (RHS) during different phases of the year, with a secondary focus on their school physical activity (s-PA) levels. Data were collected from 51 adolescent football players from one youth Australian academy in two blocks of two weeks (four weeks total). Subjective sleep quantity and quality, wellness and s-PA were assessed through validated daily questionnaires and weekly surveys. MANOVAs and ANOVAs for repeated measures were conducted to assess sleep and wellness variables across different weeks (school vs. holidays, early vs. late season) and between groups (SHS vs. RHS). No differences in sleep or muscle pain were found between players at SHS and RHS (p &gt; 0.05). No effect of week (school vs. holidays, early season vs. late season) on sleep quality or wellness was found, nor did hours of s-PA affect sleep duration (all p &gt; 0.05). Total sleep time was within recommended guidelines and significantly longer sleep times were experienced during the holidays compared to school term (p = 0.002). Overall, adolescent academy football players reported sleep quantities within recommended ranges and had greater sleep volumes during the holidays rather than during school. School type (SHS vs. RHS) and hours of s-PA had no effect on the players sleep within our cohort. Additionally, it appears perceptual wellness in this population is unaffected by time of season, or school compared to holidays.

A multidisciplinary investigation into “playing-up” in academy football according to age phase

ABSTRACT In an attempt to facilitate more appropriate levels of challenge, a common practice in academy football is to play-up talented youth players with chronologically older peers. However, the context of playing-up in academy football is yet to be empirically explored. Thus, the purpose of this study was to examine the multidimensional factors that differentiated players who play-up from those who do not. Ninety-eight participants from a single football academy were examined within their age phase: Foundation Development Phase (FDP; under-9 to under-11; n = 40) and Youth Development Phase (YDP; under-12 to under-16; n = 58). Drawing upon the FA Four Corner Model, 27 factors relating to Technical/Tactical, Physical, Psychological, and Social development were assessed. Following MANOVA analysis within both the FDP and YDP, significant differences were observed for Technical/Tactical and Social sub-components (P < 0.05). Further differences were observed for Physical and Psychological sub-components (P < 0.05) within the YDP. In sum, Technical/Tactical and Social characteristics appeared to differentiate those who play-up compared to those who do not within the FDP. In the YDP however, there were measures representing all sub-components from the FA Four Corner Model. Subsequently, it is suggested coaches and practitioners consider these holistic factors when playing-up youth football players within relevant age-phases.

The youth football journey: parents’ experiences and recommendations for support

ABSTRACT The purpose of this study was to understand parents’ experiences and offer recommendations for supporting parents within youth academy football. The lead researcher was embedded within a football academy for 8 months and collected data through 29 formal interviews, three focus groups, observations, informal conversations, and field notes. Data were analysed using reflexive thematic analysis. Overall, analysis of the data indicated that, while their son was in the academy, parents experience a journey that consists of four individual phases; 1) excited and amazed, 2) dawning of reality, 3) accepting and rationalising, and 4) focusing on the future. Two overarching themes were also present throughout the journey; 1) enjoyment, opportunity, and development, and, 2) sacrifices, commitment, and consequences on personal life. To support parents through these phases, informational and social support, along with cultural changes would be useful. Specifically, parents may benefit from a parent supportive culture in which they are welcomed, respected, and valued, combined with a programme of specific support sessions. Overall, the findings illustrate the complexity of the football academy parent journey and the importance of those providing support to understand parents’ journeys and tailor support to their specific needs.

The Influence of Recruitment Age and Anthropometric and Physical Characteristics on the Development Pathway of English Academy Football Players.

To investigate the influence of recruitment age on retention and release across the development pathway and to explore the influence of anthropometric and physical characteristics on retention and release at different ages throughout the development pathway and the likelihood of obtaining a professional contract. Following receipt of ethics approval, a cross-sectional study tracking 4 cohorts of players over 5 years assessed 76 male youth football players (11-16y) from an English football academy on 3 occasions annually in anthropometry, countermovement jump height, and linear (30 and 15m) and multidirectional sprint time. Players were categorized based on their start and release date. Starting early (ie,before U12) in an academy was a key indicator of obtaining a professional contract, representing 87% of the players signed. Bayesian regression models suggest that the majority of differences in physical characteristics between players that were released and retained are trivial, small, and/or uncertain. Players who attained a professional contract at 18 had slower 15- and 30-m sprint times at U13 to U15 (P > 0 = .87-.99), slower multidirectional sprint times at U14 (P > 0 = .99), and lower countermovement jump height at U13 to U16 (P > 0 = .88-.99) compared with players who did not gain a contract. Players recruited early have an increased likelihood of gaining a professional contract. Physical assessments lack utility when used in isolation as a talent-identification tool.

An investigation into the factors affecting player development within each phase of the academy pathway in english football academies

ABSTRACT The purpose of this research project is to build upon the limited base of academic research into the development of players through the academy pathway in English Football Academies. The unique focus of this study is to investigate the limited academic area of player development specific to each phase of the academy pathway; Foundation Phase, Youth Development Phase and Professional Development Phase. The research was conducted utilizing a questionnaire obtaining quantitative and supplementary qualitative data, designed to target aspects unique to academy environments highlighted by prior academic literature. The results present new evidence that academy football can force unnecessary stress upon players within the foundation, youth development and professional development phases, both internally through pressure to succeed and externally from parents and support networks. The research also confirms that coaching is the strongest influence upon player development, however raises new questions regarding its effectiveness across all phases within academy football.

The Flourishing Footballers programme: Using psycho-education to develop resilience through ACT

This paper details the Flourishing Footballers programme, a practical innovation which was designed to enhance resilience by explicitly integrating ACT into a male Academy football context (Youth Development Phase). The intervention was carried out by implementing a season-long psycho-education programme, which is the culmination of ten years work. Core components of the programme are presented and evaluated. The programme was deemed to be successful based on player engagement with the programme, and utilisation of the taught ACT-based skills. Thus, support is offered for ACT as an efficacious method of intervention within an elite sport context. Consideration is given to the practical implications of this novel programme.

Influence of Training Schedules on Objective Measures of Sleep in Adolescent Academy Football Players.

Brown, GA, Veith, S, Sampson, JA, Whalan, M, and Fullagar, HHK. Influence of training schedules on objective measures of sleep in adolescent academy football players. J Strength Cond Res 34(9): 2515-2521, 2020-Football academy settings may pose risks to adolescent athletes achieving sufficient sleep because of the contextual challenges these players face (e.g., psychosocial pressure, changes in training, competition, and academic stress). Given the importance of sleep to overall health as well as physical athletic development and injury risk, this study aimed to investigate whether differences in training schedules (morning vs. evening training sessions) affected objective measures of sleep in adolescent academy football (soccer) players. Twelve academy players (mean age 14.18 ± 1.36 years) wore an ActiGraph accelerometer on nights before, and nights of, training days in 2 separate weeks where morning (09:00-11:00 hours) and evening (18:00-20:00 hours) training occurred. Objective sleep parameters and training load data were collected. Night-time sleep periods were categorized as sleep preceding morning training, preceding evening training, or after evening training. One-way univariate and multivariate analyses of variance for repeated measures were performed to determine the impact of the training schedule on sleep. Significance levels were set at p < 0.05. The total sleep time was below the recommended guidelines (<8 hours) across conditions. A large significant effect of the training schedule on time attempted to fall asleep (p = 0.004, effect size [ES] = 0.40) and time of sleep (p = 0.003, ES = 0.41) was present, with post-evening sessions resulting in the latest times. Overall, the players' sleep behavior was resilient to changes in training schedules. However, the low sleep durations (and potential risks to physical performance/injury) suggest that sleep education coupled with practical interventions are required in this cohort.

The relationship between eccentric hamstring strength and dynamic stability in elite academy footballers

ABSTRACT Objectives Previous research describes dynamic stability and functional strength as key aetiological risk factors associated with lower limb non-contact musculoskeletal injury. Due to the multifactorial nature of injury risk, relationships between the two factors will inform injury management and training design. Methods A total of 59 elite academy footballers from two English premier league category 1-status academies completed the study. All players completed measures of eccentric hamstring strength and dynamic stability. Relationships between directional stability (Anteroposterior (Ant), Posteromedial (PM) and Posterolateral (PL)) and eccentric strength metrics (PkT, AvT, PkF, AvF and Ɵ) bilaterally were identified for analysis. Results Significant correlations were identified bilaterally for functional hamstring strength metrics and PM and PL stability (P ≤. 0.05). No significant relationships were identified between anterior stability and eccentric hamstring strength parameters (P > 0.05). Conclusions Eccentric hamstring strength has a positive influence on directional stability through two planes, PM and PL. The lack of influence of eccentric hamstring strength on Ant directional stability could be attributed to increased ACL risk. Careful consideration of the significance of the relationships between eccentric hamstring strength and directional stability must be given when quantifying injury risk in elite academy footballers.

Everything matters: The importance of shared understanding to holistically support the psycho-social needs of academy footballers

Elite youth sport environments present unique psychological and social challenges as well as physical challenges to young athletes. In recent years there has been a growing interest in the impact of the psychological and social context across sport including elite football development. However, relatively little has been shared about how these ideas can be put into practice in real world football academies. This paper aims to illustrate concepts and values that underpin the psychological and social environment in a premier league football academy. It describes the work of the academies ‘psych-social team’ (PST), who work with, and within, the wider academy. The aims of the PST are to integrate these ideas across the whole multidisciplinary team (MDT) to create an environment that is both safe and psychologically informed to enhance performance and development of young players. By sharing this developing model, we hope to spark discussion, and collaboration across football about how best to create practical and operational solutions to holistic psychological and social development.

Expertise differences in a 2D animation simulation decision-making task: The influence of presentation speed on performance.

This article investigates the effect of using different playing speeds of 2D animation on the decision accuracy and reaction times of elite footballers. Groups of players from different age categories (under 16, under 18 and under 23 year olds) elite academy footballers watched 2D animations at five different ratios of real-life speed (0.5, 0.75, 1, 1.25 and 1.5 times real-world speed). Participants responded by choosing, from a number of options, which was the best attacking option in each 2D animation clip. After each clip, players also rated each clip for how "game-like" or realistic the scenario felt. Results showed a significant difference between all groups, whereby participants became faster and more accurate by age. Also, the result of "game-like" perception probing which compared perception in each group to each speed showed that the under 16 age group had statistically lower perception accuracy compared to the under 18 and under 23 age groups. This highlights that the more expertise a player has the faster information is processed.

Assessing decision making using 2D animations in elite academy footballers.

Having investigated the effects of videos in the preceding chapter, this chapter assesses 2D animation, a form of presentation used in many coaching situations. The aim of this experiment was to investigate decision-making skills in different age groups (Under 16, 18 and 23) of elite academy footballers using a 2D animation simulation task of real game football scenarios. The work also explored the relationship between individual performance on the task and the actual performance on the pitch, as rated by three independent expert football coaches. This allowed us to examine whether this task is useful in predicting real-world decision-making skills. The results suggested that there was a significant difference between age groups on accuracy, by gaining more experience footballers perform better on the task. Also, the results showed a significant difference between all age groups on the response time. The under 23 age group were fastest, then the under 18 age group and finally the under 16 footballers were the slowest on the task. The correlation between performance on the task and the assessments provided by the coaches showed that 2D animation task is a sensitive measure in assessment of decision-making skills of elite academy players.

Assessing decision-making in elite academy footballers using real-world video clips.

The aim of this experiment was to investigate whether there were differences in decision-making skills between different age groups (Under 16, 18 and 23) of elite academy footballers on a video-based task of real-life football scenarios. It also explored the relationship between individual performance on the task and the performance of the footballers on the pitch, as rated by three independent expert football coaches. This allowed us to examine whether this task is useful in predicting real-world decision-making skills. The results show that there was a significant difference in response times between response time was statistically significantly lower in U23 compared to U18 and U16 and there was no statistically significant difference between the U16 and the U18 groups, but no significant difference between age groups on the accuracy of response. The under 23 age group responded significantly quicker when compared to the under 18 and under 16 age group most quickly, then the U18, and finally, U16 footballers were the slowest on the task. In terms of comparing coaches' opinion about the players' decision-making skills and players performance on the task, there was a positive correlation between accuracy on the task and general decision-making skills rated by the coaches, suggesting that coaches have a good insight on what players can actually do as. However, coaches ratings of decision-making skills and response times on the task did not correlate suggesting that coaches are not aware of the speed of decision-making, and that this is only measurable by a representative task.

Labdarúgó akadémisták rekrutációjának és elégedettségének vizsgálata a fővárosi és a vidéki akadémiák tükrében

Az utóbbi időben a honi labdarúgó akadémiákkal kapcsolatos kutatások egyre népszerűbbé válnak, noha maga a magyar labdarúgó akadémiai rendszer immáron közel 18 éves múltra tekint vissza hazánkban. A pedagógiai aspektusokat fókuszba helyező vizsgálatok azonban manapság is kevésbé preferáltak a kutatók részéről, hiszen az akadémistákat egyelőre kevesebb ilyesféle vizsgálat érintette, így a szakirodalom is korlátozott ilyen tekintetben. Jelen kutatásunkban azonban az ezekben az intézményekben fejlődő fiatal növendékek vizsgálata jelenik meg. Célunk konkrétan az volt jelen tanulmány megírásával, hogy terepmunka segítségével az általunk kiválasztott hat akadémiában (Debreceni Labdarúgó Akadémia, Diósgyőri Labdarúgó Akadémia, Békéscsabai Labdarúgó Akadémia, Sándor Károly Labdarúgó Akadémia, Magyar Futball Akadémia, UTE Labdarúgó Akadémia) az ottani akadémisták rekrutációját és elégedettségét vizsgáljuk meg a fővárosi és a vidéki intézmények tükrében.Kutatásunkhoz a kérdőíves lekérdezés módszerét alkalmaztuk, amely segítségével összesen 560 labdarúgó akadémistát sikerült megszólaltatnunk.Az eredményeink alapján több esetben is szignifikáns különbségeket véltünk felfedezni az egyes akadémiák akadémistáinak válaszai között. Az intézmények között szignifikáns különbségek mutatkoztak az akadémisták rekrutációját (p=0,000), a növendékek elégedettségét az egyes intézmények felszereltségét (pályák, öltözők, eszközök) (p=0,000), illetve a saját edzőik szakmai felkészültségét (p=0,004) illetően is. Eredményeink segítségével betekintést tudunk nyerni az egyes honi labdarúgó akadémiai intézmények sajátos világába, ezáltal megismerhetjük az ott fejlődő fiatalok véleményeit az akadémiák ellátottságáról, esetleges hiányosságairól.

Psychological characteristics of developing excellence in elite youth football players in English professional academies

ABSTRACT This mixed-longitudinal prospective study examined the development of psychological characteristics of developing excellence in relation to the career progression of elite youth football players. In a 20-month period, 111 academy football players aged 11–16 completed the Psychological Characteristics of Developing Excellence Questionnaire (PCDEQ) on 1–5 occasions. This combination of single and repeated assessments resulted in a mixed-longitudinal sample of 226 completed PCDEQs. Players were then prospectively tracked, and their scholarship status assessed at follow-up, at age U17. Multilevel modelling revealed that coping with performance and developmental pressures scores increased with age, and that Category 1–2 academy scholars (4.35 ± 0.61) scored higher than Category 3–4 academy scholars (3.99 ± 0.67) and non-scholars (4.02 ± 0.78) (p < .05). Evaluating performances and working on weaknesses scores increased with age for Category 1–2 academy scholars (U12-U14 vs. U15-U16 = 5.16 ± 0.48 vs. 5.38 ± 0.45), compared to non-scholars (U12-U14 vs. U15-U16 = 5.11 ± 0.59 vs. 5.03 ± 0.71) (p < .05). Imagery use during practice and competition scores decreased with age (U12-U14 vs. U15-U16 = 4.45 ± 0.66 vs. 4.29 ± 0.70) (p < .05). A blend of PCDEs may facilitate optimal career progression. Football academies should develop players’ PCDEs, with a particular focus on developing their coping skills and their ability to realistically evaluate performances and work on weaknesses.

A Genome-Wide Association Study of Sprint Performance in Elite Youth Football Players

Pickering, C, Suraci, B, Semenova, EA, Boulygina, EA, Kostryukova, ES, Kulemin, NA, Borisov, OV, Khabibova, SA, Larin, AK, Pavlenko, AV, Lyubaeva, EV, Popov, DV, Lysenko, EA, Vepkhvadze, TF, Lednev, EM, Leońska-Duniec, A, Pająk, B, Chycki, J, Moska, W, Lulińska-Kuklik, E, Dornowski, M, Maszczyk, A, Bradley, B, Kana-ah, A, Cięszczyk, P, Generozov, EV, and Ahmetov, II. A genome-wide association study of sprint performance in elite youth football players. J Strength Cond Res 33(9): 2344-2351, 2019-Sprint speed is an important component of football performance, with teams often placing a high value on sprint and acceleration ability. The aim of this study was to undertake the first genome-wide association study to identify genetic variants associated with sprint test performance in elite youth football players and to further validate the obtained results in additional studies. Using micro-array data (600 K-1.14 M single nucleotide polymorphisms [SNPs]) of 1,206 subjects, we identified 12 SNPs with suggestive significance after passing replication criteria. The polymorphism rs55743914 located in the PTPRK gene was found as the most significant for 5-m sprint test (p = 7.7 × 10). Seven of the discovered SNPs were also associated with sprint test performance in a cohort of 126 Polish women, and 4 were associated with power athlete status in a cohort of 399 elite Russian athletes. Six SNPs were associated with muscle fiber type in a cohort of 96 Russian subjects. We also examined genotype distributions and possible associations for 16 SNPs previously linked with sprint performance. Four SNPs (AGT rs699, HSD17B14 rs7247312, IGF2 rs680, and IL6 rs1800795) were associated with sprint test performance in this cohort. In addition, the G alleles of 2 SNPs in ADRB2 (rs1042713 & rs1042714) were significantly over-represented in these players compared with British and European controls. These results suggest that there is a genetic influence on sprint test performance in footballers, and identifies some of the genetic variants that help explain this influence.

Relative age and maturation selection biases in academy football

ABSTRACT This study examined the simultaneous effects of relative age and biological maturity status upon player selection in an English professional soccer academy. A total of 202 players from the U9 to U16 age groups, over an eight-year period (total of 566 observations), had their relative age (birth quarter) and biological maturity (categorised as late, on-time or early maturing based upon the Khamis-Roche method of percentage of predicted adult height at time of observation) recorded. Players born in the first birth quarter of the year (54.8%) were over-represented across all age groups. A selection bias towards players advanced in maturity status for chronological age emerged in U12 players and increased with age; 0% of players in the U15 and U16 age group were categorised as late maturing. A clear maturity selection bias for early maturing players was, however, only apparent when the least conservative criterion for estimating maturity status was applied (53.8% early and 1.9% late maturing in the U16 age group). Professional football academies need to recognise relative age and maturation as independent constructs that exist and operate independently. Thus, separate strategies should perhaps be designed to address the respective selection biases, to better identify, retain and develop players.