Special topics

The purpose was to evaluate whether a change of head coach or other head staff before or during a season is correlated to hamstring injury (HI) burden in male elite-level football (soccer) in Europe.

The present study aimed to analyse the performance of the Spanish men’s top (LaLiga1) and second (LaLiga2) professional football division teams for eight consecutive seasons (from 2011–2012 to 2018–2019).

The aim was to compared in-game penalty kicks taken by home and away teams with audiences in the 2018-2019 season to kicks taken without audiences in the 2020-2021 season during the COVID-19 pandemic.

The anthropometric profile assessment is an important aspect to consider during the growth stages of youth sport practitioners due to its usefulness in controlling maturity status and overall health.

The aims of the study were to build models using logistic regression analysis of flexibility and strength tests to prospectively predict risk factors for anterior cruciate ligament tear (ACL-tear) in female soccer (FS) players, and to determine training cut-off for risk factors of the predictive model built.

This study aimed to determine differences in match running performance (MRP) of elite soccer players during matches played on artificial turf (AT) and natural grass (NG).

The primary aim was to compare the peak running speed (PRS) attained in the 40-m linear sprint test, in an analytical-based soccer drill, in the 5-0-5 test, and a training match scenario. The secondary aim of the study was to evaluate the differences between the three assessment sessions and identify how the tests can vary from session to session. Additionally, we aimed to investigate the within-test variability to understand how consistent the performance is within each test format across the different sessions.

Muscle typology is heterogeneous among national level soccer players, but positional differences remain unclear. Furthermore, fast typology (FT) individuals fatigue more than slow typology (ST) individuals in lab conditions. Therefore, we investigated if muscle typology is different between playing positions and if the decay in high-intensity activities from the first to the second half is larger in FT football players than in ST players.

The aim of the study is to correlate anthropometric, strength and power variables with the relative age (RA) and the level of the teams in which players played in each age category.

This study aimed to analyze the performance of substitute players and explore the performance difference among substitute players, completed players, and replaced players across each position.

The present study aimed to describe the occurrence of near-to-maximal sprinting speed (near-to-MSS) running bouts during training and hamstring injuries during the consecutive match.

This study compared the effects of two sprint-jump training programmes, performed on either sand or grass surfaces, on the sprint and jump performance of elite young soccer players over an 8-week training period.

This study aimed to analyse the influence of effective playing time on physical match performance according to playing position in professional soccer.

This study aimed to compare the daily training load (TL) in first-team and U-18 soccer players from an English Premiership club.

This study aims to analyse the evolution of match running performance in relation to the age distribution of professional soccer players using a large-scale analysis.

The aims of this study were to compare the influence of transition game (TG) size on the external and internal loads of young professional soccer players and to describe the high-speed profile of these drills.

The study aim was to assess whether match-derived external-to-internal load ratios are a valid and reliable tool to measure physical fitness.

The purpose of this study was to investigate the association between hamstring muscle fibre type, hamstring strain injury history (HSIH), performance and isokinetic strength in a population of amateur male soccer players.

In order to identify match running performance (MRP) characterizing the most elite soccer matchplay, this study aimed to examine position-specific differences in the MRP of players competing in “big five” (BFLTs) and “non-big five” league teams (N-BFLTs).

The purpose was to examine relationships between external loads (ELs), perceived exertion, and soreness.

This study aimed to explore the differences in playing style and technical performance according to the ranking level in Spanish football teams.

The purpose of this study was to analyze the influence of tactical behavior on physical performance of the three best Spanish soccer teams.

This investigation aimed to study the impacts of Verbal encouragement (VE) given by coaches on the physiological aspects, players’ internal intensity, mood, and perceived enjoyment of youth soccer players during repeated agility speed training (RAS).

The aims of the study were to: (i) compare accumulated load and wellness between starters and nonstarters of a European professional soccer team; (ii) analyze the relationships between wellness and load measures and; (iii) compare training/match ratio (TMr) of external and internal load between starters and non-starters.

This study analysed external and internal TL variables and their association with injury incidence in a group of male elite youth football players over four seasons.

The objective of this research was to analyse the most demanding passages (MDP) considering the sprint variable relative to the maximum level of sprint ability of each player as a function of player position, final outcome and part of the match during the competitive phase of a professional soccer season.

The influence of high-intensity actions on match performance outcomes has not been established. The aim of the present study was to identify the influence of high-intensity accelerations (ACC) and decelerations (DEC) on match performance outcomes (i.e., win, draw, lost).

The aim of the study was to compare the status of somatic maturity, anthropometry, strength, speed, and soccer-specific technical skills of players from leading youth soccer academies born in different quarters of the same calendar year.

Therefore, this study aimed to compare the effects of different stretching methods on COD ability in soccer players.

The purpose of the study was to investigate whether a re-warm-up training session either with tuck jumps and linear sprints or with changing of directions (COD) may enhance power, agility or ball shooting velocity.

The interpretation of the load variations across a period seems important to control the weekly progression or variation of the load, or to identify within- micro and mesocycle variations. The aim of this study was to describe the in-season variations of training monotony, training strain, and acute:chronic workload ratio (ACWR) through session rating of perceived exertion (s-RPE), total distance (TD) and high-speed running (HSR) according to playing positions in an elite soccer team.

Outscoring opponents is the primary goal in football. To optimise goal scoring opportunities (GSOs), it is important to understand the preceding physical and tactical performance. This observational study explored whether running behaviour prior to GSOs related to the subsequent outcome or contextual factors.

With the recent development in playing time I thought it would be interesting to see the average duration of matches during the current or last completed season. 52,4% of matches are over 100 minutes. 

This study aimed to compare the significant turning demands of English Premier League soccer match play relative to playing position using LiDAR technology.

This study aims to provide information to improve the performance of athletes comparing the effects of carbohydrate–electrolyte intake before and during exercise on metabolism and performance in soccer players.

The aim of this study was to explore the changes in physical performance by playing position throughout professional soccer match-play.

The This study aimed to evaluate the relationship between physical demands, skin temperature, and well‐being status in 30 Spanish professional football players over a 12‐week competitive period. 

Effective playing time has been debated as a topic of major concern in football. Thus, the current experimental study aimed to investigate the effects of effective playing time on technical-tactical and physical match parameters in football.

The aim of this study was to compare the effects of autoregulating strength training volume based on an objective (external load match performance) vs. a subjective (self-selected) method in professional footballers.

The effects of strength training on muscle strength imbalance are unclear in professional soccer players. As a result, this study examined the effects of an 8-week strength training program comprising eccentric emphasized prone leg curl adjusted according to the individual strength imbalance status.

This study aimed to evaluate external load based on distance and accelerometry measures in six different microcycle schedules with congested (CW2, CW3, and CW4) and regular weeks (RW4, RW5, and RW6) in professional soccer players.

The purpose was to compare the locomotor demands of several ball/running drills with the official match peak, demands determined across different time-windows of the same duration in top-class male soccer players.

The aim of this study was to examine the effects of a 4-week detraining period on the neuromuscular performance of highly trained soccer players.

This study aimed to compare the effects of in-season sprint training vs. Nordic hamstring exercise (NHE) training on risk factors for hamstring strain injuries (HSI).

This study aimed to analyze the locomotion activity of elite-level soccer players throughout the weekly microcycle by playing position, and compare the training-load (TL) behavior in relation tomatch-play in absolute and relative (meters or events per minute) terms.

This study aims to propose a three-level model of factors contributing to YYIR2 performance, based on the investigation of relationships with aerobic endurance, repeated sprint ability (RSA), and the linear and change-of-direction (COD) variables.

The purpose was to examine the association between the programming of days off (ie, no pitch training, days off feet) within turnarounds of varying length and injury rate in elite soccer.

This study aimed to compare the running demands of professional youth soccer players in congested periods according to their specific playing positions.

Relative Age Effects (RAEs) appear largely throughout youth soccer. However, little is known about how RAEs at youth levels can impact transition at senior levels.

The purpose of this study was to investigate the feasibility and short-term effects of a novel position-specific conditioning training (PSCT) paradigm on physical and technical abilities of young soccer players.

This study aimed to examine the effects of substitute player allowance per match on running performance in Japanese professional football over three consecutive seasons with different numbers of maximum substitutes.

We examined the influence of accumulated match-play exposure on the occurrence of hamstring strain injury in professional football from 2 teams (Spanish 1st Division, LaLiga) over 3 seasons, and determined specific cut-off points as indicators of injury risk. 

This study aimed to investigate the effect of offensive playing style (i.e., while in ball possession) on physical and technical match performance during offensive play as well as success-related factors.

The aim of this study was to assess how the teams’ match running performance indicators are related to low ambient temperature during competitive matches in the Russian Premier League.

The present study aimed to investigate the area per player (ApP) to replicate the technical and locomotor match demands using small-sided games (SSGs) in male footballers competing in European and UEFA competitions.

The training load is associated with injury risk in a variety of sports. This study aimed to evaluate the association between the internal training load and injury risk in Brazilian professional soccer players.

This study investigated the extent to which biological maturation selection biases existed according to playing position in national-level youth soccer.

This study aimed to investigate the effect of a combined jump and sprint training program, two sessions a week for 6 weeks, on sprinting, change of directions (COD) and jumping performance in semi-professional footballers.

In elite-level youth soccer players, weekly training periodization is of paramount importance to plan for short- and long-term physical development. The present study investigated current practices for physical periodization strategies in elite male French academies.

This study aimed to compare the effects of horizontal (HJ) and vertical (VJ)‐based plyometric jump training on male semi‐professional soccer player’s performance.

We examine the differences in running performance demands and tactical individual actions for male amateur football wingers in four tactical formations: 4-2-3-1, 4-4-2, 3-5-2 and 3-4-2-1 during an entire season.

This study aims to: a) investigate the training situation of players in the Chinese School Football Programme and b) examine the associations of early specialization, sports volume, and maturity status with injury.

The aims of this study were to investigate the periods in which sprints occurred during official matches and analyze these sprints considering the effect of the playing position and different contextual variables.

The purpose of this study was to verify whether decision-making skills influence the tactical behaviour and physical performance of soccer players under acute physical fatigue, assessed in an actual game-play.

The aims of this study were to investigate the periods in which sprints occurred during official matches andvanalyze these sprints considering the effect of the playing position and different contextual variables.

The purpose of this research was to investigate the running performance of professional soccer players in relation to seven phases which resulted in the changing or maintaining the match status in the UEFA Champion League games during season 2020/2021.

The objective of this research was to analyse the most demanding passages (MDP) considering the sprint variable relative to the maximum level of sprint ability of each player as a function of player position, final outcome and part of the match during the competitive phase of a professional soccer season.

The purpose of this study was to examine the differences in the trunk and lower extremity biomechanics associated with anterior cruciate ligament (ACL) injury risk factors between a standard DVJ and a DVJ while heading a soccer ball (header DVJ.

This study aimed to examine the independent effect of different match-related factors on match

running performance (MRP) in elite soccer.

The aim of this study was to analyze the association between teams’ success at the end of the season and match running, and technical-tactical performance in two professional soccer leagues.

The purpose of this study was to analyze the relationship between sprint performance (time), and strength and power capabilities in football players.

This study aimed to analyse physical performance relative to peak locomotor demands of match play.

The present study compared the effects of two different small-sided game (SSG) training methods, interval (ISSG) and continuous (CSSG) on the bio-motor abilities of young soccer players.

This case describes a professional soccer player returning to match play (English CL) following a medial meniscectomy that occurred during the rehabilitation after Anterior Cruciate Ligament (ACL) reconstruction.

Non-starters soccer players have a great role within the team, being indispensable to reduce fatigue, as

well as to maintain and increase the team’s performance during the match. This study analyzed the physical performance of the starters (STA) and non-starters players (NOP) during competitive soccer matches.

The aim of this study was to investigate the external load (EL) indicators differences in players of different playing positions (central backs CB, external strikers ES, fullbacks FB, midfielders MF, strikers ST, wide midfielder WM) between and within different sport-specific tasks and official matches.

This study aimed to evaluate the impact on physical demands induced by FIFA’s new rule implemented based on the number of substitutions caused by COVID-19.

The aims of this study were to (i) analyze the physical and physiological responses of four matches competition and (ii) to investigate the relationships among three different pitch dimensions of small-sided game (SSG) on the youth soccer players.

This study aimed to explore the relevance of the relative age effect (RAE), maturity status and anthropometry, and their influence on coaches’ assessment of players’ performance, analyzing both genders and different types of academies (elite vs. non-elite only male displayed).

The purpose of this study was to evaluate the relationships between objective fatigue variables (Squat Jump (SJ) and Countermovement Jump (CMJ)) measured on day-2 to the game and subjective fatigue (Rating Perceived Exertion (RPE) measured on day-3 to the game and Hooper Index (HI) measured on day-2).

The aim was to compare the biceps femoris long head (BFlh) architecture between football players with (twelve) and without (twenty) history of BFlh injury before and after a repeated sprint task. 

This prospective study aimed to examine in detail the effects of sports injuries on professional football players’ weekly external load performances.

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.

The present study examined the effects of stressful constraints during soccer trainings on psychological skill development and internal load when compared with control (non-stressful) trainings.

This study examined the effects of a six-week preparatory training program on physical performance and physiological adaptations in junior soccer players. Additionally, we investigated whether a relationship existed between external and internal loads.

The aim of this study was to compare the effects of small-sided soccer games (SSSGs) and traditional warm-up (TWU) routines on physical fitness qualities in soccer players.

The present study aimed to contextualise physical metrics with tactical actions according to general and specialised tactical roles.

Temporal changes in the total running demands of professional football competition have been well documented, with absolute running demands decreasing in the second half. However, it is unclear whether the peak match running demands demonstrate a similar decline.

The aim was to compare the effects of playing one or two games per week on subjective perceived exertion (RPE) and (RPE-based) training load, monotony index, sleep, stress, fatigue, and muscle soreness (Hooper index), total mood disturbance, and injury rate in elite soccer players.

This study aimed to investigate the effects of contextual match factors (quality of opposition, match outcome, change of head coach or playing style) on internal and external load in elite Brazilian professional soccer players, considering the total and effective playing time.

The objective of the present study was to assess the workload of soccer-specific drills in professional players over a two-season period in an established context.

The objective of the present study was to assess the workload of soccer-specific drills in professional players over a two-season period in an established context.

The aim of this study was to quantify and tactically contextualise (i.e., phase of play and tactical outcome [TO]) sprints (≥7.0 m/s) of an English Premier League (EPL) soccer team during match-play.

The study investigated the relationship between short sprint performance and mechanical parameters obtained during the acceleration and deceleration tasks with the change of direction (COD) performance in female and male soccer players.

The International Match Calendar congestion affects players recovery. The views of a worldwide cohort of professional football players is shared in this communication.

This study tested the effects of two training programs (1v1 vs. 5v5) on the physical fitness adaptations of youth soccer players. In specific, it was analyzed the effects of the training programs on the 5–0–5 change-of-direction time (5–0–5 time), countermovement jump (CMJ), and final velocity in the 30–15 Intermittent Fitness test (VIFT).

The aim of this paper was to explore the effects of age and playing tactics on the individual tactical behavior and performance in young soccer players.

The purpose of this study was (i) to compare two groups (players with more vs. less match play time) regarding body composition, vertical and horizontal jumping performance, and aerobic capacity; and (ii) to test the relationships between physical fitness and play time.

The present study aimed to determine the physical impact of different training durations on MD-1 on the subsequent matchday performance (MD).

The purpose of this study was to examine differences in the genotype frequency distribution of thirty-three single nucleotide variants (SNVs) between youth development phase (YDP) and professional development phase (PDP) academy football players.