Elite Football Players Research Articles

Mechanisms explaining the birthplace effect for male elite football players

ABSTRACT Earlier research shows that wide regional variations exist in the success of athletes’ talent development but is divided with respect to the role of urbanity: both low and high urbanity have been identified as settings that contribute to the presence of talent hotspots. In this article, we intend to provide more insight into the role of urbanity in talent development in Dutch football. We used public data on the regional background of male elite players (N = 825) and combined this with public data on municipal characteristics from Statistics Netherlands and other sources: urbanity, football participation, instructional resources and population composition effects (migration background and income of inhabitants). Linear regression analysis showed that football participation, the proportion of non-western migrants and median income predict “talent yield”, i.e., the proportion of young people that reach an elite level in a municipality. Urbanity does not have an independent influence when the proportion of non-western migrants in the municipality is taken into account. The presence of instructional resources does not have an independent influence. The results suggest that characteristics of the built environment, such as indoor and outdoor play opportunities, may be less influential in talent development than previously assumed.

The sensitivity of countermovement jump, creatine kinase and urine osmolality to 90-min of competitive match-play in elite English Championship football players 48-h post-match

ABSTRACT Purpose: Examine changes from 90-minutes of competitive match-play in countermovement jump (CMJ), creatine kinase (CK) and urine osmolality (Uosm) in elite football players over a season and their association to match external load. Methods: Eighteen footballers participated. CMJ, CK and Uosm were collected 24-h pre-match and 48-h post-match. Match-performance data was examined using Prozone®. Results: Post-match CK concentrations increased 49% (ES:0.66), while CMJ flight-time (FT), flight-time:contraction time ratio (FT:CT), take-off velocity (TV) and average power (AP) decreased 2.4-7.4% post-match (ES:0.39-0.63). CMJ height post-match reduced 4.2% (ES:0.35). CMJ FT and AP showed associations with high intensity distance covered (HID), high intensity number (HIN), explosive sprints (EXS) and medium intensity accelerations (r= -0.395 to -0.496). Changes in CMJ FT also displayed associations to total sprint distance (TSD), total sprint number (TSN) and medium intensity decelerations (r = -0.395-0.446). Increases in CMJ CT were associated with HIN (r=0.39), and CMJ AF with HIN, EXS and medium accelations/decelerations (r= -0.397 to 0.459) completed during the match. Conclusion: CMJ outputs from the push-off phase and countermovement phase were sensitive to change in neuromuscular fatigue. CK concentrations were sensitive to the match-play demands. This helps practitioners determine player readiness and has implications for individual recovery strategies.

Scanning, Contextual Factors, and Association With Performance in English Premier League Footballers: An Investigation Across a Season.

Scanning in football (soccer) denotes an active head movement where a player’s face is temporarily directed away from the ball to gather information in preparation for subsequently engaging with the ball. The aim of this study was to learn more about the ways that 27 elite professional football players in an English Premier League club use scanning in competitive matches, the conditions under which this behavior is exhibited, and the relationships between these behaviors and performance. Players were filmed across 21 matches, producing a total number of 9,574 individual ball possessions for analysis. Close-up video analyses of scanning show positional differences (with central midfielders and central defenders scanning most frequently, forwards least) and contextual differences (with relatively lower scanning frequency in situations with tight opponent pressure, in positions wide in the field and closer to the opponent’s goal, and under certain game state conditions). Players scan more frequently prior to giving passes than when they dribble, shoot, or only receive it, as well as prior to more long/forward passes compared to short/backward ones, although these differences are small. A Bayesian hierarchical model, which accounts for individual player differences and pass difficulty, suggests that the more a player scans, the higher the probability of completing a pass. In conclusion, match demands are likely to constrain the extent to which highly elite players scan, and scanning seems to have a small, but positive role in elite football players’ performance.

Deconstructing celebratory acts following goal scoring among elite professional football players.

Goal celebration in sport is mostly spontaneous and is manifested via vocal expressions and bodily gestures aimed at communicating emotions. The aim of this study is to deconstruct the celebratory acts among elite professional football players in the European Champions League following scoring a goal, and to capture the multiple acts and functions of the celebrations. In examining the 2018/19 season of the European Champions League tournament, we draw attention to the players' celebrations and their corresponding social and individual functions. All goals/celebrations (K = 366) were used for the analyses. To analyze the goal celebration acts, a socio-psychological model was established which is comprised of several theories. To describe the goal celebration acts across the competition stages (e.g., preliminary and final), match location (i.e., home or away), time phase (0-15, 15-45, 45-75, 75-90, 90+ minutes), scoring mode (i.e., prior to the goal, after the goal), and players' continent origin (Europe, Africa, Asia, South/Central, and North America), the number and percent of all the celebratory acts were counted and presented in their respective mode (i.e., single, double, and team). The main findings indicate that (a) most of the goal celebration acts were performed interactively by the scoring player and his teammates, (b) the interactive modes of celebration lasted longer than the modes which were performed non-interactively, (c) the celebration lasted longer following goal scoring in the final stage than in the preliminary stage, (d) the celebration duration lasted the longest time when the goal was scored during the overtime phase (90+ min) of the final but not the preliminary stage, and (e) players from Africa and South America demonstrated religious acts more than their European counterparts. We assert that our conceptual model enables the categorization of a variety of personal and social meanings to the celebrations on the field during the most thrilling moments of the game.

Does the choice of syndesmotic screw versus suture button in ankle surgery has a silver lining? \u2013 a technical note

PurposeUnstable ankle fractures with associated syndesmotic injury are of considerable morbidity in the professional athlete population. The use of dynamic suture button versus static syndesmotic screws fixation, rehabilitation protocols and timing to return to play are still areas of debate. We report the use of novel algorithm of sequential static and dynamic syndesmotic fixation in an elite football player with Weber C ankle fracture.MethodsThe patient underwent open reduction and internal fixation for a weber C ankle fracture with associated syndesmotic and deltoid ligament injury. The osteosynthesis included lateral malleolus neutralizing plate, two syndesmotic screws and deltoid anchor repair. At 6 weeks post-operative both syndesmotic screws were removed and one suture button was implanted in the proximal screw hole. After the second operation the patient was allowed full weight bearing and range of motion in all direction with accelerated rehabilitation protocol.ResultsThe technique provided satisfactory results. At 4 month the player participated in a 90 min official football match. The fracture healed uneventfully with no recurrent syndesmotic diastasis.ConclusionThe presented technique of sequential dynamic and static fixation of associated syndesmotic injuries combined advantages of both syndesmotic screws and suture button implants. In an aim to allow earlier return to play in an elite football player. This opens the way for higher level of evidence clinical trials.

Development of an on-field injury screening test using wearable sensor technology

Introduction:Injuries of the anterior cruciate ligament (ACL) commonly occur during complex game situations when the athlete encounters multiple factors such as ball, opponent, field position, and game strategy (Grooms et al., 2018). Many of the current traditional injury screening programs are performed within a predictable, fixed or ‘closed’ environment which do not represent real game situations that require high neurocognitive demands (Dingenen & Gokeler, 2017; Grooms et al., 2018). A complementary approach to lab-based settings is necessary to incorporate the demands of the complex athletic environments. By using wearable sensor technology, we aim to develop an on-field injury screening test in elite youth male soccer players. Investigating the individual differences in motor coordination patterns of the players during sport-specific tasks might enhance our understanding of how ACL injuries occur.Hypotheses:We hypothesized that the motor coordination patterns of the players would be affected when they perform under different conditions manipulated with constraints (task and environmental).Methods:A football-specific test setup was created to analyse the kinematic and performance measures of a group of 17 male youth elite football players aged 15 years (height = 164 ± 9 cm, mass = 50.9± 7.4 kg). The players were grouped into two and measured on two consecutive days. All the players were instructed to complete the test setup (4 conditions, 5 trials) as fast as possible. Condition 1 includes no constraint, condition 2 includes a task constraint (football dummies), condition 3 includes an environmental constraint (stroboscopic glasses) (SENAPTEC, Beaverton, Oregon) and condition 4 includes both task and environmental constraints. 3-D kinematics of the hip, knee, ankle joints were captured using Xsens wearable full-body sensor suits (Xsens, MVN Link version, Enschede, The Netherlands). MATLAB (MATLAB R2019a, The MathWorks Inc., Massachusetts) was used to process and analyse the kinematic data. Data from condition 1 was determined as reference behavior/condition to be compared to other conditions. Kinematic data are presented in attitude vectors (ATV).Results:In total, 81% of the players demonstrated a significant difference (P < 0.05) in angles of hip, knee and ankle joints when performing under different conditions. The percentage of players with increased comparison-based joint movements as follows; condition 1 to condition 2 comparison; 41% hip flexion, 59% hip extension, 53% hip abduction, 47% hip adduction, 62% knee flexion, 38% knee extension, 59% knee abduction, 41% knee adduction, 47% ankle dorsiflexion, 53% ankle plantarflexion, condition 1 to condition 3 comparison; 35% hip flexion, 65% hip extension, 47% hip abduction, 53% hip adduction, 50% knee flexion, 50% knee extension, 41% knee abduction, 59% knee adduction, 59% ankle dorsiflexion, 41% ankle plantarflexion and condition 1 to condition 4 comparison; 31% hip flexion, 69% hip extension, 38% hip abduction, 62% hip adduction, 60% knee flexion, 40% knee extension, 44% knee abduction, 56% knee adduction, 69% ankle dorsiflexion, 31% ankle plantarflexion.Conclusion:The result of this pilot study demonstrated that manipulating task with different constraints caused significant changes in players’ motor coordination patterns which supported the hypothesis of our study. Our findings suggest to develop ACL injury screening tests in a sport-specific setting.

Effect of the Fatigue on the Physical Performance in Different Small-Sided Games in Elite Football Players

Calderón Pellegrino, G, Paredes-Hernández, V, Sánchez-Sánchez, J, García-Unanue, J, and Gallardo, L. Effect of the fatigue on the physical performance in different small-sided games in elite football players. J Strength Cond Res 34(8): 2338-2346, 2020-Football players need to be able to perform high-intensity efforts of short duration with brief recovery periods. The aim of this study was to analyze the influence of the pitch dimension on high-intensity actions and the effect of a repeated sprint ability (RSA) test on the physical performance in different 4-against-4 (4v4) small-sided games (SSG) dimensions. Sixteen U-18 elite football players performed an RSA test between two 4v4 SSGs (pre and post) to induce fatigue and compare physical data. Speed, sprint number, accelerations, sprint distance, total distance covered, and total distance covered of the players at different intensities were evaluated in 3 different SSGs (125, 150, 250, and 300 m). Results revealed a significant detriment of physical performance in the 125-m SSG after RSA, mostly in number of sprints (-6.56; confidence interval [CI] 95%: -10.13 to -3.00; effect size [ES]: 1.13 p < 0.001), accelerations (-2.69; CI 95%: -5.13 to -0.24; ES: 0.68; p = 0.032), and sprint distance (-65.44 m; CI 95%: -103.73 to -27.16; ES: 1.20; p = 0.001). In bigger SSGs (250 and 300 m), higher distance at high intensity was covered and Vmax, Vmean, and sprint distance were greater. In summary, accelerations, sprint number, and fatigue were higher in smaller pitches, and higher velocities were reached in bigger SSGs. Football players should be aware that changes in pitch size can modify the physical performance on high-intensity actions in SSGs.

Association between the ACE I/D polymorphism and muscle injuries in Italian and Japanese elite football players

ABSTRACT ACE I/D polymorphism has been recently associated with the susceptibility to inflammation and muscle damage after exercise. The aim of this study was to understand the association between the ACE I/D polymorphism and muscle injuries in a large cohort of elite football players from two different countries. Seven hundred and ten male elite football players from Italy (n = 341) and Japan (n = 369) were recruited for the study. Genomic DNA was extracted from either the buccal epithelium or saliva using a standard protocol. Structural-mechanical injuries and functional muscle disorders were recorded from 2009 to 2018. A meta-analysis was performed using Review Manager 5.3.5. In the Japanese cohort, the ACE I/D polymorphism was significantly associated with muscle injury using the D-dominant model (OR: 0.48, 95% CI: 0.24–0.97, P = 0.040). The meta-analysis showed that in the pooled model (Italian and Japanese populations), the frequencies of the DD+ID genotypes were significantly lower in the injured groups than in non-injured groups (OR: 0.61, 95% CI: 0.38–0.98, P = 0.04) with a low degree of heterogeneity (I2 = 0%). Our findings suggest that the ACE I/D polymorphism could influence the susceptibility to developing muscle injuries among football players.

Injuries and functional performance status in young elite football players: a prospective 2-year monitoring.

Motor function, such as strength asymmetries of the lower extremities and impaired dynamic stability, have a predictive value for the risk of injury. The present study aimed to reveal potential associations between injury and motor performance. Two hundred and five male youth elite (association) football (soccer) players (mean: 13.5±4.5 years, 57.2±30.2 kg, 168±35 cm) were included. A test battery was conducted twice per season, over two consecutive seasons (four times). Mobility (Sit and Reach Test, SnR), dynamic stability (Single Leg Hop for Distance, SLHD), linear sprinting speed (10 m, 30 m [s]), agility (Zig-Zag test with and without dribbling a ball [s]), jump performance (countermovement jump (CMJ) and drop jump (DJ), in cm) and maximal isometric voluntary force (MIVF, in N) of the knee extensors and flexors were assessed. All injuries occurring over the two-year period, as well as training and competition exposure time, were collected and used as grouping variables for statistical difference testing. One hundred and twenty-five injuries in 93 players occurred (an injury incidence of 2.7/1000 hours of exposure). Age was associated with injury incidence (r=0.191; P=0.006). Neither DJ, CMJ, SnR nor agility performance were statistically different between injured and non-injured participants (P>0.05). Group differences did occur for sprint and strength (P=0.011; P=0.016), but these lapsed after the inclusion of age as a covariate. Only for SLHD symmetry was a non-significant trend evident after the correction for age (P=0.08). The occurrence of musculoskeletal injuries in junior football players are, probably, not related to baseline motor function. Group differences between injured and non-injured youth elite football players are mostly explained by age. Only the symmetry in SLHD could be a potential risk factor for injuries and merits further investigation.

Risk Factors Influencing the Incidence of Ankle Sprain Among Elite Football and Basketball Players: A Prospective Study.

Introduction. The objective of the present study was to investigate whether certain intrinsic factors (foot hyperpronation, generalized joint laxity) and clinical tests (anterior drawer and talar tilt tests, single-leg balance test and star excursion balance test, ankle and first metatarsophalangeal range of motion) could predict the incidence of lateral ankle sprains among elite football and basketball players during a full year. Method. In a prospective cohort study, 106 elite basketball and football players were recruited. During the preseason period, players underwent baseline measurements. Team physicians in following year reported occurrence of new ankle sprains. Results. Ankle sprain was more frequent among basketball players (P = .01). The history of recurrent (P = .001) and acute ankle sprain (P = .01) and each 5-year increase in age (P = .039) were predictive factors for ankle sprain. No evidence for relationship between other risk factors and occurrence of ankle sprain were achieved. Conclusion. In our study, the history of recurrent and acute ankle sprain was the strongest predictor for ankle injuries. Considering the limitations of this study, it seems mandatory to conduct more prospective studies with a larger sample size and longer follow-up period.Levels of Evidence: Level II: Prognostic.

The Value of Preseason Screening for Injury Prediction: The Development and Internal Validation of a Multivariable Prognostic Model to Predict Indirect Muscle Injury Risk in Elite Football (Soccer) Players

BackgroundIn elite football (soccer), periodic health examination (PHE) could provide prognostic factors to predict injury risk.ObjectiveTo develop and internally validate a prognostic model to predict individualised indirect (non-contact) muscle injury (IMI) risk during a season in elite footballers, only using PHE-derived candidate prognostic factors.MethodsRoutinely collected preseason PHE and injury data were used from 152 players over 5 seasons (1st July 2013 to 19th May 2018). Ten candidate prognostic factors (12 parameters) were included in model development. Multiple imputation was used to handle missing values. The outcome was any time-loss, index indirect muscle injury (I-IMI) affecting the lower extremity. A full logistic regression model was fitted, and a parsimonious model developed using backward-selection to remove factors that exceeded a threshold that was equivalent to Akaike’s Information Criterion (alpha 0.157). Predictive performance was assessed through calibration, discrimination and decision-curve analysis, averaged across all imputed datasets. The model was internally validated using bootstrapping and adjusted for overfitting.ResultsDuring 317 participant-seasons, 138 I-IMIs were recorded. The parsimonious model included only age and frequency of previous IMIs; apparent calibration was perfect, but discrimination was modest (C-index = 0.641, 95% confidence interval (CI) = 0.580 to 0.703), with clinical utility evident between risk thresholds of 37–71%. After validation and overfitting adjustment, performance deteriorated (C-index = 0.589 (95% CI = 0.528 to 0.651); calibration-in-the-large = − 0.009 (95% CI = − 0.239 to 0.239); calibration slope = 0.718 (95% CI = 0.275 to 1.161)).ConclusionThe selected PHE data were insufficient prognostic factors from which to develop a useful model for predicting IMI risk in elite footballers. Further research should prioritise identifying novel prognostic factors to improve future risk prediction models in this field.Trial registrationNCT03782389

Agreement Between Dribble and Change of Direction Deficits to Assess Directional Asymmetry in Young Elite Football Players

This study aimed to examine the agreement between asymmetries of dribble and change of direction (COD) deficits and to determine their potential difference to each other. Sixteen young elite football players were recruited and tested for sprint (over 10 m), dribbling (90°CODdribbling) and COD (90°CODrunning) performance in dominant (fastest) and non-dominant (slowest) directions. Dribble and COD deficits were computed to express dribbling and COD ability without the influence of acceleration. The asymmetric index (AI%) of both dribble and COD deficits were obtained for both directions. The level of agreement between dribble and COD deficits was assessed by Cohen’s kappa statistic (κ). Results showed that AI% measured by dribble and COD deficits presented a poor level of agreement (κ = −0.159), indicating their imbalance did not favor the same direction. Moreover, AI% of the dribble deficit was significantly higher than those of the COD deficit. This study demonstrated that asymmetries in dribbling and change of direction performance (measured by dribble and COD deficit) were not in agreement to favor the same direction, also displaying a significant difference to each other. Practitioners should consider the task-specificity of asymmetry to reduce the imbalance in dribbling and COD performance.

Effects of training intensity and environmental condition on the hydration status of elite football players

ABSTRACT Objective: To examine the effects of training intensity and environmental condition on the hydration status of Elite football players. Methods: Eleven elite football players completed three training sessions of varying intensity in cool (12°C) and warm (23°C) environments. Training demands was measured by Global Positioning System, sweat rate and sweat sodium concentration were measured using dermal patches and body mass change. Results: Warm condition increased sweat rate (0.9 ± 0.3 vs 1.7 ± 0.3 L.h-1, P<0.001), fluid intake (0.7 ± 0.1 vs 1.5 ± 0.2 L, P<0.001), total sodium loss (1405 ± 340 vs 2946 ± 958 mg, P<0.001) and total sweat loss (1.4 ± 0.5 vs 2.5 ± 0.4 L, P<0.001) compared to cool. Training intensity increased sweat sodium concentration (16.1 ± 6.6 vs 54.6 ± 22.2 mmol.L-1, P<0.001) and sodium loss (779 ± 231 vs 1405 ± 340 mg) in both environmental conditions. Total sweat loss and sodium loss were positively correlated with total distance covered (r=0.48, P=0.005 and r=0.4, P=0.023, respectively), meanwhile sodium loss was also positively correlated with the total number of high-intensity efforts (r=0.35, P=0.045). Conclusions: The results show that training load and environmental condition have a major impact on the hydration status of elite football players, hence hydration strategies should be developed accordingly.

Elite Football Players of Bosnia and Herzegovinian and Kosovian Clubs and Differences in the Morphological Characteristics and Body Composition among them

Elite Football Players of Bosnia and Herzegovinian and Kosovian Clubs and Differences in the Morphological Characteristics and Body Composition among them

The Effect of One Session Acute Exercise on the Urinary Excretion of Urinary Gamma-Glutamyl Transferase, Protein and Creatinine Levels of Elite Football Players

The aim of the present study was to evaluate the effect of one session acute exercise on the urinary excretion of urinary Gamma-glutamyl transferase, protein and creatinine levels in elite football players. A total of 30 Premier League football players with a mean age (26.1±3.80), a mean height (180.01±7.39), a mean weight (78.6±9.26) and a mean body mass index (24.87±1.13) were voluntarily and purposefully selected as statistical samples. The urinary sample of the players was collected in two stages. In the first stage, the players&amp;#39; urinary samples were taken on the rest day when they had not exercised for 24 hours. In the second stage, it was taken immediately after exercise and transferred to the laboratory. To test the hypotheses, especially to compare urinary protein, creatinine, and gamma-glutamyl transferase levels before and after exercise, and to compare excretion levels of protein, creatinine, and gamma-glutamyl transferase between the positions, ANOVA test was used. There was a significant difference between the levels of gamma-glutamyl transferase, proteinuria and creatinine before and after exercise (P

Individual Response to External Training Load in Elite Football Players.

To investigate within-player effect, between-player effect, and individual response of external training load from player tracking devices on session rating of perceived exertion training load (sRPE-TL) in elite football players. The authors collected sRPE-TL from 18 outfield players in 21 training sessions. Total distance, high-speed running distance (>14.4m/s), very high-speed running distance (>19.8m/s), PlayerLoad™, PlayerLoad2D™, and high-intensity events (HIE > 1.5, HIE > 2.5, and HIE > 3.5m/s) were extracted from the tracking devices. The authors modeled within-player and between-player effects of single external load variables on sRPE-TL, and multiple levels of variability, using a linear mixed model. The effect of 2 SDs of external load on sRPE-TL was evaluated with magnitude-based inferences. Total distance, PlayerLoad™, PlayerLoad2D™, and HIE > 1.5 had most likely substantial within-player effects on sRPE-TL (100%-106%, very large effect sizes). Moreover, the authors observed likely substantial between-player effects (12%-19%, small to moderate effect sizes) from the majority of the external load variables and likely to very likely substantial individual responses of PlayerLoad™, high-speed running distance, very high-speed running distance, and HIE > 1.5 (19%-30% coefficient of variation, moderate to large effect sizes). Finally, sRPE-TL showed large to very large between-session variability with all external load variables. External load variables with low intensity-thresholds had the strongest relationship with sRPE-TL. Furthermore, the between-player effect of external load and the individual response to external load advocate for monitoring sRPE-TL in addition to external load. Finally, the large between-session variability in sRPE-TL demonstrates that substantial amounts of sRPE-TL in training sessions are not explained by single external load variables.

Return to football training and competition after lockdown caused by the COVID-19 pandemic: medical recommendations.

The lockdown caused by the COVID-19 pandemic represents a great unknown regarding the physiological changes induced in elite football players. Although it will differ from country to country, the return to sport for professional football players will follow a forced lockdown never experienced and longer than the normal annual season break. Moreover, in addition to an obvious decrease in performance, the lockdown will possibly lead to an increase of the injury risk. In fact, preseason is always a period with a specific football injury epidemiology, with an increase in the incidence and prevalence of overuse injuries. Therefore, it seems appropriate to recommend that specific training and injury prevention programmes be developed, with careful load monitoring. Training sessions should include specific aerobic, resistance, speed and flexibility training programmes. The aerobic, resistance and speed training should respect some specific phases based on the progressiveness of the training load and the consequent physiological adaptation response. These different phases, based on the current evidence found in the literature, are described in their practical details. Moreover, injury prevention exercises should be incorporated, especially focusing on overuse injuries such as tendon and muscle lesions. The aim of this paper is to provide practical recommendations for the preparation of training sessions for professional footballers returning to sport after the lockdown.

Concentration of salivary cortisol and testosterone in elite women football players

This study aims to evaluate the relation between salivary concentrations of cortisol (C), testosterone (T), the ratio T:C and the individual performance of top-level female soccer athletes during official matches. Eighteen female athletes from a national soccer team (age 23.06 ± 4.33 years) participated in the study. Four official matches were analysed and the on-field time of each player as well as the index of individual effectiveness were calculated. Players were classified in two clusters according to their individual performance (cluster 1 – poor individual performance; cluster 2 – good individual performance) using K-means and their hormonal variables were compared. The players of cluster 2 generally revealed higher values (p˂.05) in both the positive actions and individual effectiveness, when compared with the players of cluster 1. The players of both clusters presented identical values of C, T and T:C at the four evaluated matches. The athletes of cluster 2 showed a significant increase in C (p˂.05) and a significant decrease in T and T:C before the games lost (M2 and M5). However, there was no linear relation between the variation of both hormones during the matches and the individual performance of players. Performance in competition revealed significant differences between players, though with no apparent relation to the hormonal kinetics of C and T before and after the matches.

Elite Football Players of Bosnia and Herzegovinian and Kosovian Clubs

Elite Football Players of Bosnia and Herzegovinian and Kosovian Clubs

Analyzing the effects of combined small-sided games and strength and power training on the fitness status of under-19 elite football players.

The purpose of this study was twofold: 1) to characterize a common microcycle considering both internal and external training loads; and 2) to identify the effects of small-sided games (SSGs) and of power and strength training on the fitness status of football players. Fifteen male football players (age: 18.55±0.39 years) participated in this study. Ninety-two consecutive training sessions were monitored and analyzed over a period of nineteen weeks. Rating of perceived exertion (RPE ) was used as an internal load marker, and the distances covered at different speed thresholds and accelerations/decelerations were used as external load markers to characterize the common microcycle. Participants' body composition, vertical jumping ability, maximal strength, speed, and agility were assessed twice before and after the training monitoring process. The results revealed that match day -5 (MD-5) and MD-1 were associated with the lowest RPE scores (4.2 and 3.8 A.U., respectively). MD-4 and MD-3 were associated with the highest RPE values (9.2 and 8.8 A.U., respectively). Meaningful changes in RPE were found between training days. External load monitoring revealed that MD-4 had the highest values of accelerations and decelerations >2 m/s2/min (4.22 and 3.17, respectively) and MD-3 had the highest values of distance covered at high intensity (6.11 m/s2/min). Meaningful moderate improvements in jumping performance (d=0.90) and maximal strength parameters (d=0.83) were also found between assessments. It was identified that the concurrent approach had meaningful impacts on the fitness development of players and should be considered by coaches for future training interventions.