Search Results (249)

This study analyses the physical performance variables involved in different training tasks aimed at replicating the worst-case scenarios (WCSs) observed during official matches in professional football, with a focus on playing positions and occurrences within a 1 min period. Data were collected from 188 training sessions and 42 matches of a Spanish Second Division team during the 2021/2022 season. All data were reported on a per-player basis. GPS tracking devices were used to record physical variables such as total distance, high-speed running (HSR), sprints, accelerations, decelerations, and high metabolic load distance (HMLD). Players were grouped according to their match positions: central defenders, wide players, midfielders and forwards. The results showed that none of the training tasks fully replicated the physical demands of match play. However, task TYPEs 11 (Large-Sided Games) and 9 (small-sided games with orientation and transition) were the closest to match demands, particularly in terms of accelerations and decelerations. Although differences were observed across all variables, the most pronounced discrepancies were observed in sprint and HSR variables, where training tasksfailed to reach 60% of match demands. These findings highlight the need to design more specific drills that simulate the intensity of WCS, allowing for more accurate weekly training load planning. This study offers valuable contributions for optimising performance and reducing injury risk in professional footballers during the competitive period. Full article

Soccer, as a high-intensity sport, places significant physical demands on athletes and is associated with a high risk of injury. Electrical muscle stimulation (EMS), a training and rehabilitation technology, has gained attention for its potential benefits in sports settings. This systematic review, conducted under the PRISMA guidelines, rigorously assessed the effectiveness of EMS in improving muscle strength, promoting post-exercise recovery, and facilitating injury rehabilitation among soccer players. A comprehensive search of the PubMed, Scopus, and Web of Science databases identified 10 studies meeting the inclusion criteria. Among these, six studies demonstrated a significant improvement in athletic performance following local or whole-body EMS application. Four studies provided evidence supporting EMS’s efficacy in enhancing post-exercise recovery and reducing recovery time after injuries, with observed reductions in recovery time. However, the majority of the included studies were not double-blind, which limits the strength of the evidence. None of the included studies reported EMS-related adverse effects. Overall, the current results suggest that EMS may be a useful adjunct to improve athletic performance and facilitate recovery in soccer players. This review offers actionable insights for coaches and athletes regarding the safe and effective application of EMS in soccer training and rehabilitation programs. Full article

Background: The incidence of anterior cruciate ligament ruptures in football has experienced a marked increase in recent years, affecting both professional and amateur players. This injury is characterised by being highly disabling, causing the player to withdraw from the field of play for prolonged periods and there is no clear consensus on how to carry out the different phases of rehabilitation, which poses a major challenge for health professionals. Case presentation: This study followed a semi-professional player who suffered an anterior cruciate ligament tear following two forced valgus actions without direct contact in the same match. Outcome and follow-up: The patient underwent surgery using an autologous hamstring graft. He followed a progressive rehabilitation programme consisting of one preoperative phase and six phases after the operation. After a 12-month follow-up, with exercises aimed at perfecting step-by-step basic and specific physical skills, the player showed a complete functional recovery, achieving the desired parameters. Conclusions: This case highlights the importance of structured rehabilitation adapted to the specific needs of the football player through an approach with coherent progressions, which considers the muscle chains that determine the movements performed on the football pitch. Full article

The rapid proliferation of wearable sensors and advanced tracking technologies has revolutionized data collection in elite sports, enabling continuous monitoring of athletes’ physiological and biomechanical states. This study proposes a comprehensive big data analytics framework that integrates data acquisition, processing, analytics, and decision support, demonstrated through synthetic datasets in football, basketball, and athletics case scenarios, modeled to represent typical data patterns and decision-making workflows observed in elite sport environments. Analytical methods, including gradient boosting classifiers, logistic regression, and multilayer perceptron models, were employed to predict injury risk, optimize in-game tactical decisions, and personalize sprint mechanics training. Key results include a 12% reduction in hamstring injury rates in football, a 16% improvement in clutch decision-making accuracy in basketball, and an 8% decrease in 100 m sprint times among athletes. The framework’s visualization tools and alert systems supported actionable insights for coaches and medical staff. Challenges such as data quality, privacy compliance, and model interpretability are addressed, with future research focusing on edge computing, federated learning, and augmented reality integration for enhanced real-time feedback. This study demonstrates the potential of integrated big data analytics to transform sports performance optimization, offering a reproducible and ethically sound platform for advancing personalized, data-driven athlete management. Full article

Background and Objectives: Anterior cruciate ligament (ACL) injury rates remain high and have a significant impact on female football players. This study aims to evaluate knee kinematics and lower limb muscle activity in players at risk of ACL injury compared to healthy players through three side-cutting tests. It also investigates how the amplitude of a change in direction influences stabilization parameters. Materials and Methods: A cross-sectional case–control study was conducted with 16 second division female futsal players (23.93 ± 5.16 years), divided into injured (n = 8) and healthy groups (n = 8). Injured players had a history of non-contact knee injury involving valgus collapse, without undergoing surgical intervention. Three change of direction tests, namely the Change of Direction and Acceleration Test (CODAT), Go Back (GOB) test, and Turn (TURN) test, were used for evaluation. The peak and range of knee joint angles and angular velocities across three planes, along with the average rectified and peak envelope EMG signals of the Biceps Femoris (BF), Semitendinosus (ST), Vastus Medialis (VM), and Lateral Gastrocnemius (LG), were recorded during the preparation and load phases. Group differences were analyzed using two-factor mixed-model ANOVA with pairwise comparisons. Statistical significance was set at p < 0.05. Results: Injured players demonstrated lower external tibial rotation angular velocity and a greater range of motion in tibial external rotation compared to healthy players. Additionally, the injured group showed significantly higher average rectified muscle activity in VM and LG both increased by 4% during the load phase. The CODAT and TURN tests elicited higher BF and VM muscle activity, compared to the GOB test. The TURN test also showed greater extension angular velocity in the sagittal plane. Conclusions: The results revealed differences in knee kinematics and muscle activity between players at risk of ACL injury and healthy players, influenced by the amplitude of directional changes. Players altered transverse plane mechanics and increased VM and LG activation during LOAD may reflect a dysfunctional motor pattern, while the greater sagittal plane angular velocity and VM and BF activation from the CODAT and the TURN test highlight their higher potential to replicate ACL injury mechanisms compared to the GOB test. Full article

Background: High-intensity actions like accelerations and decelerations, often performed unilaterally, are crucial in elite female football but increase the risk of interlimb asymmetries and injury. Flywheel resistance training enhances eccentric strength, yet limited research has assessed how different inertial loads affect mechanical outputs in unilateral exercises. Purpose: This study investigated how two inertial loads (0.107 kg·m² and 0.133 kg·m²) influence power, acceleration, speed, and asymmetry during unilateral hip extensions in elite female footballers. Methods: Eighteen professional players (27 ± 4 years, 59.9 ± 6.5 kg, 168.2 ± 6.3 cm, BMI 21.2 ± 1.8) completed unilateral hip extensions on a conical flywheel under both inertia conditions. A rotary encoder measured peak/average power, acceleration, speed, and eccentric-to-concentric (E:C) ratios. Bilateral asymmetries between dominant (DL) and non-dominant (NDL) limbs were assessed. Paired t-tests and Cohen’s d were used for analysis. Results: Higher inertia reduced peak and mean acceleration and speed (p < 0.001, d > 0.8). Eccentric peak power significantly increased in the NDL (p < 0.001, d = 3.952). E:C ratios remained stable. Conclusions: Greater inertial loads reduce movement velocity but increase eccentric output in the NDL, offering potential strategies to manage neuromuscular asymmetries in elite female football players. Full article

This study aimed to compare the external peak physical demands (PDs) of under-19-year-old (U19) and professional male football players according to playing position. Positional data derived from Global Positioning System (GPS) tracking during 15 matches in the 2023/24 season for both groups were analyzed. The following variables were measured: total distance, high-intensity running distance, sprint distance, acceleration count, and high-intensity actions. A linear mixed-effects model was employed, with category and playing position included as fixed effects to compare these metrics at the player level. The results revealed only a few significant differences in physical demands between the U19 and professional players. Notably, central defenders and central midfielders exhibited lower performance in HSR distance compared to other positions, with the professional players registering higher values than their U19 counterparts. However, no significant differences were observed for total and relative sprint distances, the number of accelerations, high intensity and relative sprint running efforts. These findings highlight the overall similarity in physical demands between U19 players and professional players, suggesting that elite youth athletes may be adequately prepared to meet the physical challenges of professional competition, with the exception of HSR distance. These conclusions have practical implications for coaches and performance staff, supporting the development of position-specific training programs, optimizing workload management through GPS monitoring, improving microcycle planning, and enhancing injury prevention strategies. Full article

Background: The high demands of professional soccer predispose players to musculoskeletal injuries. The primary challenge for identifying potential risk factors lies in determining the appropriate assessment methods and indicators to consider. Kinetic variables have been identified as potential indicators of injury risk. Objectives: To conduct a systematic review of the literature analyzing the relationship between kinetic variables and the risk of indirect musculoskeletal injuries of the lower limb in professional soccer players. Methods: A search was conducted on Web of Science, PubMed, and Scopus following the PRISMA guidelines. The search included articles that link kinetic variables assessed through dynamometry to indirect lower limb injuries. Sample characteristics, assessments, injury follow-ups, and statistical results were extracted for qualitative synthesis. Results: A total of 1096 studies were initially identified, of which 380 duplicates were removed. After screening 716 articles by title and abstract, 631 were excluded. Subsequently, 85 full-text articles were examined, resulting in 11 studies being included. Of the included articles, 10 used isokinetic dynamometry and the Nordic hamstring curl test to assess lower limb strength. Conclusions: The results of this review indicate that kinetic variables, particularly isokinetic strength measures at different angular velocities, are consistently associated with indirect musculoskeletal injury risk in professional soccer players. The most relevant indicators include eccentric hamstring force and concentric quadriceps torque, which help identify strength deficits and muscular disequilibrium. Monitoring these variables through validated assessments enables the development of targeted prevention strategies. Additionally, injury risk assessment should integrate kinetic data with contextual indicators such as well-being, fatigue, and training load. Full article

Background/Objectives: Lower extremity non-contact injuries (LE-NCIs) pose a significant burden on the National Football League (NFL), with ongoing debates regarding playing surface safety. The stressful college-to-professional transition period for rookies, which can include adapting to new playing surfaces, may influence injury susceptibility. This study aimed to determine whether the transition in a home stadium turf type (natural grass, artificial, and hybrid) from the final college season to the rookie NFL season impacts LE-NCI likelihood. Methods: A retrospective cohort study analyzed 826 first and second-round NFL draft picks from 2012 to 2024. Data on college/NFL home surfaces (defining six transition types), position group, college training surface access, and rookie season LE-NCIs were collected from public sources. Competing risk analysis was used to estimate the cumulative LE-NCI incidence. Multivariable logistic regression assessed the association between turf transition and LE-NCI risk, adjusting for position, draft cohort, and college training access. Results: During their rookie season, 21.2% (175/826) of players sustained an LE-NCI. Skill position players had significantly higher adjusted odds of LE-NCI compared to hybrid players (AOR = 1.88; 95% CI: 1.20–2.97; p = 0.006). No specific turf transition category showed a statistically significant association with LE-NCI risk compared to the Grass-to-Grass reference in adjusted models. College training surface access was also not significantly associated with risk (AOR = 0.97; 95% CI: 0.65–1.45; p = 0.874). Cumulative LE-NCI incidence reached 33.1% by season end, with risk accelerating between weeks 4 and 10. Conclusions: Home stadium turf-type transition from college to the NFL was not significantly associated with LE-NCI risk in this rookie cohort, suggesting that surface transitions may not be a primary risk factor during the professional transition period. However, our analysis revealed significant position-dependent injury patterns (skill players: AOR = 1.88) and a temporal clustering of injuries between weeks 4 and 10, indicating that rookie LE-NCI prevention strategies should prioritize position-specific interventions and enhanced monitoring during the early- to mid-season high-risk period rather than surface transition-based approaches. Full article

Physiological characteristics such as VO_2max, running economy (RE), maximal aerobic speed (MAS), maximal sprinting speed (MSS), anaerobic speed reserve (ASR), and player profiling (based on MSS and MAS) have been proven to be important for training prescriptions in football. However, previous studies on player profiling have neglected the absolute values of MSS and MAS. The objectives of this study were to compare the aforementioned physiological variables among player roles, create benchmarks, and provide normative data to help coaches categorize players, ultimately proposing a new player profiling method. We analyzed 195 male professional football players (50 forwards, 59 midfielders, 44 full-backs, and 42 center-backs). Multivariate analysis of variance with Tukey’s post hoc tests revealed positional differences. Center-backs exhibited lower VO_2max than midfielders and full-backs. Both center-backs and forwards showed poorer RE and MAS compared to midfielders and full-backs. Full-backs achieved higher MSS than midfielders and center-backs, and forwards outperformed center-backs. Finally, midfielders demonstrated lower ASR than all other positions. Benchmarks based on T-scores for all variables were provided. Finally, in the new profiling method proposed—also based on T-scores—players were classified as “speed”, “endurance”, or “hybrid” if their MAS and/or MSS T-score exceeded 60, “in development” if both were below 45, and “average” if both scores were between 45 and 60 without any value above 60. The normative data provided can assist coaches in identifying specific areas for improvement in players’ physical conditioning—particularly valuable for youth athletes or those returning from injury. Additionally, the new profiling method offers insights into individual player characteristics, enabling more tailored and effective training interventions. Full article

Objectives: Soccer is the most practiced sport around the world. The injury incidence has an estimated rate of up to 70 injuries per 1000 h of play. FIFA 11+ is a program designed to prevent injuries and optimize performance. The purpose of this study was to analyze the acute effects of this program as a warm-up on different functional, physiological, and mechanical properties of various knee tissues and whether there were differences between genders. Methods: The sample included 45 recreational soccer players. Several muscular and tendon mechanical properties, muscular oxygen saturation, electromyography, maximum voluntary contraction, and rate of force development were analyzed, before and after performing the FIFA 11+. Results: Only a moderate significant increase in muscle oxygen saturation in men from pre- to post-test was reported. No other parameters showed statistically significant differences between groups, suggesting that the intervention may lack clinical relevance. The reported effect sizes were mostly trivial, so differences are unlikely to have significant practical relevance. Statistical analyses were performed using a 2 × 2 factorial repeated measures factorial ANOVA with Bonferroni post hoc comparisons. Conclusions: FIFA 11+ warm-up does not provide a sufficient stimulus to elicit mechanical or metabolic responses in the per-knee structures. Other warm-up designs may be more appropriate for finding these effects. Full article

Background: To the best of the authors’ knowledge, the different injury mechanisms of the hamstring muscle group have not been defined in detail in men’s professional football. For this reason, the main aim of this study is to determine the mechanisms and contextual patterns associated with hamstring muscle group injuries in professional male football players in competition, using a systematic video analysis method. Methods: Video recordings of official matches from two consecutive seasons (2017/18 and 2018/19) of the Spanish First Division of Football (LaLiga^TM) were used for this research. The process to determine the moment of injury was carried out by two independent evaluators using an ad hoc observation tool and, subsequently, all relevant data were collected to detail the specific patterns of injury events observed. Results: In total, 78 cases of hamstring injuries were included for the final analysis of specific patterns. The most outstanding results were that, (1) although the sprint-related pattern (SP) is predominate (54%; 42 cases), the combined pattern 2 (COMB2) is another mechanism that appears frequently (26%; 20 cases), (2) within the SP, curved runs show a greater number of cases (52% of SP; 22 cases), (3) the majority of the injuries occur without contact (83%; 65 cases) and with the presence of the ball (88%; 69 cases), and finally, (4) the most injured positions were fullbacks/wingbacks (28%; 22 cases), central defenders (27%; 21 cases), and wingers/wide midfielders (23%; 18 cases). Conclusions: The SP remains the most frequent pattern in hamstring injuries; however, the present study presents other mechanisms that are also quite common and should be considered, such as curvilinear runs in SP and COMB2. Full article

Air pollution is an escalating global concern with significant implications for human health and athletic performance. This narrative review synthesizes and critically compares the current literature on the impact of air pollution on health and football performance, elucidates the physiological mechanisms involved, and evaluates available mitigation strategies. Comparative studies consistently demonstrate that football players—who frequently engage in high-intensity outdoor exercise—are particularly susceptible to the harmful effects of airborne pollutants such as particulate matter (PM), volatile organic compounds (VOCs), nitrogen dioxide (NO₂), ozone (O₃), and carbon monoxide (CO). These pollutants bypass natural respiratory defenses due to increased pulmonary ventilation during exercise, reaching deeper lung regions and triggering oxidative stress, inflammation, and impaired lung function. Evidence across studies indicates that poor air quality is associated with decreased football performance, including reduced distance covered, fewer high-intensity efforts, elevated physiological strain, and diminished training adaptation. Long-term exposure exacerbates respiratory conditions, suppresses immune function, and heightens the risk of illness and injury. Furthermore, comparative genetic research highlights inter-individual variability in pollution sensitivity, with specific gene variants conferring either increased vulnerability or resilience to adverse effects. This review also explores practical and emerging mitigation strategies—such as timing training to avoid peak pollution, utilizing air quality monitoring and antioxidant-rich diets, and promoting sustainable infrastructure—to safeguard athlete health and optimize performance. Novel approaches including respiratory training, anti-smog masks, indoor sessions, and personalized recovery protocols offer additional protection and recovery support. Full article

Background: Previous studies have tested the association between the COL5A1 rs12722 polymorphism and the risk of anterior cruciate ligament (ACL) injury. Overall, their results are contradictory because most studies used relatively small samples and data from ACL ruptures during sport activities have been mixed with ruptures suffered in non-sporting contexts. Objective: To examine the association between the COL5A1 rs12722 polymorphism and the prevalence of ACL rupture in a homogeneous sample of professional male football players. Methods: A total of 268 professional male football players participated in this study. The COL5A1 rs12722 genotype (CC, CT and TT) was obtained from each player using genomic DNA samples obtained from a buccal swab and measured with PCR RFLP. Players with history of ACL rupture during their professional career were identified by the medical staff of each team. Only ACL injuries obtained during football exposure were considered for this investigation. In this process, we identified 49 ACL ruptures pertaining to 43 players suffered between 2013 and 2024. The situational pattern (i.e., attacking or defending, type of football action, moment of the season, match/training exposure, etc.) was also obtained for each injury. A sub-analysis of non-contact ACL ruptures was conducted, as these injuries are more likely to be influenced by genetic factors. Results: The distribution of genotypes was similar in players with history of ACL rupture (n = 43; CC/CT/TT, 24.4/48.9/26.7%) and with no history of ACL rupture (n = 225; 25.3/49.8/24.9%; p = 0.973). Overall, the prevalence of players with history of ACL injury was 16.2% for the whole group of CC players (11 out of 68 players), 16.4% for whole group of CT (22 out of 135 players) and 15.2% for the group of TT players (10 out of 66 players; p = 0.973). However, the COL5A1 rs12722 genotype affected the dominance of the injured leg (p = 0.012), the type of action that originated the injury (p = 0.047), and the distribution of non-contact ACL injuries depending on the time of the match (p = 0.020). Specifically, CC players suffered ruptures predominantly in the dominant leg, when landing or reaching (offensive actions) and in the last 15 min of the match (all p < 0.050). On the contrary, TT players had ACL ruptures predominantly in their non-dominant leg, when pressing the opponent (defensive actions) and in the first 15 min of the match (all p < 0.050). Conclusion: There was no association between any of the COL5A1 rs12722 genotypes and the overall prevalence of ACL rupture in professional football players. However, the COL5A1 rs12722 polymorphism appeared to influence specific characteristics of the injury, such as the type of action leading to the rupture and the timing within the match, suggesting a potential genetic contribution to injury susceptibility. Full article

This longitudinal study investigated the incidence and characteristics of injuries among U9, U11, and U13 male football players in an academy setting over a six-season period, from 2016/17 to 2021/22. A total of 374 injuries were analyzed, with a particular focus on muscle injuries, including Delayed Onset Muscle Soreness (DOMS), muscle ruptures, and contusions. The study revealed that the highest injury incidence occurred in the U13 group, with quadriceps injuries being most prevalent in both the U13 and U11 groups. The study found that muscle injuries accounted for a significant proportion of all injuries, particularly in the U13 group, where muscle injuries increased over time. Intrinsic factors such as physical development during puberty and extrinsic factors like training intensity and psychological pressures may contribute to the higher injury rates in older age groups. Additionally, seasonal fluctuations in injury rates were observed, with a notable decline during the COVID-19 lockdowns in 2019/20 and 2020/21, followed by an increase post-lockdown due to deconditioning. The study highlights the vulnerability of young athletes to muscle injuries, particularly during growth spurts, and calls for further research into training methods and injury prevention strategies to mitigate these risks. Full article