As previous literature updates, I have performed a PubCrawler search looking for football articles in NCBI Medline (PubMed) and GenBank databases.
Following studies were retrieved for this week:
1 Inter-Segmental Coordination During Soccer Instep Kicking: A Vector-Coding Comparison Between Experienced Athletes and Novices
Reference: Bioengineering (Basel). 2025 Oct 24;12(11):1151. doi: 10.3390/bioengineering12111151.
Authors: Liwen Zhang, Meizhen Zhang, Hui Liu
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12649761/pdf/bioengineering-12-01151.pdf
Summary: The purpose of this study was to characterize the inter-segmental coordination of hip, knee, and ankle movement of the kicking leg during instep kicking for experienced athletes and novices, using vector coding as a non-linear technique. Motion capture and electromyographic data were collected for 14 soccer-majored college students and 32 novices performing the instep kicking task. The percentage of time spent on the coordination patterns, defined based on hip-knee and knee-ankle coupling angles, was calculated and compared. The agonist-antagonist activity ratio was calculated and compared. The time percentages of the knee-ankle shank dominance of the experienced athletes during the whole kicking movement were significantly greater than those of the novices (p < 0.050). Athletes achieving greater maximum ball speed had more knee flexion dominant coordination patterns in the back swing and leg-cocking, and knee extension dominant coordination patterns in the leg acceleration phase. The lower activity ratio of the tibialis anterior and gastrocnemius muscles contributed significantly to increasing kicking accuracy. These results underscore the value of vector coding in identifying key inter-segmental coordination features and directly support targeted soccer kick training. The dynamic stability exercises involving knee flexion and extension to optimize power transfer for speed, as well as activation and relaxation control exercises of the lower leg muscles to improve the kicking accuracy, may be effective ways to enhance instep kicking motor control ability and performance for soccer athletes.
2 Acute Metabolic, Mechanical, and Perceptual Responses to Curve Versus Linear Repeated-Sprint Training in Highly Trained Youth Soccer Players
Reference: Int J Sports Physiol Perform. 2025 Nov 26:1-9. doi: 10.1123/ijspp.2024-0421. Online ahead of print.
Authors: Andrés Baena-Raya, José María Ruiz-Zaragoza, David M Díez-Fernández, Ezequiel Rey, Marcos A Soriano, Alejandro Pérez-Castilla, Manuel A Rodríguez-Pérez, Alexis Padrón-Cabo
Summary: This study aimed to (1) evaluate the acute metabolic, mechanical, and perceptual responses to curve versus linear repeated-sprint-training (RST) protocols in highly trained youth soccer players and (2) analyze whether the sprint trajectory influences the time course of recovery following RST protocols. Twenty-seven highly trained youth soccer players randomly performed 2 RST protocols (12 × 17 m with 15-s intervals) with different trajectories: linear or curve (radius of 9.15 m). Blood lactate concentration, countermovement-jump height, modified reactive strength index, and myotonometric measurements of the biceps femoris long head (stiffness, frequency, and decrement) were assessed before and 0 minutes, 5 minutes, and 24 hours after the protocols. Likewise, best and average sprint velocities were recorded in both protocols, and perceptual responses were evaluated using Borg and Hooper scales. Linear RST showed higher velocity outputs than curve RST (P < .001). No significant time × condition interactions were observed for blood lactate concentration, countermovement-jump height, modified reactive strength index, time to takeoff, or myotonometric measurements (all P < .05), except for right-leg stiffness (P = .047), which significantly increased from 0 minutes to 24 hours only after curve RST (P < .05). Additionally, players also reported poorer sleep quality (P = .045) following the curve RST. Overall, these findings suggest that the acute metabolic, mechanical, and perceptual demands of RST are not trajectory dependent. Therefore, strength and conditioning coaches can use both trajectories to address soccer-specific sprint demands in elite youth soccer players.
3 Training Load, Mileage, and Perceived Exertion as a Predictive Model of Injury and Illness in Women’s Soccer
Reference: Sports (Basel). 2025 Nov 17;13(11):411. doi: 10.3390/sports13110411.
Authors: Corbit Franks, Andrew Yockey, Nicholas Bosley, Tyler Myers, Kaitlyn Armstrong, Melinda Valliant, Chip Wade
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12656130/pdf/sports-13-00411.pdf
Summary: This study examined the relationship between training load, mileage, and session rating of perceived exertion (s-RPE) as predictors of injury and illness in Division I women’s soccer players. Twenty-four athletes were monitored over a 13-week season including 69 athlete exposures (49 training sessions and 20 matches). Internal and external load were measured during each athlete exposure. Player injury and illness status were documented daily by medical staff and categorized as healthy, medical attention, or time-loss. Associations between athlete exposures and injury/illness status were analyzed using a mixed-effects ordinal logistic regression model with player ID as a random intercept. A total of 1560 athlete observations were included. Higher daily mileage was associated with increased odds of injury or illness (OR = 1.67, 95% CI: 1.19-2.34). Training load was associated with reduced odds of injury or illness, with each unit increase lowering the odds by 42% (OR = 0.58, 95% CI: 0.41-0.83). Session-RPE was not significantly associated with injury or illness (OR = 0.96, 95% CI: 0.65-1.42). These findings indicate that accumulated mileage elevates injury and illness risk, while structured increases in training load enhance athlete resilience, and reduce injury and illness risk. Monitoring both internal and external workload provides performance staff with a practical approach to optimize training stress, augment recovery, and prepare athletes for the demands of competition in women’s soccer.
4 Foot Morphology and Plantar Pressures in Elite Male Soccer Players-A Baropodometric On-Field Dynamic Assessment
Reference: Sports (Basel). 2025 Nov 13;13(11):408. doi: 10.3390/sports13110408.
Authors: Pablo Vera-Ivars, Juan Vicente-Mampel, Oscar Fabregat-Andrés, Carlos Barrios
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12656522/pdf/sports-13-00408.pdf
Summary: Numerous overuse injuries affecting the lower limbs of elite athletes have been associated with biomechanical alterations in plantar loading of the foot. This study aimed to analyze the plantar pressure distribution in elite male soccer players and its relationship with various morphological and functional factors, including foot type, metatarsal and digital alignment, and on-field position. Dynamic foot pressure measurements were obtained from 21 soccer players who participated in the UEFA Champion League. The participants had an average age of 27 years, with an average height of 180.9 cm, weight of 76.9 kg, and BMI of 23.4. An insole system (BioFoot/IBV) with telemetry transmission was employed to record plantar loading patterns during normal gait and running. During the support or contact phase, the central and medial metatarsal areas exhibited the highest peak pressure under both walking and running conditions. When walking, the right foot exerted 13-60% more pressure on the outer metatarsal and toe areas. The left foot experienced up to 13% more peak pressure in the middle metatarsal area. During running, the total pressure difference between the feet ranged from -8% to +19%. The right foot usually had more peak pressure on the heel and first toe. In players with valgus feet, the pressure in the central metatarsal area increased from 1086 kPa (walking) to 1490 kPa (running), representing a 37% increase. Conversely, in players with cavus-varus feet, the pressure in this central area increased from 877 kPa to 1804 kPa, a 105% increase. Foot morphology and playing position significantly influenced the plantar pressure patterns in elite soccer players. The central metatarsal region bears the highest load, particularly during running, with distinct variations across foot types and field positions. These findings highlight the need for individualized biomechanical assessments to prevent overuse injuries and optimize performance.
5 Effects of Combined Repeated Sprint and Large-Sided Game Training on Physical Performance in Elite U20 Soccer Players: A Randomised Controlled Trial
Reference: Sports (Basel). 2025 Nov 5;13(11):394. doi: 10.3390/sports13110394.
Authors: Mehdi Ben Brahim, Bekir Erhan Orhan, Hussain Yasin, Shaher A I Shalfawi
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12656217/pdf/sports-13-00394.pdf
Summary: The purpose of the present study was to investigate the impact of a combined Repeated Sprint Training (RST) with Large-Sided Soccer Games (LSSG) on soccer players‘ physical performance indicators. A randomised controlled trial protocol was designed and implemented to examine the effects of an 8-week training programme on the physical performance of U20 national team soccer players. Participants were randomly assigned after matching them based on their pre-test results from a 30 m sprint to one of two groups: an experimental group (EG; n = 16) and a control group (CG; n = 10). The EG took part in two extra training sessions per week, which included RST and LSSG, whereas the CG stuck to their usual training routine. Sprint, Repeated sprint ability (RSA), vertical jump, the New Multi-Change of Direction Agility Test (NMAT), and the 15 m ball dribbling agility test performances were assessed. The main findings from this study indicate that the EG showed statistically significant improvements in short sprint performance (5 m), vertical jump height (SJ and CMJ), agility (NMAT), RSA, and fatigue tolerance, with moderate to large effect sizes. The CG showed no statistically significant changes, though some small to moderate effect sizes were observed. The findings suggest that this hybrid method has the potential to produce improvements in specific performance domains, particularly agility and fatigue tolerance, beyond what may be expected from regular soccer training alone.
6 Stress-Induced „Immediate“ Lactate (iBLC) Response Differences in Pubertal and Young Adult Soccer Players
Reference: Sports (Basel). 2025 Nov 4;13(11):384. doi: 10.3390/sports13110384.
Authors: Ferenc Ihász, Ottó Vincze, Imre Soós, István Barthalos, Zoltán Alföldi, Anna Horváth Pápai, Ádám Balog, László Suszter
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12656138/pdf/sports-13-00384.pdf
Summary: High-intensity physical activity elicits acute physiological responses across the metabolic, cardiovascular, respiratory, endocrine, immune, and neuromuscular systems. During recovery, multiple processes act to restore homeostasis and functional capacity. The aim of this study was to examine age- and position-related differences in cardiovascular and metabolic responses among youth soccer players. A total of 147 male academy soccer players were assessed, divided into four age groups (U15, U16, U17, U18/U19) and four playing positions (defenders, midfielders, forwards, goalkeepers). Significant anthropometric and physiological differences were observed between age groups. Body height and weight increased progressively with age (p < 0.05), while body fat percentage was lower in younger compared to older cohorts (p < 0.001). Relative muscle mass did not differ significantly between groups. Absolute aerobic capacity (VO2max) was higher in U17-U19 compared to U15-U16 (p < 0.001). Heart rate at anaerobic threshold (HRAT) and maximal heart rate were greater in the younger groups (p ≤ 0.005). Immediate blood lactate (iBLC) and ΔiBLC were significantly higher in U15-U16 compared to U17-U19 (both p < 0.001). Position-specific analysis revealed higher iBLC in U15 defenders compared to U18/U19 defenders (p < 0.01), whereas no positional differences were observed in relative VO2max. These results are due to a carefully designed training program and frequent individual training sessions.
7 Does Birth Month Matter? Effects of Birth Subgroupings on Motor Performance and Ball-Involving Tests in a Youth Soccer Academy
Reference: Sports (Basel). 2025 Nov 4;13(11):382. doi: 10.3390/sports13110382.
Authors: Lorenzo Marcelli, Fioretta Silvestri, Gianluca Di Pinto, Andrea Colombo, Federica Marzoli, Maria Chiara Gallotta, Laura Guidetti, Fabrizio Perroni, Davide Curzi
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12656536/pdf/sports-13-00382.pdf
Summary: Youth motor performance changes are not strictly linear during their sports career, and within-year birth timing may introduce relative age differences, known as the relative-age effect. In a cross-sectional study of 170 male young soccer players (8-12 years old), field tests were compared between adjacent age groups and within each of them: countermovement jump (with and without arm swing); 15 m linear sprint and agility test with and without the ball. Non-parametric tests with post hoc comparisons revealed significant differences between consecutive birth years in physical skills, particularly between the youngest and oldest groups. Specifically, differences were noted in the jumping test between U12 and U11, and between U10 and U9. Additionally, linear sprint and agility tests showed significance in U13 versus U12 and U10 versus U9. Finally, dribbling skills mature later (in both tests, U13 v U12, U12 v U11; with the ball, U10 v U9). Differences were found within the groups based on the semester, but not the trimester of birth, confirming a progressive yet non-linear pattern and semester-level within-year differences. These findings suggest the key role of motor skills development trajectories in creating individualized training programs tailored to the needs of individual young soccer players.
8 Relationship Between Internal and External Load in Under-16 Soccer Players: Heart Rate, Rating of Perceived Exertion, and GPS-Derived Variables
Reference: Sports (Basel). 2025 Nov 3;13(11):376. doi: 10.3390/sports13110376.
Authors: Krisztián Havanecz, Sándor Sáfár, Csaba Bartha, Bence Kopper, Tamás Horváth, Péter János Tóth, Gabriella P Szabó, Zoltán Szalánczi, Gábor Géczi
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12656065/pdf/sports-13-00376.pdf
Summary: Heart rate (HR) monitoring is a practical method for assessing internal load (IL). However, it remains unclear for which age group HR would be an appropriate predictor of IL considering the relationship with external load (EL). Thus, this study aims to evaluate the relevance and applicability of HR monitoring by exploring the relationship between EL and IL among U16 soccer players. EL was measured using global positioning system (GPS) data, while IL was assessed through training impulse (TRIMP), Edward’s TRIMP, HR exertion, rate of perceived exertion (RPE), and session-RPE (s-RPE). Nineteen (N = 19) male footballers from an elite football academy participated, with data collected from 50 training sessions and 11 matches. In the analysis of the training sessions, TRIMP demonstrated a near-perfect correlation with total distance (TD) (p < 0.001), and eTRIMP correlated strongly with TD (r = 0.82) and player load (r = 0.79). HR exertion also correlated significantly with TD, medium-speed running, decelerations, inertial movement analysis (IMA) events, and player load (p < 0.001). In matches, a large correlation was observed between TRIMP and TD (r = 0.73), while the strongest correlation was between RPE and s-RPE with TD and PL (p < 0.001). Furthermore, TD emerged as the best GPS-derived predictor of both TRIMP and HR exertion in training contexts. These findings provide evidence for the validity and usability of heart rate-based and RPE-based measures to indicate IL in U16 soccer players. Future research should focus on contextual factors in exploring the relationship between EL and IL.
9 Cutting-Edge Research on Physical Fitness Profile in Soccer Players
Reference: Sports (Basel). 2025 Oct 29;13(11):372. doi: 10.3390/sports13110372.
Author: Yiannis Michailidis
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12656156/pdf/sports-13-00372.pdf
10 AI in Bundesliga match analysis-expected possession value (EPV) vs. expected goals (xG) to predict match outcomes in soccer
Reference: Front Sports Act Living. 2025 Nov 10:7:1713852. doi: 10.3389/fspor.2025.1713852. eCollection 2025.
Authors: Leander Forcher, Leon Forcher, Alexander Woll, Stefan Altmann
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12640942/pdf/fspor-07-1713852.pdf
Summary: With an increasing number of key performance indicators (KPIs) in soccer analytics, it is key to identify the most valuable KPIs. One approach to define a KPI’s value is to assess its ability to predict match outcomes and future performance. Therefore, this study aims to compare the effectiveness of expected goals (xG) and expected possession value (EPV) in predicting match outcomes in both pre-match and post-match scenarios. Event and tracking data of three Bundesliga seasons (2022/23, 2023/24, & 2024/25) were used to develop four distinct match outcome prediction approaches: xG & EPV pre-match (using features including the last three match performances of teams & contextual factors) and xG & EPV post-match (using xG and EPV performances of the played match). The xG post-match prediction showed the best performance in predicting match outcomes (xG post-match: RPS = 0.148, Accuracy = 0.656; EPV post-match: RPS = 0.191, Accuracy = 0.596). In pre-match scenarios EPV showed higher prediction performance (RPS = 0.194, Accuracy = 0.583) compared to xG (RPS = 0.199, Accuracy = 0.556). Accordingly, xG holds more valuable performance information on the offensive performance of a team in post-match scenarios. In contrast, the EPV pre-match prediction showed powerful results in predicting future match outcomes and thereby showcased the predictiveness of EPV.
11 Determinants of agility across biological maturation status in soccer players
Reference: BMC Sports Sci Med Rehabil. 2025 Nov 25;17(1):355. doi: 10.1186/s13102-025-01424-8.
Authors: Ito Hironaga, Hirayama Kuniaki, Naito Yuto, Akama Takao
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12648829/pdf/13102_2025_Article_1424.pdf
Summary: Biological maturation alters the trajectories of physical capacities and may influence both the determinants of agility and agility itself. We aimed to examine the influence of biological maturation on agility across maturation phases and identify key determinants of agility in youth soccer players. Sixty-three players were classified into Pre-, Circa-, and Post-peak height velocity (PHV) groups based on biological maturation. Agility was assessed, and related factors were evaluated using various tests. Reaction time at the start of reactive shuttle test (RST) was measured, and the change of direction (COD) deficit was calculated as the difference between pro-agility and sprint times. RST time significantly decreased from Pre- to Circa-PHV (p < 0.05, d = – 2.75). In Pre-PHV, reaction time was the primary predictor of RST (p < 0.05, β = 0.69) and improved substantially (p < 0.05, d = – 0.97). In Circa-PHV, squat jump performance became the key predictor (p < 0.05, β = -0.26) and improved from Pre- to Circa-PHV (p < 0.05, d = 1.84). However, in Post-PHV, predictor contributions diminished, and RST time remained unchanged despite improvements in all factors except COD deficit. The COD deficit, consistently identified as a predictor, was longest in Post-PHV, indicating its increasing influence with maturation. These findings suggest that the influence of biological maturation on agility is most pronounced between Pre- and Circa-PHV, primarily driven by reaction time and lower limb power. At Post-PHV, factors beyond cognitive and physical abilities may influence agility. Reducing COD deficit during maturation may be critical for improving agility.
12 Effects of the FIFA 11 + Program on Physical Fitness in Youth and Adult Soccer Players: A Systematic Review and Meta-analysis
Reference: Sports Med. 2025 Nov 25. doi: 10.1007/s40279-025-02346-8. Online ahead of print.
Authors: Ibnu Noufal Kambitta Valappil, Karuppasamy Govindasamy, Gavoutamane Vasanthi, Masilamani Elayaraja, Cain C T Clark, Koulla Parpa, Borko Katanic, Hüseyin Şahin Uysal, Hassane Zouhal, Urs Granacher
Download link: https://link.springer.com/content/pdf/10.1007/s40279-025-02346-8.pdf
Summary: Soccer is a high-intensity sport that requires high levels of physical fitness, including balance, change of direction (CoD), speed and power. The FIFA 11 + program has been widely promoted to enhance physical fitness and reduce injury occurrence. This meta-analysis set out to examine how the FIFA 11 + program, implemented as a warm-up versus conventional warm-up (soccer-specific and alternative warm-ups), impacts physical fitness attributes in youth and adult soccer players. After a priori defined inclusion and exclusion criteria, 17 intervention studies with 611 male and female soccer players (Tier 2-4) aged 9-29 years were eligible to be included. The FIFA 11 + program implemented in the warm-up was contrasted with conventional warm-up programs (control) on outcome measures such as dynamic balance, CoD speed, linear sprint and proxies of muscle power (vertical jump height). The influence of potential moderators (e.g., training duration, frequency, session duration, age, sex, training and performance calibre) on study outcome measures was examined using subgroup analyses with the median split method. Findings demonstrated small-to-moderate improvements in favour of FIFA 11 + compared with conventional warm-ups on dynamic balance (small standardized mean differences [SMDs] = 0.37, p < 0.001, heterogeneity [I2] = 7), CoD speed (moderate SMDs = – 0.65, p = 0.005, I2 = 84), and vertical jump height (small SMDs = 0.56, p < 0.001, I2 = 71). Results from the sub-analyses showed that, for dynamic balance, shorter training durations (< 9 weeks) produced larger effects than longer durations (≥ 9 weeks) (SMDs = 0.62 versus SMDs = 0.17). For vertical jump height, < 9 weeks also yielded greater improvements (SMDs = 0.79 versus SMDs = 0.26). In terms of weekly training frequency, ≥ 3 sessions/week elicited larger gains in change-of-direction speed (SMDs = – 1.05 versus SMDs = – 0.12) and vertical jump height (SMDs = 0.73 versus SMDs = 0.01) compared with < 3 sessions/week. Regarding participant characteristics, players aged ≥ 18 years showed greater improvements than those < 18 years in change-of-direction speed (SMDs = – 1.45 versus SMDs = – 0.06) and vertical jump height (SMDs = 0.64 versus SMDs = 0.22). For sex differences, males experienced greater benefits than females in change-of-direction speed (SMDs = – 0.79 versus SMDs = – 0.04) and vertical jump height (SMDs = 0.54 versus SMDs = 0.09). Finally, higher-level players (≥ tier 3) demonstrated greater improvements in vertical jump height than lower-tier players (< Tier 3) (SMDs = 0.75 versus SMDs = 0.01). The observed benefits were statistically significant but generally of small-to-moderate magnitude and affected by study heterogeneity and program implementation differences. Most studies included male participants, limiting generalizability to female and underrepresented populations. Several studies also lacked rigorous methodological design, particularly in allocation, concealment and blinding. Reporting of training and demographic variables was often incomplete. These limitations highlight the necessity for rigorously designed, low-bias randomized controlled trials with standardized implementation of the FIFA 11 + program and thorough reporting to enhance the reliability of causal conclusions and improve clinical interpretation. The FIFA 11 + program was more effective than conventional soccer warm-up programs to enhance soccer players‘ physical fitness (i.e., dynamic balance, CoD speed, vertical jump height). A shorter training duration (< 9 weeks) and more weekly training sessions (≥ 3 sessions/week) induced larger performance effects. FIFA 11 + was more effective in older (≥ 18 years) and male players and in players of higher performance calibre (≥ Tier 3). These findings underscore the versatility of the FIFA 11 + program to improve soccer players‘ physical fitness, supporting its integration into the warm-up of regular soccer training sessions.
13 Epigenetic signatures, age acceleration, and injury risk in elite female and male soccer players
Reference: Sci Rep. 2025 Nov 25;15(1):41826. doi: 10.1038/s41598-025-25784-w.
Authors: Raúl F Pérez, Jon Lecumberri-Arteta, Marta Kulis, Teresa Botta-Orfila, Aina Rodríguez-Vilarrupla, Xavier Yanguas, Eva Ferrer, Gil Rodas, Jose I Martin-Subero
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12647692/pdf/41598_2025_Article_25784.pdf
Summary: Physical activity has been extensively associated with epigenetic modifications. However, the potential contribution of DNA methylation patterns to sports injury susceptibility remains largely unexplored, particularly among high-performance athletes. Since methylation regulates genes involved in inflammation, tissue repair, and musculoskeletal function, altered methylation profiles may influence injury risk. Moreover, epigenetic clocks are increasingly used to assess vulnerability to clinical phenotypes, as accelerated epigenetic aging has been linked to various diseases. Here, we studied the DNA methylome of peripheral blood cells in 74 elite female and male soccer players with extensive non-contact injury follow-up. We aimed to explore alterations associated with increased injury risk and to describe the dynamics of epigenetic age acceleration in this group. Although DNA methylomes between players with higher and lower injury risk were overall similar, we identified 1081 differentially methylated CpGs sites that partly affected genes involved in skeletal muscle functions. We also estimated epigenetic age using eight clocks but found no association with injuries. However, male athletes displayed higher epigenetic age acceleration than females. Comparing the methylome of age-accelerated versus decelerated individuals revealed widespread changes across five clocks, strongly biased towards hypomethylation in age-accelerated players. Differential CpGs targeted genes enriched in extracellular matrix, cytoskeletal and collagen-related functions. Overall, this study suggests a link between DNA methylation and non-contact injuries in elite soccer players and shows that epigenetic age acceleration, although unrelated to injuries, is associated with widespread hypomethylation.
14 Effects of virtual reality-based training for soccer players on anticipatory brain functions and cognitive skills
Reference: Biol Psychol. 2025 Nov 23:202:109168. doi: 10.1016/j.biopsycho.2025.109168. Online ahead of print.
Authors: Andrea Casella, Camilla Panacci, Merve Aydin, Luca Boccacci, Giulio Lodi, Benjamin Greenhough, Michael Parsons, Francesco Di Russo
Download link: https://pdf.sciencedirectassets.com/271293/1-s2.0-S0301051125X00090/1-s2.0-S0301051125001863/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEIP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJIMEYCIQC8N60Ge7L1UrxeD0Oos4yU46RJu%2BQlwzyIDLImc6nGKQIhAOckuUhZMg9NyWzYqW7Qpc89%2BAPkG%2BUF6hQIgLE%2Bi8YwKrIFCEwQBRoMMDU5MDAzNTQ2ODY1IgznOE978dK2zQ28TKcqjwWxgfDHZKZWf2OQgsZX7Gl7CgTyiuc6bq%2F2h6gOng6MrS1%2B83FCpfKwHJl86jhoeS%2FOwoZlephWIXorA1zJy%2FBdXAcs6y3ec%2FJYRzX5%2BifovLCM8efwHpQ6ELLT84jB7htfAnJjMEFz4C%2FCZz1Wehp0OhCUETLl%2FMXKnro94dC36MkWdaT7gVY9FxQvNK40X1nsnrSw1aGBDwEbqGk1tGc0e7DXSsElPuYfBZk%2Fu%2F4pesJmd2p5K0HDphY5xSJpg5gw4cIHPVSsir6T5DK148pmm2PsjFa6EsZdi8igDu2mSVMLHnF9bUR%2FycIRwcDZMBWUwY6M5LRa03eBIWBcj50SOYCfdEtgGiIBEAFPWMXRbY83YLeMxY6S9xY7r8ZrnIO4fjKc2LIqJWFhjfNVvTWZpKX4YloIex%2F%2F6BY3Rl7xg2%2FpeAGAcNV%2FzD3eWcz46JGVkjBb%2BaoW7t7NKRnKYSfDFAA%2BcUFafaobLJPnYBXvH79RE2VRMgNwYOpoq0vZ3ryZlqArlS1NhIrj%2Byp%2BaCcXqYQ7%2FCVzQ6LrpdwtGd3%2BKQ9s0N8MsHw2LUQbofEzk9QPjiSbOW%2FawF9RdWYtLvXvdjL9YQdlXKyH%2FrkIBpNj2%2BeHTk69b%2BwlWGBhDI7Y138mprvpONUJqOK6FZCL%2FAdk2jd5WtYHd73itIcxqWtoScSFsLV0fFtE4miwvOHrEjrUUAsK8RKjcKUMibaN00U0%2BjLMo7WmqsMiu%2B4OQ%2B9PgIcV0Aq%2FFcQ%2BBxZemYWDKdNGY%2Bf4vffmM%2FZLm2D2aa7ZARWPkTgHf9cQeBTTqTXoK1tHEmuAO7YKwmhDHdC4DeS6HLmH1Xknf8pUwAqqoOUmvTIarrlXG0Aa7dsTvAGbMKSux8kGOrABcAZyG%2F24zheHpHZPnjBgC%2FKEwHk8%2ByK4viqMTsi73O7TxTip4pEwxO4WGDN2vVhaDImQ5O4TjV%2FPSqNJQD64L%2FN7kbfHye7%2B4Te%2ByWX3rUuBsXGW2%2B6BxTuM6bvNMGRdg0IvJfMIm2J2JMDa%2BHyKj76HJwdwB0kWySW746ocQRrappkBqWouBarakNiWT6tknuZs2VxDe2ECkCi%2BcUWgy8%2Fegu9J9OnMIQnqRUARiBI%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20251204T193333Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYUWKYDYMC%2F20251204%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=59d4d887ab595c70396fc3489b7464c8671a2facb0f357abfa775b9f80773977&hash=db5fb9562a5f766957e656223cfa3515009a7c90b2eba260bb2961d77104774f&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0301051125001863&tid=spdf-649778e4-ad6a-45ad-a7ba-57ac54dc4f55&sid=ae44f91511dd6448f798dc282f4dc4e0b2b3gxrqa&type=client&tsoh=d3d3LnNjaWVuY2VkaXJlY3QuY29t&rh=d3d3LnNjaWVuY2VkaXJlY3QuY29t&ua=020356025e040703535f&rr=9a8dbc705f19d362&cc=de
Summary: The present study examines the impact of a sport-specific training program based on virtual reality (VR) in young semi-elitè soccer players on cognitive performance and on anticipatory brain functions using the event-related potential (ERP) method. In this randomized control trial, the participants were divided into two groups: a control group, which followed a standard soccer training program, and an experimental group, which followed the same training but underwent an additional VR training session once a week. Results indicated that after eight weeks of training, the experimental group only showed a notable enhancement of anticipatory brain activity in the prefrontal cortex as evidenced by a 40 % increase in the prefrontal negativity (pN) ERP component. The motor preparatory activity in the premotor cortex indexed by the Bereitschaftspotential (BP) component was comparable between groups before the training and larger in the experimental group after it. Furthermore, the experimental group only showed enhanced cognitive performance improving response speed and accuracy in a discrimination response task. These findings indicate that using VR protocol in conventional soccer training may enhance cognitive anticipatory brain processing underlying top-down cognitive functions. This likely boosted cognitive performance. In conclusion, we confirmed the potential of immersive technologies to facilitate the integration of cognitive training in sports.
15 Eccentric Exercises Reduce Hamstring Strains in Elite Adult Male Soccer Players: An Updated Critically Appraised Topic
Reference: J Sport Rehabil. 2025 Nov 25:1-5. doi: 10.1123/jsr.2024-0411. Online ahead of print.
Authors: Lauren N Sheldon, Evyn Callahan, Josiah Thompson, Sungwan Kim, Emma Zuk, Neal R Glaviano
Summary: Hamstring strain injuries are a common injury in many sport settings, but are especially common in soccer. These injuries can cause an athlete to miss time from play. Prevention programs have been shown to reduce the risk of injury. What is the effect of eccentric exercises on hamstring strain prevention in adult male soccer players? Upon a search of the literature, 1 additional article was found to meet the inclusion criteria set by the initial critically appraised topic. This revised critically appraised topic supports the initial critically appraised topic findings that eccentric hamstring exercises are an effective intervention for reducing hamstring strain injuries in elite male soccer players. Clinicians should prescribe eccentric training to prevent initial hamstring strain injuries and prevent recurrent injuries.
16 Relationships and agreement between Yo-Yo intermittent recovery test level 1 performance and laboratory VO2max in adolescent male soccer players: roles of maturity status, playing position, and running economy
Reference: Ann Hum Biol. 2025 Dec;52(1):2566327. doi: 10.1080/03014460.2025.2566327. Epub 2025 Nov 25.
Authors: Yaohui Xu, Naidan Xu, Rou Wang, Weiming Li, Indy Man Kit Ho, Eric Tsz-Chun Poon, Weijun Liu, Haochong Liu
Download link: https://www.tandfonline.com/doi/epdf/10.1080/03014460.2025.2566327?needAccess=true
Summary: Accurate assessment of aerobic fitness is essential in youth soccer. The Yo-Yo Intermittent Recovery Test Level 1 (YYIR1) provides a practical estimate of maximal oxygen uptake (VO2max), but its agreement with laboratory values across maturity stages remains uncertain. To examine the relationship and agreement between YYIR1 performance and laboratory-measured VO2max in adolescent male soccer players, and to assess whether biological maturation, playing position, and running economy (RE) affect estimation consistency. Twenty-three players (13.7 ± 0.5 years) completed YYIR1 and laboratory treadmill tests (LTT). VO2max was measured during LTT and estimated from YYIR1 performance. Effects of biological maturation [pre-, circa-, post-peak height velocity (PHV)], position, and RE were analysed. YYIR1 underestimated VO2max by 5.2% versus LTT (p < 0.001) but showed strong correlation (r = 0.82). Bland-Altman analysis indicated acceptable agreement. Estimation consistency was higher in pre- and circa-PHV players, though subgroup sizes were small. Maturation, position, and RE had no significant effects. YYIR1 is strongly associated with laboratory VO2max but systematically underestimates it. Coaches may use YYIR1 distance to monitor intermittent endurance, while interpreting estimated VO2max with caution. Larger, maturity-balanced samples are needed to clarify subgroup differences and improve youth-specific prediction accuracy.
17 Match running performance in elite soccer: a comparison of team and individual performance across age categories
Reference: J Sports Med Phys Fitness. 2025 Nov 24. doi: 10.23736/S0022-4707.25.17085-0. Online ahead of print.
Authors: Oussama Kessouri, Walid Grine, Yacine Belfritas
Summary: Match running performance is crucial for evaluating physical demands in elite soccer, with potential differences across age categories. Understanding these differences is essential for optimizing the physical preparation and career progression of young players. This study aimed to compare match running performance among senior, under-20 (U20), and under-17 (U17) elite soccer teams. Data were collected from FIFA World Cup 2022, U20 World Cup, and U17 World Cup 2023 from the FIFA website. Running performance was assessed at both the team level and the individual level. Key performance variables included total distance covered (TD), distance across five running zones, sprints (SPR), high-speed runs (HSR), and maximum sprinting speed (MSS). Linear mixed model was used to compare performance across the three age groups. No significant differences between senior and U20 teams in most variables (all P>0.05) were observed, except for walking distance, which favored the senior teams in both team and individual performance (P<0.05). U20 teams covered greater distances in jogging and moderate speed running (MSR) (team performance), and jogging distance (individual performance) compared to senior teams (P<0.05). Senior and U20 teams generally outperformed U17 teams in most variables (P<0.05), except for walking distance, where U17 teams performed higher than U20 teams (P<0.001), with no significant differences between U17 and senior teams (P>0.05) for individual performance. Additionally, U17 teams showed similar performance to senior teams in jogging distance (team performance) (P>0.05). Senior and U20 teams consistently outperformed U17 teams in most variables, except for walking distance. These findings provide valuable insights into the physical demands of match play across age groups.
18 Uncovering the Latent Components of Physical Performance in Professional Soccer: Evidence from the Turkish First Division
Reference: J Funct Morphol Kinesiol. 2025 Nov 7;10(4):434. doi: 10.3390/jfmk10040434.
Authors: Spyridon Plakias, Dimitris Tsaopoulos, Themistoklis Tsatalas, Giannis Giakas
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12641997/pdf/jfmk-10-00434.pdf
Summary: Physical performance in soccer is usually described through isolated indicators such as total distance or sprint frequency, which may overlook the broader structure of match demands. This study aimed to identify the latent components of physical performance in professional soccer and to examine how they vary across playing positions. External load data were collected from 446 outfield players competing in the Turkish first division during the 2021-2022 season, using optical tracking technology. Distances covered at different speed thresholds and maximal speed were analyzed through principal component analysis. Factor scores were compared across positions using non-parametric tests. Three components of physical performance emerged: (1) moderate-intensity running (2-5.5 m/s, inverse to low-speed activity), (2) high-intensity running (>5.5 m/s), and (3) sprint capacity (maximal speed). Central midfielders recorded the highest values in moderate-intensity running, wingers and wing backs excelled in high-intensity running, while sprint capacity was most strongly associated with wingers. The findings provide a more integrated understanding of soccer’s physical demands, moving beyond single indicators to reveal broader performance dimensions. This framework can support coaches, analysts, and scouts in player profiling, training design, and rehabilitation planning, while emphasizing the need for position-specific physical preparation.
19 The Muscle-Bone Unit in Male Elite Soccer Players Aged 14-19
Reference: J Funct Morphol Kinesiol. 2025 Nov 5;10(4):432. doi: 10.3390/jfmk10040432.
Authors: Valentina Cavedon, Carlo Zancanaro, Chiara Milanese
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12641845/pdf/jfmk-10-00432.pdf
Summary: Muscle and bone show reciprocal interactions and are associated in a muscle-bone unit. The muscle-bone unit has been investigated to a very limited extent in soccer players. The objective of this work was to investigate in detail the muscle-bone unit in male youth elite soccer players. Bone mineral and lean mass were measured with dual-energy X-ray absorptiometry (DXA). The functional muscle-bone unit (fMBU) and the muscle-to-bone ratio (MBR) were calculated from the DXA output in a sample of players aged 14-19 (n = 193) playing in the youth squads of an Italian Serie A team. Statistically significant (p < 0.05) correlations were found between lean mass variables and bone mineral content and density, also after adjusting for age, body mass, stature, maturity, and ethnicity (White/Black). fMBU and MBR were statistically significantly associated with age, body mass, stature, maturity, and ethnicity. Linear regression showed that body lean mass was the strongest predictor for bone mineral content and density. Age was a statistically significant predictor for fMBU and MBR. Playing position did not show any statistically significant relationship with bone mineral content and density, as well as fMBU or MBR. Centiles for fMBU and MBR were calculated as a reference. This work is the first detailed characterization of the muscle-to-bone relationship in soccer players. It is expected to be of use for sport scientists and the wide community of sportsmen and professionals involved in soccer.
20 Hamstring Strain Injury Risk in Soccer: An Exploratory, Hypothesis-Generating Prediction Model
Reference: Muscles. 2025 Nov 4;4(4):50. doi: 10.3390/muscles4040050.
Authors: Afxentios Kekelekis, Rabiu Muazu Musa, Pantelis T Nikolaidis, Filipe Manuel Clemente, Eleftherios Kellis
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12641714/pdf/muscles-04-00050.pdf
Summary: Hamstring strain injuries (HSI) are common in soccer and remain challenging to predict, as traditional risk factors often fail to capture the multifactorial nature of injury susceptibility. This prospective cohort study aimed to develop and internally validate a machine learning-assisted logistic regression model for predicting hamstring injuries in amateur soccer players using preseason clinical and strength-related variables. A total of 120 male players were followed for one competitive season (30 weeks). Baseline predictors included age, body mass index, previous injury, and bilateral isometric hip and knee strength measured via handheld dynamometry. Twenty initial predictors were reduced to ten through symmetrical uncertainty feature ranking before training a logistic regression model with elastic-net regularization (training set: n = 83; test set: n = 37) using nested four-fold cross-validation. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC), calibration metrics, and confusion matrices. During follow-up, 21 players sustained at least one HSI (32 events; 28% reinjuries), yielding an events-per-variable ratio of 2.1, below ideal thresholds and suggesting possible overfitting. On the independent test set, the model achieved an accuracy of 64.9%, AUC of 0.68 (95% CI 0.52-0.84), calibration slope of 0.85, and intercept of -0.12, with a sensitivity of 60% and specificity of 65.6%. Dominant-leg hip abduction strength was the only statistically significant predictor (OR = 0.82, 95% CI 0.70-0.96), while permutation importance analyses identified previous hamstring injury as the most stable contributor to model performance. Neither age nor hamstring isometric strength demonstrated predictive value. Although model discrimination was moderate and calibration indicated mild overfitting, findings reinforce the prognostic relevance of prior injury and suggest that reduced hip abduction strength may serve as an emerging candidate marker. This study, classified as a TRIPOD Category 2 model (development without external validation), provides preliminary, hypothesis-generating evidence supporting the use of multivariate strength and history-based predictors in future, larger-scale injury prediction research.
21 The effect of 12 weeks of basic soccer training on violence tendency, psychological resilience, social anxiety in 12-14 years old children
Reference: Front Psychol. 2025 Oct 30:16:1693298. doi: 10.3389/fpsyg.2025.1693298. eCollection 2025.
Authors: Büşra Özcan, Baha Engin Çelikel, Ramazan Erdoǧan, Mustafa Karadaǧ, Volkan Aydoǧdu, Fatih Mehmet Uǧurlu, Eyüp Bozkurt, Mehmet Turan, Meryem Koçal, Serdar Orhan
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12631278/pdf/fpsyg-16-1693298.pdf
Summary: Regular exercise during childhood impacts not only physical development but also emotional stability, social adaptation, and behavioral control. Therefore, the present study aimed to examine the effects of a 12-week introductory football training programme on violent tendencies, psychological resilience, and social appearance anxiety in children aged 12-14. A randomized controlled design was used, with 40 children assigned to an experimental group (n = 20) or a control group (n = 20). The experimental group completed 60-min football sessions three times a week, while the control group did not participate in structured activity. The program included a 20-min warm-up, technical and tactical exercises, game-based activities, and a cool-down, targeting physical, technical, tactical, and psychosocial development. Data were collected using the VTS, PRS, and SAAS scales.Statistical analyses were performed using SPSS version 25 (IBM Corp., Armonk, NY, USA), with mixed-design ANOVA, significance set at p < 0.05, and effect sizes reported as partial eta-squared (ηp2). No significant difference was observed in violence tendency scores in the experimental group (p = 0.939). However, a decrease was observed in psychological resilience scores in comparison to pre-test values, and this decrease approached the threshold of significance with a medium effect size (p = 0.153, ηp2 = 0.053). This finding suggests that the intervention may have a limited effect on psychological resilience. While no significant change was detected in the social appearance anxiety variable in the experimental group (p = 0.120), a significant decrease in anxiety levels was observed in the control group (p = 0.029). This finding suggests that factors other than the experimental intervention may have been effective in the control group. In conclusion, the 12-week football training programme demonstrated no significant short-term effect on violent tendencies or social appearance concerns, but may have a temporary effect on psychological resilience. The findings indicate that the impact of sports participation on psychosocial development in children is multifaceted and contingent on individual differences.
22 Sprints, Decelerations and Turns Most Commonly Precede Goals in Soccer: Analysis of 6 FIFA World Cups
Reference: Eur J Sport Sci. 2025 Dec;25(12):e70085. doi: 10.1002/ejsc.70085.
Authors: Lorcan Daly, Patrick Caulfield, David Martínez-Hernández
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12640733/pdf/EJSC-25-e70085.pdf
Summary: This study investigated actions preceding goals in male and female players across 6 FIFA World Cups. This is the first longitudinal, multi-sex analysis of goal actions using world-class data, extending validity and findings beyond the current evidence base (domestic, single-sex studies). In total, 2995 actions preceding goals from open-play were analysed across the last 6 men’s‘ and women’s FIFA world cups (2014-2023) using the modified Bloomfield method. Additionally, possible longitudinal (tournament cycle), sex, and role-based (i.e., scorer vs. assister) differences were examined using Bayesian and chi-squared analyses. Linear advancing movements (≈41%), particularly sprinting, were the most prevalent actions leading to goals, followed by deceleration (≈22%) and turns (≈19%) (Cramer’s V = 0.27-0.38; p < 0.05). Longitudinal, between-sex and between-role (i.e., scorer vs. assister) differences were predominantly minimal for movement types (Bayes Factors [BF10] < 0.01; Cramer’s V = 0.02-0.06; p > 0.05). Sprinting preceded goals more prevalently for males (43.4%) and scorers (43.2%), when compared with females (39.0%) and assisters (39.1%), respectively (Cramer’s V = 0.04-0.10; p < 0.05). Female players performed significantly greater proportions of actions at high intensity versus males (53.0 vs. 47.9%; BF10 = 38.7; Cramer’s V = 0.369; p < 0.05), and the 2022/2023 cycle had lower proportion of actions at high intensity compared to earlier cycles (46.6% vs. 52.3%-52.5%; BF10 = 0.019; Cramer’s V = 0.06; p < 0.05). This analysis highlights the importance of sprinting, decelerating, and turning for goal-scoring. Therefore, enhancing players‘ physiological and mechanical reserves to undertake these actions, as and when required during match-play, appears prudent. Further, analysts/coaches may apply this information to identify decisive goal-scoring actions and design targeted training drills accordingly.
23 Use of SEM-PLS analysis to predict sports injuries in professional football players through warehouse technology data
Reference: Sci Rep. 2025 Nov 28. doi: 10.1038/s41598-025-30359-w. Online ahead of print.
Authors: Fan Cheng, Hisham Noori Hussain Al-Hashimy, Jinfang Yao
Download link: https://www.nature.com/articles/s41598-025-30359-w_reference.pdf
24 Improving women football tactics analysis by using extreme learning and accumulated optimization algorithm
Reference: Sci Rep. 2025 Nov 28. doi: 10.1038/s41598-025-30218-8. Online ahead of print.
Authors: Jun Li, Mohammad Khishe, Banar Fareed Ibrahim
Download link: https://www.nature.com/articles/s41598-025-30218-8_reference.pdf
Summary: The research will fill the existing gaps in the current approaches to the analysis of the strategies of women football by offering a new deep-learning framework and creating the Accumulated Chimp Optimization Algorithm (ACHOA). Traditional approaches like Deep Convolutional Neural Networks (DCNN) are very processing-intensive and thus they are not effective in real-time applications. Moreover, the random factor selection that is typical of the existing approaches involving the use of Deep Extreme Learning Machines (DELM) makes the reliability and accuracy of such models in terms of forecasting less than satisfactory. In order to overcome these deficiencies, we propose a new ACHOA-enhanced DELM model that enhances the performance of the model by making the parameters stable. In a way our method is a supplement to video recordings, as it makes use of the continuous frames to determine how effective a player is, how many skills may be estimated to be under the hood, and where he/she makes positional errors, which enables a more dramatically tactical goal that could not be reached before. One of the main contributions of this study is the ACHOA itself that enhances the reliability of the DELM model. The model has been trained and tested on video data from the 2021-2022 UEFA Women’s Champions League and the model has been validated using this real-world data. It achieved a classification accuracy of over 95%, and there was better agreement between the factors and the evaluations made by the experts. Further, the possibility of real-time monitoring helps to make tactical shifts, which enhances pre-game measures and develops performance metrics in women’s soccer.
25 Capturing the wider benefits from football participation: a social return on investment (SROI) evaluation of a community based football intervention
Reference: BMC Public Health. 2025 Nov 27;25(1):4177. doi: 10.1186/s12889-025-25288-2.
Authors: Steve Daly, Tom Egan, Paula Carroll, Gillian Curran, Michael Harrison, Aisling McGrath, Laura Finnegan, Noel Richardson, Peter Krustrup
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12659226/pdf/12889_2025_Article_25288.pdf
Summary: Gendered approaches to engage men are recommended for health promotion, with community settings, that involve physical activity and specifically football being frequently employed. One such football initiative, Football Cooperative (FC), has operated in Ireland since 2017 bringing men together twice a week for ‚pick up‘ games. However, there is limited understanding of the reach or impact of the initiative, and an economic evaluation would inform policy decisions around the allocation of scarce resources within the public health and community-based setting. A localised version of cost-benefit analysis – Social Return on Investment (SROI) – was employed to assess this initiative. This involved a study of one site in 2021/2022 without a control group, and a range of data (self-reported and anthropometric) were collected at baseline, 3, 6 and 12 months. One hundred and twenty-three Participants (P) were available for this study, which also gathered data from other stakeholders, Significant Others (SO), Community Partners (CP) and Volunteer Coordinators (VC). Outcomes were validated with all stakeholders and measured by the stakeholders. Input costs were also gathered, and a comparison of outcomes with costs showed an SROI ratio of €17.60 in benefit for every €1 invested in the single FC site. Additional analysis exploring the implications of scaling this initiative to ten sites proposes an SROI ratio of €9.46 for every €1 invested. The computed SROI ratios for a single site and for ten sites compare favourably with those of other health initiatives particularly other football and community based SROI evaluations. Furthermore, this study quantifies the benefits of football participation from a mental health and social perspective in addition to physical benefits, and it also highlights the benefits of football participation to other stakeholders such as participants‘ family (SO). Future research could expand on this study and investigate the impact of future football initiatives in diverse locations with larger cohorts.
26 Impact of the ‚FUNBALL‘ Programme on Severe Injuries Among Young Male Football Players: A Secondary Analysis from a Cluster-Randomised Controlled Trial
Reference: Sports Med Open. 2025 Nov 27;11(1):151. doi: 10.1186/s40798-025-00945-3.
Authors: Rilind Obërtinca, Rina Meha, Ilir Hoxha, Bujar Shabani, Tim Meyer, Karen Aus der Fünten
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12660612/pdf/40798_2025_Article_945.pdf
Summary: ‚FUNBALL‘ is a new multi-component exercise-based injury prevention programme designed specifically for youth football players. Its efficacy in reducing the overall number of injuries has been previously reported. The aim of this study was to investigate the effects of the ‚FUNBALL‘ programme in reducing the incidence of severe injuries (absence from training/match ≥ 28 days) in young male football players. 55 football teams from Kosovo, 21 in the Under-15, 22 in the Under-17, and 12 in the Under-19 age groups, were cluster-randomly assigned to the intervention or the control group. The intervention group performed the ‚FUNBALL‘ programme after their usual warm-up at least twice per week. The control group followed their usual training routine. Teams were followed for one football season (August 2021-May 2022). The outcome for the present analysis is severe injuries. The overall incidence rate (IR) was 0.31/1000 football hours in the intervention group and 0.62/1000 football hours in the control group. Players in the age group of the Under-19s sustained the highest number of severe injuries (IR 0.77/1000 football hours). The overall number of severe injuries was significantly reduced by 49% (incidence rate ratio (IRR) 0.51; 95% CI 0.28-0.91; P = 0.02), with a 63% reduction in those that occurred during training (IRR 0.37; 95% CI 0.15-0.87; P = 0.02). When analyzed by age group, only the Under-17s showed a significant reduction of 76% (IRR 0.24; 95% CI 0.06-0.82; P = 0.02). The low number of subgroup injuries prevented statistical significance. However, a promising protective effect was observed. Severe knee injuries were reduced by 62%. By injury type, sprains or ligament injuries were reduced by 67%, and meniscus or cartilage lesions by 58%. Overuse/growth-related injuries were reduced substantially by 85%. The ‚FUNBALL‘ programme showed a large efficacy in reducing the incidence of severe injuries in young male football players. Considering that these injuries cause the longest absence from football, it is recommended to implement the programme at least twice per week to exert a preventative effect.
27 The effect of organizational differentiation in football training on young football players
Reference: Front Psychol. 2025 Nov 11:16:1565594. doi: 10.3389/fpsyg.2025.1565594. eCollection 2025.
Authors: Olav Størdal, Terje Dalen, Pål Lagestad
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12643876/pdf/fpsyg-16-1565594.pdf
Summary: The Norwegian Football Federation (NFF) has a primary goal of providing children and adolescents with a good football offer and positive football experiences, where differentiation is one way to achieve this. The aim of the present study was to investigate the effect organizational differentiation has on psychological and physical variables in 13-14-year-old male football players. An intervention study with an experimental randomized crossover design was used, where players from three football teams participated in two differentiated training sessions and two non-differentiated training sessions. The four training sessions had the same exercises, with the same coach. The physical measurements involved heart rate, number of accelerations, number of sprints and total distance covered measured by Polar Team Pro GPS, while the psychological variables measured in a questionnaire was wellbeing, mastery, joy, satisfaction and experienced development. Wilcoxon nonparametric tests were used to compare the results from differentiated and non-differentiated sessions. The results showed that players with upper-level skills (UG) experienced significantly higher enjoyment, satisfaction, and development in differentiated training compared to non-differentiated training and preferred differentiated training. No significant differences were observed in psychological variables between differentiated and non-differentiated training among lower-group players. Furthermore, all players had more accelerations and increased their total distance covered during differentiated training compared to non-differentiated training regardless of group. Finally, players in UG had a higher average heart rate during the entire session, as well as in the sub-exercises SSG, 2v2+1 games, and rondo 4v1. The results suggest that organizational differentiation positively affects young players‘ physical variables, especially players with upper-level skills. Organizational differentiation also positively affects psychological variables of young players with upper-level skills. However, careful consideration should be given to the potential long-term consequences of differentiation for lower-skilled players, especially regarding social belonging and self-perception.
28 Harmonisation and implementation of sports-related concussion guidelines in European youth football: the REFORM Erasmus+ project
Reference: BMJ Open Sport Exerc Med. 2025 Nov 16;11(4):e002928. doi: 10.1136/bmjsem-2025-002928. eCollection 2025.
Authors: Giulia Gorgoni, Gabriel Monthuley, Thor Einar Andersen, Nora Kümmeth-Gangel, Ivana Pavlinac Dodig, Demet Dinç, Tim Meyer, Anna Nordström
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12645643/pdf/bmjsem-11-4.pdf
Summary: Sports-related concussions (SRCs) are frequently under-reported in youth sports, especially football, due to limited awareness, inconsistent reporting practices and a lack of medical personnel at the grassroots level. Concussion management protocols vary widely across regions, highlighting the need for a standardised approach. This study aims to harmonise SRC education and management practices in European youth football through an interdisciplinary collaboration involving football associations, healthcare professionals and academic institutions from Norway, Germany, Croatia and Turkey. The project will develop and implement educational resources (eg, toolkits, workshops and a Massive Open Online Course (MOOC)) targeted at coaches, players, parents, referees and medical personnel. Using a participatory action research design guided by the Logical Framework Approach, the project will develop, pilot and evaluate concussion education tools across diverse football contexts. Surveys, focus groups and participatory workshops will be used to assess changes in knowledge, attitudes and behaviours. Quantitative data will be analysed using descriptive statistics, while qualitative data from focus groups and interviews will undergo reflexive thematic analysis. Engagement metrics from MOOCs and toolkits will also be tracked. Ethics approval has been obtained in all participating countries. Informed consent (or parental consent for minors) will be secured for all participants. Dissemination will occur through UEFA, national football associations and complemented by social media outreach and presentations at sports conferences. The project is expected to enhance stakeholder awareness, improve concussion management protocols and provide a scalable model for concussion education in grassroots football across Europe.
29 Machine Learning-Based Prediction of Muscle Injury Risk in Professional Football: A Four-Year Longitudinal Study
Reference: J Clin Med. 2025 Nov 13;14(22):8039. doi: 10.3390/jcm14228039.
Authors: Francisco Martins, Hugo Sarmento, Élvio Rúbio Gouveia, Paulo Saveca, Krzysztof Przednowek
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC12653399/pdf/jcm-14-08039.pdf
Summary: Professional football requires more attention in planning work regimens that balance players‘ sports performance optimization and reduce their injury probability. Machine learning applied to sports science has focused on predicting these events and identifying their risk factors. Our study aims to (i) analyze the differences between injury incidence during training and matches and (ii) build and classify different predictive models of risk based on players‘ internal and external loads across four sports seasons. This investigation involved 96 male football players (26.2 ± 4.2 years; 181.1 ± 6.1 cm; 74.5 ± 7.1 kg) representing a single professional football club across four analyzed seasons. The research was designed according to three methodological sets of assessments: (i) average season performance, (ii) two weeks‘ performance before the event, and (iii) four weeks‘ performance before the event. We applied machine learning classification methods to build and classify different predictive injury risk models for each dataset. The dependent variable is categorical, representing the occurrence of a time-loss muscle injury (N = 97). The independent variables include players‘ information and external (GPS-derived) and internal (RPE) workload variables. The Kstar classifier with the four-week window dataset achieved the best predictive performance, presenting an Area Under the Precision-Recall Curve (AUC-PR) of 83% and a balanced accuracy of 72%. In practical terms, this methodology provides technical staff with more reliable data to inform modifications to playing and training regimens. Future research should focus on understanding the technical staff’s qualitative vision of predictive models‘ in-field applicability.