Latest research in football – week 42 – 2026

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 Upper-Body Isometric Strength Qualities Are Associated With Faster High-Intensity Running Performances in Professional Soccer Players: A Cross-Sectional Study

Reference: J Strength Cond Res. 2026 Aug 21. doi: 10.1519/JSC.0000000000005652. Online ahead of print.
Authors: Ivan Curovic, Lazar Toskic, Milan Markovic, Jill Alexander, Dejan Suzovic, David Grecic, Damian J Harper
Summary: Despite being highlighted as potentially important, the relationship between greater upper-body (UB) strength and lower-body-dominant high-intensity actions (HIA) in professional soccer players remains unknown. The aim of this study was to examine the associations between relative UB isometric strength qualities and HIA [i.e., sprinting, repeated sprint ability (RSA), change of direction (COD), vertical jumping] while controlling for leg power influence in 63 male professional players. Statistical significance was set at p ≤ 0.05. Results identified that handgrip strength (HGS), particularly rate of force development (RFD), demonstrated significant large correlations with faster 30-m sprints (r ≈ -0.52, p < 0.001) and RSA (r ≈ -0.55, p < 0.001). Upper-body maximal strength capacity (push-pull composite score) exhibited significant moderate correlations with faster RSA (r = -0.36, p = 0.004) and COD 505 test (r = -0.30, p = 0.019). Hierarchical regression analysis showed that, after controlling for leg power, UB strength accounted for an additional 12.1% of the variance in RSA performance (ΔR2 = 0.121, p = 0.004), while HGS added a further 12.4% (ΔR2 = 0.124, p = 0.002), with the full model explaining 29.3% of total variance. In conclusion, greater relative UB strength appears to be linked to superior high-intensity running performances in professional soccer players, especially during RSA tasks. Future research should investigate the effects of UB strength training through longitudinal interventions and further explore the role of UB-derived RFD metrics for HIA while accounting for horizontal lower-body force-generating capacities.

#2 Impact of Weekly Workload Distribution on Performance in Male Soccer Players Across Competitive Levels-Scientific Hypothesis or Empirical Evidence: A Systematic Review

Reference: J Strength Cond Res. 2026 Aug 21. doi: 10.1519/JSC.0000000000005627. Online ahead of print.
Authors: Guillaume Lafrance, Gregory Dupont, Said Ahmaidi, Abd-Elbasset Abaïdia
Summary: This systematic review aimed to analyze weekly workload distribution patterns in male soccer and examine their potential effects on performance outcomes. A systematic search was conducted using PubMed, ScienceDirect, and Web of Science databases until December 2025. The analysis followed a 2-step approach: first, characterizing weekly workload distribution patterns within the microcycle, and second, examining available evidence on the potential effects of these distribution patterns on physical performance outcomes. Methodological quality was assessed using the Newcastle-Ottawa Scale. Forty-three studies met the inclusion criteria, with a moderate methodological quality score (5.09 ± 0.84/9). The synthesis identified a consistent weekly periodization model characterized by 3 phases: postmatch recovery (MD+1/MD+2), peak load distribution (MD-4/MD-3), and prematch tapering (MD-2/MD-1). Although this framework was common across teams, substantial observational differences in its practical implementation were reported. Regarding performance outcomes, only 2 studies (4.6%) examined the direct impact of load distribution through specific performance tests, providing limited evidence to establish clear relationships between training load patterns and physical performance. In conclusion, despite a common weekly framework, substantial differences in practical implementation across studies exist, and there is a critical lack of evidence regarding the impact of different load distribution strategies on performance outcomes. Future research should prioritize examining the relationship between weekly load distribution and performance to establish evidence-based recommendations for practitioners.

#3 Active reperfusion for enhancing high-intensity intermittent performance in soccer players

Reference: Int J Sports Med. 2026 Aug 20. doi: 10.1055/a-2934-8226. Online ahead of print.
Authors: Izabela A Santos, Enrico F Puggina, Donizete C X de Oliveira, Gustavo R Mota
Summary: This study aimed to determine whether active ischemic preconditioning, incorporating exercise during the reperfusion phases, would enhance Yo-Yo Intermittent Recovery Test Level 2 performance in soccer players. Seventeen male amateur soccer players (24.0±1.8 y) completed three different preconditioning sessions before the Yo-Yo Intermittent Recovery Test Level 2. The ischemic preconditioning protocol consisted of three cycles of 4-minute occlusion (220 mm Hg), followed by 4-minute reperfusion (0 mm Hg) in both thighs (at rest). Active protocols were similar to ischemic preconditioning; however, during reperfusion, participants performed intermittent running (ischemic preconditioning+Yo-Yo Intermittent Recovery Test Level 2) or three-repetition maximum squat repetitions (ischemic preconditioning+SQUAT). We assessed countermovement jump and Yo-Yo Intermittent Recovery Test Level 2 performance, heart rate, muscle oxygen saturation, blood lactate, rating of perceived exertion, and session-rating of perceived exertion. Ischemic preconditioning+SQUAT resulted in a greater Yo-Yo Intermittent Recovery Test Level 2 distance compared to ischemic preconditioning (p=0.02 and effect size=0.3) and ischemic preconditioning+YOYO (p=0.01, effect size=0.2). Countermovement jump performance was affected by condition (p<0.01), with ischemic preconditioning+YOYO presenting higher values compared with ischemic preconditioning (effect size=1.1), although no time effect was observed. No significant differences were observed for muscle oxygen saturation (p=0.09), blood lactate (p=0.32), and rating of perceived exertion/session-rating of perceived exertion (p=0.96); however, the mean heart rate was higher with active reperfusion conditions than ischemic preconditioning. Active reperfusion combined with heavy squat exercise slightly improved high-intensity intermittent running performance in soccer players, while also eliciting higher heart rate responses, which should be considered during training monitoring.

#4 Cortical dynamics of adolescent and adult semi-skilled soccer players during execution of the passing skill: An EEG study

Reference: J Sports Sci. 2026 Aug 18:1-14. doi: 10.1080/02640414.2026.2719312. Online ahead of print.
Authors: Narges Mohammadkhani, Ehsan Zareian, Alireza Farsi, Saeed Alboghebeish, Fatemeh Keshvari
Summary: This study examined age-related differences in cortical oscillatory activity during goal-directed soccer passing in adolescent and adult semi-skilled male players. Thirty participants, including 15 adolescents and 15 adults, performed successful instep passes over 3, 5, and 7 m while wireless EEG was recorded. Relative theta, alpha, and beta power were calculated across six scalp regions of interest and analyzed using separate 2 × 6 × 3 mixed-design ANOVAs. Theta relative power showed significant main effects of group, region, and pass distance, with adolescents exhibiting higher overall theta activity than adults. Alpha relative power also showed significant main effects of group, region, and pass distance, whereas group-related interaction effects were not significant. Beta relative power showed a significant main effect of region and a group × region interaction, but no overall group or pass-distance effect. These findings indicate age-group differences in cortical oscillatory activity during soccer passing, expressed mainly in theta and alpha activity, whereas beta activity was more closely related to regional sensorimotor organization. Overall, adolescent players may require greater attentional and regulatory cortical engagement during goal-directed passing.

#5 Two-thirds return but performance suffers: ACL reconstruction outcomes across elite European women’s soccer leagues

Reference: J Exp Orthop. 2026 Aug 17;13(3):e70888. doi: 10.1002/jeo2.70888. eCollection 2026 Jul.
Authors: Haneef Khan, Forest Rodriguez, Amina Khan, Ashley Rosenberg, Stephen Marcaccio
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC13479473/pdf/JEO2-13-e70888.pdf
Summary: The aim was to analyse return-to-play (RTP) rates, timing and performance outcomes following anterior cruciate ligament (ACL) reconstruction (ACLR) in elite European women’s soccer players across the top five leagues. We reviewed ACL injuries sustained by female professional soccer players across the Bundesliga, Women’s Super League, Primera División Femenina, Serie A Women and Première Ligue between 2007 and 2025. Players were included if they had a confirmed ACL injury requiring ACLR and one season of performance data pre- and post-injury. Players were excluded if the injury occurred during their rookie season or after the 2023 season. Data were collected from Soccerdonna.de and Transfermarkt. A total of 242 ACL injuries in 206 unique players were included, with a median follow-up of 2.0 seasons (interquartile range [IQR]: 1.0-4.0). The cohort had a median age at injury of 22.7 years (IQR: 20.4-26.0; mean 23.4 ± 3.8 years). Of 242 injuries, 161 (66.8%) resulted in RTP. For those who returned, the median RTP time was 9.8 months (IQR: 7.9-11.4). Only 7 (5.1%) players achieved RTP before 6 months. In the first year following RTP, significant performance decreases were observed: games played (-47.4%, p < 0.001), total minutes (-57.8%, p < 0.001) and minutes per game (-24.4%, p < 0.001). Midfielders experienced the greatest decline in playing time (-41.2%, p < 0.001), while goalkeepers showed minimal change (-8.0%, p = 0.625). No significant age-related differences were observed. Median post-injury career length was 2.0 seasons (IQR: 2.0-4.0). A RTP rate of 66.8% was observed following ACLR in elite European women’s soccer; however, returning players faced significant performance decreases in the first year post-return, with notable position-specific variations. These reductions likely reflect a combination of injury-related recovery factors and team selection dynamics. Rehabilitation and RTP strategies should therefore integrate position-specific demands, realistic performance expectations and gradual reintegration plans, particularly for midfielders who demonstrated the greatest performance decline.

#6 Reliability, Validity, and Predictive Value of the Landing Error Scoring System in Soccer Players: A Systematic Review

Reference: Sports Health. 2026 Aug 17:19417381261463676. doi: 10.1177/19417381261463676. Online ahead of print.
Authors: Zongjun Li, Yunjiao Yang, Yuge Fu, Xuechuan Guo, Lixia Fan
Summary: Lower-limb injuries are common in soccer. The landing error scoring system (LESS) is used widely for field-based movement screening, yet its psychometric properties and prognostic value in soccer populations remain uncertain. The aim was to synthesize evidence on the reliability, validity, and prognostic utility of the LESS among soccer participants. PubMed, Web of Science, Cochrane Library, CNKI, and Wanfang were searched from inception to August 2025. Studies were included if they involved soccer participants and reported LESS-related reliability, validity, or prognostic outcomes. Modified versions of the LESS were included only when their scoring framework was clearly described and broadly comparable with the original tool. Two reviewers independently screened studies, extracted data, and assessed methodological quality using a modified Newcastle-Ottawa Scale. Reliability and validity outcomes, including intraclass correlation coefficients (ICCs) and agreement with 3-dimensional (3-D) motion analysis, were summarized descriptively. Prognostic metrics, including odds ratios (ORs) and area under the curve values, were extracted when available. When ≥2 comparable prospective cohorts were available, an exploratory random-effects meta-analysis was performed. A total of 10 studies met the inclusion criteria. In soccer settings, the LESS demonstrated excellent intra-rater reliability (ICC ≈ 0.90-0.95) and good inter-rater reliability (ICC ≈ 0.84-0.95), with item-dependent convergent validity versus 3-D kinematics. Evidence for prognostic utility was inconsistent across cohorts. Exploratory pooling of 2 comparable prospective studies showed that higher preseason LESS scores were associated with greater odds of subsequent lower-limb injury (pooled OR, 9.31; 95% CI, 3.11-27.91; I² = 0%). However, this pooled estimate should be interpreted cautiously because it was based on only 2 studies with variable injury definitions. The LESS is reliable and shows acceptable construct validity in soccer participants, but evidence for its prognostic utility remains inconsistent. It should not be interpreted as a stand-alone predictor of injury risk. Clinically, the LESS may serve as a low-cost, field-based assessment of landing movement quality within a broader multifactorial screening framework.

#7 Earlier strength recovery with partial-thickness versus full-thickness quadriceps tendon graft for anterior cruciate ligament reconstruction in competitive soccer players

Reference: Knee Surg Sports Traumatol Arthrosc. 2026 Aug 17. doi: 10.1002/ksa.70547. Online ahead of print.
Authors: Jose Luis Martin-Alguacil, Manuel Arroyo-Morales, Maria Lopez-Garzon et al.
Download link: https://esskajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ksa.70547
Summary: This study aimed to compare strength recovery, functional and clinical outcomes between full- and partial-thickness quadriceps tendon autografts for 12 months post-operatively and to examine the clinical implications of graft thickness in anterior cruciate ligament reconstruction among non-professional competitive soccer players. 42 non-professional competitive Spanish federal soccer players who underwent primary anterior cruciate ligament reconstruction using either full- or partial-thickness quadriceps tendon grafts were included in this retrospective cohort study. Both groups followed standardised surgical and rehabilitation protocols. Evaluations were assessed preoperatively and at 3, 6 and 12 months post-operatively, with the reinjury rates recorded at 24 months. Quadriceps index, measured by isokinetic dynamometry was the primary outcome. Hamstring index, extension and flexion peak torque, single leg hop test, patient-reported outcome measures (Lysholm and Cincinnati Knee Rating System scores) and reinjury rate were evaluated as secondary outcomes. Statistical analysis was performed using repeated-measures ANCOVA with a Bonferroni adjustment, and the significance level was set at 5%. During the first 6 months, faster recovery of quadriceps symmetry was observed in partial-thickness group compared to the full-thickness group at 300°/s (mean difference: -26.5, 95% confidence interval [CI] [-51.4, -1.7], p = 0.037), 180°/s (mean difference: -31.0, 95% CI [-56.0, -6.0], p = 0.017), and 60°/s (mean difference: -31.2, 95% CI [-55.4, -7.0], p = 0.013), as well as greater improvement in extension peak torque. No statistical differences (p > 0.05) remained between groups at 12 months, with both groups achieving similar recovery. Hop test and clinical outcomes improved significantly over time in both groups, without significant between-group differences (p > 0.05). Reinjury rate was similar between groups (p = 0.634). Earlier strength recovery was observed with partial-thickness graft after ACL reconstruction, highlighting the clinical relevance of graft choice in early rehabilitation in competitive soccer players.

#8 Training Load Variables in Elite Youth Soccer: Is a Data Reduction Approach Consistent Across Different Age Groups?

Reference: Int J Sports Physiol Perform. 2026 Aug 14:1-8. doi: 10.1123/ijspp.2025-0050. Online ahead of print.
Authors: Darragh Connolly, Sean Stolp, Ermanno Rampinini, Aaron J Coutts
Summary: A key issue for practitioners is the ability to handle the increased quantity of data provided by wearable microtechnology and the identification of which metrics provide actionable insights in players training responses. The aim of this study was to investigate the ability of principal component analysis (PCA) to reduce the number of variables assessed in a player monitoring program and verify the consistency of variables retained across different age groups of an elite youth soccer academy. A PCA was conducted to reduce the dimensionality of training and match data recorded by 145 players from Under 15 to Under 19 squads. The variables assessed included Global Positioning System metrics, heart rate measures, and players session rating of perceived exertion values (n = 82). Seven principal components were extracted for each age group, describing 67.6% to 68.7% of variability. Inconsistencies were observed in the number of variables retained (range: 24-28) and their loadings between the different age groups. These differences in metrics retained and strength of their contributions indicate that PCA outcomes cannot be generalized across the different age groups. General themes and constructs of load were observed across the 4 age groups, including measures of volume and intensity for both internal and external loads. The inconsistencies show that employing a PCA approach with a wide array of variables may not be practical for use in an applied environment, where the application of a conceptual framework can aid the selection process.

#9 Training Load Variables in Elite Youth Soccer: Is a Data Reduction Approach Consistent Across Different Age Groups?

#10 Plantarflexion and frontal-plane ankle strength are associated with dynamic balance in youth male soccer athletes: a cross-sectional study

Reference: BMC Sports Sci Med Rehabil. 2026 Feb 27;18(1):370. doi: 10.1186/s13102-026-01569-0.
Authors: Raphael Schmidt de Mesquita, Tamiris Beppler Martins, Bruno da Cruz Dorneles et al.
Download link: https://link.springer.com/content/pdf/10.1186/s13102-026-01569-0.pdf
Summary: Ankle strength is essential for dynamic stability and athletic performance. However, its specific relationship with commonly used functional tests remains underexplored in youth athletes. Understanding these associations may inform more targeted training approaches and injury prevention strategies. This study aimed to investigate whether isokinetic ankle strength is associated with performance in three widely used functional tests, the Modified Star Excursion Balance Test, the Side Hop Test, and the Weight-Bearing Lunge Test, in youth male soccer players. Twenty-six male soccer players (mean age: 18.56 ± 0.61 years) underwent isokinetic strength assessments, including plantarflexion, dorsiflexion, inversion, and eversion, and performed the Modified Star Excursion Balance Test, the Side Hop Test, and the Weight-Bearing Lunge Test. Limb symmetry was confirmed through paired t-tests, allowing the use of bilateral averages. Pearson correlation coefficients and Least Absolute Shrinkage and Selection Operator regression models were applied to examine associations and predictive capacity. Significant correlations were found between plantarflexion, inversion, and eversion torque and performance in the Modified Star Excursion Balance Test, with the strongest associations observed for the posteromedial, posterolateral, and composite scores (r = 0.70-0.81, p < 0.001). Performance in the Weight-Bearing Lunge Test was positively associated with plantarflexor torque (correlation coefficient = 0.54, p = 0.004), while dorsiflexor strength showed no significant correlation (p = 0.172). LASSO regression models retained plantarflexor torque (β = 0.078) and frontal-plane torques (inversion: β = 0.054; eversion: β = 0.028) as variables associated with the mSEBT composite score. For the Weight-Bearing Lunge Test, plantarflexor (β = 2.078) and dorsiflexor torque (β = – 0.463) were retained as variables associated with dorsiflexion angle. No strength variables were retained in the model explaining variance in Side Hop Test performance. Ankle strength, particularly in plantarflexion and frontal-plane movements, plays a key role in dynamic balance and mobility but appears to be less associated with agility-focused tasks such as the Side Hop Test. These findings support the incorporation of strength training targeting multiplanar ankle control and highlight the importance of neuromotor training to enhance agility in youth athletes.

#11 The Function of Religious Rituals in Psychological Coping and Motivational Meaning-Making Among Professional Football Players: Evidence from Turkey

Reference: J Relig Health. 2026 Aug 21. doi: 10.1007/s10943-026-02756-6. Online ahead of print.
Authors: Emre Uysal, Mehmet Haşim Akgül
Summary: This study investigates how professional football players in Turkey experience and interpret religious rituals in relation to motivational meaning-making and psychological coping. Employing an exploratory qualitative research design, data were collected through semi-structured interviews with 25 professional male football players competing in the Turkish Super League during the 2024-2025 season. Interviews were conducted in Turkish via online video-conferencing platforms and analyzed using thematic analysis. Participants described their religious rituals as active psychological coping mechanisms for managing performance anxiety, stress, and uncertainty inherent in elite sport, extending beyond mere expressions of faith. Specifically, they characterized these rituals as emotional regulators that fostered a sense of control, self-efficacy, and psychological readiness. Faith was also reported as a source of spiritual resilience, particularly during career crises such as injury and loss of form. A notable finding is that participants largely avoided institutional religious accessories, instead attributing personal significance to secular objects connected to meaningful relationships and life experiences. The accounts gathered here suggest that religious rituals operate as psychological resources through which athletes construct motivational meaning and prepare themselves mentally, within the culturally specific context of Turkish professional football.

#12 Intra-positional technical performance under different physical demands in elite football: a comparison between most demanding passage and extremely demanding passage

Reference: Front Physiol. 2026 Aug 6:17:1900931. doi: 10.3389/fphys.2026.1900931. eCollection 2026.
Authors: Zunqi Niu, Zhaoyang Wang, Yuntao Wang, Iyán Iván-Baragaño
Download link: https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2026.1900931/full
Summary: This study investigated positional differences in technical performance between the Most Demanding Passage (MDP) and the Extremely Demanding Passage (EDP) in elite football. EDP was defined as the top 5% of match phases based on position-specific high-intensity running (HIR) distributions. A total of 4,102 outfield player observations from 176 Chinese Super League matches were analysed, including 3,664 MDP and 438 EDP observations. Technical indicators were compared between MDP and EDP using both bivariate statistical analysis and a Random Forest classifier combined with SHAP (SHapley Additive exPlanations) to identify the most influential variables contributing to differences between conditions. Significant intra-positional differences were found. Central defenders increased short-pass accuracy (p < .001, ES = 0.62) and ball-carrying distance (p = .01, ES = 0.52), while reducing long passes (p < .001, ES = -0.44). Full-backs exhibited lower long-pass volume (p < .001, ES = 0.57) and forward pass length (p < .001, ES = 0.48). Central midfielders recorded fewer successful long passes (p < .001, ES = 0.34) and more ball losses (p = .03, ES = 0.30). Forwards showed declines in lateral passing (p = .02, ES = 0.37) and individual possession time (p = .002, ES = 0.36). Wide midfielders exhibited minimal changes between conditions. The Random Forest and SHAP analysis further indicated that passing actions (e.g., short passes, long passes) and ball progression behaviours (e.g., ball carrying) were the primary contributors to distinguishing EDP from MDP across playing positions. Overall, these results suggest that technical performance varies in a position-dependent manner under extreme physical demands, highlighting the importance of role-specific training strategies that replicate high-intensity match conditions.

#13 Navigating constrained training participation: a grounded theory of training avoidance among Chinese college football student-athletes

Reference: Front Psychol. 2026 Aug 3:17:1904154. doi: 10.3389/fpsyg.2026.1904154. eCollection 2026.
Authors: Yangjia Xiong, Minghan Li, Xingyuan Song, Ying Chen
Download link: https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2026.1904154/full
Summary: Training avoidance in sport is often interpreted through a deficit lens, yet little is known about how athletes regulate participation when leaving a team is institutionally costly. This study examined training avoidance within Chinese college football as a form of constrained participation. Semi-structured interviews were conducted with 16 Chinese college football student-athletes, all admitted through the Sports Special Admission policy. Data were analyzed using Straussian grounded theory procedures, including iterative theoretical sampling, constant comparison, open, axial, and selective coding, and negative-case analysis. The analysis generated Navigating Constrained Training Participation as the core category. Four causal conditions shaped training avoidance: Status Marginalization Pressure, Inter-Role Conflict, Informal Power Oppression, and Asymmetrical Rule Enforcement. Athletes responded through a flexible, context-dependent repertoire of Covert Energy Conservation, Psychological Defense, Legitimation Maneuvering, and Overt Resistance. These strategies were not a fixed progression; athletes combined, revisited, or abandoned them as perceived risk, bodily capacity, available justifications, and coach relations changed. The process provided short-term protection while potentially contributing to longer-term erosion of skill, belonging, and participation. Training avoidance is better understood not as an individual moral deficit but as a systemically produced and structurally conditioned adaptation. The model clarifies how athletes exercise constrained agency and offers a transferable explanation for sport-education systems in which exit is costly and participation is tied to educational opportunities, grading, resources, or status.

#14 Changes in saliva composition during different training phases in professional football players

Reference: Front Dent Med. 2026 Aug 5:7:1869353. doi: 10.3389/fdmed.2026.1869353. eCollection 2026.
Authors: Antoon J M Ligtenberg, Ektor C Petras, Kamran Nazmi, Henny Solleveld, Marja L Laine, Sergio Bizzarro
Download link: https://www.frontiersin.org/journals/dental-medicine/articles/10.3389/fdmed.2026.1869353/full
Summary: This study investigated changes in salivary biomarkers collected by oral rinsing during different phases of a standard professional football training, and how these changes correlated with perceived training intensity. This study included 28 professional football players. Saliva was collected by means of oral rinse with water. It was collected at three time-points during a single training session: before training, after warming-up, and after outdoor training. Players were asked to self-report the intensity of the training after each time-point on a scale from 1 to 10. The following biomarkers were measured: protein, carbohydrate and immunoglobulin-A (IgA) concentrations, and enzymatic activity of α-amylase, lactoperoxidase and lysozyme. Protein concentration increased during training (p < 0.001). α-Amylase activity/protein ratio (p < 0.001) increased while the IgA/protein ratio(p < 0.001) and carbohydrates/protein ratio (p = 0.001) significantly decreased. No association was found between the self-perceived intensity of training and changes in the biomarkers. This study shows that saliva composition changes in response to a regular football training session. These changes did not correlate with self-perceived intensity of training.

#15 Effect of a theory-based coach education program on the objectively assessed motivational climate in grassroots football across four European countries: results from the Promoting Adolescent Physical Activity (PAPA) project

Reference: Front Psychol. 2026 Aug 5:17:1563931. doi: 10.3389/fpsyg.2026.1563931. eCollection 2026.
Authors: Yannis S Tzioumakis, Damien Tessier, Nathan Smith et al.
Download link: https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2026.1563931/full
Summary: This study examined the longitudinal effects of the Empowering Coaching™ program, designed to promote more adaptive motivational climates as created by coaches in grassroots youth football across different countries. Sixty-eight coaches from four countries (England, France, Spain, and Greece) were randomly assigned to either the intervention or control group. Coaches‘ behaviors were assessed at three time points during the season using a validated observational system based on motivational theories. A series of linear and quadratic multilevel models revealed that, compared to the control group, intervention coaches demonstrated a significant reduction in disempowering behaviors (i.e., ego-involving climate) across the season and a temporary increase (assessed 1 month post-intervention) in features of an empowering climate (i.e., autonomy support and relatedness support). Findings highlight the training program’s short- and long-term impacts and point to the need for continued support to sustain positive coaching practices and reduce the occurrence of negative coaching behaviors.

#16 Food intake sequence affects postprandial metabolic, hormonal, and appetite responses in healthy male football players: a randomised crossover trial

Reference: Clin Nutr ESPEN. 2026 Aug 19:105037. doi: 10.1016/j.clnesp.2026.105037. Online ahead of print.
Authors: Rita Giro, Cristina P Monteiro, Catarina B Oliveira, et al.
Download link: https://www.clinicalnutritionespen.com/article/S2405-4577(26)02134-0/pdf
Summary: Food intake sequence can influence postprandial glycaemia and appetite in non-athletic populations. However, it remains unclear whether these effects extend to athletes, who often consume high-carbohydrate diets and exhibit distinct metabolic responses. This study aimed to compare postprandial metabolic and appetite responses to two food intake sequences in athletes. In a randomised, counterbalanced, outcome assessor-blinded crossover trial, 14 highly trained male football players [22.9 (3.1) y, 23.4 (1.7) kg.m-2, 5.3 (0.4)% HbA1c] consumed a standardised breakfast in a carbohydrate-last or carbohydrate-first meal pattern, separated by 1-2 weeks. The primary outcome was postprandial glucose; secondary outcomes included postprandial insulin, total GLP-1, GIP, ghrelin, PYY, triglycerides, NEFA, and appetite ratings serially measured over 3 h, and subsequent 3-6-h ad libitum dietary intake. Postprandial responses were analysed as summary statistics and time course data. The carbohydrate-last intervention elicited lower glucose incremental area under the curve (iAUC) from 0-60 min (-54 [-79 to -29] mmol.L-1×min, p < 0.001) and incremental peak (-1.7 [-2.4 to -1.0] mmol.L-1, p < 0.001), higher GIP iAUC0-60min (1705 [46 to 3363] pg.mL-1×min, p = 0.045), lower ghrelin total area under the curve from 0-180 min (-14542 [-28804 to -279] pg.mL-1×min, p = 0.046), and higher triglyceride iAUC0-180min (10.80 [0.04 to 21.56] mmol.L-1×min, p = 0.049). Despite lower ghrelin, participants reported greater mean hunger (5 [1 to 9] mm, p = 0.007), desire for sweet (-6 [-9 to -2] mm, p = 0.001) and salty foods (-5 [-9 to -2] mm, p = 0.002), and lower satiety (-5 [-8 to -2] mm, p = 0.002) than after the carbohydrate-first condition. In highly trained male football players, a carbohydrate-last meal pattern elicited lower postprandial glycaemia and ghrelin, but greater GIP, triglycerides, hunger, and cravings, without affecting 3-6-h ad libitum intake. Food intake sequence may alter short-term metabolic and appetite regulation in athletic populations.

#17 Outlier detection of skill decision differences of football penalty takers from a data-driven perspective: multialgorit hm modeling and empirical research of eye-tracking data

Reference: Front Sports Act Living. 2026 Aug 4:8:1733178. doi: 10.3389/fspor.2026.1733178. eCollection 2026.
Authors: Zheng Li, Pu Hu, Hua Liu, Ruo Chen Dai
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC13481837/pdf/fspor-08-1733178.pdf
Summary: Defensive performance in football penalty kicks relies heavily on a goalkeeper’s visual anticipation and rapid decision-making capabilities. While identifying the visual search advantages of expert athletes is crucial for optimizing training, conventional eye-tracking metrics often fail to capture the complex spatial distribution patterns of gaze points. Integrating machine learning anomaly detection algorithms offers a novel methodological perspective for the precise quantification and analysis of visual strategy variations across different expertise levels. This study aimed to investigate the differences in visual search characteristics between expert and amateur football players during penalty defense tasks, leveraging eye-tracking technology and multiple machine learning algorithms. Gaze data were collected from 10 professional/semi-professional athletes (Expert Group) and 10 collegiate athletes (Amateur Group), resulting in 120 valid records. The Shapiro-Wilk test indicated that the gaze point coordinates (X and Y axes) were not normally distributed. Consequently, four machine learning anomaly detection algorithms-Density-Based Spatial Clustering of Applications with Noise (DBSCAN), Local Outlier Factor (LOF), Isolation Forest, and Elliptic Envelope-were employed to perform a systematic outlier analysis on the gaze coordinates. (1) DBSCAN results revealed a highly significant difference in outlier rates between the two groups (p=0.0053<0.01) . The outlier rate for the Expert Group (53.57%) was significantly lower than that of the Amateur Group (61.27%), with a medium effect size (Cohen’sd=0.46) . (2) Under a 5% contamination rate setting, no significant differences were detected by the LOF, Isolation Forest, or Elliptic Envelope algorithms (p>0.05) . (3) Composite analysis showed that the proportion of points identified as outliers by at least one algorithm differed significantly between groups (Expert: 54.47% vs. Amateur: 62.04%, p=0.0052 ), representing a practically meaningful difference (Cohen’sd=0.47) . Expert athletes exhibit more concentrated and stable visual search strategies (characterized by lower gaze outlier rates) during penalty defense compared to amateurs. The DBSCAN algorithm and composite indicators effectively quantify expertise-related visual search features, providing empirical evidence for understanding cognitive patterns and enhancing scientific training for football goalkeepers.

#18 Protecting the mental health of gay and bisexual players in men’s elite-level football

Reference: Lancet Psychiatry. 2026 Aug 18:S2215-0366(26)00244-0. doi: 10.1016/S2215-0366(26)00244-0. Online ahead of print.
Authors: Dinesh Bhugra, Ana Buadze, Alexander J Smith, Michael Liebrenz
Download link: https://www.thelancet.com/action/showPdf?pii=S2215-0366%2826%2900244-0

#19 Movement Configuration Elements in Football Players: Beyond Dynamic Correspondence Principles

Reference: Sports Med Open. 2026 Aug 18;12(1):119. doi: 10.1186/s40798-026-01093-y.
Authors: Oliver Gonzalo-Skok, Julio Tous-Fajardo
Download link: https://pmc.ncbi.nlm.nih.gov/articles/PMC13486447/pdf/40798_2026_Article_1093.pdf
Summary: In real-world football training, limited time is available for strength and conditioning sessions during the in-season period. The search for time-efficient strategies that concurrently enhance several locomotive-specific actions while preventing injuries seems crucial. Individual sports coaching literature has provided valuable concepts such as „transfer of training“ and „dynamic correspondence“ to describe the extent to which a given exercise may enhance sports performance, based on how closely it reproduces the exercise’s mechanical, neural, and metabolic demands. However, given the highly dynamic and stochastic nature of football movements, there is a need to introduce a more comprehensive and advanced training paradigm that includes the so-called movement/action configuration elements. These variables aim to shape how game-based football actions evolve during a real match situation and include the need to efficiently anticipate/compensate for perturbations and unknown or unexpected events by alternating eccentric overload unilateral, variable, and multidirectional movements. A review of how these elements may shape football movements is conducted to ultimately provide practical recommendations and tools for daily practice.

#20 Lumbar Disc Changes on Magnetic Resonance Imaging in Asymptomatic Elite Male Soccer Players

Reference: Sports Health. 2026 Oct 9:19417381261490770.doi: 10.1177/19417381261490770. Online ahead of print.
Authors: Tolgahan Korkmaz, Yener Ince, Kunal Kapur, Shwetha Sanapoori, Goker Utku Deger, Barlas Benkli
Summary: Soccer places substantial mechanical demands on the lumbar spine through repeated sprinting, rotation, and contact-related loading. Although lumbar magnetic resonance imaging (MRI) abnormalities are frequently observed in athletes, data studying the prevalence and distribution of lumbar disc pathology in this population remain limited. Asymptomatic lumbar disc herniation may be common in elite male soccer players and disc herniation burden may not necessarily be associated with lumbar-related missed training sessions. This is a retrospective observational cohort study evaluating lumbar MRI findings obtained at team entry and their relationship with missed training sessions. MRI and training data were analyzed from 46 male soccer players from a single elite European team between 2020 and 2024. Outcomes observed included number of lumbar disc herniations, disc height loss, herniation levels and subtypes (central vs paracentral), and number of missed training sessions. Data analysis was completed using SPSS v27. A total of 43 male soccer players were included. Asymptomatic lumbar disc herniations were common (43.2%). Lower lumbar levels were disproportionately affected with herniations occurring most frequently at L4-L5 (31.6%) and L5-S1 (39.5%) (P < 0.001). Central herniations predominated compared with paracentral herniations (P < 0.001). Disc herniation burden was not positively associated with missed training sessions. Lumbar disc herniations on MRI are common in asymptomatic elite male soccer players and occur predominantly at the L4-L5 and L5-S1 levels, with central herniations being the most frequent subtype. Lumbar disc herniation burden may not necessarily correlate with missed training sessions. Asymptomatic lumbar disc herniations may be common in elite male soccer players, without any correlation with participation in training sessions.

#21 Cardiorespiratory and Metabolic Adaptations to a 6-Week High-Intensity Interval Training Program at Different Intensities in Young Soccer Players

Reference: Res Q Exerc Sport. 2026 Oct 7:1-9.doi: 10.1080/02701367.2026.2734449. Online ahead of print.
Authors: Felipe de Almeida Silva, Eduardo Rauen, Pedro Jatene, Valmir Oliveira Silvino, Alex Martos Couto, Marcos Antonio Pereira Dos Santos, Danilo Marcelo Leite do Prado
Summary: This study compared the effects of high-intensity interval training (HIIT) prescribed at the respiratory compensation point (RCP) versus maximal aerobic speed (MAS) on cardiorespiratory and metabolic outcomes in young soccer players. Eighteen male national-level soccer players (15.7 ± .5 years) were randomly assigned to either the HIIT-RCP or HIIT-MAS group and completed a 6-week training program. The assessments included oxygen uptake (VO2) and running speed at the ventilatory anaerobic threshold and RCP, as well as relative buffering capacity, hypocapnic hyperventilation, blood lactate accumulation, and rate of perceived exertion. Significant improvements over time were observed in VO₂ max and running speed following the intervention (p < .05). Although no significant between-group differences were observed, moderate-to-large effect sizes were identified for VO2 and running speed at RCP and MAS, suggesting potentially relevant exploratory differences between interventions. Additionally, the HIIT-MAS group exhibited a greater increase in blood lactate, whereas rating of perceived exertion decreased over time in both groups. Both RCP- and MAS-based HIIT improved aerobic-related physiological variables following the 6-week intervention, with no significant between-group differences. These findings suggest that both HIIT prescription methods are effective options for enhancing aerobic fitness in youth soccer players.

#22 The effect of sex-specific footwear on cutting patterns in adolescent female soccer players

Reference: Sports Biomech. 2026 Oct 7:1-19.doi: 10.1080/14763141.2026.2741555. Online ahead of print.
Authors: Karen Chen, Ethan Wilkie, Nicolas Herrera, Moreno Morelli, Shawn Robbins
Summary: Sex differences have been identified in foot morphology and soccer-specific movement patterns. However, female-specific athletic footwear has only emerged recently, and research has yet to fully understand its impact on cutting patterns. This study examined the impact of female-specific soccer shoes and unisex soccer shoes on joint kinematics during cutting in adolescent soccer players. Thirty-two females completed unanticipated sidesteps at 45 ± 10 degrees, in both shoe conditions, captured using a markerless motion captures system. Principal component (PC) analysis and hierarchical linear model examined joint angle features against shoe conditions. PCs (PC1, PC2, PC3) represented either differences in joint angle amplitude or a change in angles between different cutting phases. Ankle findings related to greater dorsiflexion and inversion angles throughout cutting (PC1) and during midstance (PC2, PC3) in the female shoe than the unisex shoe. Knee findings related to lower flexion angles during the pre-contact/early cutting phase in the female shoe (PC2). Overall, the female shoe trended towards more optimal inversion, but riskier dorsiflexion and knee flexion patterns for knee injuries. However, direct indications to injury and performance require further exploration. Nonetheless, the presence of kinematic influences in sex-specific soccer footwear designs provides valuable insights for future research directions and footwear development.

#23 Acute, chronic, and detraining effects of dynamic stretching and tissue flossing on muscle function, sprint performance, balance, and proprioception, in soccer players with hamstring shortness: a three-arm parallel randomized controlled trial protocol

Reference: Front Sports Act Living. 2026 Sep 21:8:1919926.doi: 10.3389/fspor.2026.1919926. eCollection 2026.
Authors: Mohammad Alghosi, Hassan Daneshmandi, Ali Shamsi Majelan, Andreas Konrad
Download link: https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2026.1919926/full
Summary: Hamstring shortness is prevalent among soccer players and is associated with an increased risk of muscle strain and performance deficits. Dynamic stretching and tissue flossing are two interventions used to address flexibility impairments; however, research has predominantly focused on their acute effects. A significant gap remains in understanding their isolated, individual chronic (≥2 weeks) and detraining effects on comprehensive athletic performance. Hence, this randomized controlled trial protocol aims to compare the acute, chronic, and detraining effects of dynamic stretching versus tissue flossing on muscle function, sprint performance, balance, and proprioception in soccer players with hamstring shortness. A three-arm, parallel randomized controlled trial will be conducted. A minimum of 57 male adolescent soccer players with clinically diagnosed hamstring shortness will be randomly assigned to a dynamic stretching group, a tissue flossing group, or a control group. The intervention groups will perform their respective protocols three times per week for six weeks. The outcomes include hamstring range of motion, muscle strength, and muscle power, 20-meter sprint time, dynamic balance, and knee joint proprioception. All outcomes will be assessed at four time points: baseline, immediately after the first session (acute), after six weeks of training (chronic), and after a three-week detraining period (9 weeks). This trial will provide novel evidence on training- and detraining-related adaptations in response to two distinct intervention strategies. The findings are expected to clarify whether one modality offers superior immediate performance enhancement compared to chronic flexibility gains, and how well these effects are retained after detraining. The results will directly inform evidence-based recommendations for integrating these techniques into athletic training and injury prevention programs for soccer players.

#24 Effects of mental fatigue on agility and coordination in female soccer players under high ambient temperature

Reference: Front Physiol. 2026 Sep 21:17:1964642.doi: 10.3389/fphys.2026.1964642. eCollection 2026.
Authors: Yuankang Wang, Yimei Duan, Guotian Lu, Mengda Wu
Download link: https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2026.1964642/full
Summary: The aim was to explore the effects of mental fatigue (MF) induced under high ambient temperature on agility and coordination in female soccer players. A randomized crossover design was adopted. Twenty-four female soccer players were recruited, and 19 participants completed all experimental sessions in a randomized balanced crossover design under high temperature (≥32 °C) or normal temperature (23 ± 1 °C), including either a 45-min Stroop task or a neutral video-watching control task followed by the Illinois agility test and the Harre circuit test, with a one-week washout period. All 19 participants were included in the final statistical analyses.Two-way repeated-measures ANOVA was used to examine the main and interactive effects of ambient temperature and MF. The 45-min Stroop task successfully induced a mental fatigue state. High ambient temperature was associated with an overall elevation in subjective mental fatigue levels, with a large main effect size (p < 0.001, η²p=0.713). For agility, both MF and high temperature exerted independent detrimental main effects: MF significantly prolonged agility performance time (p < 0.001, η²p=0.603), and high temperature also significantly impaired agility (p = 0.002, η²p=0.414), with no significant interaction (p = 0.102). For coordination, a significant interaction was found between temperature and MF (p < 0.001). Simple effects analysis showed that MF had no significant effect on coordination under normal temperature (p = 0.751), and high temperature alone did not impair coordination (p = 0.757). However, the combination of high temperature and MF significantly deteriorated coordination (p < 0.001, dz = 1.247, 95% CI = 0.604~1.889). In addition, both MF and high temperature independently increased ratings of perceived exertion (RPE, p ≤ 0.001), while the decline in motivation was mainly attributed to high temperature (p = 0.003, η²p=0.397). No significant interaction was detected between ambient temperature and mental fatigue for agility performance, and the results were compatible with an independent additive pattern. For coordination, a significant Temperature × MF interaction effect was observed, whereby coordination performance was only significantly impaired when high ambient temperature and mental fatigue co-occurred. It is recommended to strictly manage athletes‘ cognitive load before matches in hot environments to reduce the risk of MF and maintain stable performance of specific physical qualities.

#25 The effect of a minimal-equipment resistance priming protocol on 24-hour neuromuscular performance in U19 male soccer players: A randomized crossover trial

Reference: J Sports Sci. 2026 Oct 5:1-15.doi: 10.1080/02640414.2026.2741487. Online ahead of print.
Authors: Enrique Cañadas-García, Carlos García-Sánchez, Raúl Nieto-Acevedo, Jaime González-García, Verónica Giráldez-Costas, Alfonso de la Rubia
Summary: The aim of this study was to examine the effects of a priming protocol based on vertical and horizontal drop jumps and 20-m sprints, performed before field training session on the neuromuscular performance and perceptual responses in U19 soccer players 24 hours later. Thirteen male soccer players participated in a randomized crossover trial. Countermovement jump (CMJ) was assessed at baseline, post-training field, and 24 hours later. Short recovery stress scale, visual analogue scale and 20-m sprint were assessed at baseline and 24 hours post-intervention. In the priming condition, a moderate reduction in 20-m sprint time was observed 24 hours after (d = -0.71), with 5 of 13 players exceeding the smallest worthwhile change. However, no significant differences (p > 0.05) were found between conditions. Furthermore, no improvements in CMJ performance were observed 24 h after priming condition. In the control condition, peak propulsive force (-4.09%; p = 0.004; d = -1.35) and peak braking force (-4.03%; p = 0.011; d = -1.18) decreased after field training. However, these impairments were not observed in the priming condition (p > 0.05). These findings suggest that priming protocol may improve sprint time in some players, although the CMJ response remained unclear.

#26 Playing the field: A retrospective analysis of anterior cruciate ligament injuries and playing position in elite female football (soccer) players

Reference: JSAMS Plus. 2026 Sep 23:8:100159.doi: 10.1016/j.jsampl.2026.100159. eCollection 2026 Dec.
Authors: Jesse Di Marco, Kylie Fitzgerald, Jane Fitzpatrick
Download link: https://pdf.sciencedirectassets.com/780506/1-s2.0-S2772696726X20014/1-s2.0-S2772696726000256/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEJz%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJGMEQCIH1auMkgmrOhj4ISv9qZ3y32eTnhpjAI7vsKZVvh%2BLXgAiB7Ukqp67mDZfS2cy80F3b%2B0bSo96SRcIMSGnwRcQkhhSqyBQhlEAUaDDA1OTAwMzU0Njg2NSIMAlqp7fcnaLZRoIJHKo8FxIraKw5QUPadlL%2FabGc1agLX6yXEAe%2FOeugOLRAKW%2BNieFFzz48trAfz6marr%2BcgeFKdbxHvHcYSFKuaZZPKwWYo1RZ3d38NFxhUx4DbLE%2Bpjm8sdnfK5FQLxxSGgJHZIiXWlYnMY19PLEVY2xIlN6K7Vp1rh5OfXZDYIVM8LF1uttndnUk%2BZKKiHYwRHTjF409g8fF3TxJvS9eB4rYXkIXPvAGyjhFTvxYiUPRCqUkNriN3rTqtIsAgRtCiGPsezjeUMrHxFwi1OZHOGrziGdiCmoqjWvDDppJxqPTjwtVqGwWxyWgRxbiLSj3eLXxkyyJ4m7E2RgLOQTTvhWtTTN1MFpSHFL%2FdqZLLoY5yQHumeP4ZfFaDeZaccr2mE7qf53tSHx8Cm3jAh8zHyNFXaKNzMr1pzUWRGNnJv%2BP7IzdpU9SwDLPa3TOaXgiMDH0OYNlBSmYoh4o8Qobos5M7DHwqz3EuSCSjjtXI60y8kHzf5FYYaaqRzBFW24xgJVXr8Q4NHj3zruirJjg1GdwEK2rppQg8jtbqZ9bp5qe3LP%2B5jUrtz%2BSVnoKUPdfBxVPtE6IS2v41jTDjtuW7PCFivj%2FKSdqFviNSnMHwK5o5%2FIJ9CEVDXYZR4wGYUPSsW2iyloLXqldhaNOMEVB%2FJ%2BCpEW4A6M8qZspdM5Xvr2eiqVsepG6FQb8Yh6OaGmBC1ftlzzRfu88%2BsrkxAttS6Nar3mzK6R%2FQwLXyPEI1zRlYU0yz9DDb%2F%2FJriItJY3s%2FWWGi6%2BqqIhQTzp4ajg4%2Bmd82P7fWzZy85hkvgm3zrqvchimyj0lHR5TFZz2eZzEhSpB6YwzfCT49%2B6dbrQWbLbPqfZCRBa3MLPF%2BHW7rXlJ%2BRDDthqzWBjqyAeJ4N0TqA1h3CZfra3uhdNwzSYUehtlh5SGv5iYv5e1Bd2Mm7hLG%2FpZV0Wnn7bnRKn3YfhysywLWG57tNeF5ebkfl%2Btw%2BGVRq4q0qIYaaJVm%2FmorvEPU%2FzQD5LLClxQxz1%2FH%2BDl4l4HC%2BxGoRsX2iUOdUnVVfPI4CIjor6OIZE%2FXco81tZM%2B8W5L3jQiZlIhmHTN8NX5n2chiRjJN9W4ngZwrVK12b89h%2FM4H%2BR70wZOqWw%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20261011T045101Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYR4MRYMFK%2F20261011%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=97458d1b4e8df50ad24cdea7dacdecfcc2fd44a464dc9558a2c8862a635f3c7f&hash=448043cc4bec43038d85b5d37080a5440db952b72678a6f0297ac422e1986b74&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S2772696726000256&tid=spdf-96ffef8c-0853-4c7d-8eee-2347b736584d&sid=f06791ee56e4c146728a9f41ddd3fe005f58gxrqa&type=client&tsoh=d3d3LnNjaWVuY2VkaXJlY3QuY29t&rh=d3d3LnNjaWVuY2VkaXJlY3QuY29t&ua=1e0605525e0d55065100&rr=a48b3f4beec095d8&cc=de
Summary: Female football (soccer) athletes occupy different playing positions of goalkeeper, defender, midfielder, and forward that may influence ACL injury risk. This study examined the relationship between ACL injury and playing position in elite female footballers, and analysed player age, injury duration and injury seasonal timing with playing position subgroup analysis. Retrospective observational study using third party collected data from public multimedia confirmed elite female football player ACL injuries from 01/01/2022-31/12/2024. Public databases confirmed playing position, age, playing league, injury date and return to competition date. Season injury timing was calculated using league schedule data. De-identified records were analysed; Categorical variables were reported as frequencies and percentages, analysed using Chi-Square tests. Continuous variables were reported as medians and interquartile ranges, analysed using Kruskal-Wallis tests. From 541 total ACL-injuries, midfielders were most frequently injured (n = 183, 33.8%), then defenders (n = 169, 31.2%), then forwards (n = 149, 27.5%) with no significant difference in frequency of injury (χ 2 = 3.497, df = 2, p = 0.174). Goalkeepers were least frequently injured (n = 40, 7.4%). ACL injuries were significantly increased in the first (n = 74, |Z| = 5.05, p < 0.001) and second (n = 69, |Z| = 4.27, p < 0.001) months of the playing seasons. All outfield playing positions confer similar ACL injury risk in elite female footballers. The lower goalkeeper ACL injury frequency likely reflects less goalkeepers in the population with reduced cumulative match-play exposure. Playing position injury trends are similar to those observed in elite male football. A high-risk window for ACL injury in the early competitive season is a novel finding for this cohort.

#27 Acute Effects of a Low Dose of Caffeine on Physiological and Performance Factors in Young Male Soccer Players: A Randomized Crossover Study

Reference: Curr Dev Nutr. 2026 Sep 3;10(10):109528.doi: 10.1016/j.cdnut.2026.109528. eCollection 2026 Oct.
Authors: Mohammad Mehdi Azizi, Mohsen Salesi
Summary: This research aimed to study the acute consumption of caffeine on the performance of young male soccer players in the Loughborough soccer passing test (LSPT) and Yo-Yo intermittent recovery test level 1 (YYIR1), and also on the heart rate (HR), blood pressure (BP), and rate pressure product (RPP), immediately after the YYIR1. In a randomized, counterbalanced, crossover design, 12 young male soccer players (16.5 ± 0.52 y; 63 ± 8.06 kg; training background: 4-5 sessions/wk) voluntarily completed 2 distinct experimental sessions: 1) caffeine and 2) placebo. In each test session, 1 h after taking a caffeine or placebo (flour) capsule (3 mg·kg-1), the participants first completed the LSPT and then the YYIR1. HR, systolic BP (SBP), and diastolic BP (DBP) were measured before the start, 1 h after the start, and immediately after the end of the YYIR1. Because the Shapiro-Wilk test confirmed the normality of the data, parametric tests [repeated-measures analysis of variance (ANOVA) and dependent t-test] were used to analyze the research questions. Two-way repeated-measures ANOVA revealed significant main effects of condition (P = 0.006) and time (P < 0.001) for HR, without a significant condition × time interaction (P = 0.144); however, post hoc analysis showed significantly higher HR after caffeine ingestion compared with placebo immediately after the YYIR1 (P = 0.025). A significant condition × time interaction was observed for DBP (P = 0.014), although pairwise comparisons showed no significant post hoc differences (all P ≥ 0.101). No significant main or interaction effects were found for SBP or RPP (all P ≥ 0.066). Within the limits of the current sample size, acute ingestion of 3 mg·kg-1 caffeine elicited modest physiological responses in adolescent soccer players, significantly augmenting postexercise HR without substantially altering BP, RPP, or soccer-specific performance factors. However, given the observed numerical improvements in functional test results, these findings should be interpreted cautiously, as low-dose caffeine may offer subtle practical benefits that warrant further investigation with greater statistical power.

#28 Foot-strike angle affects performance and injury risk during cutting in soccer athletes

Reference: J Sports Sci. 2026 Oct 4:1-10.doi: 10.1080/02640414.2026.2741752. Online ahead of print.
Authors: Alex N Denton, Emily Karolidis, Michael E Hahn
Summary: Female soccer athletes experience elevated rates of non-contact anterior cruciate ligament injuries, particularly during cutting tasks that require rapid energy absorption and generation at the knee. This study examined the effects of sex and fatigue on knee joint power and footstrike angle during unanticipated cutting in cleated footwear. Twenty athletes (10 M/10F) completed unanticipated cuts before and after a standardized fatigue protocol. Kinematic and kinetic data were collected, and knee joint power and footstrike angle were calculated using standard inverse dynamics. Neither sex nor fatigue significantly influenced peak positive knee joint power (p > 0.05), although greater power was associated with faster approach velocities (p = 0.040). In contrast, peak negative knee joint power was greater in females, indicating a greater rate of energy absorption at the knee (p = 0.027). Footstrike angle differed by sex (p = 0.026), with females demonstrating greater angles at initial contact. A moderate negative correlation was observed between footstrike angle and peak negative knee joint power (r = -0.64, p = 0.005). These findings suggest that sex-related differences in cutting strategy may influence how energy is absorbed at the knee, with footstrike emerging as a potential contributor to these mechanical patterns.

#29 How key opinion leader characteristics influence women’s participation in soccer referee training

Reference: Front Psychol. 2026 Sep 18:17:1938303.doi: 10.3389/fpsyg.2026.1938303. eCollection 2026.
Authors: Kun-Feng Li, Chao Wang, Yi-Chi Zhang, Kai Hua
Download link: https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2026.1938303/full
Summary: Drawing on the Stimulus-Organism-Response (SOR) framework, this study developed a theoretical model linking key opinion leader (KOL) characteristics,perceived value, perceived fit, participation intention, and participation behavior to examine how key opinion leaders influence women’s participation in soccer referee training. Data were collected through a questionnaire survey, yielding 744 valid responses. Structural equation modeling and bootstrap analysis were used to test the proposed hypotheses and mediating effects. The results showed that KOL characteristics were positively associated with both perceived value and perceived fit, which were, in turn, positively associated with women’s participation intention. Participation intention further has a positive influence on actual participation behavior. However, the direct path of KOL characteristics, perceived value, and perceived fit on participation behavior are not significant, suggesting that women’s participation behavior is primarily shaped through the formation of participation intention. Bootstrap results further confirm that perceived value and perceived fit significantly mediate the relationship between KOL characteristics and participation intention, with 95% confidence intervals excluding zero. This study extends the application of SOR theory to women’s sports participation and soccer refereeing, offering a new perspective on the psychological mechanisms underlying women’s engagement in referee training.The findings also provide practical implications for soccer governing bodies seeking to improve female referee training systems, strengthen the role of influential role models, and promote the sustainable development of women’s soccer refereeing.

#30 Electrocardiographic profile of South African Premier League football players: A descriptive cross-sectional study

Reference: S Afr J Sports Med. 2026 Sep 15;38(1):v38i1a22987.doi: 10.17159/2078-516X/2026/v38i1a22987. eCollection 2026.
Authors: L Maqina, T C Muluvhu, P Nongogo
Download link: https://journals.assaf.org.za/index.php/sajsm/de/article/view/22987/26392
Summary: High-intensity soccer participation induces benign structural and functional cardiac adaptations collectively known as the athlete’s heart. However, sudden cardiac death (SCD) remains an important concern, emphasising the need for appropriate cardiovascular screening among competitive soccer players, particularly in settings where routine pre-participation cardiac screening protocols are not consistently implemented across all levels of competition nationally. The aim was to assess resting sport electrocardiogram (ECG) profiles of South African professional soccer players using international consensus standards for ECG interpretation in athletes. This cross-sectional study included 105 male South African Premier Soccer League players aged 17-39 years. Resting ECGs were recorded using the Custo-med Diagnostic Sport ECG device and interpreted according to international consensus criteria for athlete ECG interpretation. Age and weight were not significantly associated with cardiac risk level (p=0.867 and p=0.400, respectively). Heart rate was significantly associated with risk level (p=0.002), with players presenting heart rates ≥76 bpm showing a higher proportion of moderate risk (63.6%). No significant associations were observed between age, weight, or heart rate and T-wave inversion. Heart rate was significantly associated with right atrial enlargement (p=0.037), particularly among players with heart rates ≥76 bpm, whereas age and weight showed no significant associations. Resting ECG screening may assist with the early identification of potentially important cardiac abnormalities in South African soccer players. Annual ECG screening should be considered for both development and senior squads, together with appropriate clinical follow-up and emergency preparedness. These findings support broader cardiovascular screening strategies aligned with international football medicine recommendations.

#31 Temporal dynamics of alpha-band cortico-cortical coherence during motor preparation for successful and unsuccessful football penalty kicks

Reference: Front Psychol. 2026 Sep 23:17:1949955.doi: 10.3389/fpsyg.2026.1949955. eCollection 2026.
Authors: Guo Lu, Ming-Yang Cheng, Dan Li, Hatem Elbanna, Kuo-Pin Wang
Download link: https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2026.1949955/full
Summary: Successful motor performance may depend on the efficient coordination of cognitive and motor processes during movement preparation. Although previous electroencephalographic studies have linked alpha-band (8-13 Hz) coherence with performance in upper-limb precision tasks, little is known about cortico-cortical communication preceding successful lower-limb actions. Sixteen skilled football players performed penalty kicks under an individualized task-difficulty condition. EEG coherence was calculated for eight electrode pairs connecting the left and right temporal regions with frontal, central, parietal, and occipital midline sites. Coherence was examined during an early preparation period from -2,000 to -1,000 ms and a late preparation period from -1,000 to 0 ms before kick initiation. Successful kicks showed significantly lower Fz-T7 coherence than unsuccessful kicks across both preparation periods. Successful kicks also exhibited lower Cz-T8 coherence during the late preparation period. Lower Fz-T7 coherence may reflect reduced interaction between verbal-analytical processing and motor planning, whereas lower Cz-T8 coherence may indicate reduced coupling between visuospatial processing and motor-control processes immediately before kick initiation. These findings extend previous evidence from upper-limb precision tasks to football penalty kicking and support the psychomotor efficiency hypothesis. Successful kicking appears to be characterized by selective and time-dependent reductions in functional coupling rather than a general decrease in cortical connectivity.

#32 Short Term Effects of Football Headers on Reaction Time and Symptomology in Males and Females

Reference: Eur J Sport Sci. 2026 Nov;26(11):e70251.doi: 10.1002/ejsc.70251.
Authors: Yusef Mohammed, Rithik Rajan, Benjamin Tari, Flaminia Ronca
Download link: https://onlinelibrary.wiley.com/doi/epdf/10.1002/ejsc.70251
Summary: Football heading is a form of repetitive head impact linked to cognitive decline. Although the English Football-Association have implemented heading restrictions, evidence guiding sex-specific protocols remains limited. This study explored the acute effects of a standardized heading drill on reaction time (RT) and concussion symptomology and whether sex moderates these outcomes. 51 participants (25 females; mean age 22.8 ± 4.1 years), comprising recreational and university-level footballers, were non-randomly assigned to a heading group performing a 10-header drill, or a non-heading control group completing a regulated rest period. Immediately before and after the interventions, both groups completed tasks assessing simple reaction time, sustained attention, inhibition, and spatial timing anticipation and self-reported concussion symptoms via the Sport Concussion Assessment Tool, sixth edition (SCAT-6). SCAT scores increased significantly post-intervention only in the heading group (p = 0.002, dz = 0.59), with higher post-heading scores compared to the control group (p = 0.009, d = 0.66). No significant main effect of sex (p = 0.08) nor any interactions involving sex were found for RT and symptomology (ps ≥ 0.22). No significant changes in RT for any cognitive test were observed for any condition (ps ≥ 0.14). These findings suggest that a 10-header-drill has significant effects on symptomology, but no measurable effect on RT, and that sex did not influence either outcome. This supports the need to monitor sub-concussive symptoms post-heading. Future research should assess both immediate and longer-term effects of stronger, game-representative headers, across a wider range of cognitive domains.

#33 An applied framework for multi-domain player evaluation in professional football: Ranking agreement between traditional and expected-goals-derived metrics

Reference: J Sports Sci. 2026 Oct 4:1-15.doi: 10.1080/02640414.2026.2743324. Online ahead of print.
Author: Jongwon Kim
Summary: This study proposed an applied framework for evaluating football player performance using expected-goals (xG)-derived metrics and examined how player rankings from these metrics differed from those produced by traditional event-based indicators. Match-event and tracking-derived data from the 2025 K League 1 season were analysed across four domains: finishing, shooting, chance creation, and goalkeeping shot-stopping. Ranking agreement was quantified using Spearman’s ρ and Kendall’s τ, the mean absolute rank difference (also expressed as a percentage of N), and the proportion of players exceeding predefined absolute (≥5 and ≥10 positions) and relative (≥20% of N) rank-shift thresholds interpreted as applied heuristics rather than validated cut-offs. Moderate-to-strong correlations were observed across all four domains (ρ = 0.58 to 0.85, all p < 0.001); however, substantial individual-level discrepancies persisted, with mean absolute rank differences of 3 to 16 positions and at least 44% of outfield players re-ranked by ten or more positions. Because the study does not validate either ranking against an external criterion, it establishes that traditional and xG-derived metrics are not interchangeable rather than that either ordering is more valid. xG-derived metrics are best interpreted as complementary, context-sensitive information alongside traditional indicators for scouting, recruitment, and tactical decision-making.

#34 No clear association between time to return-to-play and first additional injury in European professional football players after ACL injury: A media-based study

Reference: J Exp Orthop. 2026 Oct 3;13(4):e70934.doi: 10.1002/jeo2.70934. eCollection 2026 Oct.
Authors: Andrea Marchetti, Michelangelo Scordo, Lorenzo Scarpi, Massimiliano Colotti, Belinda Trobec, Raffaele Sabot, Manuela Deodato
Summary: The primary aim of this media-based study was to investigate whether time from anterior cruciate ligament (ACL) injury to return to play (RTP) was associated with the hazard of a first additional injury over calendar time among male professional football players in the five major European leagues. Secondary aims were to examine associations with a first additional injury within 365 days after RTP and with the number of official competitive matches missed because of the first additional injury. Male professional football players who sustained an ACL injury, underwent ACL reconstruction and returned to official competition were identified from publicly available data. RTP was defined as the first official competitive match after ACL injury. Cox proportional hazards regression assessed associations over the full follow-up and within 365 days, adjusted for age and player position. Sensitivity analysis examined predefined RTP categories; negative binomial regression assessed the association between time to RTP and the number of official competitive matches missed because of the first additional injury. Among 278 players, mean time to RTP was 242.3 ± 99.5 days and 201 (72.3%) sustained a first additional injury. No clear evidence of an association was observed between time to RTP and the hazard of a first additional injury over the full follow-up or within 365 days. Similarly, no clear evidence of an association was observed in the categorical sensitivity analysis or between time to RTP and the number of matches missed because of the first additional injury. No clear evidence of an association was observed between time from ACL injury to RTP and the hazard of a first additional injury either over the full follow-up period or within 365 days after RTP. Similarly, no clear evidence of an association was observed between time to RTP and the number of official competitive matches missed because of the first additional injury.