Frontiers in Sports and Active Living最新文献

{"title":"Athletes beyond sex categories: gender inclusivity, law and sport in India.","authors":"Tarun Tarun, Anamika Shukla, Niyati Pandey","doi":"10.3389/fspor.2026.1767095","DOIUrl":"https://doi.org/10.3389/fspor.2026.1767095","url":null,"abstract":"<p><p>India's sporting ecosystem remains deeply entrenched in binary classifications of sex, despite the country's long-standing cultural recognition of gender diversity and its progressive constitutional jurisprudence on gender identity. This paper examines India's engagement with transgender, non-binary, and sex-variant athletes, highlighting the disconnect between legal recognition and sporting governance. While landmark judicial decisions such as NALSA vs. Union of India (2014) have affirmed the right to self-determined gender identity and constitutional guarantees of dignity, equality and non-discrimination, these principles have yet to be meaningfully operationalised within Indian sport. Through a socio-legal analysis of prominent Indian case studies of Anaya Banger, Aryan Pasha, Dutee Chand, Shanthi Soundararajan, and Nandini Agasara, the paper illustrates how athletes who fall outside normative sex-based classifications face invasive scrutiny, regulatory exclusion, privacy violations, and social stigma. These cases demonstrate how sports authorities frequently conflate transgender identity with intersex variations and natural biological diversity, resulting in inappropriate eligibility standards and coercive medical practices. The paper situates these experiences within broader international developments, including fragmented global sporting regulations. The analysis further explores India's constitutional framework, statutory protections under the Transgender Persons (Protection of Rights) Act, and relevant international human rights obligations, arguing that the principal barrier to inclusion is not the absence of rights but the failure to implement them within sport-specific governance. The paper concludes by proposing pathways for reform, including the adoption of uniform national guidelines, affirmative support measures, institutional sensitisation, and evidence-based policy design. It argues that inclusive sport is not merely a matter of competitive fairness, but a measure of democratic belonging, dignity, and substantive equality in practice.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1767095"},"PeriodicalIF":2.6,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13133015/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Student-athlete dual careers in South African public universities: insights from an ecological perspective.","authors":"Funani Mabala, Siphesihle Vundisa, Karabo Maila, Siphokazi Mbali, Natasha Janse van Rensburg","doi":"10.3389/fspor.2026.1798187","DOIUrl":"https://doi.org/10.3389/fspor.2026.1798187","url":null,"abstract":"<p><p>Student-athletes must navigate the complex demands of academic work and high-performance sport, often within higher education environments that place competing pressures on their time, energy, and performance. This study explores how student-athlete experiences differ across two South African public universities that vary primarily in their geographic setting, using Bronfenbrenner's Ecological Systems Theory and the Process-Person-Context-Time model as a guiding framework. An exploratory qualitative design was employed, with semi-structured interviews conducted with 22 undergraduate and postgraduate student-athletes (9 women, 13 men) engaged in high-performance sport. Data were analysed using inductive thematic analysis. Findings reveal that academic demands constitute the most persistent source of stress, driven by externally regulated assessments and long-term academic consequences, whereas athletic pressures are largely development-focused and internally regulated. Personal attributes such as motivation, resilience, and goal orientation, along with peer and team support, emerged as critical resources; however, injuries, transitions, and cumulative fatigue frequently disrupted coping mechanisms. Despite differences in institutional context, experiences were broadly similar, highlighting that dual-career engagement is shaped by ongoing interactions between individuals and their environments rather than singular determinants. Based on these insights, a conceptual framework is proposed that integrates person, process, context, and time dimensions, offering both theoretical and practical guidance for designing ecologically informed support systems that enhance sustainable dual-career development in higher education.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1798187"},"PeriodicalIF":2.6,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13133635/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exercise enjoyment and school sports: PE, general activity, and sports club participation.","authors":"Lasse Vogt, Lutz Vogt","doi":"10.3389/fspor.2026.1792875","DOIUrl":"https://doi.org/10.3389/fspor.2026.1792875","url":null,"abstract":"<p><strong>Background: </strong>Enjoyment of physical activity is a central determinant of lifelong engagement in exercise and health-oriented behavior.</p><p><strong>Objective: </strong>The present study examined associations between enjoyment of physical education (PE), general exercise enjoyment, and sports club participation among secondary school students.</p><p><strong>Methods: </strong>Sixty-two students (18 ♀, 44 ♂; grades 5-10) completed an anonymous survey including the Physical Activity Enjoyment Scale-short version (PACES-S), self-reported PE grades, and current and previous sports club/fitness memberships. Responses on PE enjoyment and perceived performance relative to classmates were collected using four-point scales. Data were analyzed descriptively and inferentially using Jamovi 2.6.26 (<i>α</i> = 0.05).</p><p><strong>Results: </strong>Three-quarters of students reported frequent or consistent enjoyment of PE. This group achieved significantly higher PE grades (1.98 ± 0.89 vs. 2.57 ± 1.16; <i>p</i> = 0.045) and higher PACES-S scores (15.5 ± 3.2). Active sports club members reported significantly greater movement enjoyment than non-members (<i>p</i> < 0.05). Students who consistently enjoyed PE were five times more likely to report above-average enjoyment of general movement (RR = 5.0; 95% CI: 1.97-12.69) and four times more likely to be active sports club members (RR = 4.36; 95% CI: 1.41-13.42).</p><p><strong>Conclusions: </strong>Enjoyment of PE is strongly associated with general movement enjoyment and sports club participation. These results underscore the importance of competence-oriented, diverse, and enjoyable PE curricula and suggest that school-sports club collaborations can enhance intrinsic motivation, self-efficacy, and social engagement, promoting sustained physical activity in youth.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1792875"},"PeriodicalIF":2.6,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13133634/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147813828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Match-day peaks and post-match compensation: divergent weekly load profiles of starters vs. non-starters in professional women's soccer.","authors":"Pedro Schons, Artur Avelino Birk Preissler, Suellen Dos Santos Ramos, Adam Kawczyński, Aleksandra Kisilewicz, Robert Trybulski, Filipe Manuel Clemente","doi":"10.3389/fspor.2026.1746747","DOIUrl":"https://doi.org/10.3389/fspor.2026.1746747","url":null,"abstract":"<p><strong>Introduction: </strong>Recent evidence indicates differences in training and match loads between starters and non-starters in women's soccer, but little is known about players in Brazil's elite leagues. This study aimed to compare the external and internal loads of professional women's soccer players classified as starters and non-starters during training sessions and matches.</p><p><strong>Methods: </strong>Twenty-nine players from a professional team competing in the Campeonato Brasileiro Série A1 (64.1 ± 6.8 kg; 167.3 ± 6.1 cm) were monitored. Internal load was assessed using the rating of perceived exertion (RPE), while external load variables included total distance, distance in different speed zones, high-speed running distance, number of sprints, maximum speed, accelerations and decelerations, recorded via Global Positioning System devices. Independent t-tests and Mann-Whitney <i>U</i> tests compared groups.</p><p><strong>Results: </strong>Starters accumulated higher match-day (MD) loads, with greater total distance (9999.0 ± 1205.7 vs. 5141.1 ± 1290.5 m; <i>p</i><0.01) and RPE (8.0 [7.0 - 9.5] vs. 4.5 [4.0 - 5.5] A.U.; <i>p</i><0.01). Conversely, non-starters presented higher values after matches, covering more distance on MD+1 (4655.1 ± 996.1 vs. 2390.4 ± 814.4 m; <i>p</i><0.01) and MD+2 (4210.0 ± 992.0 vs. 2979.4 ± 526.7 m; <i>p</i><0.01), along with higher RPE (7.0 [7.0-7.4] vs. 3.5 [2.5-5.0] A.U.; <i>p</i><0.01, and 6.5 [6.0-7.0] vs. 4.0 [3.5-5.0] A.U.; <i>p</i><0.01).</p><p><strong>Discussion: </strong>As conclusion, starters concentrated peak loads on MD, whereas non-starters accumulated higher loads on MD+1/MD+2. These findings support individualized post-match compensation for non-starters and recovery-focused management for starters.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1746747"},"PeriodicalIF":2.6,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13132872/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Movement organization and neuromuscular coordination underlying offensive performance in para-fencing.","authors":"Nawfal Mahdi, Udai Mahdi, Inaam J Sadiq, Rafid Qaduri, Noora Mustafa, Maher Asi, Mohammed Bader, Safaa A Ismaeel","doi":"10.3389/fspor.2026.1802474","DOIUrl":"https://doi.org/10.3389/fspor.2026.1802474","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background/objectives: &lt;/strong&gt;Para-fencing performance emerges from the interaction of kinematic execution, neuromuscular coordination, and mechanical constraints rather than from execution speed alone. Understanding how these factors combine into distinct performance strategies is essential for individualized assessment and training in adaptive sports. The primary objective of this study was to identify distinct performance strategies in para-fencers by deriving kinematic profiles from inertial measurement unit (IMU) data collected during a standardized offensive task. A secondary objective was to examine whether these strategies could be differentiated based on neuromuscular coordination patterns assessed using surface electromyography (sEMG), along with passive muscle mechanical properties and isometric strength measures.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Thirty para-fencers performed repeated offensive actions toward a fixed target under controlled laboratory conditions. Upper-limb kinematics and trunk stability were quantified using IMUs, while sEMG was used to assess muscle activation timing, burst characteristics, and agonist-antagonist co-contraction. Passive muscle mechanical properties were evaluated using myotonometry, and isometric strength was measured with a calibrated force device. IMU-derived kinematic features were standardized and analyzed using cluster analysis to identify distinct performance strategies. Between-cluster comparisons were conducted for performance outcomes, neuromuscular variables, muscle mechanical properties, and strength measures.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Three distinct performance strategies were identified. One strategy was characterized by high peak angular velocity, increased trunk oscillation, and greater movement variability, reflecting a fast but variable execution pattern. A second strategy demonstrated smoother movement execution, reduced trunk sway, lower co-contraction levels, and superior accuracy, representing a stable-accurate profile. The third strategy exhibited intermediate characteristics, indicating a balance between execution speed and control. Neuromuscular coordination patterns, passive muscle mechanical properties, and isometric strength measures further differentiated the identified strategies.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;Para-fencing performance is organized through distinct movement strategies that reflect differences in kinematic control, neuromuscular coordination, and mechanical constraints rather than speed alone. In the context of this study, movement strategies refer to distinct patterns of movement organization that emerge from the interaction between kinematic execution, neuromuscular coordination, and underlying mechanical properties. These strategies reflect how athletes adapt their motor behavior to task-specific and environmental constraints in order to achieve performance goals. Profiling-based biomechanical approaches provide valuable insight i","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1802474"},"PeriodicalIF":2.6,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13127253/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Manipulating player numbers in small-sided soccer games: effects on numerical superiority and inferiority across physiological, physical, technical, and tactical performance.","authors":"Michael C Rumpf, Johannes Jäger, Rhodri S Lloyd, Matthias Lochmann","doi":"10.3389/fspor.2026.1813770","DOIUrl":"https://doi.org/10.3389/fspor.2026.1813770","url":null,"abstract":"<p><p>Small-sided games (SSG) are widely used in soccer training to replicate the physiological, physical, technical, and tactical demands of competition within representative contexts. Coaches often manipulate task constraints by creating numerical superiority or inferiority, which imposes specific demands and elicits targeted adaptations. This review aimed to synthesize the effects of numerical imbalances on player performance across physiological, physical, technical, and tactical domains. Evidence indicates that playing in numerical superiority consistently reduces physiological intensity (e.g., mean heart rate, time >90% HRmax) and high-intensity physical load (e.g., total distance, sprinting, accelerations), while increasing low-intensity activity such as walking. Oppositely, technical performance improves, with a higher number of passes and overall actions. Tactical behavior also adapts, with teams expanding playing length and width, covering more space near the opposition goal, and increasing attacking opportunities, while exploratory behavior and proximity to their own goal decrease. Conversely, teams in numerical inferiority adopt compensatory strategies, focusing on defensive organization and goal protection, which can reduce physical output and exploratory movement, particularly under high-inferiority conditions. Numerical imbalances in SSG seem to modulate physiological load, physical activity, technical execution, and tactical behavior. These findings provide a framework for optimizing training design and session planning in soccer, enabling coaches to manipulate player numbers to target specific performance outcomes.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1813770"},"PeriodicalIF":2.6,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13127116/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Riding toward inclusion: the journey of adapted cycling.","authors":"Stephanie Sorraghan, Sally Logan, Valerie Watchorn, Dion Williams, Danielle Hitch, Joanne M Watson, Kathryn Aedy, Therese Dogra, Pearse Fay, Matthew Haanappel, Aarti Shukla, Glen Lebeau, James Little, John McKenna, Kerry Townsend, Kate L M Anderson","doi":"10.3389/fspor.2026.1770473","DOIUrl":"https://doi.org/10.3389/fspor.2026.1770473","url":null,"abstract":"<p><strong>Introduction: </strong>This study examined how adapted cycles, as a form of assistive technology, support participation in sports and recreational activities for people with disability. Although physical activity is widely recognised for its benefits to physical health, psychological wellbeing, and social connectedness, people with disability continue to face significant barriers to meaningful inclusion in sport and recreation. Adapted cycles offer a means of addressing some of these barriers by enabling individuals to engage in cycling in ways that are responsive to their functional abilities and support needs.</p><p><strong>Methods: </strong>Using a qualitative research approach, this study drew on in-depth interviews with six participants, including children and adults, who had experience using adapted cycles across a range of contexts. This diversity allowed for a nuanced exploration of individual experiences. Data were analysed thematically to identify patterns related to engagement, perceived benefits, and factors influencing successful use.</p><p><strong>Results: </strong>Three key themes were identified: (1) navigating barriers and building pathways; (2) riding into wellbeing and inclusion; and (3) expanding horizons. Participants consistently reported improvements in physical health, including increased strength, endurance, and overall fitness. Many also described increased independence, noting that adapted cycles enabled them to access community spaces and engage in activities with reduced reliance on others. Importantly, these functional gains were valued for the ways in which they supported social inclusion. Participants described increased confidence and self efficacy, as well as a stronger sense of belonging when cycling with family members, friends, or within community groups.</p><p><strong>Discussion: </strong>Adapted cycles were perceived as facilitating social interaction, increasing visibility in public spaces, and challenging assumptions about disability and capability. The study also identified several contextual factors that shaped inclusive outcomes. These included access to customised and well-maintained equipment, quality assessment and selection services, accessible environments, and strong social support from peers, families, and organisations. Persistent barriers such as inaccessible transport and environments were noted to constrain inclusion opportunities. Overall, the findings contribute to broader discussions on inclusive recreation and assistive technology by demonstrating that the value of adapted cycling lies not in participation itself, but in its capacity to foster meaningful social inclusion and enhance wellbeing.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1770473"},"PeriodicalIF":2.6,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13125089/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reactive agility-evidence based suggestions for improvement.","authors":"Lutz Vogt, Felix Laukhardt, Christian Haser, Winfried Banzer, Tobias Engeroff","doi":"10.3389/fspor.2026.1809831","DOIUrl":"https://doi.org/10.3389/fspor.2026.1809831","url":null,"abstract":"<p><strong>Purpose: </strong>To examine the contributions of lower-limb eccentric strength, reactive strength, and cognitive inhibitory control to reactive agility performance.</p><p><strong>Methods: </strong>Forty-five healthy, physically active males (21.3 ± 3.5 years) performed eccentric and isometric strength testing of knee flexors and extensors (Biodex dynamometer), 30 cm drop jumps for reactive strength, and a computerized Stroop task (EncephalApp) for cognitive performance. Reactive agility was assessed via the Random Star Run (RSR) on the SKILLCOURT. Multiple linear regression analyzed associations of strength and cognitive performance outcomes with reactive agility.</p><p><strong>Results: </strong>Mean eccentric strength of the knee flexors (EccHam/kg) and extensors were 2.24 ± 0.44 and 4.07 ± 0.79 Nm·kg^- ¹; isometric strength was 1.71 ± 0.285 Nm·kg^- ¹ and 3.79 ± 0.751 Nm·kg^- ¹; RSR duration was 17.03 ± 1.36 s; Stroop Interference Score was 1.01 ± 1.07 s; Drop Jump height averaged 0.328 ± 0.058 m and ground contact time (DJ GCT) was 0.189 ± 0.024 s. Higher EccHam/kg, lower Stroop interference, and shorter DJ GCT predicted faster RSR performance (<i>R</i> ² = .338, <i>p</i> < 0.05). Thirteen participants exceeded the upper tertile on at least two variables (EccHam/kg ≥ 2.5 Nm·kg^- ¹, Stroop ≤ 0.415 s, DJ GCT ≤ 0.174 s) and showed significantly faster RSR times and roughly doubled likelihood of above-average reactive agility performance (RSR ≤ 17 s; RR = 2.04, 95% CI = 1.17-3.54).</p><p><strong>Conclusions: </strong>Reactive agility is enhanced by higher eccentric hamstring strength, superior cognitive inhibitory control, and fast stretch-shortening cycle execution. The identified cut-offs may serve as practical benchmarks for training programs targeting eccentric strength, cognitive control, and plyometric efficiency. These findings underscore the combined neuromuscular and cognitive determinants of reactive agility, warranting longitudinal studies to confirm causality.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1809831"},"PeriodicalIF":2.6,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13126726/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The exploration of immune system function changes in marathon athletes after high-intensity training by Agent-Based Model.","authors":"Hao Tian, Renzheng Zuo, Deng Wang, Guoping Qian, Qiang Ye, Adam Kawczyński, Robert Trybulski, Filipe Manuel Clemente","doi":"10.3389/fspor.2026.1780114","DOIUrl":"https://doi.org/10.3389/fspor.2026.1780114","url":null,"abstract":"<p><strong>Background: </strong>Marathon running imposes substantial metabolic demand. While the acute effects of exercise are well-documented, the chronic immunometabolic alterations associated with intensified training blocks in elite populations remain characterized by complex, non-linear dynamics. Contemporary debates persist regarding whether post-exercise lymphopenia represents immunosuppression (the \"open window\") or a functional redistribution of immune effectors. This study explored the chronic effects of a four-week high-intensity training (HIT) block on immune markers in professional marathon athletes and evaluated the utility of an Agent-Based Model (ABM) for visualizing these system behaviors.</p><p><strong>Methods: </strong>Twenty-two professional marathon athletes (14 male, 8 female) underwent a four-week intensified training protocol characterized by sustained time in the severe-intensity domain (blood lactate > 7.0 mmol/L). Peripheral blood samples were analyzed pre- and post-training for leukocytes, immunoglobulins (Ig), cytokines (IL-6, IL-8, IL-10, TNF-α), and lymphocyte subsets. Concurrently, a NetLogo-based ABM was developed to simulate theoretical immune system dynamics under metabolic constraints.</p><p><strong>Results: </strong>The training period coincided with significant shifts in circulating immune markers. Total leukocyte counts and serum IgG levels were significantly lower post-training (<i>P</i> < 0.01). A marked inversion in T-cell homeostasis was observed, with the CD4+/CD8+ ratio decreasing to 0.98 (<i>P</i> < 0.01), driven by a reduction in CD4+ cells and maintenance of CD8+ populations. Cytokine analysis revealed a \"resolution failure\" profile: while pro-inflammatory markers IL-6, IL-8, and TNF-α increased (<i>P</i> < 0.01), the anti-inflammatory cytokine IL-10 was significantly reduced (<i>P</i> < 0.001). The ABM simulation qualitatively reproduced these emergent patterns, visualizing the non-linear contraction of T-cell populations consistent with the empirical data.</p><p><strong>Conclusions: </strong>A four-week block of high-intensity marathon training is associated with a state of immunometabolic perturbation characterized by reduced circulating leukocytes, CD4+/CD8+ imbalance, and an uncoupled inflammatory-resolution cytokine response. While plasma volume expansion may contribute to the observed lower cell concentrations, the specific suppression of IL-10 and CD4+ cells suggests a maladaptive response to chronic load. The agent-based model serves as an exploratory tool for visualizing potential immunological tipping points during intensified training, bridging the gap between reductionist data and complex system dynamics.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1780114"},"PeriodicalIF":2.6,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13126728/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adapting a resistance training program for Danish physical education: teachers' preconceptions and participatory co-adaptation.","authors":"Sofie Koch, Marianne Friis Andersen, Malte Nejst Larsen, Jesper Ninn Sandfeld Melcher, Thomas Viskum Gjelstrup Bredahl, Christina Birch Meiner-Jensen, David R Lubans, Lars Breum Christiansen","doi":"10.3389/fspor.2026.1816683","DOIUrl":"https://doi.org/10.3389/fspor.2026.1816683","url":null,"abstract":"<p><strong>Introduction: </strong>Transferring and scaling school-based physical activity (PA) programs across educational contexts requires systematic adaptation to ensure implementation feasibility and contextual fit. This study examined Danish physical education (PE) teachers' preconceptions for resistance training and a participatory co-adaptation process used to adapt the evidence-based Resistance Training for Teens (RT4T) program for implementation in Danish lower secondary schools.</p><p><strong>Methods and materials: </strong>MEGAFiT, a Danish adaptation of RT4T, was developed using a sequential qualitative design. We conducted six online group interviews with 19 PE teachers and analysed data using the COM-B model to identify key implementation determinants related to capability, opportunity, and motivation. These findings informed four participatory co-adaptation workshops with 14 PE teachers, combining practical testing, reflection, and iterative program refinement. The resulting MEGAFiT program was structured as a six-week PE course consisting of modular, equipment-light resistance training sessions designed to integrate with PE content. Adaptations were documented using the Framework for Reporting Adaptations and Modifications-Expanded (FRAME).</p><p><strong>Results: </strong>Teachers' capability and confidence to deliver resistance training varied substantially and were closely linked to prior experience. Key implementation barriers included limited lesson time, large class size, and restricted access to facilities and equipment. During the co-adaptation process, teachers and researchers collaboratively refined the program by shortening its duration, introducing modular lesson structures, developing equipment-light exercise formats, and redesigning instructional materials to improve usability in PE settings.</p><p><strong>Conclusion: </strong>Explicitly addressing implementer preconceptions through structured co-adaptation strengthened the alignment between the RT4T program and the Danish school context. The findings illustrate how participatory adaptation can help tailor evidence-based PA programs to everyday PE practice by aligning program structure, organization, and materials with teachers' capabilities and contextual constraints.</p>","PeriodicalId":12716,"journal":{"name":"Frontiers in Sports and Active Living","volume":"8 ","pages":"1816683"},"PeriodicalIF":2.6,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13124729/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147814248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}