Search Results (3,946)

The rising popularity of sports practiced without adequate preparation has increased the incidence of anterior cruciate ligament (ACL) injuries, particularly among young individuals. Because the ACL has a very limited intrinsic healing capacity, surgical reconstruction—most often using autologous grafts—remains the standard of care. However, current techniques frequently lead to donor-site morbidity and do not consistently restore long-term joint stability, contributing to early post-traumatic osteoarthritis in active patients. Over the past decades, tissue engineering (TE) has opened promising avenues for developing biological substitutes capable of overcoming these limitations. Despite substantial progress, no strategy has yet demonstrated reliable and clinically validated functional regeneration of the human ACL. Meanwhile, artificial intelligence is emerging as a complementary tool for diagnosis, surgical planning, biomechanical assessment, and personalized reconstruction strategies. This review aims to provide a comprehensive overview of current TE-based approaches for ACL repair and reconstruction, analyzes their biological and biomechanical limitations, and discusses emerging concepts that may enhance future clinical outcomes. We first summarize the fundamental principles of tissue engineering, then examine the major strategies proposed for ACL regeneration—highlighting their respective strengths and shortcomings—and finally outline perspectives for a novel approach currently under development. Full article

Background and Objectives: Engaging in sports activities presents several benefits but also carries a risk of injury. Performing warm-up exercises may serve as a preventive measure against sports injuries. This study explored how participating in warm-up exercises is associated with complications, subsequent injury frequency, and recovery duration among athletes with a history of sports injuries. Materials and Methods: In this study, we performed cross-sectional secondary analysis of data derived from the 2024 Sports Safety Accident Survey conducted by the Korea Sports Safety Foundation, which is a nationally administered survey based on a structured questionnaire. The survey, conducted from November 2024 to December 2024, targeted 10,000 athletes aged ≥12 years registered in 64 sports nationwide. We utilized the data of 6063 athletes who had experienced sports injuries. The collected data were analyzed using frequency analyses, chi-squared tests, and multivariate logistic regression analyses. This study was conducted as a physical activity epidemiology study to examine associations between warm-up exercise participation and injury outcomes. Results: The likelihood of complications was higher among those who responded “not really” or “neutral” regarding participation in warm-up exercises. The likelihood of injuries was higher among those who responded “neutral” or “somewhat”. Furthermore, the likelihood of prolonged recovery was higher among those who responded “not really”, “neutral”, or “somewhat”. Conclusions: Performing warm-up exercises is an essential measure for athletes with a history of injuries to safely engage in sports activities. Therefore, it is necessary to highlight the importance of warm-up exercises among athletes and to implement a safety management system to encourage consistent performance. Full article

Major social, cultural, and sociopolitical events routinely disrupt daily life, yet their effects on sleep are rarely conceptualized at the population level beyond anecdotal sharing. The purpose of this Opinion piece is to initiate a preliminary discussion of “public sleep” as a novel construct describing systematic, event-related changes in sleep timing, duration, and quality that emerge coherently within communities in response to shared social experiences. Drawing on similarities with the well-established concept of public mood, we posit that sleep can be shaped by social environments in which shared attention, emotional climate, and coordinated schedules exert systematic influence. In support of this claim, we describe preliminary evidence from diverse domains demonstrating population-level sleep disruption following major events, including the transition to Daylight Saving Time, national elections, prolonged crises such as the COVID-19 pandemic and armed conflicts, and highly salient cultural activities such as major sporting events. These reports from disparate fields provide an initial indication that public sleep disruptions can be acute or prolonged, geographically localized or global, and may be shaped by the duration, emotional intensity, and perceived importance of the associated event. We further highlight the potential public health, safety, social, and economic consequences of collective sleep loss, underscoring its relevance beyond individual well-being. Finally, we outline key directions for future research, emphasizing the need for systematic reviews, mechanistic studies, longitudinal designs, and policy-relevant recommendations. Recognizing public sleep as a measurable population phenomenon would provide a foundation for anticipating, monitoring, and mitigating sleep disruption during periods of collective strain, with implications for both individual health and societal resilience. Full article

A warm-up is a critical procedure in sports science for enhancing muscular performance and optimizing subsequent athletic activities. However, the physiological and athletic performance effects of a warm-up are often transient, diminishing rapidly during the period of inactivity after the warm-up, which is known as the warm-up transition phase. In this study, a multi-functional thermoregulation wearable composite film of graphene–MXene–bacterial cellulose/polyethylene glycol (G-M-BC/PEG) was developed by integrating MXene (a two-dimensional material with good photothermal conversion performance) and graphene into a bacterial cellulose aerogel framework, subsequently impregnated with polyethylene glycol (PEG-2000). The film showed stable structure, efficient solar photothermal conversion and storage (SPCS), and improved mechanical properties. Under 1 sun irradiation, the optimized G-M-BC/PEG wearable film showed excellent SPCS performance, sustaining a temperature plateau of 38–40 °C for 10 min after the xenon lamp was switched off under 1 sun irradiation, with a leakage rate of only 5.32% after five cycles. By constructing a biomimetic sports human body model, the composite aerogel was shown to significantly elevate muscle surface temperature and effectively mitigate heat loss during the transition phase. In the warm-up effectiveness and sports performance tests, the wearable film improved 200 m sprint performance by 0.8% ± 0.4% (p = 0.039). It also maintained subjective thermal sensation during the warm-up transition phase, with no significant decline at 5 or 10 min after the warm-up and a significant decrease only at 15 min (p = 0.02), while thermal comfort remained stable, suggesting improved neuromuscular readiness. This research provided a novel strategy for the fabrication of advanced aerogel-based wearable devices aimed at precision thermal management and athletic performance optimization. Full article

To evaluate the effectiveness of an adaptive physical education (APE) program using VR technologies, we studied the physical development and vitality indicators of college female students in two groups: those with and without functional health limitations (N = 70 each). Students with disabilities were randomly divided into experimental and control groups of 35 people each. The experimental group participated in physical education classes using VR. The health assessment included heart rate, blood pressure, and subjective health assessments. Physical development was assessed by the biological age index (BAI) by Voitenko, static balance duration, and breath-holding time. Psychological activity was assessed using the Mindfulness Attention Awareness Scale (MAAS), the Rezapkina Vitality Test, and the Subjective Vitality Scale (SVS). The delayed effect was assessed using a questionnaire. Students with functional impairments initially demonstrated a significant decrease in overall vitality, physical activity duration, and more negative health self-perception. After the virtual reality sessions, they showed a restoration of physical development and vitality indicators to levels close to healthy, as well as a decrease in BAI. The delayed effect was confirmed after three months. The use of virtual reality technologies in the APE program effectively improves the physical development and activity (vitality) of students with functional health impairments. Full article

Background: Habitual physical activity (PhA) may contribute to overall physiological reserve, yet its relevance for lung transplantation (LTx) remains unclear, as existing studies almost exclusively explore short-term exercise interventions. This study evaluates whether life-course PhA before LTx influences postoperative outcomes: functional capacity measured by 6 min walk test (6MWT), chronic lung allograft dysfunction (CLAD), and length of hospital stay (LOS). Methods: In this retrospective study, ninety-seven LTx recipients completed the Historical Adulthood Physical Activity Questionnaire (HAPAQ), assessing PhA from age 20 to transplantation. All participants were assessed within the same time frame, with varying time intervals since transplantation. Patients were classified into no/recreational/intensive sport groups based on regular participation. Statistical analyses examined sport group differences in 6MWT, CLAD, and LOS and interactions with sex, pulmonary disease type, and secondary pulmonary hypertension (PH). Results: Lifelong PhA did not significantly differentiate quantitative 6MWT, CLAD, or LOS, and no interaction effects were observed. A modest trend was noted in patients without secondary PH, among whom intensive PhA corresponded to more frequent within-norm qualitative 6MWT results. Outcomes were comparable between single- and double-lung (DLTx) recipients, although a moderate effect between sports groups suggested a possible DLTx compensatory advantage. Conclusions: This study provides the very first life-course assessment of PhA in LTx recipients, highlighting the value of HAPAQ for estimating pre-transplant physiological reserve. Despite postoperative outcomes being largely independent of lifelong PhA, and recovery appearing multifactorial, habitual PhA should not be overlooked in developing individualized prehabilitation strategies in transplant medicine. Full article

Physical inactivity remains a major modifiable risk factor for non-communicable diseases and continues to exhibit marked socioeconomic and gender disparities in Latin America. Identifying robust and interpretable predictors of inactivity in nationally representative datasets is essential for informing public health strategies. This study compared a survey-weighted logistic regression model and an explainable machine learning approach (XGBoost) to predict physical inactivity among Chilean adults using data from the 2024 National Physical Activity and Sports Survey (ENAFyD; n = 5248). Models were evaluated on a stratified held-out test set (n = 1050) using weighted and unweighted area under the ROC curve (AUC), Brier scores, and calibration curves. Survey-weighted logistic regression achieved a weighted AUC of 0.801, while XGBoost achieved 0.797, demonstrating comparable discrimination. XGBoost showed marginally lower Brier scores, indicating slightly improved probabilistic calibration. Low socioeconomic status, female sex, lower monthly physical activity expenditure, limited facility access, and lower engagement with digital resources were consistently associated with higher inactivity risk. SHAP-style contribution analysis provided additional insight into feature-level influence within the machine learning framework. Overall, both approaches demonstrated similar predictive capacity, supporting the complementary use of classical regression and explainable machine learning for population-level physical inactivity research. Full article

The aim of this scoping review is to categorize and examine the relationships between school neighbourhood built environment categories and the physical health of children and adolescents worldwide. The search strategy initially found 8837 studies in four databases (Web of Science, PubMed, SportDiscus and Transportation Research Board) and after applying the inclusion and exclusion criteria 55 articles were included. The findings report on seven school neighbourhood built environment categories: building, connectivity and network, food environment, greenness, land use, safety and other variables. Interestingly, the connectivity and network category comprises 32 variables. Likewise, this category, together with the food environment, shows a clear predominance, with both categories accounting for 71.04% of all significant associations. The greenness category stands out due to its association density similarly to the predominant categories. The physical health categories were body composition, mode of commuting, physical activity, sedentary behaviour and weight status. Complementary weighted cross-tabulation analyses showed that when associations were weighted by participant sample size and school sample size, the food environment–weight status relationship became the most prominent, whereas connectivity-related associations became less dominant. The findings indicate preferential links between school neighbourhood built environment and physical health domains, with the connectivity and network category mainly associated with commuting mode and physical activity, and the food environment was primarily linked to weight status and dietary intake. Consequently, special attention must be given to urban planning and policies in the school neighbourhood built environment. Full article

Background: We assessed the effects of a 6-week, low-volume Nordic hamstring exercise (NHE) intervention on hamstring flexibility, muscle mechanical properties and eccentric and isometric isokinetic knee flexion strength in recreationally active adults. Methods: Eighteen recreationally active adults were randomized into an NHE intervention group (IG; n = 9; females/males: 3/6; mean ± SD, age: 24.1 ± 1.3 years) and control group (CG; n = 9; females/males: 5/4; mean ± SD, age: 23.5 ± 1.8 years). The NHE intervention involved a progressive, supplementary training program performed initially one (weeks 1 and 2) and then two times per week over a 6-week period. The number of repetitions per session increased from 15 to 36 repetitions/week. The CG maintained their usual exercise routine over the same period. Standard goniometry, myotonometry, and isokinetic dynamometry (60°/s) were used to measure hamstring flexibility, muscle properties and isometric and eccentric isokinetic strength prior to and five days following the intervention. Results: The Linear Mixed Methods analysis identified a significant group × time interactions for isometric torque (IG: +5% vs. CG: −12%, p = 0.022) and flexibility (IG: +1% vs. CG: +7%, p = 0.023). Peak eccentric torque (IG: +7% vs. CG: −7%, p = 0.053) and muscle mechanical properties remained unchanged over the intervention period. Conclusions: Six weeks of low-volume NHE training marginally improved isometric and eccentric hamstring strength in recreationally active adults without changing hamstring flexibility or mechanical properties. The findings may have important implications for performance enhancement and hamstring injury risk reduction during high-intensity recreational sports. Full article

Curling is a sport in which two teams take turns delivering stones on ice and compete for total scores. It is a highly strategic sport, often referred to as “Chess on Ice”. In recent years, research on curling AI and statistical analysis aimed at tactical evaluation has been active. Decision-making in curling highly depends on the current stone position state, so obtaining stone positions is essential for tactical analysis. This study proposes an object detection model capable of acquiring stone coordinates with high accuracy and generality from stone position images of actual games. The proposed model was realized with a small amount of manually annotated data and pseudo-labeled images. Using the active testing method, the image-level accuracy of data—a strict criterion requiring perfect detection of all stones in a single image—for approximately 100,000 items was estimated to be 99.37%. Furthermore, we measured the positional error of the detected stones and found an average result of 0.472 px. We determined that this model had sufficient accuracy for practical use, so we decided to store the acquired coordinates in a database and use them as training data for the curling AI and statistical analysis. Full article

Background/Objectives: Restoring lower-limb strength and symmetry is crucial after ACL injury and reconstruction. The limb symmetry index (LSI) is often used to assess strength symmetry for return-to-sport decisions, but various assessment methods can influence outcomes. This study aimed to compare LSI across common knee flexor testing methods in healthy male athletes and to examine associations between absolute strength outcomes, thereby establishing baseline reference values for LSI in a healthy population. Methods: Twenty-two healthy recreationally active males participated in this prospective cross-sectional study. Knee flexor strength was assessed bilaterally using three force plate isometric tests, a static dynamometer-based test (isometric), and isokinetic dynamometer-based tests. Absolute strength values were normalized to body mass. LSI values were calculated for each testing condition. Differences in LSI across modalities were analyzed with repeated-measures ANOVA, and associations between normalized strength outcomes were assessed using Pearson correlation coefficients. Results: LSI values ranged from 96.69 to 101.83 across the testing conditions, with no significant differences observed between measures. Normalized absolute strength outcomes demonstrated very strong correlations within the same measurement category (r = 0.86–0.94 for force plate tests and r = 0.88–0.96 for isokinetic tests). In contrast, correlations between isometric and isokinetic strength outcomes were moderate (r = 0.41–0.67). Conclusions: LSI values were consistent across knee flexor strength testing modalities, suggesting that symmetry assessment was relatively consistent across different measurement methods in the studied group. In contrast, normalized absolute strength outcomes showed only moderate and variable associations across modalities, indicating that different testing approaches assess related but not interchangeable aspects of muscle strength. Full article

Competitive eSports impose substantial cognitive workload, yet performance evaluation still emphasizes post-match statistics without considering players’ cognitive states. We reviewed 30 papers that recorded physiological signals using sensors and utilized machine learning (ML) for predicting cognitive states and/or game performance. Findings showed that cardiovascular monitoring (heart rate variability/HRV) was the most prevalent modality (20/30 studies), followed by oculometry (10), electrodermal activity/EDA (9), and electroencephalogram/EEG (5); however, no standardized protocols (device/pre-processing/feature subset) were observed across HRV studies despite it being the most common measure. The best outcomes per construct (measure, accuracy) were: mental workload (pupillometry, ~82%), stress/arousal (EDA, p < 0.001), cognitive fatigue (pupil diameter/EEG, ~88%), expertise (EEG, ~92%), and tilt (EDA/HRV/eye-tracking, ~82–87%). Notably, current studies used small samples and were gender-imbalanced, while ML studies often lacked cross-validation. Only 2 of 30 studies examined flow state—a mental state of optimal performance characterized by total immersion and effortless execution—and interestingly, HRV showed decreases during stress/workload but increases during flow, suggesting context-dependent autonomic regulation. To address this gap, a new framework for flow detection is presented. This review will be of interest to game developers, eSports players, and coaches, and the reported findings may help towards improving player experience and game performance. Full article

Introduction: Lower urinary tract symptoms (LUTSs), including urinary incontinence (UI), are common problems present in the general population. However, these symptoms have also been seen in young, elite-level athletes, especially females, including those who are nulliparous. This preliminary study aimed to report on the prevalence of LUTSs within an elite athletic population, including both males and females, within the UK high-performance system (the Sports Institute of Northern Ireland) and a women’s elite cycling team, while also investigating the link between LUTSs and specific training and sporting activities. Methods: A cross-sectional study of elite athletes in the Sports Institute of Northern Ireland (SINI) and a women’s professional cycling team, using an online questionnaire, was conducted to investigate the prevalence of LUTSs and UI and their impact on quality of life (QOL) among both male and female elite athletes. The authors used the STROBE-SIIS guidelines to produce separate electronic questionnaires for male and female athletes. This is a preliminary pilot study due to the small sample size. Results: Ten male athletes completed the IPPS questionnaire, reporting a median score of 5.5/35. Meanwhile, 18 female athletes completed the Athlete Female LUTS (A-FLUTS) questionnaire and reported a median score of 6/44. Female athletes had a higher prevalence of UI in the last four weeks (66.7%) compared to male athletes (20%). Of the 28 athletes, 7 were explosive/sprint athletes, and 21 were endurance athletes. Explosive/sprint athletes (71.4%) appeared to have a higher prevalence of UI in the last four weeks compared to endurance athletes (42.9%). Athletes self-managed these UI symptoms through a variety of methods, including reducing fluid intake, which could impact their athletic performance. This is a preliminary pilot study and—despite its small size—it defines a methodology and shows some important results that encourage research to be carried out on a larger sample size. Conclusions: The reported QOL impact and potential impact on health and athletic performance highlight the need for better management and treatment protocols, including the need to screen for urinary symptoms in the pre-season medical. Full article

The rapid development of modern sports has placed higher demands on athlete protection. Traditional protective gear relying on passive energy dissipation through bulk materials such as foam and gel suffers from limitations like large volume and poor adaptability, driving the evolution of protection technology toward active and intelligent solutions. Impact absorption and damping coating technology, which integrates advanced functional materials in thin-film form onto the surface of protective gear, has achieved a paradigm shift in protective performance and is advancing toward lightweight, intelligent, and customizable designs. This review first systematically elaborates on the working principles and performance regulation mechanisms of novel coating systems centered on shear-thickening fluids, polymer gels, microstructural biomimetics, and phase-change materials. Secondly, it deeply analyzes the application modes and protective efficacy improvements of these technologies in specific scenarios such as helmets, joint protectors, and smart clothing. Furthermore, it explores the complex interaction mechanisms between coatings and human tissues under dynamic impact. Finally, we discuss the challenges and future trends in the evolution of this technology toward multifunctional integration, dynamic adaptability, and precise personalized design, aiming to provide a systematic reference for interdisciplinary innovation in fields such as materials science, biomechanics, and sports medicine. Full article

Background/Objectives: Traditional biomechanical models describe human locomotion as an articulated chain of rigid segments with constrained degrees of freedom, primarily focusing on kinematic descriptions of movement. While this approach facilitates modelling and teaching, it may limit the representation of internal force transmission and dynamic interactions, particularly during transitional phases such as gait initiation. The objective of this article is to propose a conceptual framework, Unconstrained Segmental Biomechanics (USB), to reinterpret locomotor mechanics beyond rigid joint assumptions. Methods: An exploratory analysis of recent PubMed-indexed publications (2024) and commonly adopted educational references in sport science institutions was conducted to examine how locomotion is conceptually represented and to identify possible models analogous to the framework. The aim was to situate the framework within current modelling approaches rather than to provide a systematic literature evaluation. Results: The exploratory analysis provided an exploratory contextual impression that kinematic representations were more readily identifiable than conceptually analogous models explicitly addressing dynamic intersegmental force transmission. USB is presented as a conceptual framework generating testable biomechanical hypotheses concerning the temporal organisation of intersegmental force transmission during locomotor transitions, including the expectation that during gait initiation gluteus maximus activation precedes observable segmental displacement, that early CoP/GRF changes precede the visible step, and that trunk activation actively contributes to intersegmental force regulation during the transition. Conclusions: USB offers a conceptual framework that enriches the interpretation of gait initiation and locomotor transitions. Future empirical investigations will be necessary to test the biomechanical hypotheses generated by this framework and to evaluate its potential contribution to biomechanics research, education, and applied movement sciences. Full article