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Racial disparities in electrical and structural cardiac adaptation among adolescent athletes:A systematic review and meta-analysis
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作者 Rasha Kaddoura Hassan Al-Tamimi Guido E Pieles 《World Journal of Cardiology》 2025年第11期140-150,共11页
BACKGROUND In pediatric and adolescent athletes,there is a lack of understanding about the impact of factors such as race on the structural or cardiovascular adaptations in response to exercise which may unnecessarily... BACKGROUND In pediatric and adolescent athletes,there is a lack of understanding about the impact of factors such as race on the structural or cardiovascular adaptations in response to exercise which may unnecessarily disqualify athletes from the competitive sport.We hypothesized that race has an impact on cardiac adaptions in non-adult athletes.AIM To explore the racial disparity in electrocardiographic(ECG)and echocardiographic(ECHO)parameters in healthy adolescent athletes.METHODS A comprehensive electronic systematic literature search using MEDLINE database was performed from inception to September 20,2024.Inclusion criteria included randomized or observational cohort studies that recruited adolescent competitive athletes in any sport discipline and compared between the Black and White races with an age range of 12-18 years.RESULTS Of 723 records that were identified by the literature search,seven studies(n=5036)were included.The mean age was 13.0-18.0 years old with male predominance.Black athletes had significantly longer PR interval[mean difference(MD)=17.49 millisecond,95% CI:11.70-23.29]and shorter QRS complex duration(MD=-7.35 millisecond,95% CI:-9.17 to-5.53)and corrected QT interval(MD=-4.95 millisecond,95% CI:-7.69 to-2.22)than the White athletes.Black athletes were approximately four times more likely to have first-degree atrioventricular(AV)block,inverted T wave,ST-segment elevation,and left atrium(LA)enlargement than their White counterparts.In terms of ECHO parameters,Black athletes had significantly greater septal wall thickness(MD=0.85 mm,95% CI:0.62-1.07),posterior wall thickness(MD=1.07 mm,95% CI:0.36-1.78),relative wall thickness(MD=0.03,95%CI:0.001-0.06),maximal wall thickness(MD=1.05 mm,95%CI:0.28-1.83),and LA diameter(MD=1.64 mm,95%CI:0.16-3.12).CONCLUSION Race has an impact on the ECG and ECHO parameters that reflect cardiac adaptations in adolescent athletes.Black athletes tend to have an increased prevalence of distinct ECG changes such as first-degree AV block and T-wave inversions compared with their White counterparts.Despite having thicker septal and posterior walls,the overall prevalence of left ventricular hypertrophy did not differ between the races. 展开更多
关键词 ADAPTATION athlete’s heart Atrial dilation Electrical remodeling Endurance athletes TEENAGE Ventricular hypertrophy
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钠冷快堆熔化事故不同DHX运行响应的ATHLET模拟
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作者 霍颖颖 杨清 +1 位作者 许巍 刘晓晶 《哈尔滨工业大学学报》 北大核心 2025年第12期276-282,共7页
钠冷快堆(SFR)作为一种先进的核反应堆,使用液态钠作为冷却剂,依靠快中子进行核裂变,具有非能动安全特性。但是,当发生严重事故时,可能会导致堆芯熔化。为提高SFR在严重事故下的安全响应性能,文中提出使用ATHLET程序对SFR在严重事故下... 钠冷快堆(SFR)作为一种先进的核反应堆,使用液态钠作为冷却剂,依靠快中子进行核裂变,具有非能动安全特性。但是,当发生严重事故时,可能会导致堆芯熔化。为提高SFR在严重事故下的安全响应性能,文中提出使用ATHLET程序对SFR在严重事故下钠池各位置的温度进行安全分析。首先,对SFR堆芯结构进行合理简化,在模型搭建基础上划分节点图。其次,采用ATHLET程序模拟计算SFR的堆芯熔化事故,输入熔融物衰变热与冷池/热池独立热交换器(DHX)功率等关键参数。最后,根据模拟结果分析了分别位于冷池/热池的4台DHX的不同运行状态对SFR主要区域热工参数的影响。结果表明:热池DHX的关闭会使下冷池与下腔室之间的流道出现逆流,下腔室下降段温度大幅升高,而冷池DHX的关闭工况会使SFR各部分区域冷却剂的温度都显著升高。相较之下,冷池失去一台DHX的运行对严重事故下的SFR更为危险,严重事故时应保证冷池的两台DHX都处于运行状态,及时排出堆芯熔化热量。综上,文中针对DHX在堆芯熔化事故下作用的研究结果能够为SFR结构设计优化和热工水力模型验证提供参考价值。 展开更多
关键词 钠冷快堆(SFR) athlet 安全分析 独立热交换器(DHX) 严重事故
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Are female athlete specific health considerations being assessed and addressed in preparticipation examinations?A scoping review and proposed framework
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作者 Jenna M.Schulz Lois Pohlod +2 位作者 Samantha Myers Jason Chung Jane S.Thornton 《Journal of Sport and Health Science》 2025年第2期149-158,共10页
Background:Preparticipation examinations(PPEs)are unstandardized screening tools routinely used to collect an athlete's baseline health information prior to the start of a new competitive season.However,many PPEs ... Background:Preparticipation examinations(PPEs)are unstandardized screening tools routinely used to collect an athlete's baseline health information prior to the start of a new competitive season.However,many PPEs include minimal and often nonspecific questions related to the health concerns of female athletes.A lack of female athlete specific health questions could result in missed red flags and subsequent injury or illness.As such,the objectives of this scoping review were to(a)determine what female athlete specific health questions currently exist in PPEs in the scientific literature to prevent injury and illness,and(b)map the results against the health domains outlined in the International Olympic Committee(IOC)consensus statement supplement on the female athlete.Methods:We searched Embase,Scopus,CINAHL,Medline Ovid,and SPORTDiscus from inception to December 2022.Any study with female athlete specific health PPE questions or recommendations for questions(i.e.,menstrual health,eating habits,musculoskeletal health,etc.)was included.Three reviewers independently screened titles and abstracts,followed by full text articles for eligibility and data extraction,with conflicts resolved by a third-party reviewer.Extracted data were summarized into 3 determined groupings.Results:Of the 1356 studies screened,41 were included in this study.Forty studies(98%)included questions/recommendations related to menstrual health.Thirty-one studies(76%)had questions/recommendations concerning disordered eating/eating habits.Twenty-four studies(59%)referred to body weight/image,and 16 studies(39%)referred to musculoskeletal health.No studies included questions on all IOC female athlete health domains.Conclusion:There is currently a gap in female athlete specific health content included in PPEs.A more comprehensive,standardized PPE with a focus on inclusion of female athlete specific health questions and considerations should be developed to improve health and optimal participation of female athletes around the world. 展开更多
关键词 FEMALE athletE Preparticipation Sport medicine SCREENING
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A strong athletic spirit
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作者 李玉莲 《疯狂英语(新读写)》 2025年第9期70-71,80,共3页
The athletic spirit goes beyond mere competition;it reflects the personal qualities that athletes embody both on and off the field.Central to this spirit is willpower,the inner strength that drives athletes to maintai... The athletic spirit goes beyond mere competition;it reflects the personal qualities that athletes embody both on and off the field.Central to this spirit is willpower,the inner strength that drives athletes to maintain rigorous training schedules and push their limits.This determination is essential for achieving excellence,especially when faced with challenges and setbacks. 展开更多
关键词 excellence CHALLENGES athletic spirit WILLPOWER training schedules setbacks
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Iron deficiency, supplementation, and sports performance in female athletes: A systematic review
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作者 Michael Pengelly Kate Pumpa +1 位作者 David Bruce Pyne Naroa Etxebarria 《Journal of Sport and Health Science》 2025年第3期83-95,共13页
Background:Iron facilitates key biological functions underpinning sports performance,and up to 60%of female athletes experience iron deficiency.However,the effects of iron deficiency on sports performance in female at... Background:Iron facilitates key biological functions underpinning sports performance,and up to 60%of female athletes experience iron deficiency.However,the effects of iron deficiency on sports performance in female athletes is unclear,as are the degree of benefits of iron supplementation(FeSup).This study characterizes the effects of iron deficiency and FeSup on sports performance in high-level female athletes.Methods:Searches of the electronic databases MEDLINE,SPORTDiscus,Web of Science,Scopus,and CINAHL were performed in July 2023.Studies were included that evaluated the effects of iron deficiency or FeSup on sports performance in high-level(maximal oxygen uptake(VO2max)>45 mL/kg/min,or trained>5 h/week)iron deficient(ID)(serum ferritin(sFer)<40 mg/L)female athletes.Studies were assessed using a modified Downs and Black Quality Assessment Checklist.Results:A total of 23 studies comprising 669 athletes(age range:13-47 years)across 16 sports were included in the review.Iron deficiency negatively affects endurance performance by 3%-4%.However,endurance performance improved by 2%-20%when ID athletes were treated with 100 mg/day of elemental iron for up to 56 days via oral supplementation,or bi-daily via parenteral administration over 8-10 days.ID nonanemic athletes with low sFer stores may be predisposed to reduced maximal aerobic capacity.However,maximal aerobic capacity improved by 6%-15%following 16 mg/day-100 mg/day of elemental iron for 36-126 days.Isokinetic strength and anaerobic power performance may be impeded(-23%to+4%)among ID athletes,but the effect of FeSup on anaerobic power varied markedly(-5%to+9%)following 100 mg/day of elemental iron over 42-56 days,or 100 mg of elemental iron bi-daily over 8-10 days.The quality of studies was moderate(77%),ranging from low(57%)to high(100%).Moststudies(n=18)contained group sizes-20 athletes,thus limiting the likelihood of detecting significant effects(statistical power>0.80).Conclusion:High-level ID female athletes experience a negative impact on endurance performance,which can be improved by supplementing with»100 mg of elemental iron per day or bi-daily.The decrements in other performance parameters characterizing a range of sports coincide with the severity of iron deficiency. 展开更多
关键词 ANEMIA Non-anemia Mineral deficiency WOMAN High-level athletes
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Arrhythmias and structural remodeling in lifelong and retired master endurance athletes
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作者 Paolo D'Ambrosio Jarne De Paepe +15 位作者 Kristel Janssens Amy M.Mitchell Stephanie J.Rowe Luke W.Spencer Tim Van Puyvelde Jan Bogaert Olivier Ghekiere Rik Pauwels Lieven Herbots Tomas Robyns Peter M.Kistler Jonathan M.Kalman Hein Heidbuchel Rik Willems Guido Claessen AndréLa Gerche 《Journal of Sport and Health Science》 2025年第5期19-30,共12页
Background:A greater prevalence of arrhythmias has been described in endurance athletes,but it remains unclear whether this risk persists after detraining.We aimed to evaluate the prevalence of arrhythmias and their r... Background:A greater prevalence of arrhythmias has been described in endurance athletes,but it remains unclear whether this risk persists after detraining.We aimed to evaluate the prevalence of arrhythmias and their relationship with cardiac remodeling in lifelong and retired master endurance athletes compared to non-athletic controls.Methods:We performed a cross-sectional analysis of observational studies that used echocardiography and cardiac magnetic resonance to detail cardiac structure and function,and Holter monitors to identify atrial and ventricular arrhythmias in 185 endurance athletes and 81 non-athletic controls aged≥40 years.Athletes were categorized as active lifelong(n=144)or retired(n=41)based on hours per week of high-intensity endurance exercise within 5 years of enrollment and validated by percentage of predicted maximal oxygen consumption(VO_(2max)).Athletes with overt cardiomyopathies,channelopathies,pre-excitation,and/or myocardial infarction were excluded.Results:Lifelong athletes(median age=55 years(interquartile range(IQR):46-62),79%male)were significantly fitter than retired athletes(median age=66 years(IQR:58-71),95%male)and controls(median age=53 years(IQR:48-60),96%male),respectively(predicted VO_(2max):131%±18%vs.99%±14%vs.98%±15%,p<0.001).Compared to controls,athletes in our cohort had a higher prevalence of atrial fibrillation((AF):32%vs.0%,p<0.001)and non-sustained ventricular tachycardia((NSVT):9%vs.1%,p=0.007).There was no difference in prevalence of any arrhythmia between lifelong and retired athletes.Lifelong athletes had larger ventricular volumes than retired athletes,who had ventricular volumes similar to controls(left ventricular end-diastolic volume indexed to body surface area(LVEDVi):101±20 m L/m^(2)vs.86±16 mL/m^(2)vs.94±18 mL/m^(2),p<0.001;right ventricular end-diastolic volume indexed to body surface area(RVEDVi):117±23 mL/m^(2)vs.101±19 mL/m^(2)vs.100±19 mL/m^(2),p<0.001).Athletes had more scar(40%vs.18%,p=0.002)and larger left atria(median volume=45m L/m^(2)(IQR:38-52)vs.31 mL/m^(2)(IQR:25-38),p<0.001)than controls,with no difference in atrial volumes and non-ischaemic scar between the athlete groups.Conclusion:Master endurance athletes have a higher prevalence of AF and NSVT than non-athletic controls.Whereas ventricular remodeling tends to reverse with detraining,the propensity to arrhythmias persists regardless of whether they are actively exercising or retired. 展开更多
关键词 athletES ARRHYTHMIAS Atrial fibrillation Non-sustained ventricular tachycardia DETRAINING
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The validity of automatic methods for estimating maturation stage in young athletes:A comparison of the Maturo smartphone application and sport science expert evaluations
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作者 Ximing Shang Jorge Arede +1 位作者 Pedro Couto Nuno Leite 《Journal of Sport and Health Science》 2025年第4期32-39,共8页
Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biologica... Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biological maturity and the limitations of existing testing methods, particularly in adolescent sports contexts, there is a pressing need for a non-invasive method that is convenient, accurate, and broadly applicable to monitor the biological maturity of adolescent athletes comprehensively. In response to this need, a maturity assessment method based on the smartphone application Maturo has been developed. This study evaluates the accuracy and validity of the Maturo software, an automated tool for estimating biological age and related maturation metrics.Methods: A sample of 103 actively training teenage athletes aged 9-17 years. The sample included 76 males(age = 11.74 ± 1.55 years, mean ±SD) and 27 females(age = 13.95 ± 1.40 years), all without medical conditions that might impact growth or development.Results: Compared to traditional expert evaluations, the intraclass correlation coefficients(ICCs) and Pearson correlation coefficients demonstrated reliable positive correlations and significant agreement between the Maturo software and expert methods across multiple metrics, such as biological age(ICC = 0.965, R = 0.97), corrected biological age(ICC = 0.973, R = 0.99), predicted adult height(ICC = 0.991, R = 0.99), and percentage of adult height achieved(ICC = 0.955, R = 0.97). The Bland-Altman plots provided additional evidence of the validity of the Maturo software estimations, showing low systematic error in most measures. The linear regression analysis produced excellent adjusted R2values: 0.95for biological age and 0.99 for anticipated adult height. The Maturo approach demonstrated a high level of dependability in classifying teenagers into groups based on their maturity status and timing. The κ coefficients of 0.93 for maturity status and 0.82 for maturity timing indicate a nearly perfect agreement with the expert technique.Conclusion: While the Maturo software's non-invasive nature, cost-effectiveness, and ease of use could make it a potential tool for regular monitoring of growth and maturation in young athletes, its promising results in assessing maturation should be interpreted with caution due to limitations such as sample size and demographic constraints. Further longitude research with larger and more diverse populations is needed to validate these preliminary findings and strengthen the evidence for its broader applicability. 展开更多
关键词 Maturation assessment Youth athletes Maturo software Biological maturation estimation ANTHROPOMETRY
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Effect of High-Intensity Interval Training on Muscle Strength Growth in Athletes
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作者 Yang Jiao 《Journal of Contemporary Educational Research》 2025年第10期408-414,共7页
High-intensity interval training(HIIT),a highly efficient and distinctive exercise format,has sparked growing academic interest in sports performance training.This article synthesizes theoretical and applied evidence ... High-intensity interval training(HIIT),a highly efficient and distinctive exercise format,has sparked growing academic interest in sports performance training.This article synthesizes theoretical and applied evidence to analyze mechanisms of HIIT in neuromuscular activation,hormonal responses,muscle fiber adaptation,and metabolic pathway effects.It focuses on its effectiveness in enhancing explosive power,maximum strength,and strength endurance,while also examining the integration of HIIT with traditional resistance training,periodized programming,and personalized prescription.Scientific implementation of HIIT can effectively diversify or even replace conventional strength training,not only offering positive directional changes for strength development but also introducing innovative approaches to sports performance training practices. 展开更多
关键词 High-intensity interval training Muscle strength athletES Intervention effect
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Goalie Phenomenon: Unveiling Hidden Health Conditions in Young Athletes
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作者 Jaber H.Jaradat Rawan Hamamreh Abdulqadir J.Nashwan 《Health Care Science》 2025年第6期424-426,共3页
1|Goalie Phenomenon The goalie phenomenon describes a group of health issues that may become apparent in children who prefer playing as goalkeepers.This preference might not only be about the excitement of the role bu... 1|Goalie Phenomenon The goalie phenomenon describes a group of health issues that may become apparent in children who prefer playing as goalkeepers.This preference might not only be about the excitement of the role but also as a coping mechanism for underlying health issues that make continuous running and high physical exertion challenging.The term highlights how certain positions in sports can sometimes obscure or reveal hidden health conditions,particularly among young athletes[1–3].To our knowledge,this is the first paper to formally introduce the term“Goalie phenomenon”in the literature exploring exerciseinduced asthma and sports role preferences in children. 展开更多
关键词 young athletes exercise induced asthma coping mechanism goalie phenomenon sports role preferences health conditions
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Effects of modified Yokoyama surgery combined with medial rectus muscle recession on esotropia in highly myopia athletes
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作者 Zi-Yang He Tan Cui +3 位作者 Zhi-Qi Cui Hui-Xia Yan Mei-Xuan Chen Hao Luo 《World Journal of Clinical Cases》 2025年第21期34-41,共8页
BACKGROUND Fixed esotropia in high myopia,characterized by irreversible inward ocular deviation and abduction limitation,presents unique therapeutic challenges for athletes requiring precise binocular coordination.The... BACKGROUND Fixed esotropia in high myopia,characterized by irreversible inward ocular deviation and abduction limitation,presents unique therapeutic challenges for athletes requiring precise binocular coordination.The combination of Yokoyama surgery and medial rectus muscle recession has been proposed as an advanced technique addresses both myopia-induced globe displacement and muscular imbalance offering potential advantages over conventional strabismus surgery in this population.AIM To investigate the effects of the modified Yokoyama surgery coupled with medial rectus muscle recession in restoring ocular motility and correcting esotropia among athletes with high myopia and fixed esotropia.METHODS A retrospective study analyzed 30 highly myopia athletes(57 eyes)with fixed esotropia treated at our hospital from January 2022 to April 2024.The participants were allocated into two groups based on the surgical method:The traditional group(n=15,29 eyes)received conventional strabismus surgery,and the combined group(n=15,28 eyes)underwent modified Yokoyama surgery in combination with medial rectus muscle recession.Eye movement improvement,esotropia alleviation,and complications were compared preoperatively and at 1,3,and 6 months post-treatment.RESULTS Both surgical groups exhibited similar baseline scores(traditional:-4.04±0.38 vs combined:-4.12±0.45,P>0.05),showing severe preoperative limitations in ocular motility.Following the intervention,the combined group achieved significantly better outcomes at both 1 month(combined:-2.25±0.28 vs traditional:-2.67±0.32)and 3 months(combined:-1.48±0.28 vs traditional:-1.76±0.43),with statistically significant improvements(P<0.05).However,by 6 months,no significant difference was observed between the two groups(combined:-0.93±0.13;traditional:-1.03±0.18;P>0.05).Prior to treatment,all patients in both groups exhibited a compensatory head posture(CHP).Following treatment,the incidence of CHP decreased to 6.67%in the combined group and 20.00%in the traditional group,both reductions being significant compared to pretreatment levels(P<0.05).Nevertheless,the difference in CHP incidence between the two groups after treatment was not significant(P>0.05).The rates of improvement in esotropia showed an increasing trend in both groups at 1 month(46.43%vs 34.48%),3 months(78.57%vs 51.728%),and 6 months(100.00%vs 89.66%)post-treatment.Notably,the combined group had a significantly higher improvement rate than the traditional group at the 3-month follow-up(P<0.05).No significant difference was observed in the esotropia improvement rates between the two groups at 1 and 6 months post-treatment(P>0.05).The combined group experienced slightly lower but not significant(combined group:0.00%vs traditional:3.45%)as opposed to the traditional group(3.45%;P>0.05).CONCLUSION The combination of modified Yokoyama surgery and medial rectus muscle recession provides effective and safe approach to improving in eye movement and esotropia in athletes with high myopia and fixed esotropia,offering reliable clinical benefits. 展开更多
关键词 High myopia with fixed esotropia athletE Eye movement Modified Yokoyama surgery Medial rectus muscle recession
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Feasibility of Using Optimal Control Theory and Training-Performance Model to Design Optimal Training Programs for Athletes
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作者 Yi Yang Che-Yu Lin 《Computer Modeling in Engineering & Sciences》 2025年第6期2767-2783,共17页
In order to help athletes optimize their performances in competitions while prevent overtraining and the risk of overuse injuries,it is important to develop science-based strategies for optimally designing training pr... In order to help athletes optimize their performances in competitions while prevent overtraining and the risk of overuse injuries,it is important to develop science-based strategies for optimally designing training programs.The purpose of the present study is to develop a novel method by the combined use of optimal control theory and a training-performance model for designing optimal training programs,with the hope of helping athletes achieve the best performance exactly on the competition day while properly manage training load during the training course for preventing overtraining.The training-performance model used in the proposed optimal control framework is a conceptual extension of the Banister impulse-response model that describes the dynamics of performance,training load(served as the control variable),fitness(the overall positive effects on performance),and fatigue(the overall negative effects on performance).The objective functional of the proposed optimal control framework is to maximize the fitness and minimize the fatigue on the competition day with the goal of maximizing the performance on the competition day while minimizing the cumulative training load during the training course.The Forward-Backward Sweep Method is used to solve the proposed optimal control framework to obtain the optimal solutions of performance,training load,fitness,and fatigue.The simulation results show that the performance on the competition day is higher while the cumulative training load during the training course is lower with using optimal control theory than those without,successfully showing the feasibility and benefits of using the proposed optimal control framework to design optimal training programs for helping athletes achieve the best performance exactly on the competition day while properly manage training load during the training course for preventing overtraining.The present feasibility study lays the foundation of the combined use of optimal control theory and training-performance models to design personalized optimal training programs in real applications in athletic training and sports science for helping athletes achieve the best performances in competitions while prevent overtraining and the risk of overuse injuries. 展开更多
关键词 Banister impulse-response model athletic training and performance coaching education physical fitness sports science computational and mathematical modeling
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Stress of the Off-Season May Be Greater for the Student-Athlete than during Competition: A Pilot Study
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作者 Jeannie D. DiClementi Anna Reese Tyler Borsa 《Journal of Behavioral and Brain Science》 2017年第7期304-310,共7页
We assessed 16 student-athletes in their first year of college on several dimensions, including severity of psychological and physical symptoms, mental health upset, academic concerns, suicidal tendencies, depressive ... We assessed 16 student-athletes in their first year of college on several dimensions, including severity of psychological and physical symptoms, mental health upset, academic concerns, suicidal tendencies, depressive outlook, anxiety and tension, attention difficulties, and alcohol abuse. We assessed half during their sports’ competition season and half during their off-season. Results pointed to increased perceived stress during the down time of off season. It may be that for student-athletes, the structure of competition season offsets the stress of competition, such that when the structure is removed or lessened, perceived stress increases. Implications of these data are discussed as well as plans for developing follow-up studies. 展开更多
关键词 COLLEGE Student-athletes athletICS and STRESS Millon COLLEGE Counseling Inventory Student-athlete Adjustment
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ATHLET程序的钠冷快堆应用扩展及其验证 被引量:4
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作者 周翀 Klaus Huber 程旭 《原子能科学技术》 EI CAS CSCD 北大核心 2013年第11期2053-2058,共6页
系统分析程序是对钠冷快堆的冷却剂回路系统进行全局模拟、瞬态及事故安全分析的重要工具。本工作对德国核设施与反应堆安全机构(GRS)开发的轻水堆最佳估算系统程序ATHLET进行修改,增加了钠的物性公式和传热关系式,将其适用范围扩展到... 系统分析程序是对钠冷快堆的冷却剂回路系统进行全局模拟、瞬态及事故安全分析的重要工具。本工作对德国核设施与反应堆安全机构(GRS)开发的轻水堆最佳估算系统程序ATHLET进行修改,增加了钠的物性公式和传热关系式,将其适用范围扩展到钠冷快堆。为验证修改过的ATHLET程序,对法国凤凰(Phenix)反应堆系统建模,并对其自然对流实验进行模拟,将计算结果与实验数据进行比较。结果显示,ATHLET程序的钠冷快堆应用扩展具有良好的适用性。 展开更多
关键词 钠冷快堆 athlet程序 自然对流
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ATHLET-SC程序的开发及适用性分析 被引量:6
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作者 周翀 刘晓晶 +1 位作者 杨燕华 程旭 《原子能科学技术》 EI CAS CSCD 北大核心 2009年第6期556-560,共5页
由于超临界水堆(SCWR)在系统简化、降低成本和提高热效率上的优势,SCWR的研究在全球范围内得到广泛关注。在众多有关超临界水堆的研发工作中,开发适用于SCWR的系统分析程序是进行SCWR系统设计和安全评估的关键技术难题之一。本工作基于... 由于超临界水堆(SCWR)在系统简化、降低成本和提高热效率上的优势,SCWR的研究在全球范围内得到广泛关注。在众多有关超临界水堆的研发工作中,开发适用于SCWR的系统分析程序是进行SCWR系统设计和安全评估的关键技术难题之一。本工作基于最佳估算系统分析程序ATHLET2.1A,增加了超临界热物性参数,开发出适用于SCWR的系统分析程序ATHLET-SC,将现有的ATH-LET程序扩展到超临界压力状态。为评估修改后的程序的适用性,建立了混合能谱超临界水堆堆芯模型,并对该模型进行了功率瞬态计算。此外,对1个简化的超临界水冷却回路进行了稳定性分析。计算结果表明:修改过的ATHLET程序(ATHLET-SC)对SCWR系统的模拟具有良好的适用性。 展开更多
关键词 超临界水堆 安全分析 athlet-SC程序
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Analysis of stress fractures in athletes based on our clinical experience 被引量:4
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作者 Jun Iwamoto Yoshihiro Sato +1 位作者 Tsuyoshi Takeda Hideo Matsumoto 《World Journal of Orthopedics》 2011年第1期7-12,共6页
AIM:To analyze stress fractures in athletes based on experience from our sports medicine clinic.METHODS:We investigated the association between stress fractures and age,sex,sports level,sports activity,and skeletal si... AIM:To analyze stress fractures in athletes based on experience from our sports medicine clinic.METHODS:We investigated the association between stress fractures and age,sex,sports level,sports activity,and skeletal site in athletes seen at our sports medicine clinic between September 1991 and April 2009.Stress fractures of the pars interarticularis were excluded from this analysis.RESULTS:During this period(18 years and 8 mo),14276 patients(9215 males and 5061 females)consulted our clinic because of sports-related injuries,and 263 patients(1.8%)[171 males(1.9%)and 92 females(1.8%)]sustained stress fractures.The average age of the patients with stress fractures was 20.2 years(range 10-46 years);112 patients(42.6%)were 15-19 years of age and 90(34.2%)were 20-24 years of age.Altogether,90 patients(34.2%)were active at a high recreational level and 173(65.8%)at a competitive level.The highest proportion of stress fractures was seen in basketball athletes(21.3%),followed by baseball(13.7%),track and field(11.4%),rowing(9.5%),soccer(8.4%),aerobics(5.3%),and classical ballet(4.9%).The most common sites of stress fractures in these patients were the tibia(44.1%),followed by the rib(14.1%),metatarsal bone(12.9%),ulnar olecranon(8.7%)and pelvis(8.4%).The sites of the stress fractures varied from sport to sport.The ulnar olecranon was the most common stress fracture site in baseball players,and the rib was the most common in rowers.Basketball and classical ballet athletes predominantly sustained stress fractures of the tibia and metatarsal bone.Track and field and soccer athletes predominantly sustained stress fractures of the tibia and pubic bone.Aerobics athletes predominantly sustained stress fractures of the tibia.Middle and long distance female runners who sustained multiple stress fractures had the female athlete triad.CONCLUSION:The results of this analysis showed that stress fractures were seen in high-level young athletes,with similar proportions for males and females,and that particular sports were associated with specific sites for stress fractures.Middle and long distance female runners who suffered from multiple stress fractures had the female athlete triad. 展开更多
关键词 athletES Bone MINERAL density Female athletE TRIAD Stress fracture VITAMIN D INSUFFICIENCY
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Visual efficiency among teenaged athletes and non-athletes
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作者 Rokiah Omar Yau Meng Kuan +2 位作者 Nurul Atikah Zuhairi Faudziah Abd Manan Victor Feizal Knight 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第9期1460-1464,共5页
AIM:To compare visual efficiency,specifically accommodation,vergence,and oculomotor functions among athletes and non-athletes.METHODS:A cross-sectional study on sports vision screening was used to evaluate the visua... AIM:To compare visual efficiency,specifically accommodation,vergence,and oculomotor functions among athletes and non-athletes.METHODS:A cross-sectional study on sports vision screening was used to evaluate the visual skills of 214elementary students(107 athletes,107 non-athletes),aged between 13 and 16y.The visual screening assessed visual parameters such as ocular motor alignment,accommodation,and vergence functions.RESULTS:Mean visual parameters were compared between age-group matched athletes(mean age14.82±0.98y)and non-athletes(mean age 15.00±1.04y).The refractive errors of all participants were corrected to maximal attainable best corrected visual acuity of log MAR0.0.Accommodation function assessment evaluated amplitude of accommodation and accommodation facility.Vergence functions measured the near point of convergence,vergence facility,and distance fusional vergence at break and recovery point.Ocular motor alignment was not statistically significant between both groups.Athletes had a statistically significant amplitude of accommodation for both the right eye(t=2.30,P=0.02)and the left eye(t=1.99,P=0.05).Conversely,non-athletes had better accommodation facility(t=-2.54,P=0.01)and nearpoint of convergence(t=4.39,P〈0.001)when compared to athletes.Vergence facility was found to be better among athletes(t=2.47,P=0.01).Nevertheless,non-athletes were significantly better for both distance negative and positive fusional vergence.CONCLUSION:Although the findings are still inconclusive as to whether athletes had superior visual skills as compared to non-athletes,it remains important to identify and elucidate the key visual skills needed by athletes in order for them to achieve higher performance in their sports. 展开更多
关键词 ACCOMMODATION PHORIA VERGENCE athletES non-athletes sports
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Injury and illness in short-course triathletes:A systematic review
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作者 Sara A.Guevara Melissa L.Crunkhorn +5 位作者 Michael Drew Gordon Waddington Julien D.Périard Naroa Etxebarria Liam A.Toohey Paula Charlton 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期172-185,共14页
Background:Determining the incidence and prevalence of injury and illness in short-course triathletes would improve understanding of their etiologies and therefore assist in the development and implementation of preve... Background:Determining the incidence and prevalence of injury and illness in short-course triathletes would improve understanding of their etiologies and therefore assist in the development and implementation of prevention strategies.This study synthesizes the existing evidence on the incidence and prevalence of injury and illness and summarizes reported injury or illness etiology and risk factors affecting short-course triathletes.Methods:This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Studies reporting health problems(injury and illness)in triathletes(all sexes,ages,and experience levels)training and/or competing in short-course distances were included.Six electronic databases(Cochrane Central Register of Controlled Trials,MEDLINE,Embase,APA PsychINFO,Web of Science Core Collection,and SPORTDiscus)were searched.Risk of bias was independently assessed by 2 reviewers using the Newcastle-Ottawa Quality Assessment Scale.Two authors independently completed data extraction.Results:The search yielded 7998 studies,with 42 studies eligible for inclusion.Twenty-three studies investigated injuries,24 studies investigated illnesses,and 5 studies investigated both injuries and illnesses.The injury incidence rate ranged 15.7-24.3 per 1000 athlete exposures,and the illness incidence rate ranged 1.8-13.1 per 1000 athlete days.Injury and illness prevalence ranged between 2%-15%and 6%-84%,respectively.Most injuries reported occurred during running(45%-92%),and the most frequently reported illnesses affected the gastrointestinal(7%-70%),cardiovascular(14%-59%),and respiratory systems(5%-60%).Conclusion:The most frequently reported health problems in short-course triathletes were:overuse and lower limb injuries associated with running;gastrointestinal illnesses and altered cardiac function,primarily attributable to environmental factors;and respiratory illness mostly caused by infection. 展开更多
关键词 athlete illnesses athletic injuries EPIDEMIOLOGY TRIATHLON
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Longitudinal trajectories of athlete burnout among young table tennis players: A 3-wave study
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作者 Guillaume Martinent Benoıt Louvet Jean-Claude Decret 《Journal of Sport and Health Science》 SCIE 2020年第4期367-375,共9页
Purpose:The purposes of this study were to examine the trajectories of athlete burnout across a 2-month period characterized by high physical,psychological,and social demands to explore(1)whether several subgroups of ... Purpose:The purposes of this study were to examine the trajectories of athlete burnout across a 2-month period characterized by high physical,psychological,and social demands to explore(1)whether several subgroups of athletes representing distinct burnout trajectories emerged from the analyses and(2)whether athlete burnout symptoms(reduced accomplishment,sport devaluation,and exhaustion)developed in tandem or whether some burnout dimensions predicted downstream changes in other dimensions(causal ordering model).Methods:One hundred and fifty-nine table tennis players in intensive training centers completed a self-reported athlete burnout measure across 3 time points within a 2-month period characterized by high demands.Data were analyzed through latent class growth analysis.Results:Results of latent class growth analysis showed 3 distinct trajectories for each athlete burnout dimension,indicating not only linear or quadratic change but also stability in longitudinal athlete burnout perceptions.Results also suggested that the 3 dimensions of athlete burnout did not develop in tandem.Rather,the likelihood of belonging to particular emerging trajectories of sport devaluation and physical/emotional exhaustion was significantly influenced by the athletes’perception of reduced accomplishment assessed at Time 1.Thus,reduced accomplishment predicted downstream changes in the 2 other athlete burnout dimensions.Conclusion:As a whole,these results highlighted that the multinomial heterogeneity in longitudinal athlete burnout symptoms needs to be accounted for in future research. 展开更多
关键词 athlete burnout Intensive training Latent class growth analyses Person-centered approach Table tennis Youth elite athletes
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ATHLET程序及其在低温供热堆中的应用 被引量:6
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作者 方京 周志伟 《核科学与工程》 CSCD 北大核心 2003年第1期91-95,共5页
ATHLET程序是德国核设施安全评审中心GRS开发的一个重要的反应堆热工水力学分析程序。它可分析除堆芯熔化事故之外的其他设计基准事故 ,可应用于美欧传统和先进的压水堆和沸水堆 ,原苏联设计的压水堆 (VVER)和石墨水冷堆 (RBMK) ,以及... ATHLET程序是德国核设施安全评审中心GRS开发的一个重要的反应堆热工水力学分析程序。它可分析除堆芯熔化事故之外的其他设计基准事故 ,可应用于美欧传统和先进的压水堆和沸水堆 ,原苏联设计的压水堆 (VVER)和石墨水冷堆 (RBMK) ,以及加拿大的CANDU堆等反应堆系统的热工分析。介绍了微机版ATHLET程序 ,并用它对 5MW低温供热堆自然循环稳态运行工况进行了计算 。 展开更多
关键词 低温供热堆 athlet程序 反应堆 热工水力学
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