Home  About us  Contact
 

Athletes

Distribution by Scientific Domains
Medical Sciences53%
Life Sciences19%
Chemistry9%
Psychology7%
Education5%
Humanities and Social Sciences2%
2 Other Domains5%
Distribution within Medical Sciences
Cardiovascular Disease30%
Allergy & Clinical Immunology9%
General & Internal Medicine5%
19 Other Subdomains46%

Kinds of Athletes

  • competitive athlete
  • elite athlete
  • elite endurance athlete
    		•
  • endurance athlete
  • female athlete
  • high school athlete
    		•
  • male athlete
  • older athlete
  • student athlete
    		•
  • young athlete

    • Terms modified by Athletes

  • athlete heart
    		•

    Selected Abstracts

    IDENTIFYING ATHLETES AT RISK OF HAMSTRING STRAINS AND HOW TO PROTECT THEM

    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2004
    U Proske
    SUMMARY 1.,One common soft-tissue injury in sports involving sprinting and kicking a ball is the hamstring strain. Strain injuries often occur while the contracting muscle is lengthened, an eccentric contraction. We have proposed that the microscopic damage to muscle fibres that routinely occurs after a period of unaccustomed eccentric exercise can lead to a more severe strain injury. 2.,An indicator of susceptibility for the damage from eccentric exercise is the optimum angle for torque. When this is at a short muscle length, the muscle is more prone to eccentric damage. It is known that subjects most at risk of a hamstring strain have a previous history of hamstring strains. By means of isokinetic dynamometry, we have measured the optimum angle for torque for nine athletes with a history of unilateral hamstring strains. We also measured optimum angles for 18 athletes with no previous history of strain injuries. It was found that mean optimum angle in the previously injured muscles was at a significantly shorter length than for the uninjured muscles of the other leg and for muscles of both legs in the uninjured group. This result suggests that previously injured muscles are more prone to eccentric damage and, therefore, according to our hypothesis, more prone to strain injuries than uninjured muscles. 3.,After a period of unaccustomed eccentric exercise, if the exercise is repeated 1 week later, there is much less evidence of damage because the muscle has undergone an adaptation process that protects it against further damage. We propose that for athletes considered at risk of a hamstring strain, as indicated by the optimum angle for torque, a regular programme of mild eccentric exercise should be undertaken. This approach seems to work because evidence from a group of athletes who have implemented such a programme shows a significant reduction in the incidence of hamstring strains. [source]

    RESTING METABOLIC RATE AND POST-PRANDIAL THERMOGENESIS BY LEVEL OF AEROBIC POWER IN OLDER ATHLETES

    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 4 2004
    Alessio Sullo
    SUMMARY 1.,The aim of the present study was to evaluate the resting metabolic rate (RMR) and thermogenic effect of a meal (TEM) in older athletes. 2.,Eighteen older male volunteers were divided into three groups according to their aerobic power related to fat-free mass (FFM) as follows: (i) group I, high aerobic power (Vo2max > 70 mL/kg FFM per min); (ii) group II, moderate aerobic power (Vo2max = 55,70 mL/kg FFM per min); and (iii) group III, low aerobic power (Vo2max < 55 mL/kg FFM per min). 3.,The RMR values, covariated for FFM using analysis of covariance (ancova), were higher in group I (mean (±SEM) 1.09 ± 0.04 kcal/min) than in groups II and III (0.99 ± 0.05 and 0.91 ± 0.03 kcal/min, respectively). Group I had a tendency for higher mean TEM values compared with the other groups, but the differences were not statistically significant for absolute or percentage values. 4.,Master endurance athletes with high aerobic power exhibit a higher RMR than master endurance athletes of similar age and body composition but with lower aerobic power. [source]

    Echocardiographic Parameters in Athlete and Nonathlete Offspring of Hypertensive Parents

    ECHOCARDIOGRAPHY, Issue 1 2008
    Patrícia Horváth M.D.
    Background: According to several reports, some cardiovascular signs of hypertension (left ventricular [LV] hypertrophy, impaired diastolic filling) can be found in the normotensive offspring of hypertensive parents. It is also well known that regular physical exercise decreases the risk of hypertension. Aim: The aim of the present study is to determine whether or not regular physical training influences these early hypertensive traits in the offspring of hypertensive parents. Methods: Echocardiographic data of 215 (144 males, 71 females) 22- to 35-year-old nonathlete and athlete offspring of hypertensive (positive family history, FH+) and normotensive parents (negative family history, FH,) were compared in a cross-sectional design. Results: In the nonathlete FH+ males and females, LV dimensions were not larger than in the FH, subjects. The E/A quotient was lower in the FH+ subjects in both genders. Absolute and heart rate adjusted isovolumetric relaxation times were slightly longer in the FH+ men than in their FH, peers. No differences were seen between athlete FH, and FH+ subjects. Conclusion: Regular physical exercise decreases the incidence of the adverse cardiac signs, which can be associated with hypertension in the normotensive offspring of hypertensive parents. [source]

    Ionic Mechanisms and Vectorial Model of Early Repolarization Pattern in the Surface Electrocardiogram of the Athlete

    ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2008
    Eduardo C. Barbosa M.D.
    Background: The electrocardiogram (ECG) of the athlete displays particular characteristics as a consequence of both electrophysiological and autonomic remodeling of the heart that follows continued physical training. However, doubts persist on how these changes directly interact during ventricular activation and repolarization ultimately affecting surface ECG waveforms in athletes. Objective: This article considers an in deep rationale for the electrocardiographic pattern known as early repolarization based on both electrophysiological mechanisms at cellular level and the vectorial theory of the cardiac activation. Methods: The mechanism by which the autonomic remodeling influences the cardiac electrical activation is reviewed and an insight model of the ventricular repolarization based on ionic models and the vectorial theory of the cardiac activation is proposed. Results: Considering the underlying processes related to ventricular electrical remodeling, we propose that, in athletes' heart: 1) vagal modulation increases regional electrophysiological differences in action potential phases 1 and 2 amplitudes, thus enhancing a voltage gradient between epicardial and endocardial fibers; 2) this gradient affects depolarization and repolarization timing sequences; 3) repolarization wave front starts earlier on ventricular wall and partially overcomes the end of depolarization causing an upward displacement of the J-point, ST segment elevation, and inscription of magnified T-waves amplitudes leading to characteristic surface ECG waveform patterns. Conclusions: In athletes, the association between epicardial to endocardial electrophysiological differences and early repolarization ECG pattern can be demonstrated by the vectorial theory of the ventricular activation and repolarization. [source]

    "Supranormal" Cardiac Function in Athletes Related to Better Arterial and Endothelial Function

    ECHOCARDIOGRAPHY, Issue 6 2010
    Maria Florescu M.D.
    Objective: Athlete's heart is associated with left ventricular (LV) hypertrophy (LVH), and "supranormal" cardiac function, suggesting that this is a physiological process. Hypertrophy alone cannot explain increase in cardiac function, therefore, other mechanisms, such as better ventriculo-arterial coupling might be involved. Methods: We studied 60 male (21 ± 3 years) subjects: 27 endurance athletes, and a control group of 33 age-matched sedentary subjects. We assessed global systolic and diastolic LV function, short- and long-axis myocardial velocities, arterial structure and function and ventriculo-arterial coupling, endothelial function by flow-mediated dilatation, and amino-terminal pro-brain natriuretic peptide (NT-proBNP) and biological markers of myocardial fibrosis and of oxidative stress. Results: Athletes had "supranormal" LV longitudinal function (12.4 ± 1.0 vs 10.1 ± 1.4 cm/s for longitudinal systolic velocity, and 17.4 ± 2.6 vs 15.1 ± 2.4 cm/s for longitudinal early diastolic velocity, both P < 0.01), whereas ejection fraction and short-axis function were similar to controls. Meanwhile, they had better endothelial function (16.7 ± 7.0 vs 13.3 ± 5.3%, P < 0.05) and lower arterial stiffness (pulse wave velocity 7.1 ± 0.6 vs 8.8 ± 1.1 m/s, P = 0.0001), related to lower oxidative stress (0.259 ± 0.71 vs 0.428 ± 0.88 nmol/mL, P = 0.0001), with improved ventriculo-arterial coupling (37.1 ± 21.5 vs 15.5 ± 13.4 mmHg.m/s3× 103, P = 0.0001). NT-proBNP and markers of myocardial fibrosis were not different from controls. LV longitudinal function was directly related to ventriculo-arterial coupling, and inversely related to arterial stiffness and to oxidative stress. Conclusions: "Supranormal" cardiac function in athletes is due to better endothelial and arterial function, related to lower oxidative stress, with optimized ventriculo-arterial coupling; athlete's heart is purely a physiological phenomenon, associated with "supranormal" cardiac function, and there are no markers of myocardial fibrosis. (Echocardiography 2010;27:659-667) [source]

    Right Ventricular Adaptations Along with Left Ventricular Remodeling in Older Athletes

    ECHOCARDIOGRAPHY, Issue 3 2009
    Oner Ozdogan M.D.
    Background: Afterload changes and anatomic interaction between the ventricles cause right ventricle (RV) adaptation along with left ventricle (LV) remodeling. This study was designed to evaluate RV adaptations along with LV remodeling and to determine the effect of aging on both ventricles in a population of older athletes. Methods: Echocardiographic characteristics of 48 endurance trained older athletes were examined by tissue Doppler imaging (TDI) and integrated backscatter (IBS). Results: Mean LV mass index was calculated as 107.8±17.0 g/m2. Twenty-two athletes were > 55 years old. Age was found to be a risk factor for diastolic dysfunction regarding lateral TDI velocities (Em < Am) (r = 0.385, P < 0.001). RV long-axis (LAX) diameters were associated with LA volumes and LV masses (r = 0.380, P < 0.01 and r = 0.307, P < 0.05). RV LAX diameters were correlated with RV TDI E-wave (r =,0.285, P < 0.05), RV LAX average, and peak IBS values (r = 0.36, P < 0.05 and r = 0.348, P < 0.05). Conclusions: TDI and IBS are applicable methods to evaluate the relationship between the two ventricles in athletes' heart. Increased RV LAX IBS values indicate increased LV mass and LA volume as a result of RV changes along with LV remodeling. Our data suggest that RV TDI E-wave and average RV IBS values reflect cardiac adaptations of both RV and LV in older athletes. [source]

    Relationship between Relative Aerobic Power and Echocardiographic Characteristics in Male Athletes

    ECHOCARDIOGRAPHY, Issue 9 2007
    Zsuzsanna Kneffel M.Ed.
    The relationship between relative aerobic power (rel.VO2max) as a generally accepted indicator of endurance capacity and certain characteristics of the athlete's heart, such as body-size related (relative) left ventricular (LV) diastolic wall thickness (WTd), internal diameter (LVIDd), muscle mass (MM), WTd/IDd, heart rate (HR), fractional shortening (FS) and E/A ratio, were investigated in 346 young males (18,35 years, 291 athletes of various events and 55 nonathletic control subjects). Rel.VO2max was measured by spiroergometry; cardiac characteristics were determined by two-dimensionally guided M-mode and Doppler-echocardiography. When the groups were pooled, correlation of rel.VO2max with the cardiac parameters was significant: LVMM·BSA,1.5= 0.413, LVWTd·BSA,0.5= 0.327, LVIDd·BSA,0.5= 0.292, HR =,0.434, E/A = 0.272 (P < 0.001), but no significant relationship was seen with FS and WTd/IDd. In the endurance trained group, rel. VO2max correlated significantly with LVMM·BSA,1.5, LVWT·BSA,0.5, HR, and E/A, in the ballgame players with LVMM·BSA,1.5, LVWT·BSA,0.5, and E/A, in the power-and-sprint event athletes with HR and E/A. In the control group, no significant relationship was observed. Results indicate that in athletes having higher endurance capacity maximal oxygen consumption depends largely on cardiac condition, while in athletes with a lower endurance capacity it can be limited by peripheral conditions. [source]

    Echocardiographic Doppler Evaluation of Left Ventricular Diastolic Filling in Older, Highly Trained Male Endurance Athletes

    ECHOCARDIOGRAPHY, Issue 1 2000
    PETER R. JUNGBLUT M.D.
    Previously published data have suggested that endurance training does not retard the normative aging impairment of early left ventricular diastolic filling (LVDF). Those studies, suggesting no effect of exercise training, have not examined highly trained endurance athletes or their LVDF responses after exercise. We therefore compared LVDF characteristics in a group of older highly trained endurance athletes (n= 12, mean age 69 years, range 65,75) and a group of sedentary control subjects (n= 12, mean age 69 years, range 65,73) with no cardiovascular disease. For all subjects, M-mode and Doppler echocardiographic data were obtained at rest. After baseline studies, subjects underwent graded, maximal cardiopulmonary treadmill exercise testing using a modified Balke protocol. Breath-by-breath respiratory gas analysis and peak exercise oxygen consumption (VO2max) measurements were obtained. Immediately after exercise and at 3,6 minutes into recovery, repeat Doppler echocardiographic data were obtained for determination of LVDF parameters. VO2max (44 ± 6.3 vs 27 ± 4.2 mllkglmin, P< 0.001), oxygen consumption at anaerobic threshold (35 ± 5.4 vs 24 ± 3.8 mllkglmin, P< 0.001), exercise duration (24 ± 3 vs 12 ± 6 minutes, P< 0.001), and left ventricular mass index (61 ± 13 vs 51 ± 7.8 kglm2, P< 0.05) were greater in endurance athletes than in sedentary control subjects, whereas body mass index was lower (22 ± 1.7 vs 26 ± 3.4 kglm2, P< 0.001). No differences in any of the LVDF characteristics were observed between the groups with the exception of a trend toward a lower atrial filling fraction at rest in the endurance athlete group versus the control subjects (P= 0.07). High-intensity endurance exercise training promotes exceptional peak exercise oxygen consumption and cardiovascular stamina but does not appear to alter normative aging effects on left ventricular diastolic function. (ECHOCARDIOGRAPHY, Volume 17, January 2000) [source]

    ACE and angiotensinogen gene genotypes and left ventricular mass in athletes

    EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 10 2001
    F. Diet
    Background Genetic factors may be important in modifying heart size due to long-term athletic training. The significance of polymorphisms of genes of the renin,angiotensin system in myocardial mass in a population of athletes participating in different disciplines is not known. Methods The angiotensin I-converting enzyme gene insertion/deletion (I/D) polymorphism, angiotensinogen gene M235T polymorphism and angiotensin II type 1 receptor gene A1166C polymorphism were determined in 83 male Caucasian endurance athletes and associated with left ventricular mass. Results No association with left ventricular mass was found for the polymorphisms of angiotensin I-converting enzyme gene I/D, angiotensinogen gene M235T and angiotensin II type 1 gene A1166C when studied separately. However, combined analysis of the angiotensin I-converting enzyme gene I/D polymorphism and angiotensinogen gene M235T polymorphism genotypes suggested an association with left ventricular mass (g m,2) (P = 0·023). Athletes with the angiotensin I-converting enzyme gene DD/angiotensinogen gene TT genotype combination had greater left ventricular mass compared with all other genotype combinations (179·8 ± 26·1 g m,2 vs. 145·2 ± 27·3 g m,2, P = 0·003). Conclusions These results suggest an association of combined angiotensin I-converting enzyme gene I/D polymorphism genotypes, and angiotensinogen gene M235T polymorphism genotypes with left ventricular hypertrophy due to long-term athletic training. A synergistic effect of angiotensin I-converting enzyme gene DD genotype and angiotensinogen gene TT genotype on left ventricular mass in endurance athletes appears to occur. [source]

    Nutritional Assessment of Athletes by J. A. Driskell and I. Wolinsky

    EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2003
    Arthur D. Stewart
    No abstract is available for this article. [source]

    Acute Hypervolaemia Improves Arterial Oxygen Pressure in Athletes with Exercise-Induced Hypoxaemia

    EXPERIMENTAL PHYSIOLOGY, Issue 4 2003
    Gerald S. Zavorsky
    The aim of this study was to determine the effect of acute plasma volume expansion on arterial blood-gas status during 6.5 min strenuous cycling exercise comparing six athletes with and six athletes without exercise-induced arterial hypoxaemia (EIAH). We hypothesized that plasma volume expansion could improve arterial oxygen pressure in a homogeneous sample of athletes - those with EIAH. In this paper we have extended the analysis and results of our recently published surprising findings that lengthening cardiopulmonary transit time did not improve arterial blood-gas status in a heterogeneous sample of endurance cyclists. One 500 ml bag of 10% Pentastarch (infusion condition) or 60 ml 0.9% saline (placebo) was infused prior to exercise in a randomized, double-blind fashion on two different days. Power output, cardiac output, oxygen consumption and arterial blood gases were measured during strenuous exercise. Cardiac output and oxygen consumption were not affected by acute hypervolaemia. There were group × condition interaction effects for arterial oxygen pressure and alveolar-arterial oxygen pressure difference, suggesting that those with hypoxaemia experienced improved arterial oxygen pressure (+4 mmHg) and lower alveolar-arterial oxygen pressure difference (-2 mmHg) with infusion. In conclusion, acute hypervolaemia improves blood-gas status in athletes with EIAH. The impairment of gas exchange occurs within the first minute of exercise, and is not impaired further throughout the remaining duration of exercise. This suggests that arterial oxygen pressure is only minimally mediated by cardiac output. [source]

    Radiofrequency Catheter Ablation of Atrial Fibrillation in Athletes Referred for Disabling Symptoms Preventing Usual Training Schedule and Sport Competition

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2008
    FRANCESCO FURLANELLO M.D.
    Introduction: Atrial fibrillation (AF) may occasionally affect athletes by impairing their ability to compete, and leading to noneligibility at prequalification screening. The impact of catheter ablation (CA) in restoring full competitive activity of athletes affected by AF is not known. The aim of our study was to investigate the effectiveness of CA of idiopathic AF in athletes with palpitations impairing physical performance and compromising eligibility for competitive activities. Methods and Results: Twenty consecutive competitive athletes (all males; 44.4 ± 13.0 years) with disabling palpitations on the basis of idiopathic drug-refractory AF underwent 46 procedures (2.3 ± 0.4 per patient) according to a prospectively designed multiprocedural CA approach that consolidates pulmonary veins (PV) isolation through subsequent steps. Preablation, effort-induced AF could be documented in 13 patients (65%) during stress ECG and significantly reduced maximal effort capacity (176 ± 21 W), as compared with patients with no AF during effort (207 ± 43 W, P < 0.05). At the end of CA protocol, which also included ablation of atrial flutter (AFL) in 7 patients, 18 (90.0%) patients were free of AF and two (10.0%) reported short-lasting (minutes) episodes of palpitations during 36.1 ± 12.7 months follow-up. Compared with preablation, postablation maximal exercise capacity significantly improved (from 183 ± 32 to 218 ± 20 W, P < 0.02). All baseline quality of life (QoL) parameters pertinent to physical activity significantly improved (P < 0.05) at the end of CA protocol. All athletes obtained reeligibility and could effectively reinitiate sport activity. Conclusions: AF, alone or in combination with AFL, may significantly impair maximal effort capacity thereby limiting competitive performance. Multiple PV isolation proved very effective in these patients to restore full competitive activity and allow reeligibility. [source]

    Effects of chlorine and exercise on the unified airway in adolescent elite Scottish swimmers

    ALLERGY, Issue 2 2010
    K. L. Clearie
    To cite this article: Clearie KL, Vaidyanathan S, Williamson PA, Goudie A, Short P, Schembri S, Lipworth BJ. Effects of chlorine and exercise on the unified airway in adolescent elite Scottish swimmers. Abstract Background:, Chlorine metabolites and high training load may produce exercise-induced bronchospasm (EIB) in elite swimmers. The aim of this study was to assess the combined effects of chlorine and exercise on the unified airway of adolescent elite swimmers. Methods:, The Scottish Midlands District squad were assessed during an indoor pool session at the National Swimming Academy. Athletes trained at least 8 h per week. Subjects underwent tidal (TNO) and nasal (NNO) exhaled NO and peak nasal inspiratory flow (PNIF) pre and post a 2 h session. A physiological exercise challenge assessed EIB in n = 36 swimmers (>10% fall in forced expiratory volume in 1 s (FEV1)). Results:, Combined and free chlorine levels (mg/l) were 1.66 and 0.3 respectively. n = 36 swimmers (mean age 13.3 years) were assessed: n = 8 (22%) had known asthma; n = 13 (36%) had a positive physiological challenge; 18 (50%) complained of symptoms suggestive of EIB. n = 10/28 (36%) who did not have asthma were found to have a positive exercise challenge. There was no significant association between reported exercise symptoms and positive exercise test. There was no significant change in TNO or NNO for pre vs postexposure, irrespective of asthma diagnosis or AHR. n = 15 (42%) swimmers complained of worsening nasal symptoms postexposure, but only n = 7 (14%) had a demonstrable fall in PNIF (mean 33 l/min). No significant association was found between PNIF and symptoms. Conclusions:, Combined exposure to chlorine and exercise did not affect surrogate markers of inflammation in the unified airway. There was a high prevalence of undiagnosed EIB. [source]

    How College Affects Student Athletes

    NEW DIRECTIONS FOR STUDENT SERVICES, Issue 93 2001
    Mary F. Howard-Hamilton
    This chapter applies psychosocial and cognitive developmental theories to student athletes. [source]

    Advising and Counseling Student Athletes

    NEW DIRECTIONS FOR STUDENT SERVICES, Issue 93 2001
    Elizabeth Broughton
    The importance of counseling and advising services for student athletes is explained. [source]

    Female Student Athletes and Student Athletes of Color

    NEW DIRECTIONS FOR STUDENT SERVICES, Issue 93 2001
    Dawn R. Person
    The authors focus on policies that support student athletes of color and female student athletes. [source]

    Antioxidant Requirements of Endurance Athletes: Implications for Health

    NUTRITION REVIEWS, Issue 3 2006
    Sarah L. Williams BSc (Hons)
    This review discusses studies investigating the effects of antioxidant supplementation on exercise-induced oxidative stress with a focus on the health implications. The aim is to determine antioxidant requirements for endurance athletes. Overall, differences in methodology make it difficult to compare the relatively small number of published studies on this topic. The types of studies needed to more adequately assess the health effects of antioxidant supplements in athletes (long-term interventions with hard end points) have not been done. Therefore, there is currently insufficient evidence to recommend antioxidant supplements for endurance athletes. [source]

    School-based promotion of fruit and vegetable consumption in multiculturally diverse, urban schools

    PSYCHOLOGY IN THE SCHOOLS, Issue 1 2008
    Jessica Blom-Hoffman
    Rates of childhood overweight, have reached epidemic proportions (U.S. Department of Health and Human Services, 2001), and schools have been called on to play a role in the prevention of this medical condition. This article describes a multiyear health promotion effort,the Athletes in Service fruit and vegetable (F&V) promotion program,which is based on social learning theory for urban, elementary school children in kindergarten through third grade. Children participate in the program for a period of 3 years. The goals of the program are to increase opportunities for children to be more physically active during the school day and to help students increase their F&V consumption. This article describes the F&V promotion components of the program that were implemented in year 1, including implementation integrity and treatment acceptability data. Year 1 evaluation data demonstrated that the program is acceptable from the perspective of school staff and was implemented by school staff with high levels of integrity. Hallmarks of the program's successful implementation and high acceptability include (a) having a school-based program champion; (b) designing the program to include low-cost, attractive, interactive materials; (c) including many school staff members to facilitate a culture of healthy eating in the school; and (d) spreading out implementation responsibilities among the multiple staff members so that each individual's involvement is time efficient. © 2007 Wiley Periodicals, Inc. [source]

    T-Wave Variability Detects Abnormalities in Ventricular Repolarization: A Prospective Study Comparing Healthy Persons and Olympic Athletes

    ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2009
    Lara Heinz M.D.
    Background: Sudden cardiac death in athletes is more common than in the general population. Routine screening procedures are performed to identify competitors at risk. A new Holter-based parameter analyzes variation of the ventricular repolarization (TVar). The aim of this study was to evaluate differences in electrocardiogram (ECG), Echo, and Holter (H) in competitive athletes compared to a healthy control group consisting of medical students (MS). Methods: A total of 40 athletes (19 females, Olympic team, Luxembourg) and 40 MS (22 females) were examined by means of a resting ECG, treadmill exercise (TE), echocardiogram (Echo), as well as H recordings during a routine screening visit. To analyze TVar, a 20-minute H recording at rest (sampling rate 1000 per second) was performed. Moreover, heart rate variability (HRV) as well as HR turbulence (HRT) was computed. Results: No differences in demographic variables were detected. Quantification of HRV detected a significant increase in the vagal component of autonomic cardiac modulation. In contrast, no differences for HRT were found. Echo parameter demonstrated a thicker septal wall without differences of the posterior wall. TVar values were normal in range, but did differ significantly between the two groups. No correlation between TVar and echo as well as Holter parameters was detected. Conclusions: TVar was able to demonstrate significant differences in terms of alterations of ventricular activation. This might indicate an early change of myocardial repolarization representing a substrate for life-threatening arrhythmia. Larger studies on the predictive value of TVar including follow-up are necessary to confirm this preliminary finding. [source]

    Short QT Interval: A Novel Predictor of Androgen Abuse in Strength Trained Athletes

    ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2009
    Mohammad Ali Babaee Bigi M.D.
    Objectives: To find the relationship between anabolic androgenic steroids (AAS) using and QT interval in athletes. Methods: Between January 1, 2005 and May 31, 2007, we examined QTc interval duration in 165 consecutive male professional bodybuilders [age: 32.1 ± 4.6 years]. Of these, 79 were AAS users. The control group included 90 sedentary age and gender matched subjects [none of them were AAS users]. Results: The QTc interval of AAS abusing bodybuilders was significantly shorter compared with QTc interval in AAS-free bodybuilders and control group. Short QTc interval (,380 ms) was an independent predictor of AAS abusing in the multivariate analysis. Conclusions: To the best of our knowledge, there is no published report regarding electrocardiographic diagnosis and screening of AAS abusing athletes. In the present study, we present an easy and applicable method to screen and diagnose AAS abusing among professional bodybuilders. In the presence of QTc interval , 380 ms in a bodybuilder, one would predict AAS abusing with 83% sensitivity and 88% specificity. [source]

    T-Wave Alternans and Ventricular Arrhythmias in Athletes: Usefulness of Follow-up Updates

    ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2009
    F.E.S.C., Giuseppe Inama M.D.
    No abstract is available for this article. [source]

    Epidemiology of Lower Extremity Injuries among U.S. High School Athletes

    ACADEMIC EMERGENCY MEDICINE, Issue 7 2007
    William G. Fernandez MD
    Objectives:Despite the health benefits of organized sports, high school athletes are at risk for lower extremity sports-related injuries (LESRIs). The authors documented the epidemiology of LESRIs among U.S. high school athletes. Methods:Via two-stage sampling, 100 U.S. high schools were randomly selected. During the 2005 school year, LESRIs in nine sports were reported: boys' baseball, football, and wrestling; girls' softball and volleyball; and boys' and girls' basketball and soccer. The authors calculated rates as the ratio of LESRIs to the number of athlete exposures. National estimates were generated by assigning injuries a sample weight based on the inverse probability of the school's selection into the study. Results:Among high school athletes in 2005, 2,298 of 4,350 injuries (52.8%) were LESRIs. This represents an estimated 807,222 LESRIs in U.S. high school athletes in nine sports (1.33/1,000 athlete exposures). Football had the highest LESRI rate for boys (2.01/1,000) and soccer the highest for girls (1.59/1,000). Leading diagnoses were sprains (50%), strains (17%), contusions (12%), and fractures (5%). The ankle (40%), knee (25%), and thigh (14%) were most frequently injured. Fractures occurred most often in the ankle (42%), lower leg (29%), or foot (18%). Girls with ligamentous knee injuries required surgery twice as often as boys (67% vs. 35%; p < 0.01). Girls had 1.5 times the proportion of season-ending LESRIs of boys (12.5% vs. 8%; p < 0.01). Conclusions:While LESRIs occur commonly in high school athletes, team- and gender-specific patterns exist. Emergency department staff will likely encounter such injuries. To optimize prevention strategies, ongoing surveillance is needed. [source]

    Electrocardiographic Abnormalities in Young Athletes with Mitral Valve Prolapse

    CLINICAL CARDIOLOGY, Issue 8 2009
    oskot MD, yna Markiewicz-
    Background Mitral valve prolapse (MVP) is the most common primary valvular abnormality in a young population. In some individuals, MVP is silent or associated with palpitations, dizziness, chest pain, and abnormal electrocardiogram (ECG) repolarization with or without ventricular arrhythmias. Hypothesis The aim of the present study was to assess the occurrence of the clinical and electrocardiographic abnormalities in young athletes with silent MVP. Methods A group of 10 children, who have been sport training intensively, with preparticipation silent MVP were examined for symptoms and/or ECG abnormalities. The diagnosis of MVP was made by echocardiography. Results Three athletes were asymptomatic at initial presentation. The other 7 athletes presented with symptoms. The QTc intervals > 440 msec were recorded in 2 athletes (1 with syncope). Abnormal ECG repolarization was found in 7 athletes (4 athletes were symptomatic and 3 were asymptomatic). A large variety of T-waves was registered in athletes who presented with symptoms. In asymptomatic athletes, the tall and flat T-waves were recorded. Conclusions Young athletes with MVP are often predisposed to electrocardiographic abnormalities of ventricular repolarization, which requires annual cardiologic evaluation. Copyright © 2009 Wiley Periodicals, Inc. [source]

    Determination of 13C/12C ratios of urinary excreted boldenone and its main metabolite 5,-androst-1-en-17,-ol-3-one

    DRUG TESTING AND ANALYSIS, Issue 5 2010
    Thomas Piper
    Abstract Boldenone (androsta,1,4,dien,17,,ol,3,one, Bo) is an anabolic steroid known to have been used in cattle breeding or equine sport as a doping agent for many years. Although not clinically approved for human application, Bo or its main metabolite 5,-androst-1-en-17,-ol-3-one (BM1) were detected in several doping control samples. For more than 15 years the possibility of endogenous Bo production in human beings has been discussed. This is a challenging issue for doping control laboratories as Bo belongs to the list of prohibited substances of the World Anti-Doping Agency and therefore the chance for false positive testing is significant. By GC/C/IRMS (gas chromatography/combustion/isotope ratio mass spectrometry) it should be possible to analyze the 13C/12C ratio of either Bo or BM1 and to distinguish whether their source is endogenous or exogenous. Therefore a method was developed to determine the 13C/12C ratios of Bo, BM1, pregnanediol, androsterone, etiocholanolone, and testosterone from a single urine specimen. The validity of the method was ensured by repeated processing of urine fortified with 2,50 ng/mL Bo and BM1. The specificity of the method was ensured by gas chromatography/mass spectrometry determinations. Out of 23 samples investigated throughout the last four years, 11 showed 13C/12C ratios of Bo or BM1 inconsistent with an exogenous origin. Two of these samples were collected from the same athlete within a one-month interval, strongly indicating the chance of endogenous Bo production by this athlete. Copyright © 2010 John Wiley & Sons, Ltd. [source]

    ,And the beat goes on' The cardiac conduction system: the wiring system of the heart

    EXPERIMENTAL PHYSIOLOGY, Issue 10 2009
    Mark R. Boyett
    The cardiac conduction system (CCS), consisting of the sino-atrial node, atrioventricular node and His,Purkinje system, is responsible for the initiation and co-ordination of the heart beat. In the last decade, our understanding of the CCS has been transformed. Immunohistochemistry, used in conjunction with anatomical techniques, has transformed our understanding of its anatomy; arguably, we now understand the position of the sino-atrial node (not the same as in medical textbooks), and our new understanding of the atrioventricular node anatomy means that we can compute its physiological and pathophysiological behaviour. Ion channel expression in the CCS has been shown to be fundamentally different from that in the working myocardium. Dysfunction of the CCS has previously been attributed to fibrosis, but it is now clear that remodelling of ion channels plays an important role in dysfunction during ageing, heart failure and atrial fibrillation. Differences in ion channel expression may even be responsible for the bradycardia in the athlete and differences in heart rate among different species (such as humans and mice). Recent work has highlighted less well-known components of the CCS, including tricuspid, mitral and aortic rings and even a third (retro-aortic) node. These additional tissues do not participate in the initiation and co-ordination of the heart beat and instead they are likely to be the source of various life-threatening arrhythmias. During embryological development, all parts of the CCS have been shown to develop from the primary myocardium of the linear heart tube, partly under the influence of the transcription factor, Tbx3. [source]

    The guanine nucleotide binding protein , polypeptide 3 gene C825T polymorphism is associated with elite endurance athletes

    EXPERIMENTAL PHYSIOLOGY, Issue 3 2009
    Nir Eynon
    A functional C825T polymorphism in the human guanine nucleotide binding protein , polypeptide 3 (GNB3) gene has been associated with enhanced G protein activation. Since reports regarding the interaction between physical activity and the GNB3 C825T polymorphism are limited and inconsistent, the aim of this study was to determine the frequency of C825T alleles among 155 elite Israeli athletes (endurance athletes and sprinters) and 234 healthy control subjects. Genotyping for GNB3 C825T was performed using polymerase chain reaction on DNA from leucocytes. Results showed that there was a significant difference in GNB3 C825T polymorphism genotype frequencies between endurance athletes and sprinters (P= 0.045) as well as between endurance athletes and control subjects (P= 0.046). We also observed a significantly higher proportion of the GNB3 TT genotype in the group of endurance athletes (19%) compared with the sprinters (5%, P= 0.014) and the control subjects (8.5%, P= 0.026). In the group of athletes, the odds ratio of GNB3 TT genotype being an endurance athlete was 4.49 (95% confidence interval 1.4,14.3) and of GNB3 CC genotype was 0.91 (95% confidence interval 0.47,1.77). These results were even more pronounced when we compared between the subgroups of 20 top-level endurance athletes and 24 top-level sprinters. We conclude that in Israeli athletes the GNB3 TT genotype is higher in elite endurance athletes than it is in sprinters, and within the endurance group it is higher in top-level athletes, suggesting a positive association between the TT genotype and the likelihood of being an elite endurance athlete. [source]

    Functional anatomy and muscle moment arms of the pelvic limb of an elite sprinting athlete: the racing greyhound (Canis familiaris)

    JOURNAL OF ANATOMY, Issue 4 2008
    S. B. Williams
    Abstract We provide quantitative anatomical data on the muscle,tendon architecture and geometry of the pelvic limb of an elite sprint athlete, the racing greyhound. Specifically, muscle masses, muscle lengths, fascicle lengths, pennation angles and muscle moment arms were measured. Maximum isometric force and power of muscles, the maximum muscle torque at joints and tendon stress and strain were estimated. We compare data with that published for a generalized breed of canid, and other cursorial mammals such as the horse and hare. The pelvic limb of the racing greyhound had a relatively large volume of hip extensor muscle, which is likely to be required for power production. Per unit body mass, some pelvic limb muscles were relatively larger than those in less specialized canines, and many hip extensor muscles had longer fascicle lengths. It was estimated that substantial extensor moments could be created about the tarsus and hip of the greyhound allowing high power output and potential for rapid acceleration. The racing greyhound hence possesses substantial specializations for enhanced sprint performance. [source]

    Functional anatomy and muscle moment arms of the thoracic limb of an elite sprinting athlete: the racing greyhound (Canis familiaris)

    JOURNAL OF ANATOMY, Issue 4 2008
    S. B. Williams
    Abstract We provide quantitative muscle,tendon architecture and geometry data for the racing greyhound thoracic limb. Muscle mass, belly length, fascicle lengths, pennation angles and moment arms were measured, as were tendon masses and lengths. Maximum isometric force and maximum power were estimated for muscles, and maximum stress and strain were estimated for tendons. Results are compared with other fast quadrupedal runners, and to previously published data in mixed-breed dogs. The implications of the functional adaptations of the greyhound thoracic limb for sprinting performance are discussed. The thoracic limb was found to benefit from a similar proportion of locomotor muscle mass to the pelvic limb, suggesting that it may be used to some extent in propulsion, or alternatively that stabilisation is very important in this animal. Extrinsic muscles, especially latissimus dorsi and pectoralis profundus, were predicted to be powerful and important for generating net positive work during accelerations. Proximal biarticular muscles show specialisation toward preventing collapse of the shoulder and elbow joints to enable strut-like limb function, or some form of dynamic control. Distal muscles did not appear specialised for elastic energy storage, a functional difference to pelvic limb muscles, and the equivalents in horse thoracic limbs. The greyhound thoracic limb appears to possess substantial differences from both that of more ,sub-maximal specialist' quadrupeds, and from the greyhound pelvic limb. [source]

    Magnanimity, Athletic Excellence, and Performance-Enhancing Drugs

    JOURNAL OF APPLIED PHILOSOPHY, Issue 1 2009
    MICHAEL W. AUSTIN
    abstract In this paper, I first develop a neo-Aristotelian account of the virtue of magnanimity. I then apply this virtue to ethical issues that arise in sport, and argue that the magnanimous athlete will rightly use sport to foster her own moral development. I also address how the magnanimous athlete responds to the moral challenges present in sport by focusing on the issue of performance-enhancing drugs, and conclude that athletic excellence as it is conventionally understood, without moral excellence, has very little value. [source]

    Asthma, allergy, the athlete and the Olympics

    ALLERGY, Issue 4 2008
    K.-H. Carlsen
    First page of article [source]