首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The aim of this study is to examine the cumulative effects of prolonged intensive training with or without rapid weight changes (RWC) on salivary parameters of elite female Taekwondo (TKD) athletes. Ten elite female Taiwanese TKD athletes (ages: 21.3 ± 1.2 years of age, Ht 164.4 ± 5.6 cm) volunteered to participate in this study. Resting saliva samples were collected at 28‐, 14‐, 7‐, and 1 day before and 1‐, 7‐, 21 days after a national competition. The levels of salivary immunoglobulin A (sIgA), cortisol, and lactoferrin were measured. In analyzing the anthropometric data, we found that a significant proportion (50%) of elite female TKD athletes had RWC shortly before and after a national competition. The participants were allocated either to the RWC or to the non‐RWC group according to their weight change profiles. Our results showed that levels of sIgA and cortisol of athletes with RWC were significantly modulated during the study period. However, athletes without RWC only showed reduced lactoferrin after competition. The results presented here demonstrate that intensive training in combination with RWC affects the mucosal immunity and disrupts the cortisol stress response of elite female TKD athletes.  相似文献   

2.
3.
Haematocrit in elite athletes   总被引:2,自引:0,他引:2  
It is possible to increase haemoglobin (Hb) and haematocrit (Ht) to non-physiological values by injecting recombinant human erythropoietin (rhEPO). Although this treatment may result in a better performance of athletes, it may also cause a health risk. To prevent doping with rhEPO, the Union Cycliste Internationale has decided to exclude male cyclists with Ht>0.50 and female cyclists with Ht>0.47 from competition. These cut-off values, however, may result in a non-justified exclusion of clean athletes. To test this hypothesis, we measured the Ht of elite athletes (50 men and 41 women) during a total study period of 43 months. Ht was compared with that in healthy control subjects (134 men and 144 women). No significant differences in Ht were detected between male elite athletes and their references and female elite athletes and their references (P>0.05). In both populations, however, male subjects were found with Ht>0.50, 6 controls and 5 elite athletes (4 highlanders and 1 lowlander). In the female subjects 5 controls but not one of the athletes exceeded a Ht>0.47. "Increased" Ht values among athletes were mainly seen in highlanders. The study shows that it is very difficult to set up a decision value for Ht with regard to doping by erythropoietin.  相似文献   

4.
PURPOSE: Although under normal circumstances exercise prevents thrombosis, there are cases in the literature that indicate a connection between exercise and the onset of thrombosis. In the average population, hereditary thrombophilia is a major cause of thrombosis. However, nothing is known about the prevalence of hereditary thrombophilia in elite athletes. Because high-performance sports are known to carry an increased risk of thrombogenesis, measures to avoid thrombosis must be initiated in cases of known hereditary thrombophilia. METHODS: Hereditary thrombophilia was checked for in 173 elite athletes, members of the German national team. Antithrombin III, protein C, protein S, and the APC ratio, followed by a molecular genetic analysis, were measured, and molecular analysis of factor II G20210A mutation was used to detect the presence of an antithrombin III-, protein C- and protein S-deficiency, as well as factor V Leiden (factor V 506Arg to Gln) and factor II G20210A mutation. RESULTS: No definite antithrombin III-, protein C- or protein S-deficiency was found. In 12 cases, an APC resistance caused by a factor V Leiden mutation (11 heterozygous; 1 homozygous) was detected. In 10 cases, a heterozygous factor II G20210A was observed; a combination of both mutations was not found. For factor V Leiden, this corresponds to a prevalence of 6.9% (CI 95% 3.6-11.8%) in our group, similar to prevalence rates in the general population. Additionally, the observed prevalence of 5.8% (CI 95% 2.8-10.4%) of factor II G20210A is nearly within the range as reported by several authors. CONCLUSION: Based on the observed prevalence of APC resistance and factor II G20210A mutation in our group of athletes, along with consideration of additional circumstantial risks, screening tests for elite athletes should be considered to allow the undertaking of preventive measures.  相似文献   

5.
Several studies in the past few decades have shown that very intense and repeated exercise, particularly when performed over many years, could cause respiratory health problems. The prevalence of exercise-induced asthma has increased in the athletic population, particularly in elite athletes and has not been published in North African athletes. The aim of this study was to determine the prevalence of exercise-induced asthma and/or exercise-induced bronchoconstriction in Tunisian elite athletes. Each participant responded to a questionnaire about respiratory symptoms and medical history and underwent a resting spirometry testing before exercise. Exercise-induced bronchoconstriction was defined as a decrease of at least 15% in pre-exercise forced expiratory volume in one second at any time point after exercise. Post-exercise spirometry revealed the presence of exercise induced bronchoconstriction in 14 out of 107 (13%) elite athletes, while only 1.8% of the subjects reported having previously diagnosed asthma. The prevalence of exercise-induced bronchoconstriction was 19% (8/42) among those athletes training outdoors and 10% (6/65) among those training indoors. In conclusion, our findings indicate that a significant number of Tunisian athletes had exercise-induced bronchoconstriction while not diagnosed before.  相似文献   

6.
The health benefits of leisure-time physical activity are well known, however the effects of engaging in competitive sports on health are uncertain. This literature review examines mortality and longevity of elite athletes and attempts to understand the association between long-term vigorous exercise training and survival rates. Fourteen articles of epidemiological studies were identified and classified by type of sport. Life expectancy, standardised mortality ratio, standardised proportionate mortality ratio, mortality rate, and mortality odds ratio for all causes of death were used to analyse mortality and longevity of elite athletes. It appears that elite endurance (aerobic) athletes and mixed-sports (aerobic and anaerobic) athletes survive longer than the general population, as indicated by lower mortality and higher longevity. Lower cardiovascular disease mortality is likely the primary reason for their better survival rates. On the other hand, there are inconsistent results among studies of power (anaerobic) athletes. When elite athletes engaging in various sports are analysed together, their mortality is lower than that of the general population. In conclusion, long-term vigorous exercise training is associated with increased survival rates of specific groups of athletes.  相似文献   

7.
Despite the passage of time, masters athletes are still capable of incredible performances. Nevertheless, overuse injuries are the most common challenge in this escalating cohort. The incidence of exertion-related cardiovascular events is also greater among older athletes, especially men, highlighting the importance of a thorough preparticipation medical evaluation before entry into senior athletic training programs and competition. Accordingly, masters athletes with a moderate to high risk for coronary artery disease, who desire to enter vigorous competitive events, should undergo peak or symptom-limited exercise testing. Training programs for senior athletes should be individually tailored and focus on the predominant energy pathways and performance requirements for a given sport. Although competition and "personal bests" are important, protection against sickness and disability are increasingly listed as the primary participative motives of older athletes.  相似文献   

8.
Body composition of elite American athletes   总被引:1,自引:0,他引:1  
Five hundred twenty-eight male athletes participating in 26 Olympic events and 298 female athletes participating in 15 Olympic events underwent determination of body fat percentage (% fat) and lean body mass (LBM) via hydrostatic weighing and/or anthropometric methods. All groups of athletes were below the average values for % fat of college age men and women of 15% and 25%, respectively. In general, athletes involved in a sport where their body weight is supported, such as canoe and kayak (males, 13.0 +/- 2.5%; females, 22.2 +/- 4.6%) and swimming (males, 12.4 +/- 3.7%; females 19.5 +/- 2.8%), tended to have higher % fat values. Athletes involved in sports where a weight class has to be made to compete, such as boxing (males, 6.9 +/- 1.6%) and wrestling (male, Junior World Freestyle 7.9 +/- 2.7%), events such as the 100, 200, and 400 meters in athletes (male 100 and 200 meters, 6.5 +/- 1.2%; female 100, 200 and 400 meters, 13.7 +/- 3.6%) that are very anaerobic in nature and extremely aerobic events such as the marathon (males, 6.4 +/- 1.3%) demonstrated lower % fat values. Athletes involved in sports where body size is a definite advantage, such as basketball (males, 84.1 +/- 6.2 kg; females, 55.3 +/- 4.9 kg) and volleyball (males, 75.0 +/- 6.6 kg; females, 58.4 +/- 4.5 kg) tended to have a larger LBM.  相似文献   

9.
ObjectivesIt is not uncommon for athletes to be diagnosed with iron deficiency, yet there remains uncertainty whether the prevalence of suboptimal iron status in elite athletes differs from the normal population or warrants routine screening. The purpose of this study is to describe the distribution of serum ferritin (SF) in a cohort of elite athletes.DesignRetrospective cohort study.MethodsElectronic health records of 1085 elite adult athletes (570 women, 515 men) from 2012–2017 were examined retrospectively. SF values were compared to published normal population data. The proportion of athletes meeting criterion values for iron deficiency or initiation of treatment was examined.ResultsSF distributions in male athletes were significantly lower than normal males aged 20 to <24 yrs. (χ2 28.8, p < 0.001) and aged 24 to <28 yrs. (χ2 91.9, p < 0.001). SF status was similar in female athletes and normal women aged 20 to <24 yrs. (χ2 9.5, p > 0.05) or aged 24 to <28 yrs. (χ2 11.5, p > 0.05). Using 35 ng/ml as the criterion value for stage one iron deficiency, 15% of male athletes and 52% of female athletes displayed suboptimal iron status.ConclusionsMale athletes have a significantly lower population distribution of SF values as compared to normative data on healthy males, with 15% of male athletes having suboptimal SF status. The distribution of SF values in elite female athletes did not differ from population values, however approximately half women athletes were iron deficient. These data suggest that iron screening should be considered in both male and female athlete populations.  相似文献   

10.
To be successful in international competitions, judo athletes must achieve an excellent level of physical fitness and physical condition during training. This article reviews the physiological profiles of elite judo athletes from different sex, age and weight categories. Body fat is generally low for these athletes, except for the heavyweight competitors. In general, elite judo athletes presented higher upper body anaerobic power and capacity than non-elite athletes. Lower body dynamic strength seems to provide a distinction between elite and recreational judo players, but not high-level judo players competing for a spot on national teams. Even maximal isometric strength is not a discriminant variable among judo players. However, more studies focusing on isometric strength endurance are warranted. Although aerobic power and capacity are considered relevant to judo performance, the available data do not present differences among judo athletes from different competitive levels. Typical maximal oxygen uptake values are around 50-55?mL/kg/min for male and 40-45?mL/kg/min for female judo athletes. As for other variables, heavyweight competitors presented lower aerobic power values. The typical differences commonly observed between males and females in the general population are also seen in judo athletes when analysing anaerobic power and capacity, aerobic power, and maximal strength and power. However, further research is needed concerning the differences among the seven weight categories in which judo athletes compete.  相似文献   

11.
Over the past decade, there has been a surge in the number of sports opportunities available to young athletes. Although physicians, parents, and coaches should promote healthy activity and participation, intense training at a young age can predispose exuberant young athletes to certain difficulties. Elite young athletes are at risk for overuse and growth plate injuries in certain sports. Intense training combined with inadequate nutrition may cause growth delay in elite young athletes, but this delay does not appear to affect permanent adult height. Weight training, when done properly, is safe and effective for prepubescent and pubescent athletes. Awareness of neurobehavioral development can help guide the process for appropriate sports participation. Young athletes should be closely monitored for signs of excessive physical and emotional stress so that sports participation can be fun and rewarding.  相似文献   

12.
Physiological characteristics of elite judo athletes   总被引:2,自引:0,他引:2  
In order to provide some understanding of the physiological capacities underlying successful judo performance, representative values for a variety of physiological variables were determined in nationally ranked male (n = 18) and female (n = 9) judo athletes. Body composition, aerobic capacity, isokinetic elbow and knee flexor and extensor strength, and muscle fiber size and composition of the vastus lateralis were examined. Comparisons across weight divisions indicate that the values of many characteristics varied as a function of size. As weight division increased, relative VO2 decreased (r = -0.53 and -0.63 for males and females, respectively), % body fat increased (r = 0.64, 0.72), and the cross sectional areas of Type I (r = 0.55, 0.77) and Type IIA (r = 0.47, = 0.76) muscle fibers increased. Among females in particular, athletes in the higher weight divisions were stronger relative to LBM than those in the lower division. These results indicate that the physiological profiles of lower and upper weight division elite judo players differ markedly. It is suggested that the factors responsible for success may be specific to each weight division and may represent a compromise between making weight and maximizing physiological capacities and performance.  相似文献   

13.
Sport Sciences for Health - Recent studies suggest that professional athletes seem to experience significant sleeping problems. However, little is still known about the occurrence of sleeping...  相似文献   

14.
Koh ES  Lee JC  Healy JC 《Clinical radiology》2007,62(11):1036-1043
Overuse injuries are a common finding in elite athletes. Magnetic resonance imaging (MRI) is the optimal method for the diagnosis of overuse injury in athletes of all levels. We present a review of common and important overuse injuries occurring in elite athletes. A systematic approach based on the functional anatomic units - tendons, bones and joints - may assist in diagnosis of these injuries.  相似文献   

15.
16.
Aim: To examine the ‘lived experiences’ of physiotherapists while treating elite athletes. Participants: Ten practising staff in south-west England, UK. Methods: After giving informed consent, in-depth interviews were conducted and member-checked. Adopting a hermeneutical approach, data reduction was undertaken by individuals, and then rebuilt by the research team in a consensus-building process. Findings: The essence of the lived experience of treating elite athletes was one of ‘working-ness’. In describing experiences of how well rehabilitation was working, physiotherapists expressed a wide range of ‘knowing’ about rehabilitation and about elite athletes. However, the quality of the physiotherapists experience was often a product of local politics, short time frames and interpersonal relationships. Accounts resonated with Merleau-Ponty's concepts of ‘in-the-body’, and Husserl's ‘Being in the world’. Elite athletes were seen in terms of their: (1) 100%-ness, (2) individualized injury experience, (3) ignorant knowing, and of how (4) soccer is different. To describe their own part in the rehabilitation process, physiotherapists spoke about ‘I-who’ and this involved: (5) trying to keep everyone happy, (6) getting into the sport, but staying outside the game, (7) offering ‘real’ and ‘service’ treatments, and (8) Using ‘goaling’ to retrieve athleticism. Physiotherapists were concerned with the ‘working-ness’ of their practices and relationships. They used many ways of ‘knowing’ about their effectiveness to do what they feel is an important, but often stressful, job. These issues provide an important addition to existing templates of professional preparation of, and support for, sports specialists.  相似文献   

17.
The aim of the study was to examine the hypothesis that when former high-level athletes retired from competition, bradycardia would vanish. ECG changes and factors possibly related to the persistence of bradycardia were investigated. We performed a longitudinal follow-up study in 157 former elite athletes who had records of bradycardia < 50 bpm when they were active in high-level competition. All had retired from competitive sport for a minimum of five years prior to participation in the follow-up examination. Data on sport modality, hours of weekly training during competition periods, years participating in high-level competition, and years since retirement from competition were abstracted from medical records at two sports medicine centers. ECGs from this time were studied. At the post-retirement follow-up examination, participants underwent a clinical examination that included blood pressure and ECG recordings, and answered a structured questionnaire about their physical exercise since retirement from their sporting career. In the post-retirement period, a total of 65 % of participants had persistent bradycardia, 18 % with bradycardia < 50 bpm. Multivariate analysis showed that persistence of resting bradycardia was associated with regular exercise and number of years in high-level competition, but not with symptoms such as palpitations, dizziness or syncope, or major ECG alterations.  相似文献   

18.
INTRODUCTION: Eccentric exercise, where the contracting muscle is lengthened, produces microscopic damage in muscle fibers, and sensations of stiffness and soreness, the next day. These normally resolve within a week. A more major sports injury is the muscle strain. Because strain injuries are known to occur during eccentric contractions, it is hypothesized that the microscopic damage from eccentric exercise can, at times, progress to a muscle strain. As the amount of microscopic damage depends on the muscle's optimum length for active tension, it is further proposed that optimum length is a measure of susceptibility for muscle strains. The athletes most at risk of a hamstring strain are those with a previous history of such injuries. Here the prediction is tested that optimum lengths of previously injured hamstrings are shorter and therefore more prone to eccentric damage than uninjured muscles. METHODS: Mean optimum angle for peak torque in a previously injured muscle of nine athletes with a history of unilateral hamstring strains was compared with the uninjured muscle of the other leg and with muscles of 18 uninjured athletes. Optimum angle was determined with isokinetic dynamometry. RESULTS: In previously injured muscles, torque peaked at significantly shorter lengths than for uninjured muscles. Peak torque and quadriceps:hamstrings torque ratios were not significantly different. CONCLUSIONS: The shorter optimum of previously injured muscles makes them more prone to damage from eccentric exercise than uninjured muscles and this may account for the high reinjury rate. The shorter optimum may reflect the muscle's preinjury state or be a consequence of the healing process. To reduce the incidence of strain injuries, it is recommended that a combined program of eccentric exercise and muscle testing be carried out.  相似文献   

19.
This study compared the thickness of the biceps and supraspinatus tendons, the widths of the subacromial space in the frontal and scapular planes, and abnormal sonographic findings in the shoulders of injured, and uninjured elite college baseball athletes and healthy controls. This study recruited two groups of 42 and 12 athletes, with and without histories of shoulder injuries, respectively, as well as one control group of 16 college students who were matched for physical characteristics but not involved in sports. The results showed that the thickness of the biceps and supraspinatus tendons and the subacromial space widths at 0 degrees and 90 degrees shoulder abduction in the frontal plane were significantly greater in the athletes than in the controls (P-values <0.004). The occurrences of the acromioclavicular joint bulging, bicep tendon degeneration, infraspinatus tendon degeneration and infraspinatus cortical irregularity differ significantly between the injured athlete and the group of uninjured athletes and controls (P-values <0.05). However, only infraspinatus tendon degeneration corresponded to the injury histories. There was a high similarity of sonographic spectrum of abnormal findings among the groups. Longitudinal follow-ups are required to determine the clinical importance of the sonographic spectrums and the occurrences of abnormal finding in asymptomatic athletes' shoulders.  相似文献   

20.
To increase our knowledge on the effects of previous and current physical activity on cardiovascular health, we studied a group of Finnish male former elite athletes (endurance, n = 49; power, n = 50) and their 49 age and area‐matched controls, aged 64–89 years. Body mass index (BMI), fasting serum glucose, lipids, blood pressure, and ultrasonography of cardiac and carotid artery structure and function were measured. Former endurance athletes smoked less, had lower prevalence of hypertension, and had higher intensity and volume of leisure time physical activity (LTPA) than the controls. No difference was detected in cardiac or carotid artery structure and function between these groups. Former athletes performing high‐intensity LTPA were slightly younger (possible selection bias), had lower BMI and waist circumference, lower use of antihypertensives, lower prevalence of diabetes, lower pulse wave velocity, and higher carotid artery elasticity than former athletes not performing high‐intensity LTPA. In conclusion, former athletes had a higher intensity and volume of LTPA than the controls. Athletes performing vigorous LTPA had more elastic arteries than athletes performing moderately or no LTPA. Vigorous LTPA through the whole lifetime associates with good cardiovascular health, although the previous medical history may play an important role.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号