808 resultados para ELITE ATHLETES


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High intensity systematic physical training leads to myocardial morphophysiological adaptations. The goal of this study was to investigate if differences in training were correlated with differences in cardiac sympathetic activity.58 males (19-47 years), were divided into three groups: strength group (SG), (20 bodybuilders), endurance group (EG), (20 endurance athletes), and a control group (CG) comprising 18 healthy non-athletes. Cardiac sympathetic innervation was assessed by planar myocardial I-123-metaiodobenzylguanidine scintigraphy using the early and late heart to mediastinal (H/M) ratio, and washout rate (WR).Left ventricular mass index was significantly higher both in SG (P < .001) and EG (P = .001) compared to CG without a statistical significant difference between SG and EG (P = .417). The relative wall thickness was significantly higher in SG compared to CG (P < .001). Both left ventricular ejection fraction and the peak filling rate showed no significant difference between the groups. Resting heart rate was significantly lower in EG compared to CG (P = .006) and SG (P = .002). The late H/M ratio in CG was significantly higher compared to the late H/M for SG (P = .003) and EG (P = .004). However, WR showed no difference between the groups. There was no significant correlation between the parameters of myocardial sympathetic innervation and parameters of left ventricular function.Strength training resulted in a significant increase in cardiac dimensions. Both strength and endurance training seem to cause a reduction in myocardial sympathetic drive. However, myocardial morphological and functional adaptations to training were not correlated with myocardial sympathetic activity.

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Taekwondo practice has been associated with physical and biomechanical overloads, which are related to occurrence of sports injuries (SI). However, etiological and nosographic information about SI are limited and conflicting. This study analyzed and characterized the SI in Taekwondo athletes, according to gender. Casuistic integrated 22 athletes, 12 men and 10 women, athletes from São Paulo State Team of Taekwondo, adult category, with 23,6±6,8 years, body weight of 66,0±13,1 kg and 1,72±0,09 m of height. Reported morbidity survey was used to obtain retroactive information to 2009 season. Nosographic variables were analyzed using Goodman’s Test for contrasts among multinomial populations. All athletes reported injuries in the season; 56 cases were registered, determining an injury rate of 2.54 SI/athlete; 26 events (46.4%) occurred in males (2.17 SI/athlete), and 30 (53.6%) were related to women (3.00 SI/athlete). There were predominance of injuries in joints (35,7%) and muscles (39,3%); both genders presented injuries in lower members (82.1%, p<0.01), predominant in combat situations (80.4%, p<0.05), during the preparatory period of training (73.2%). There was a higher treatment request among male athletes (73.1%), which showed high asymptomatic return (69.2%); the female group referred similar proportions of absence and presence of treatment request, collaborating for the greater symptomatic return of these athletes (70.0%). In conclusion, the results support predominance of muscles and joints injuries in lower segments, derived from fighting, involving female athletes.

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The aim of this article is to analyse the meaning of Mercosur for Brazilian foreign policy. To this end, we discuss the perceptions of the Brazilian elites concerning the regional integration process. The defence of the principle of inter-governmentalism is related to the conception of Mercosur's place within Brazil's international relations. The fact that principles such as universalism and sovereignty are very highly valued ends up affecting the deepening of the integration. The hypothesis of this article is that the Mercosur structure is in line with the perceptions of part of the Brazilian elites, which has put less emphasis on integration since the late 1990s. Our argument is that the current structure is insufficient to guarantee the dynamics of integration.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC

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Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC

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AIM: The purpose of this study was to examine the effect of intensive practice in table-­tennis on perceptual, decision-­making and motor-­systems. Groups of elite (HL=11), intermediate (LL=6) and control (CC=11) performed tasks of different levels. METHODS: All subjects underwent to reaction-­time-­test and response-­time-­test consisting of a pointing task to targets placed at distinct distances (15 and 25-­cm) on the right and left sides. The ball speed test in forehand and backhand condition just for HL and LL group. RESULTS: In CC group reaction time was higher compared to HL (P< 0.05) group. In the response-­time-­test, there was a significant main effect of distance (P< 0.0001) and the tennis-­table expertise (P= 0.011). In the ball speed test the HL were constantly faster compared to the LL in both forehand stroke (P< 0.0001) and backhand stroke (P< 0.0001). Overall, the forehand stroke was significantly faster than the backhand stroke. CONCLUSION: We can conclude that table-­tennis-­players have shorter response-­times than non-­athletes and the tasks of reaction-­time and response-­time are incapable to distinguish the performance of well-­trained table tennis players of the intermediate player, but the ball speed test seems be able to do it.

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Little information is available related to adolescent calcium intake and relationships with injuries they might suffer from sport participation. To determine calcium intake of high school athletes, to assess their self reported injury rates, and to examine the relationship between the two over a 12 month period of time. Participants received a questionnaire at their school and completed it anywhere they found convenient. Adolescent athletes in the Lincoln Public School system (n=43) that participated in at least one sport in the past year. Four age groups participated in the study with sixteen year olds having a significantly higher calcium intake at 1297 mg that of fourteen year olds. A variety of sports were represented with largest number of respondents participating in baseball/or softball at (55%). The next most played sport was basketball at (18%). Median total diet calcium was 1144.5 mg with a mean of 1182 mg + 567 mg. For the frequency of injuries that caused a missed practice or game in the past year, ankle injuries were the most common (25%). Knee injuries were the second most common (17%), followed closely by hand injuries (8%). Mean total diet calcium of athletes with five or more injuries that caused a missed practice or game was significantly higher at 1966 mg (P<.05) than athletes mean diet calcium with zero, one, two, and three injuries. Total milk calcium of those who reported three injuries that resulted in broken or fractured bones or dislocated joints was significantly higher (P<.05) at 1286 mg of total milk calcium than those who reported having zero, one, or two breaks or fractures. Athletes with higher calcium intakes have a higher number of reported injuries. This may be the result of increased vigorous activity which leads to increased calorie and calcium consumption. More importantly, this increased activity leads to an increased chance of injury. The greater calcium intake correlated with greater number of injuries may also be because of third parties advising the athletes who get injured to drink more milk and get more calcium in their diets because they have been injuries already.

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The aim of this study was to compare time-motion indicators during judo matches performed by athletes from different age groups. The following age groups were analysed: Pre-Juvenile (13-14 years, n=522), Juvenile (15-16 years, n 353); Junior (19 years, n = 349) and Senior (>20 years, n = 587). The time-motion indicators included: Total Combat Time, Standing Combat Time, Displacement Without Contact, Gripping Time, Groundwork Combat Time and Pause Time. Analysis of variance (ANOVA) one-way and the Tukey test, as well as the Kruskal-Wallis test and Mann-Whitney (for non-parametric data), were conducted, using P < 0.05 as significance level. The results showed that all analysed groups obtained a median of 7 (first quantile - 3, third quantile - 12) sequences of combat/pause cycles. In total time of combat, the result was: for Total Combat Time, Standing Combat Time and Gripping Time: Pre-Juvenile and Senior were significantly longer than Juvenile and Junior. Considering Displacement Without Contact, Junior was significantly longer than all other age groups. For Groundwork Combat Time, Senior was significantly longer than all other age groups and Pre-Juvenile was longer than Junior. These results can be used to improve the physiological performance in intermittent practices, as well as technicaltactical training during judo sessions.

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The purpose of this study was to investigate energy system contributions and energy costs in combat situations. The sample consisted of 10 male taekwondo athletes (age: 21 +/- 6 years old; height: 176.2 +/- 5.3 cm; body mass: 67.2 +/- 8.9 kg) who compete at the national or international level. To estimate the energy contributions, and total energy cost of the fights, athletes performed a simulated competition consisting of three 2 min rounds with a 1 min recovery between each round. The combats were filmed to quantify the actual time spent fighting in each round. The contribution of the aerobic (WAER), anaerobic alactic (W-PCR), and anaerobic lactic (Wleft perpendicularLA-right perpendicular) energy systems was estimated through the measurement of oxygen consumption during the activity, the fast component of excess post-exercise oxygen consumption, and the change in blood lactate concentration in each round, respectively. The mean ratio of high intensity actions to moments of low intensity (steps and pauses) was similar to 1:7. The W-AER, W-PCR and (Wleft perpendicularLA-right perpendicular) system contributions were estimated as 120 +/- 22 kJ (66 +/- 6%), 54 +/- 21 kJ (30 +/- 6%), 8.5 kJ (4 +/- 2%), respectively. Thus, training sessions should be directed mainly to the improvement of the anaerobic alactic system (responsible by the highintensity actions), and of the aerobic system (responsible by the recovery process between high- intensity actions).

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The purpose of this study was to determine the physiological, anthropometric, performance, and nutritional characteristics of the Brazil Canoe Polo National Team. Ten male canoe polo athletes (age 26.7 +/- 4.1 years) performed a battery of tests including assessments of anthropometric parameters, upper-body anaerobic power (Wingate), muscular strength, aerobic power, and nutritional profile. In addition, we characterized heart rate and plasma lactate responses and the temporal pattern of the effort/recovery during a simulated canoe polo match. The main results are as follows: body fat, 12.3 +/- 4.0%; upper-body peak and mean power, 6.8 +/- 0.5 and 4.7 +/- 0.4 W . kg(-1), respectively; 1-RM bench press, 99.1 +/- 11.7 kg; peak oxygen uptake, 44.3 +/- 5.8 mL . kg(-1) . min(-1); total energy intake, 42.8 +/- 8.6 kcal . kg(-1); protein, carbohydrate, and fat intakes, 1.9 +/- 0.1, 5.0 +/- 1.5, and 1.7 +/- 0.4 g . kg(-1), respectively; mean heart rate, 146 +/- 11 beats . min(-1); plasma lactate, 5.7 +/- 3.8 mmol . L-1 at half-time and 4.6 +/- 2.2 mmol . L-1 at the end of the match; effort time (relative to total match time), 93.1 +/- 3.0%; number of sprints, 9.6 +/- 4.4. The results of this study will assist coaches, trainers, and nutritionists in developing more adequate training programmes and dietary interventions for canoe polo athletes.

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The aim of this study was to evaluate the effect of carbohydrate supplementation on free plasma DNA and conventional markers of training and tissue damage in long-distance runners undergoing an overload training program. Twenty-four male runners were randomly assigned to two groups (CHO group and control group). The participants were submitted to an overload training program (days 1-8), followed by a high-intensity intermittent running protocol (10 x 800 m) on day 9. The runners received maltodextrin solution (CHO group) or zero energy placebo solution as the control equivalent before, during, and after this protocol. After 8 days of intensive training, baseline LDH levels remained constant in the CHO group (before: 449.1 +/- 18.2, after: 474.3 +/- 22.8 U/L) and increased in the control group (from 413.5 +/- 23.0 to 501.8 +/- 24.1 U/L, p < 0.05). On day 9, LDH concentrations were lower in the CHO group (509.2 +/- 23.1 U/L) than in the control group (643.3 +/- 32.9 U/L, p < 0.01) post-intermittent running. Carbohydrate ingestion attenuated the increase of free plasma DNA post-intermittent running (48,240.3 +/- 5,431.8 alleles/mL) when compared to the control group (73,751.8 +/- 11,546.6 alleles/mL, p < 0.01). Leukocyte counts were lower in the CHO group than in the control group post-intermittent running (9.1 +/- 0.1 vs. 12.2 +/- 0.7 cells/mu L; p < 0.01) and at 80 min of recovery (10.6 +/- 0.1 vs. 13.9 +/- 1.1 cells/mu L; p < 0.01). Cortisol levels were positively correlated with free plasma DNA, leukocytes, and LDH (all r > 0.4 and p < 0.001). The results showed that ingestion of a carbohydrate beverage resulted in less DNA damage and attenuated the acute post-exercise inflammation response, providing better recovery during intense training.