A fadiga muscular é um fenômeno extensivamente estudado, especialmente por sua influência sobre o desempenho físico. Diversos estudos têm demonstrado que a acidose muscular, ocasionada pelo acúmulo de íons H+ no interior da célula muscular, é um fator limitante para o desempenho físico durante exercícios físicos de alta intensidade. Assim, estratégias com o objetivo de atenuar a queda do pH intramuscular têm o potêncial de se destacar como agente tamponante. Dentre elas, a suplementação de bicarbonato de sódio tem mostrado ser uma interessante estratégia nutricional para o aumento do desempenho anaeróbio. Recentemente a suplementação de lactato tem se mostrado como um possível agente tamponante. Teoricamente a suplementação de lactato pode aumentar os níveis sanguíneos de pH e bicarbonato, assim aumentando a capacidade tamponante extracelular. Os poucos estudos sugerem um potêncial ergogênico desta estratégia nutricional, embora a falta de estudos sugere a necessidade de mais estudos que atestem a eficácia ergogênica deste suplemento. Portanto, esse estudo tem por objetivo investigar o efeito da suplementação crônica de lactato de cálcio sobre os níveis sanguíneos de pH e bicarbonato e desempenho intermitente de alta intensidade; e ainda, compará-los com a suplementação de bicarbonato de sódio. Foram recrutados 18 atletas (idade 26 ± 5 anos; massa corporal 88,8 ± 6,8 kg; estatura 1,78 ± 0,7m; gordura corporal 18,6 ± 6,2 %). A pesquisa teve um desenho randomizado, controlado por placebo, duplo-cego cross-over. Os sujeitos foram alocados em 3 tratamentos diferentes: placebo, lactato de cálcio e bicarbonato de sódio. Todos os tratamentos suplementaram a dose de 500 mg.kg-1, divididas em 4 doses diárias, por um período de cinco dias consecutivos, seguido por dois dias de washout. Os indivíduos foram submetidos a testes de desempenho físico anaeróbio para membros superiores. Foram realizadas 4 séries do teste de Wingate, com duração de 30 segundos em cada série, e carga fixa em 4% do peso corporal, separadas por períodos de recuperação ativa de 3 minutos. As variáveis de potência média, pico e trabalho total, foram usados para verificação de alterações no desempenho em virtude dos tratamentos. Foi ainda avaliado os níveis sanguíneos de pH, bicarbonato e lactato no repouso, após o esforço e 5min após o esforço. A análise de reprodutibilidade do teste de Wingate mostrou que não houve diferenças entre as duas familiarizações e o teste pré-suplementação. As variáveis sanguíneas não foram diferentes entre os testes, e evidenciaram o potêncial do teste em diminuir pH, bicarbonato e excesso ácido-base e aumentar o lactato plasmático. Os resultados mostram que a suplementação de lactato de cálcio não foi capaz de melhorar o desempenho ou influenciar variáveis sanguíneas de bicarbonato e pH, no entanto a suplementação de bicarbonato de sódio melhorou o desempenho em ~2,9% e aumentou os níveis basais de bicarbonato sanguíneo, mas não alterou o pH. Dessa forma conclui-se que tal estratégia não é capaz de aumentar a capacidade tamponante, tampouco de promover melhoras no desempenho intermitente de alta intensidade / Muscle fatigue is an extensively studied phenomenon, especially due to its relevance to performance. Several studies have shown that muscle acidosis caused by hydrogen ion (H+) accumulation in the muscle cell is a limiting factor to physical performance during high-intensity exercise. Thus, strategies aimed at attenuating the fall in intramuscular pH during exercise have the potential to improve performance. Among these strategies, sodium bicarbonate supplementation has been shown to be an effective nutritional strategy for increasing anaerobic performance. Recently, lactate supplementation has been suggested to be an equally effective buffering aid. Theoretically, lactate supplementation can increase blood pH and bicarbonate levels, thereby increasing extracellular buffering capacity. The few studies available to date have shown the ergogenic potential of this nutritional strategy, although the lack of studies with chronic supplementation in addition to the lack of reliable physical tests suggests the need for more studies to confirm the efficacy of lactate supplementation. Therefore, this study aimed to investigate the effect of chronic calcium lactate and sodium bicarbonate supplementation on blood pH, bicarbonate and high-intensity intermittent exercise performance. Eighteen athletes (age 26±5 years; body mass 88,8±6,8 kg; height 1,78± 0,7m; body fat 18,6±6,2 %) were recruited to this randomised, double-blind, placebo-controlled, crossover and counterbalanced study. The participants\' underwent 3 different treatments: placebo, calcium lactate and sodium bicarbonate. The dose in all conditions was 500 mg·kg-1, divided into 4 daily doses, for 5 consecutive days, followed by a 2-day washout period. On the fifth day of supplementation, individuals underwent 4 bouts of the Wingate upper-body anaerobic test. The bouts lasted 30 seconds, with a fixed load of 4% body mass and were separated by active recovery periods of 3 minutes. Mean and peak power, as well as total work done, were recorded during each bout. In addition, blood pH, bicarbonate and lactate were determined at rest, immediately after exercise and 5 min after exercise. The Wingate test reproducibility analysis showed no differences between both familiarisations and a pre-supplementation test while blood variables were not different between tests. Post-exercise values highlighted the potential of the test to decrease blood pH, bicarbonate and base excess and to increase plasma lactate. Results showed that calcium lactate supplementation did not improve upper-body Wingate performance, likely due to a lack of change in blood bicarbonate and pH prior to exercise. Sodium bicarbonate supplementation improved performance by ~2.9% following increased pre-exercise levels of blood bicarbonate but not pH. It can be concluded that calcium lactate supplementation is not capable of increasing buffering capacity, and thus does not promote improvements in high-intensity intermittent performance

L’objectif de ce travail de thèse est d’étudier les effets de l’avance en âge (seulement deux décennies, 20-40 ans) et d’un programme d’entraînement combiné (Sprint et Musculation) sur les performances et les réponses métaboliques et hormonales à l’exercice supramaximal (Wingate-test). Quatre groupes de sujets ont participé à ce travail. Ils ont été répartis selon l’âge en 2 groupes expérimentaux (âgés de 20 et 40 ans) et en groupes contrôles (âgés de 20 et 40 ans). Les résultats montrent que l’entraînement anaérobie de type sprint et musculation s’accompagne d’une augmentation significative du volume plasmatique chez le sujet entrainé (jeune et âgé). Ces changements du volume plasmatique ont été accompagnés par une augmentation des performances physiques et de la lactatémie pic mesurée à la fin de l’exercice Wingate chez les groupes entrainés. Des adaptations endocriniennes sont probablement à l’origine de ces modifications liées à l’entrainement intense. En effet, après entrainement, nous avons observé une augmentation significative des catécholamines (au repos et à l’exercice) chez les sujets âgés entrainés par rapport aux plus jeunes entrainés. La différence liée à l’âge entre jeune et âgée disparait après entrainement seulement entre les groupes entrainés. Le même constat a été observé concernant les concentrations plasmatiques de glucose et d’insuline chez les groupes entrainés après entrainement. Ces changements du métabolisme de glucose sont accompagnés d’une augmentation de la production du cortisol, de la testostérone et de son hormone porteuse chez le groupe âgé entrainé en particulier. La sécrétion de l’hormone de croissance (GH) a augmenté également en dépit de la différence d’âge après entrainement accompagnée de l'augmentation des taux d'IGF1 et d’IGFB3 chez le groupe âgé entrainé en particulier. En conclusion de ce travail de thèse, il semble qu’un entraînement adéquat de sprint et de musculation serait un bon moyen pour réduire et atténuer les effets délétères de l’avance en âge sur la performance anaérobie, les réponses métaboliques et les sécrétions hormonales. / The aim of this thesis is to study the effects of advancing age (only two decades, 20-40 years) and a combined training program (Sprint and Strength) on performance, metabolic and hormonal responses to supramaximal exercise (Wingate-test). Four groups participated in this research. They were divided according to age in to two experimental groups (20 and 40 years of age) and two control groups (20 to 40 years of age). The results show that anaerobic sprint and strength training was accompanied by a significant increase in plasma volume in trained groups (young and elderly). These changes in plasma volume were accompanied by an increase in physical performance and peak lactate measured at the end of the Wingate-test in trained subjects (young and elderly). Endocrine adaptations are probably the origin of these changes related to the intense training. In fact, after training, we observed a significant increase in catecholamines responses at rest and to exercise in trained elderly subjects compared to younger ones. The age-related difference between younger and older disappears after training only between trained groups. The same result was observed in plasma glucose and insulin concentrations in trained groups after training. These changes in glucose metabolism are associated with an increase of cortisol production, testosterone and its precursor steroids only in trained elderly subjects. The secretion of growth hormone (GH) has also increased despite the age difference after training accompanied by an increase of IGF1 and IGFB3 levels only in the trained elderly subjects. In conclusion of this thesis, it seems that an appropriate sprint and strength training would be a good way to attenuate the deleterious effects of advancing age on anaerobic performance, metabolic responses and hormonal secretions.

Title: The effectiveness of conditioning program in the pre-season time in players of the KLH Chomutov ice hockey team. Objectives: The main aim of this study is to determine the effectiveness of conditioning program before the season, using the Wingate Test. Another objective was to determine the load capacity in terms of the on-ice and off-ice training program. We also tried to compare the test results of younger and older players. Methods: During the actual implementation of the thesis, we used selected diagnostic instruments that characterize the level of velocity - power assumptions of ice hockey players in the men's cathegory. For testing we used the Wingate Test. The tests were applied before and at the end of the pre-season time. During the reporting period, we evaluated changes in the level of individual indicators of the Wingate Test. Results: The results show that the off-ice and on-ice conditioning programs do not have the same volume and content of the load. Increased volume and content of the load was observed in the on-ice conditioning program. The content of off-ice conditioning program in the pre-season time in ice hockey is a non-specific activity focused mainly on development of speed-strength abilities. The on-ice training program increases the proportion of the development of...

L'objectif de la présente étude était double : (i) étudier le lien entre la force, la puissance musculaire des membres inférieurs et l'aptitude à répéter des sprints linéaire ou quadrangulaire chez les footballeurs U17 (ii) confronter les astreintes cardiovasculaires et bioénergétiques imposées par ces deux types de sprints. Dix-sept (n=17) footballeurs d'élite Canadien U17 ont effectué dans un ordre randomisé deux types de sprints répétés, linéaires ou quadrangulaires (40 m linéaire ou sur un carré de 4x10 m) étant séparés l'un de l'autre de 48 heures. Les deux types d'exercices ont consisté en la répétition de 6 sprints (6 x 40-m/20-sec) linéaire (RSL) ou quadrangulaire (RSQA). La puissance anaérobie des membres inférieurs était mesurée avec le test de Wingate (30-sec) quant à la force et la puissance explosive étaient évaluées à l'aide d'un accéléromètre (Myotest) au cours d'un test de détente verticale (DV) de type Squat Jump (90°). La fréquence cardiaque (FC) était enregistrée par télémétrie battement à battement en mode R-R et la concentration du lactate plasmatique ([La-]) était dosée 2 minutes après chaque type de sprint ainsi que le test de Wingate. Ces mesures étaient complétées par une mesure de la perception de l'effort sur l'échelle de Borg (RPE). Trois indices de performance ont été calculés pour les exercices de sprints répétés (RSL et RSQA), le meilleur sprint sur 40 m, la moyenne des 6 sprints et l'indice de décrément (ID). On a noté une forte corrélation entre le meilleur sprint linéaire (40 m) avec la force et la puissance musculaire (moyenne et le pic) développées au test de DV (r2=0.56 et 0.46, p<0.0, respectivement). La corrélation de la moyenne des temps en RSL (6 x 40 m) avec le pic de puissance et l'indice de fatigue (IF) mesurée avec le test de Wingate était statistiquement faible (r2=0.29 et 0.31, p<0.05 respectivement). Par ailleurs, aucune corrélation n'a été retrouvée entre les indices de l'aptitude à répéter des sprints linéaire et quadrangulaire. Les réponses physiologiques (FC [La-] et le RPE) étaient nettement plus élevées (p<0.001) lors de la RSQA comparée à la RSL. La force et la puissance (pic et moyenne) musculaire mesurées avec le Myotest sont de meilleurs prédicteurs de l'aptitude à répéter des sprints linéaires que les performances (puissance et IF) dérivées du test de Wingate. Par ailleurs, la sollicitation cardiaque et bioénergétique est plus importante lors de la RSQA comparée à la RSL. Décidément, nous concluons que l'aptitude à répéter des sprints linéaires et celle à répéter des sprints quadrangulaires sont deux habiletés motrices de registre physiologique différent qui doivent être entraînées et évaluées séparément. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Football, physiologie, test de Wingate, Myotest, sprints répétés.

Thesis (M.S.)--Georgia Southern University, 2007. / "A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Under the direction of Jim McMillan. ETD. Electronic version approved: May 2007. Includes bibliographical references (p. 32-33) and appendices.

Orientador: Claudio Alexandre Gobatto / Banca: Sergio Augusto Cunha / Banca: Pedro Balikian Junior / Resumo: Dentro do âmbito do treinamento competitivo evidencia-se a necessidade de criar e aperfeiçoar testes que possam ser aplicados no próprio ambiente de treinamento, priorizando a busca da especificidade na avaliação e de variáveis que possam melhor explicar as alterações do desempenho do atleta. Então, surge uma problemática ao avaliar a aptidão anaeróbia em velocistas em função das metodologias e dos protocolos propiciarem difícil aplicação e inespecificidade, principalmente por não possuírem nenhum teste com o movimento específico para esse grupo. Entretanto, destaca-se na literatura alguns testes laboratoriais utilizados para avaliação da aptidão anaeróbia de corredores, dentre os quais estão o Máximo Déficit de Oxigênio Acumulado (MAOD), o teste de Wingate (TW) e os testes de salto vertical (SV). Com isso, o objetivo do estudo foi padronizar o teste de corrida atada (TCA) analisando a validade, reprodutibilidade e confiabilidade. O protótipo criado para o TCA proporciona a obtenção de valores de força e de velocidade durante o teste que, por sua vez, fornecerá parâmetros de potência pico do TCA (PPTCA), potência média do TCA (PMTCA) e do índice de fadiga do TCA (IFTCA). Para tanto, 10 velocistas do sexo masculino (22,0 l 2,8 anos; 68,1 l 8,9 kg; 1,76 l 0,09 m; 8,1 l 3,1 % Gordura) participaram do estudo. Todos os participantes foram submetidos a avaliação antropométrica, teste incremental para determinação do consumo máximo de oxigênio (VO2max) e do limiar anaeróbio (LAn), teste para determinação do MAOD, TW, dois TCA (teste e re-teste) e um esforço máximo na distância de 300 metros (D300m). Através de coletas sangüíneas retirada do lóbulo da orelha após os testes de TW, TCA e D300m, foram determinadas as concentrações pico de lactato sangüíneo ([Lac]p) para cada um dos testes, respectivamente... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the competitive training area, it is observed the necessity to create and improve tests that could be applied in its own training environment, prioritizing the search of the specificity in the evaluation and the variables that can explain the changes of the athlete’s performance better. So, we find a problem concerning the anaerobic fitness evaluation in sprinters due to the methodologies and the protocols, mainly because there are no tests with the specific movement for this particular group. However, it is possible to mention some laboratorial tests that are used to verify the anaerobic fitness performance of the runners, which are, the maximal deficit oxygen accumulated (MAOD), the Wingate test (TW) and the tests of vertical jump (VJ). Thereby, the aim of this study is to standardize the tied running test (TRT), analyzing the validity, reproducibility and reliability. The TRT prototype provides the instantaneous strength and speed values during the test that give peak power (PPTRT), mean power (PMTRT) and fatigue index (FITRT) parameters. Therefore, ten male runners (22.0l2.8 years old, 68.1l8.9 kg, 1.76l0.09 m; 8.1l3.1 % Fat) participated in this study. All the subjects were submitted into the anthropometric assessment, incremental test to determination the maximal consume of oxygen (VO2max) and anaerobic threshold (AT), the MAOD determination test, the TW, the two TRT (test and re-test) and maximum effort in 300 meters of distance (D300m). Through blood samples removed from the earlobe after the TW, TRT and D300m tests, the blood peak lactate concentration ([Lac]peak) was determined in each test, respectively, [Lac]peakTW, [Lac]peakTRT and [Lac]peakD300m. The tests were separated with intervals of 24 to 72 hours. The data were presented in mean and stand deviation (M l SD)...(Complete abstract click electronic access below) / Mestre

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Title: Performance aspects in white water slalom Aim The study is a summary of articles published between the years 2006 - 2011. The aim is to present the researched issue of top - level sport in the example of white water slalom. Articles are arranged in accordance to the factors of sport performance. The first thematically include articles concerned with conditioning factors of performance, then continue articles analyzing somatic factors and at the end there are listed papers on psychological preparation and psychological factors. Methods These articles were mostly case studies which have been conducted on a sample of national team athletes or top athletes in the Czech Republic. The exception is the articles 5.3 and 5.4, which are descriptive studies on a large sample of top world class athletes. The studies used a survey and testing. Results The individual articles addressed the importance of performance indicators in white water slalom, applied to the selected factors. Results of studies are always subjected to deliberately selected files of athletes, top-level competitors in the Czech Republic and abroad. The results, therefore, cannot be generalized and applied to a population of white water slalom racers, but can show some patterns that could be accepted in practice.

Title: Performance aspects in white water slalom Aim The study is a summary of articles published between the years 2006 - 2011. The aim is to present the researched issue of top - level sport in the example of white water slalom. Articles are arranged in accordance to the factors of sport performance. The first thematically include articles concerned with conditioning factors of performance, then continue articles analyzing somatic factors and at the end there are listed papers on psychological preparation and psychological factors. Methods These articles were mostly case studies which have been conducted on a sample of national team athletes or top athletes in the Czech Republic. The exception is the articles 5.3 and 5.4, which are descriptive studies on a large sample of top world class athletes. The studies used a survey and testing. Results The individual articles addressed the importance of performance indicators in white water slalom, applied to the selected factors. Results of studies are always subjected to deliberately selected files of athletes, top-level competitors in the Czech Republic and abroad. The results, therefore, cannot be generalized and applied to a population of white water slalom racers, but can show some patterns that could be accepted in practice.

Bakgrund: Syftet med denna studie var att undersöka effekten av sju dagars tillskott av betain (2,5 gram/dag) på prestationsförmågan i idrottsspecifika tester för manliga vältränade cykelatleter. Metod: Sex (n=6) manliga testpersoner (genomsnitt ± standardavvikelse ålder, 31,7 ± 10,2 år; längd, 188,2 ± 3,6 cm; kroppsvikt; 82,5 ± 7,6 kg; fettfri massa, 71,6 ± 7,3 kg) genomförde förtester bestående av fem counter movement jumps, fyra stycken 12 s wingate-sprinter med 2,5 minuters aktiv vila följt av fem ytterligare counter movement jumps. De blev sedan indelade slumpmässigt i betain- eller placebogrupper. Första testet etablerade basvärden och eftertest ”1” samt ”2” föregicks med antingen sju dagars tillskott med placebo (2,5 g maltodextrin plus 12,5 mg riboflavin) eller betain (2,5 g trimetylglycin plus 12,5 mg riboflavin). Riboflavin användes för att undanröja den fiskliknande doften som kan uppstå vid tillskott av betain. Doseringen bestod av fyra kapslar per dag till måltid, varav två kapslar intogs på morgonen eller förmiddagen (före träning) och två kapslar intogs på eftermiddagen eller kvällen (efter träning). Vi använde oss av en dubbelblindad, kontrollerad randomisering cross-over design; med en veckas washout mellan placebo och betain. Maximum Peak Power, Average Peak Power, Maximum Average Power, Mean Average Power, Mean Relative Power Drop, Maximum Relative Power Drop, CMJ-Medel och CMJ-Max före och efter sprinterna analyserades med two-tailed t-test 2 och 3 för att jämföra skillnader före och efter intag av tillskott samt skillnaderna mellan grupperna.Resultat: Inga signifikanta skillnader kunde noteras. Konklusion: En veckas tillskott av betain gav inte någon signifikant förbättring jämfört med placebo i hopp- och sprintförmåga samt förmåga att ta ut sig själv maximalt hos aktiva cyklister. Fler studier med framförallt större testgrupper efterlyses för att utvärdera betainets ergogena effekt bland aktiva atleter. / The effect of betaine supplementation on counter movement jumps and sprint performance among male bicycle athletes Background: The purpose of this study was to investigate the effect of a seven days supplementation regimen with betaine (2,5 grams per day) on counter movement jumps and sprint performance in trained male bicyclists. Method: Six (n=6) male subjects (mean ± standard deviation age, 31,7 ± 10,2 years; height, 188,2 ± 3,6 cm; bodyweight, 82,5 ± 7,6 kg; lean body mass, 71,6 ± 7,6 kg) completed a 21 day study involving five counter movement jumps (no arm swing) followed by 4 consecutive modified 12 second Wingate sprints on a bicycle ergometer with active rest (2,5 minutes) followed by another set of five counter movement jumps. A double blind, controlled randomized cross over design was used and there was a 1 week washout between the supplementation startup for each group. Following pre-testing (baseline) the participants were randomly divided into groups by choosing one of the following supplements: “12” Placebo –2,5 grams of maltodextrine plus 12,5 mg riboflavin or “11” – Active 2,5 grams of trimethylglycine plus 12,5 mg riboflavin. Riboflavin was used so mask the “fishy odor syndrome” effect of high intakes of trimethylglycine that may cause trimethyluria. Daily consumption of capsules was divided into two doses of two capsules each with meals. One dose (two capsules) was consumed in the morning and one dose in the evening. The following variables were analyzed: Maximum Peak Power, Average Peak Power, Maximum Mean Power, Average Mean Power, Maximum Relative Power Drop, Average Relative Power Drop, Mean CMJ-Pre + Post sprints and Maximal CMJ-Pre + Post sprints. Results: None of the parameters showed statistical significance. Conclusion: Our study indicates that seven days of betaine ingestion does not seem significantly improve counter movement jump or sprint capacity in male trained bicyclists. Larger studies are needed to investigate the performance enhancing effects of betaine, especially among high performance athletes.