Jogos desportivos coletivos e os estimulos das inteligencias multiplas : bases para uma proposta em pedagogia do esporte

Universidade Estadual de Campinas. Faculdade de Educação Física

Mn-doped cubic BN as an atomiclike memory device: A density functional study

We investigate the electronic properties of Mn(B) substitutional doping in cubic boron nitride (BN), for different charge states, using density functional theory (DFT) calculations. We show that the neutral Mn has a nonmagnetic ground state (S=0). Upon charge injection, it is unambiguously shown that the Mn(B)(-) has a high-spin configuration with a strong, localized magnetic moment of 5 mu(Bohr). We developed a simple model, parameterized by the DFT results, that allows us to interpret the rules played by the crystal-field and exchange-correlation splitting in the magnetization process.

Expression of genes related to muscle plasticity after strength and power training regimens

The purpose of our study was to compare the effects of 8-week progressive strength and power training regimens on strength gains and muscle plasticity [muscle fiber hypertrophy and phenotype shift, mammalian target of rapamycin (mTOR), regulatory-associated protein of mTOR (RAPTOR), rapamycin-insensitive companion of m-TOR (RICTOR), calcineurin and calcipressin gene expression]. Twenty-nine physically active subjects were divided into three groups: strength training (ST), power training (PT) and control (C). Squat 1 RM and muscle biopsies were obtained before and after the training period. Strength increased similarly for both ST and PT groups (P < 0.001). Fiber types I, IIa and IIb presented hypertrophy main time effect (P < 0.05). Only type IIb percentage decreased from pre- to post-test (main time effect, P < 0.05). mTOR and RICTOR mRNA expression increased similarly from pre- to post-test (P < 0.01). RAPTOR increased after training for both groups (P < 0.0001), but to a greater extent in the ST (P < 0.001) than in the PT group. 4EBP-1 decreased after training when the ST and PT groups were pooled (P < 0.05). Calcineurin levels did not change after training, while calcipressin increased similarly from pre- to post-test (P < 0.01). In conclusion, our data indicate that these training regimens produce similar performance improvements; however, there was a trend toward greater hypertrophy-related gene expression and muscle fiber hypertrophy in the ST group.

Anabolic steroid associated to physical training induces deleterious cardiac effects

DO CARMO, E. C., T. FERNANDES, D. KOIKE, N. D. DA SILVA JR., K. C. MATTOS, K. T. ROSA, D. BARRETTI, S. F. S. MELO, R. B. WICHI, M. C. C. IRIGOYEN, and E. M. DE OLIVEIRA. Anabolic Steroid Associated to Physical Training Induces Deleterious Cardiac Effects. Med. Sci. Sports Exerc., Vol. 43, No. 10, pp. 1836-1848, 2011. Purpose: Cardiac aldosterone might be involved in the deleterious effects of nandrolone decanoate (ND) on the heart. Therefore, we investigated the involvement of cardiac aldosterone, by the pharmacological block of AT1 or mineralocorticoid receptors, on cardiac hypertrophy and fibrosis. Methods: Male Wistar rats were randomized into eight groups (n = 14 per group): Control (C), nandrolone decanoate (ND), trained (T), trained ND (TND), ND + losartan (ND + L), trained ND + losartan (TND + L), ND + spironolactone (ND + S), and trained ND + spironolactone (TND + S). ND (10 mg.kg(-1).wk(-1)) was administered during 10 wk of swimming training (five times per week). Losartan (20 mg.kg(-1).d(-1)) and spironolactone (10 mg.kg(-1).d(-1)) were administered in drinking water. Results: Cardiac hypertrophy was increased 10% by using ND and 17% by ND plus training (P < 0.05). In both groups, there was an increase in the collagen volumetric fraction (CVF) and cardiac collagen type III expression (P < 0.05). The ND treatment increased left ventricle-angiotensin-converting enzyme I activity, AT1 receptor expression, aldosterone synthase (CYP11B2), and 11-beta hydroxysteroid dehydrogenase 2 (11 beta-HSD2) gene expression and inflammatory markers, TGF beta and osteopontin. Both losartan and spironolactone inhibited the increase of CVF and collagen type III. In addition, both treatments inhibited the increase in left ventricle-angiotensin-converting enzyme I activity, CYP11B2, 11 beta-HSD2, TGF beta, and osteopontin induced by the ND treatment. Conclusions: We believe this is the first study to show the effects of ND on cardiac aldosterone. Our results suggest that these effects may be associated to TGF beta and osteopontin. Thus, we conclude that the cardiac aldosterone has an important role on the deleterious effects on the heart induced by ND.

Role of beta-alanine supplementation on muscle carnosine and exercise performance

ARTIOLI, G. G., B. GUALANO, A. SMITH, J. STOUT, and A. H. LANCHA, JR. Role of beta-Alanine Supplementation on Muscle Carnosine and Exercise Performance. Med. Sci. Sports Exerc., Vol. 42, No. 6, pp. 1162-1173, 2010. In this narrative review, we present and discuss the current knowledge available on carnosine and beta-alanine metabolism as well as the effects of beta-alanine supplementation on exercise performance. Intramuscular acidosis has been attributed to be one of the main causes of fatigue during intense exercise. Carnosine has been shown to play a significant role in muscle pH regulation. Carnosine is synthesized in skeletal muscle from the amino acids L-histidine and beta-alanine. The rate-limiting factor of carnosine synthesis is beta-alanine availability. Supplementation with beta-alanine has been shown to increase muscle carnosine content and therefore total muscle buffer capacity, with the potential to elicit improvements in physical performance during high-intensity exercise. Studies on beta-alanine supplementation and exercise performance have demonstrated improvements in performance during multiple bouts of high-intensity exercise and in single bouts of exercise lasting more than 60 s. Similarly, beta-alanine supplementation has been shown to delay the onset of neuromuscular fatigue. Although beta-alanine does not improve maximal strength or (V) over dotO(2max), some aspects of endurance performance, such as anaerobic threshold and time to exhaustion, can be enhanced. Symptoms of paresthesia may be observed if a single dose higher than 800 mg is ingested. The symptoms, however, are transient and related to the increase in plasma concentration. They can be prevented by using controlled release capsules and smaller dosing strategies. No important side effect was related to the use of this amino acid so far. In conclusion, beta-alanine supplementation seems to be a safe nutritional strategy capable of improving high-intensity anaerobic performance.

Prevalence, magnitude, and methods of rapid weight loss among judo competitors

ARTIOLI, G. G., B. GUALANO, E. FRANCHINI, F. B. SCAGLIUSI, M. TAKESIAN, M. FUCHS, and A. H. LANCHA. Prevalence, Magnitude, and Methods of Rapid Weight Loss among Judo Competitors. Med. Sci. Sports Exerc., Vol. 42, No. 3, pp. 436-442, 2010. Purpose: To identify the prevalence, magnitude, and methods of rapid weight loss among judo competitors. Methods: Athletes (607 males and 215 females; age = 19.3 +/- 5.3 yr, weight = 70 +/- 7.5 kg, height = 170.6 +/- 9.8 cm) completed a previously validated questionnaire developed to evaluate rapid weight loss in judo athletes, which provides a score. The higher the score obtained, the more aggressive the weight loss behaviors. Data were analyzed using descriptive statistics and frequency analyses. Mean scores obtained in the questionnaire were used to compare specific groups of athletes using, when appropriate, Mann-Whitney U-test or general linear model one-way ANOVA followed by Tamhane post hoc test. Results: Eighty-six percent of athletes reported that have already lost weight to compete. When heavyweights are excluded, this percentage rises to 89%. Most athletes reported reductions of up to 5% of body weight (mean +/- SD: 2.5 +/- 2.3%). The most weight ever lost was 2%-5%, whereas a great part of athletes reported reductions of 5%-10% (mean +/- SD: 6 +/- 4%). The number of reductions underwent in a season was 3 +/- 5. The reductions usually occurred within 7 +/- 7 d. Athletes began cutting weight at 12.6 +/- 6.1 yr. No significant differences were found in the score obtained by male versus female athletes as well as by athletes from different weight classes. Elite athletes scored significantly higher in the questionnaire than nonelite. Athletes who began cutting weight earlier also scored higher than those who began later. Conclusions: Rapid weight loss is highly prevalent in judo competitors. The level of aggressiveness in weight management behaviors seems to not be influenced by the gender or by the weight class, but it seems to be influenced by competitive level and by the age at which athletes began cutting weight.

Endothelial nitric oxide synthase polymorphisms and adaptation of parasympathetic modulation to exercise training

SILVA, B. M., F. J. NEVES, M. V. NEGRÃO, C. R. ALVES, R. G. DIAS, G. B. ALVES, A. C. PEREIRA, M. Urbana A. RONDON, J. E. KRIEGER, C. E. NEGRÃO, and A. C. DA NOBREGA. Endothelial Nitric Oxide Synthase Polymorphisms and Adaptation of Parasympathetic Modulation to Exercise Training. Med. Sci. Sports Exerc., Vol. 43, No. 9, pp. 1611-1618, 2011. Purpose: There is a large interindividual variation in the parasympathetic adaptation induced by aerobic exercise training, which may be partially attributed to genetic polymorphisms. Therefore, we investigated the association among three polymorphisms in the endothelial nitric oxide gene (-786T>C, 4b4a, and 894G>T), analyzed individually and as haplotypes, and the parasympathetic adaptation induced by exercise training. Methods: Eighty healthy males, age 20-35 yr, were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis, and haplotypes were inferred using the software PHASE 2.1. Autonomic modulation (i.e., HR variability and spontaneous baroreflex sensitivity) and peak oxygen consumption ((V) over dotO(2peak)) were measured before and after training (running, moderate to severe intensity, three times per week, 60 min.day(-1), during 18 wk). Results: Training increased (V) over dotO(2peak) (P < 0.05) and decreased mean arterial pressure (P < 0.05) in the whole sample. Subjects with the -786C polymorphic allele had a significant reduction in baroreflex sensitivity after training (change: wild type (-786TT) = 2% +/- 89% vs polymorphic (-786TC/CC) = -28% +/- 60%, median +/- quartile range, P = 0.03), and parasympathetic modulation was marginally reduced in subjects with the 894T polymorphic allele (change: wild type (894GG) = 8% +/- 67% vs polymorphic (894GT/TT) = -18% +/- 59%, median +/- quartile range, P = 0.06). Furthermore, parasympathetic modulation percent change was different between the haplotypes containing wild-type alleles(-786T/4b/894G) and polymorphic alleles at positions -786 and 894 (-786C/4b/894T) (-6% +/- 56% vs -41% +/- 50%, median T quartile range, P = 0.04). Conclusions: The polymorphic allele at position -786 and the haplotype containing polymorphic alleles at positions -786 and 894 in the endothelial nitric oxide gene were associated with decreased parasympathetic modulation after exercise training.

Dose-dependent hepatic response to subchronic administration of nandrolone decanoate

Background: Androgenic anabolic steroids (AAS) are synthetic hormone derivatives of testosterone and are mainly used to enhance athletic performance and muscle mass, but medical applications also have been described. Short- and long-term side effects have been demonstrated in many organs, but the liver adverse effects are the most common and serious ones associated with AAS use. However, these effects have been supported by few clinical and experimental studies. Objective: To evaluate the hepatic function and structure after 5 wk of nandrolone decanoate administration at three different doses. Methods: Twenty-seven adult male Wistar rats were randomly assigned to the following groups: control, clinical, intermediate, and suprapharmacological doses of nandrolone decanoate during 5 wk. Results: The biochemical studies showed that nandrolone decanoate administration leads to a dose-dependent increase in serum levels of the aspartate aminotransferase (AST) (P < 0.05), alanine aminotransferase (ALT) (P < 0.01), and alkaline phosphatase (ALP) (P < 0.001), as well as a significant decrease in total proteins (P < 0.01), bilirubin (P < 0.05), total cholesterol and fractions (P < 0.05), and triglycerides (P < 0.05). Although a significant statistical difference was found for AST, ALT, and ALP when compared with the control group, their values remained within the normal range. The number of Kupffer cells was increased in the liver parenchyma (P < 0.05), and the content of collagen was increased in the central lobular vein wall, in the hepatic parenchyma, and in the portal space (P < 0.05). Conclusions: These results suggest that subchronic treatment with nandrolone decanoate, mainly administered at higher-than-clinical doses, are potentially deleterious to the liver, leading to incipient fibrosis.

Low-Intensity Swimming Training Partially Inhibits Lipopolysaccharide-Induced Acute Lung Injury

RAMOS, D. S. C. R. OLIVO. F. D. QUIRINO SANTOS LOPES, A. C. TOLEDO, M. A. MARTINS, R. A. LAZO OSORIO. M. DOLHNIKOFF, W. RIBEIRO, and R. R VIEIRA. Low-Intensity Swimming Training Partially Inhibits Lipopolysaccharide-Induced Acute Lung Injury. Med. Sci. Sports Exerc.. Vol. 42, No. 1, pp. 113-119, 2010. Background: Aerobic exercise-decreases pulmonary inflammation and remodeling in experimental models of allergic asthma. However, the effects of aerobic exercise oil pulmonary inflammation of nonallergic Origin, such as in experimental models of acute long injury induced by lipopolysaccharide (LPS), have not been evaluated. Objective: The present study evaluated file effects of aerobic exercise in a model of LPS-induced acute lung injury. Methods: BALB/c mice were divided into four groups: Control, Aerobic Exercise, LPS, and Aerobic Exercise + LPS. Swimming tests were conducted at baseline and at 3 and 6 wk. Low-Intensity swimming training was performed for 6 wk, four times per week, 60 min per session. Intranasal LPS (1 mg.kg(-1) (60 mu g per mouse)) was instilled 24 It after the last swimming physical test in the LPS and Aerobic Exercise + LPS mice, and the animals were studied 24 It after LPS instillation. Exhaled nitric oxide, respiratory mechanics, total and differential cell Counts in bronchoalveolar lavage, and lung parenchymal inflammation and remodeling were evaluated. Results: LPS instillation resulted in increased levels of exhaled nitric oxide (P < 0.001), higher numbers of neutrophils in file bronchoalveolar lavage (P < 0.001) and in the lung parenchyma (P < 0.001), and decreased lung tissue resistance (P < 0.05) and volume proportion of elastic fibers (P < 0.01) compared with the Control group. Swim training in LPS-instilled animals resulted in significantly lower exhaled nitric oxide levels (P < 0.001) and fewer nelltrophils in the bronchoalveolar lavage (P < 0.001) and the lung parenchyma (P < 0.01) compared with the LPS group. Conclusions: These results Suggest that low-intensity swimming training inhibits lung neutrophilic inflammation, but not remodeling and impaired lung mechanics, in a model of LPS-induced acute lung injury.

Effect of Acute and Chronic Physical Exercise on Patients with Periodic Leg Movements

ESTEVES, A. M., M. T. DE MELLO, M. PRADELLA-HALLINAN, and S. TUFIK. Effect of Acute and Chronic Physical Exercise on Patients with Periodic Leg Movements. Med. Sci. Sports Exerc., Vol. 41, No. 1,. pp. 237-242, 2009. Purpose: Nonpharmacological interventions may lead to an improvement in sleep quality. The objective of our study was to evaluate the effects of acute intensive exercise and chronic exercise on sleep patterns in patients with periodic leg movements (PLM). Methods: The study involved acute and chronic exercise. The acute intensive exercise group consisted of 22 volunteers who underwent a maximum effort test and a polysomnography (PSG) on the same night. The chronic exercise group included. 11 patients who performed 72 physical training sessions undergoing three PSG studies on the night of sessions 1, 36, and 72. Blood samples were collected from both acute and chronic groups for beta-endorphin dosage. Results: Our results showed that both forms of physical exercise lowered PLM levels. The acute physical exercise increased sleep efficiency, rapid eye movement (REM) sleep, and reduced wake after sleep onset, whereas the chronic physical exercise increased sleep efficiency, REM sleep, and reduced sleep latency. We also found a significant negative correlation between beta-endorphin release after acute intensive exercise and PLM levels (r = -0.63). Conclusion: Physical exercise may improve sleep patterns and reduce PLM levels. The correlation between beta-endorphin release after acute intensive exercise and PLM levels might be associated with the impact physical exercise has on the opiodergic system. We suggest that physical exercise may be a useful nonpharmacological treatment for PLM.

Efeitos agudos do alongamento estático no desempenho da força dinâmica em homens jovens

Introdução: O alongamento muscular é frequentemente utilizado nas práticas desportivas, com o objetivo de aumentar a flexibilidade muscular e amplitude articular, assim como diminuir o risco de lesões e melhorar o desempenho atlético. Objetivo: Analisar o efeito agudo do alongamento com diferentes tempos no desempenho da força dinâmica de membros superiores e inferiores em homens jovens. Métodos: Participaram da amostra 14 voluntários do sexo masculino com idade de 23 ± 2 anos, peso corporal de 84 ± 10kg, estatura de178 ± 7cm, IMC de 26 ± 2kg/m2 e percentual de gordura de 11 ± 3%. Eles foram avaliados com o teste de 10RM em três situações distintas: condição sem alongamento (SA), aquecimento especifico seguido do teste de 10-RM; condição com oito minutos de alongamento (AL-8), uma sessão de alongamento estático com oito minutos de duração, seguido do aquecimento e teste de 10RM; e a condição alongamento 16 minutos (AL-16), 16 minutos de alongamento seguidos dos procedimentos descritos anteriormente. Os testes foram feitos no supino reto e leg-press 45º; os alongamentos foram selecionados de forma a atingir as musculaturas solicitadas nos respectivos exercícios. Resultados: Houve redução de 9,2% da força muscular dinâmica de membros superiores em comparação dos grupos SA e AL16, e entre os grupos AL8 e AL16 (p < 0,001). Em membros inferiores essa redução de força (p < 0,001) foi de 4,8% para AL-8 e de 14,3% para AL-16 em comparação com o grupo SA. Conclusão: Sessões de alongamentos estáticos efetuados antes de atividades que envolvam força dinâmica possuem a capacidade de alterar negativamente o desempenho dessa qualidade física, acarretando pior rendimento em longos períodos de alongamento.

Conciliação entre formação esportiva e formação escolar : um estudo das seleções brasileiras masculinas de basquetebol de base

A pesquisa se caracteriza pela abordagem plurimetodológica do tipo qualitativa/quantitativa, e tem como objetivo investigar de que maneira se constroem as estratégias de conciliação entre a formação esportiva e escolar em atletas de elite que servem às seleções brasileiras masculinas de basquetebol Sub 17 e Sub 19. O estudo se organizou em três capítulos. Do tipo “estado do conhecimento”, o primeiro capítulo tem por objetivo mapear as produções acadêmicas que tratam da conciliação entre formação escolar e formação esportiva. Utiliza como fonte a base de dados Scielo para busca nacional e o Portal Periódicos Capes para busca internacional. Foram encontrados 17 artigos distribuídos em 13 periódicos. Os dados foram classificados/analisados por meio de indicadores bibliométricos, como distribuição anual, distribuição por revista, relação autoral e origem demográfica. Para análise também foram levados em consideração uma tese de doutorado, três dissertações de mestrado e três trabalhos apresentados em congresso, além de um número especial de periódico, não localizado nas bases escolhidas. Mostra que a preocupação com o tema surge na Europa e nos Estados Unidos, na década de 70, e que, no Brasil, essa questão passa a ser abordada nos anos 2000. Demonstra tentativas de conciliação entre as formações realizadas em países da Europa, Estados Unidos e Brasil, além da importância da família e do pertencimento de classes sociais na possibilidade de priorização a uma das formações envolvidas. O segundo capítulo, de natureza quali-quantitativa, investiga as estratégias utilizadas pelos atletas convocados em 2013 para as seleções brasileiras de basquetebol masculinas de base Sub 17 e Sub 19 anos, quanto às possíveis conciliações entre formação esportiva e escolar. Busca, ainda, compreender a influência das convocações para as seleções nacionais nos índices de escolaridade desses atletas de elite, como abandono, atraso e repetência escolar. A pesquisa mostra que esse grupo de atletas de elite apresenta médias de repetência, abandono e atraso escolar maiores que as médias nacionais. O terceiro capítulo analisa o entendimento desse grupo de jovens atletas em relação à formação escolar ou, ainda, se um possível desinteresse do grupo pelo modelo atual de escola se daria apenas pelo fato de serem esportistas de elite. Para isso, recorre às possibilidades de investigação oriundas da segunda metade do questionário utilizado como instrumento para adotar uma metodologia de livre associação de palavras direcionadas a partir de quatro palavras indutoras (estruturas semânticas), a saber: “treinar”, “estudar”, “ir a escola” e “competir”. Essa associação livre é usualmente utilizada como suporte teórico/metodológico em pesquisas que investigam representação social (ACOSTA, 2005). Ao dar visibilidade a essas questões nota-se que a posição desses atletas, em relação à escola, não difere das encontradas em outras pesquisas que tratam de jovens inseridos no ensino médio. A falta de significado do que se aprende na escola em relação ao que eles desejam desenvolver como atividade laboral, faz com que a escola seja entendida como monótona, mas, ao mesmo tempo, necessária, caso seus projetos de formação esportiva não aconteçam.