Efeito de diferentes doses de nandrolona associado ao treinamento de força sobre o perfil fenotípico e área de secção transversa do músculo de ratos / Effect of different doses of nandrolone associated with resistance training on muscle phenotypic profi le and cross-sectional area of rats

O presente estudo avaliou a influência de diferentes doses de decanoato de nandrolona (DN) associado ao Treinamento de Força (TF) sobre o fenótipo de fibras e área de secção transversa (AST) do músculo extensor longo dos dedos (EDL) em ratos "Wistar". Os animais foram divididos em sete grupos: controle (GC) e grupos de acordo com a concentração de DN (0,1, 1, 2, 5, 10 e 20 mg/kg) administrada intramuscular 3 vezes/semana. O TF consistiu de saltos em meio líquido (carga 50-70% do peso corporal) 3x/semana, durante cinco semanas. A associação do TF e DN promoveu ação modulatória sobre os tipos de fibras. Houve hipertrofia das fibras de contração rápida (tipo II) em comparação com as fibras de contração lenta (tipo I). Em conclusão, apesar da associação do TF com DN aumentar a AST muscular e alterar o fenótipo das fibras, não houve efeito gradual das doses mais altas.

The aim of the present study was to evaluate the influence of different doses of nandrolone decanoate (ND) associated with Strength Training (ST) on the phenotype of fibers and cross-sectional area (CSA) of the extensor digitorum longus (EDL) in Wistar rats. The animals were divided into seven groups: control (CG) and the groups according to the dose of ND administered (0,1, 1, 2, 5, 10 e 20 mg/kg). The ST consisted of water jumping with loads of 50-70% of their body mass, three times per week during five weeks. The association of ST with ND promoted a modulatory role on the muscle fiber types. There was a hypertrophy of fast twitch fibers (type II) as compared with slow twitch (type I). In conclusion, although the association of ST with ND increased muscle CSA and modified fiber phenotype, there was no additional effect of higher doses.

Immune parameters, symptoms of upper respiratory tract infections, and training-load indicators in volleyball athletes.

BACKGROUND: The control of immunological alterations becomes important during in-season training, as a result of increased incidence of infectious diseases, and may assist in avoiding interruptions to training due to illness. OBJECTIVE: The aim of the present study was to evaluate 28 weeks of chronic immune modulations in female volleyball athletes. METHODS: The sample was composed of twelve athletes aged 19.47 ± 2.49 years, height 1.78 ± 0.08 cm, and body mass 66.77 ± 7.8 kg. Leukocytes, individual immune cell count, interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α plasma cytokines were measured during the competitive period. RESULTS: Results revealed that immune variables were correlated with symptoms of upper respiratory tract infections and training-load indicators, indicating a possible marker of immune status. There was a statistically significant increase in total leukocytes, neutrophils, and monocyte count, a decrease in lymphocytes, and an increase in upper respiratory tract infection symptoms, with no change in IL-2, IL-6, and TNF-α. Correlations between subjective levels of tiredness, total leukocyte count, and neutrophils with upper respiratory tract infection symptoms were observed. CONCLUSION: In conclusion, these correlations can represent important tools to access the immune status of an athlete during long training periods, preventing a possible immunosuppressive status.

Resistance training associated with the administration of anabolic-androgenic steroids improves insulin sensitivity in ovariectomized rats.

The aim of the present study was to investigate the effects of anabolic-androgenic steroids and resistance training (RT) on insulin sensitivity in ovariectomized rats. Adult female Wistar rats were divided into ten experimental groups (n = 5 animals per group): (1) sedentary (Sed-Intact); (2) sedentary ovariectomized (Sed-Ovx); (3) sedentary nandrolone (Sed-Intact-ND); (4) sedentary ovariectomized plus nandrolone (Sed-Ovx-ND); (5) trained (TR-Intact); (6) trained nandrolone (TR-Intact-ND); (7) trained ovariectomized (TR-Ovx); (8) trained ovariectomized plus nandrolone; (9) trained sham; and (10) trained ovariectomized plus sham. Four sessions of RT were used, during which the animals climbed a 1.1 m vertical ladder with weights attached to their tails. The sessions were performed once every 3 days, with between four and nine climbs and with eight to twelve dynamic movements per climb. To test the sensitivity of insulin in the pancreas, glucose and insulin tolerance tests were performed. For insulin sensitivity, there was a statistically significant interaction for the TR-Ovx group, which presented higher sensitivity than the Sed-Intact, Sed-Ovx, and TR-Intact groups. Sed-Intact-ND and TR-Intact-ND groups exhibited higher values of insulin sensitivity than the Sed-Intact group. Except for the TR-Intact group, sensitivity was greater in trained groups than in the Sed-Intact group. There was higher insulin sensitivity in the TR-Intact-ND group than in the Sed-Intact and Sed-Intact-ND groups (P < 0.05). In conclusion, ovariectomy and short-term RT alone induced no change on insulin action. Administration of nandrolone decanoate improved insulin action, mainly when it was associated with RT.

Effects of the neuromuscular training in the cardiorespiratory fitness and body composition of female volleyball athletes / Efeitos do treinamento neuromuscular na aptidão cardiorrespiratória e composição corporal de atletas de voleibol do sexo feminino

As respostas do organismo humano submetido a estímulos diversos, mensuradas através de parâmetros de performance, têm sido objeto de estudo a fim de aprimorar os métodos de treinamento. O objetivo deste estudo foi investigar os efeitos do treinamento neuromuscular na capacidade cardiorrespiratória e composição corporal de atletas de voleibol. Foram avaliadas 11 mulheres, antes e após 12 semanas de treinamento, referente à fase preparatória do ciclo anual de treinamento. O protocolo experimental constou de avaliação da composição corporal (percentual de gordura, massa magra e a gordura corporal) e da aptidão cardiorrespiratória por meio de ergoespirometria em esteira rolante com protocolo contínuo e carga crescente, na qual se determinaram o consumo máximo de oxigênio, a frequência cardíaca máxima, o limiar anaeróbio, a frequência cardíaca do limiar anaeróbio e a velocidade do limiar anaeróbio. O treinamento teve frequência de cinco dias por semana dividido em duas sessões: uma de treinamento de força e outra de treinamento técnico e tático. Após o período estudado ocorreram aumentos (p < 0,05) no consumo máximo de oxigênio (6,5 por cento), no limiar anaeróbio (17,5 por cento), na velocidade do limiar (15,3 por cento) e redução (p < 0,05) na frequência cardíaca máxima (-3,1 por cento). Também houve redução (p < 0,05) no percentual de gordura (-8,2 por cento), na gordura corporal (-7,4 por cento) e aumento (p < 0,05) na massa magra (3,2 por cento). Conclui-se que o treinamento neuromuscular realizado na fase preparatória de treinamento contribuiu para o aumento da capacidade cardiorrespiratória e massa magra e para redução do percentual de gordura e a gordura corporal das atletas de voleibol.

The responses of the human body submitted to several stimuli measured by performance parameters have been object of studies in order to improve training methods. The aim of this study was to investigate the effects of the neuromuscular training in the cardiorespiratory fitness and body composition of volleyball athletes. Eleven women were assessed before and after 12 weeks of training, concerning the preparatory phase of the annual training cycle. The experimental protocol consisted of assessment of the body composition (fat percentage, lean mass and body fat) and of the cardiorespiratory fitness through ergospirometry on treadmill with continuous protocol and increasing load, in which the oxygen maximal uptake, maximum heart rate, anaerobic threshold, heart rate threshold and anaerobic threshold velocity were determined. The training was carried out five times per week and was divided in two sessions: one strength training and the another technical and tactical training. After the studied period, increase (p < 0.05) in oxygen maximal uptake (6.5 percent), anaerobic threshold (17.5 percent), threshold velocity (15.3 percent) and lean mass (3.2 percent) was observed. Reduction (p< 0.05) in maximum heart rate (- 3.1 percent), fat percentage (-8.2 percent) and body fat (-7.4 percent) was observed. It is concluded that neuromuscular training performed in the preparatory phase contributed to increase in the cardiorespiratory fitness and lean mass as well as decrease in fat percentage and body fat of volleyball athletes.

Avaliação da performance neuromuscular de homens diabéticos tipo 2 / Neuromuscular performance avaliation of type 2 diabetics men

Discute-se na literatura, a existência de uma possível relação entre a resistência à insulina e a composição muscular, em indivíduos diabéticos tipo 2. Um percentual relativamente alto de fibras do tipo I associa-se a uma melhor ação da insulina e, aparentemente, uma alta percentagem de fibras do tipo IIB contribui para a hiperinsulinemia. O presente estudo teve como principal objetivo avaliar possíveis alterações na performance neuromuscular de homens diabéticos tipo 2. Os sujeitos experimentais foram homens, com idade entre 42 e 59 anos e sedentários. Foram realizados testes de salto vertical, abdominais e eletrodiagnóstico neuromuscular. Os testes mostraram não haver diferença entre as performances de diabéticos e não diabéticos, sugerindo que a atividade física prescrita para os diabéticos deve seguir os mesmos critérios de quando prescrita para indivíduos não diabéticos.

Discusses in the literature, about a possible relationship between the insulin resistance and the muscular composition, in type 2 diabetics. A percentual relativement high of type II fibers is associate to a better insulin action and, apparentment, a high percentage of type 2B fibers contributes to the hiperinsulinemy. The present study had how principal objective to evaluate possible alterations in the neuromuscular performance of type 2 diabetics men. The experimental subjects have been men, with age between 42 and 59 years old, and sedentary. It has performed tests of vertical jump, abdominal and neuromuscular eletrical diagnostic. The tests indicated there not to be differences among the performances of diabetics and no diabetics, suggesting that the physical activity prescribed to the diabetics must observe the same standards of when it is prescribed to no diabetics subjects.