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Obesity has a complex multifactorial etiology and is characterized by excessive accumulation of adipose tissue. Visceral adipose tissue has deleterious effects on health because it secretes large amounts of inflammatory cytokines. Nutritional calorie restriction associated with strength training may be useful in managing chronic systemic inflammation. This study aimed to evaluate the acute effect of a single strength-training session on plasma adipokine levels in sedentary, overweight, and obese young men. This study included twelve men (Age: [34.95 ​± ​9.77] years; Height: [174.16 ​± ​3.66] centimeter [cm]; Weight: [97.83 ​± ​12.87] kilogram (kg); body mass index [BMI]: [32.30 ​± ​4.51] kg/m2), who performed a single strength training session. The strength training protocol consisted of 4 sets of 12 repetitions in the following six exercises, 45° leg press, bench press, leg extension, machine row, leg curl, and shoulder press. Blood samples were collected before, immediately after, and 1-h subsequent after strength training. The plasma levels of resistin and leptin were measured. A significant decrease in resistin levels were found 1 ​h after the strength training session if compared to levels before the training session (pre-[before] [2 390 ​± ​1 199] picograms per milliliter [pg/mL] vs post-1 h [1-h subsequent] [1 523 ​± ​798],6 ​pg/mL, p ​= ​0.002 8). The plasma leptin levels did not differ at any time point. In conclusion, a very well controlled single session of strength training significantly decreased the plasma levels of resistin without altering the concentration of leptin in overweight and obese individuals. This effect, at least in part, supports the benefits of exercise by reducing the low grade inflammation and insulin resistance in obesity.

Objective: To compare the acute effect of two training protocols until concentric failure (CF) with different intra-set interval (ISI) configurations (20 s and 40 s) on total weight, the total number of repetitions, and time under tension in trained subjects. Methods: Ten men participated in the study (age = 25.1 ± 4.4 years; body mass = 76.5 ± 10.4 kg; height = 175.8 ± 9.3 cm). Two protocols were performed with 4 sets of bench press exercises and differentiated by the ISI: i) Protocol ISI-40 (40 s) - each set consisted of 6 repetitions followed by an ISI of 40 s and completed with repetitions up to CF; ii) Protocol ISI-20 (20 s) - each set consisted of 6 repetitions with ISI of 20 s every 3 repetitions followed by repetitions to CF. The intensity was 10 repetitions maximum, and the rest interval between sets of 80 s. A minimum interval of 48 h was adopted between protocols. Results: There was no significant difference in the number of repetitions (p = 0.074), in the time under tension (p = 0.353) and in the total volume (p = 0.083) between the protocols. Conclusion: The results indicate that the different ISI configurations did not distinctly influence the number of repetitions, time under tension, and total volume.

Introdução: atividades condicionantes são utilizadas por atletas profissionais e amadores antes do treinamento ou competição com o intuito de melhorar do desempenho físico. Objetivo: o objetivo do estudo foi comparar os efeitos de atividades condicionantes de membros superiores e inferiores no desempenho do arremesso do peso. Método: participaram do estudo 13 homens (Idade: 22± 3 anos; Peso: 74,2± 7,4 kg; Estatura: 1,75± 1,3 m). Os participantes realizaram de modo aleatório as situações: Flexão de braços seguido do arremesso do peso; Salto contra movimento seguido do arremesso do peso e Arremesso do peso somente. Cada atividade condicionante foi composta por 3 séries de 10 s com um minuto de intervalo entre as séries. Após três minutos de intervalo os participantes realizaram seis tentativas do arremesso do peso. Resultados: ANOVA não indicou diferença na distância do melhor arremesso ente as situações. De acordo com a análise por erro típico, houve sete respostas positivas após as flexões de braço e cinco após os saltos verticais. Conclusão: os resultados sugerem efeito das atividades condicionantes no desempenho do arremesso do peso sem predomínio de mecanismos centrais ou musculares no desencadeamento da potencialização pós-ativação.

Aim To evaluate the effects of eight weeks of mat Pilates training on selected hematological parameters, i.e. white blood cell, neutrophils, monocyte, lymphocyte, hematocrit, hemoglobin as well as plasma volume variations in healthy, active women. Methods Twenty-eight women physical education students volunteered to participate in the present investigation. They were assigned to two groups: a Pilates training group (n = 14) that followed an 8-week Pilates training program, and a control group (n = 14). Blood samples were collected at rest at two separate occasions before and after Pilates training. Results The Pilates training group had higher values of plasma volume variations and lower values of white blood cell (19.4%), neutrophils (32%), hematocrit (4.3%) and hemoglobin (4.6%) compared to control group (pConclusion The results of the present study suggested that Pilates training could be an effective strategy for increasing plasma volume variations and boosting immune system in healthy active women.

Background This study investigated the effects of two 14-week resistance training protocols with different repetition duration (RD) performed to muscle failure (MF) on gains in strength and muscle hypertrophy as well as on normalized electromyographic (EMG) amplitude and force-angle relationships. Methods The left and right legs of ten untrained males were assigned to either one of the two protocols (2-s or 6-s RD) incorporating unilateral knee extension exercise. Both protocols were performed with 3–4 sets, 50–60% of the one-repetition maximum (1RM), and 3 min rest. Rectus femoris and vastus lateralis cross-sectional areas (CSA), maximal voluntary isometric contraction (MVIC) at 30o and 90o of knee flexion and 1RM performance were assessed before and after the training period. In addition, normalized EMG amplitude-angle and force-angle relationships were assessed in the 6th and 39th experimental sessions. Results The 6-s RD protocol induced larger gains in MVIC at 30o of knee angle measurement than the 2-s RD protocol. Increases in MVIC at 90o of knee angle, 1RM, rectus femoris and vastus lateralis CSA were not significant between the 2-s and 6-s RD protocols. Moreover, different normalized EMG amplitude-angle and force-angle values were detected between protocols over most of the angles analyzed. Conclusion Performing longer RD could be a more appropriate strategy to provide greater gains in isometric maximal muscle strength at shortened knee positions. However, similar maximum dynamic strength and muscle hypertrophy gains would be provided by protocols with different RD.

Abstract This study analyzed the effect of different repetition durations on electromyographic and blood lactate responses of the bench press exercise. Fifteen recreationally trained male volunteers completed two training protocols, matched for intensity (% one-repetition maximum; 1RM), number of sets, number of repetitions, and rest intervals. One of the protocols was performed with a repetition duration of 4 s (2 s concentric: 2 s eccentric; 2:2 protocol), whereas the second protocol had a repetition duration of 6 s (2 s concentric: 4 s eccentric; 2:4 protocol). The results showed higher normalized integrated electromyography (pectoralis major and triceps brachii) for the 2:4 protocol. Blood lactate concentration was also higher in the 2:4 protocol across all sets. These results show that adding 2 s to the eccentric action in matched training protocols increases muscle activation and blood lactate response, which reinforces the notion that increasing repetition duration is an alternative load progression in resistance training.

O objetivo do presente estudo foi mensurar a flexibilidade de crianças e adolescentes de ambos os sexos (7 aos 15 anos de idade), utilizando o teste de Sentar-e-Alcançar (TSA) e outro teste (Banco para a Avaliação da Flexibilidade - BAFLEX) que possibilite controlar as influências das características antropométricas individuais. Participaram do estudo 250 escolares do sexo masculino e feminino, agrupados em cinco faixas etárias: 7, 9, 11, 13, 15 anos. Quando testados pelo TSA, foi verificado um comportamento similar entre os sexos, destacando-se uma diminuição da flexibilidade até os 13 anos e estabilização aos 15 anos de idade. Em relação ao BAFLEX, não foi detectada redução do desempenho, mas sim um aumento da flexibilidade com o avanço da idade. Adicionalmente, as voluntárias apresentaram maiores níveis de flexibilidade que os indivíduos do sexo masculino na faixa etária de 13 anos. O comportamento da flexibilidade foi diferente entre os testes utilizados, reforçando a expectativa de que os resultados do TSA são influenciados por características antropométricas.

O objetivo desse estudo foi verificar em que medida o processo de ensino-aprendizagem-treinamento utilizado em uma equipe feminina de voleibol favoreceu o desenvolvimento do conhecimento tático declarativo das atletas. Doze jogadoras (idade média 13,9 ± 0,3 anos) pertencentes a um clube participaram da pesquisa. Para caracterizar o processo de ensino-aprendizagem-treinamento foram filmadas e posteriormente analisadas 17 sessões consecutivas de treinamento. Para verificar o desenvolvimento do conhecimento tático, utilizou-se o teste validado por PAULA (2001), sendo este aplicado no início e no final das sessões de treino registradas. Na análise das sessões de treino, as atividades relacionadas ao desenvolvimento da capacidade técnica ocuparam 57,5% do tempo total de treinamento, enquanto que em 29,9% do tempo foram desenvolvidas atividades com características de aperfeiçoamento tático. Para o conhecimento tático, não foi verificado aumento em nenhuma das variáveis medidas no teste. Esses resultados demonstraram que o treinador planificou suas sessões de forma a dedicar maior atenção ao componente técnico, sendo este contemplado especialmente através das atividades sem conexão com situações de jogo, como "fundamentos individuais" ou "combinação de fundamentos". A estrutura de treinamento utilizada parece não ter favorecido o aumento do nível de conhecimento tático declarativo no decorrer do período de treinamento avaliado.The aim of this study was to verify the extent to which the teaching-learning-training process used in a female volleyball team promoted the development of the tactical knowledge. Twelve female players (13.9 ± 0.3 years) of a volleyball team participated in the study. To characterize the process of teaching-learning-training were video recorded and subsequently analyzed 17 consecutive sessions of technical-tactical training. The test validated by PAULA (2001) was used to verify the development of the declarative tactical knowledge and it was applied at the beginning and at the end of the registered training sessions. When analyzing the training sessions, activities related to the development of technical capacity occupied 57.5% of total time of training, while in 29.9% of total time was developed activities with tactical characteristics. There was no increase in any of the variables measured in the tactical knowledge test. The results demonstrated that the coach prepared training sessions dedicating more attention to the technical component, which is shown particularly through the activities without association with game situations, as "individual skills" and "skills combination". The training design used does not seem to have helped to increase the declarative tactical knowledge during the study period.

ABSTRACT The aim of this study was to compare the blood lactate concentration in strength training protocols with different muscle action durations in the bench press exercise. Seventeen volunteers performed three protocols with three sets of six repetitions at 60 % of 1RM, three- minute break between sets and different muscle action durations (2-4: 2s concentric and 4s eccentric; 3-3: 3s concentric and 3s eccentric; 4-2: 4s concentric and 2s eccentric). The analysis of blood lactate concentration considered the average values per set in each protocol. The ANOVA two-way of the results showed that the main effect for protocol showed no significant difference between the three protocols (F = 0,75; p = 0,48; power = 0,48; η2 = 0,17), as the interaction among the factors (F = 1,68; p = 0,13; power = 0,09; η2= 0,62). However, there was significant main effect for set (F = 320,23; p = 0,0001; power = 1,00; η2= 0,95). Therefore, resistance training protocols equated with different muscle actions durations shows no differences in blood lactate response and, regardless of the protocol, its concentration increased throughout the three sets performed.