RESUMO
BACKGROUND/OBJECTIVE: The aim of this study was to compare the acute effects of resistance training to failure (TF) and non-failure (TNF) with volume-load equalization on neuromuscular performance in recreationally resistance-trained adults. METHODS: Twenty-two trained men (age 21.4 ± 2.3 years) were included in a controlled, randomized, and design cross-over investigation with two experimental conditions and one-week of washout interval between them. The participants performed parallel back-squat adopting TF or TNF with volume, intensity, and rest between sets equalized. Countermovement jump (CMJ) height and peak power (PP) were used as mechanical indicators of neuromuscular performance. The mechanical variables were assessed in five moments (pre-experiment, post 15-s, 10-min, 20-min, and 30-min). RESULTS: When compared with the TNF condition, TF presented greater decrement on CMJ height (P < 0.001) and PP (P < 0.001) performance. The CMJ height and PP performance in parallel back-squat exercise following the TNF condition returned to the pre-experiment values 10-min after (P > 0.05). On the other hand, the TF condition promoted greater decrement in CMJ and PP performance compared with the pre-experiment and TNF protocol even 20-30 min later (P < 0.05). CONCLUSION: These findings suggest that TF promotes greater acute impairment on neuromuscular performance even when volume-load is equalized.
RESUMO
The purpose of this study was to determine whether Far-Infrared Emitting Ceramic Materials worn as Bioceramic pants would improve neuromuscular performance, biochemical and perceptual markers in healthy individuals after maximal eccentric exercise. Twenty-two moderately active men were randomized into Bioceramic (n = 11) or Placebo (n = 11) groups. To induce muscle damage, three sets of 30 maximal isokinetic eccentric contractions of the quadriceps were performed at 60°·s-1. Participants wore the bioceramic or placebo pants for 2 hours immediately following the protocol, and then again for 2 hours prior to each subsequent testing session at 24, 48 and 72 hours post. Plasma creatine kinase and lactate dehydrogenase activity, delayed-onset muscle soreness, perceived recovery status, and maximal voluntary contraction were measured pre-exercise and 2, 24, 48, and 72 hours post-exercise. Eccentric exercise induced muscle damage as evident in significant increases in delayed-onset muscle soreness at 24 - 72 hours (p < 0.05) and creatine kinase between Pre to 2, 24, 48 and 72 hours (p < 0.05). Despite the increased delayed-onset muscle soreness and creatine kinase values, no effect of Bioceramic was evident (p > 0.05). Furthermore, decreases in maximal voluntary contraction between Pre and immediately, 2, 24, 48 and 72 hours post (p < 0.05) were reported. However, the standardized difference was moderate lower for lactate dehydrogenase at 24 h (ES = 0.50), but higher at 48 h (ES = -0.58) in the Bioceramic compared to the Placebo group. Despite inducing muscle damage, the daily use of Far-Infrared Emitting Ceramic Materials clothing over 72 hours did not facilitate recovery after maximal eccentric exercise.
RESUMO
Graduated compression stockings have been used as a mechanical method of deep vein thrombosis prophylaxis for several years. Several studies have demonstrated an increase in mean deep venous velocity, reduced venous pooling, improved venous return, and increase blood lactate clearance in subjects who wore graduated compression stockings during exercise. A possible improvement in venous return during and after exercise may facilitate the clearance of metabolites produced during exercise. Also, studies have suggested that compressive clothing can promote tissue regeneration and consequently positively benefit the muscle function following strenuous exercise. However, the results from the previous studies are controversial. Also, the majority of the studies investigated the effects of compression stockings and there is a lack of studies using different compression garments such as compression shorts, shirts and sleeves. Thus, the purpose of this text is to briefly review the possible effects of compression garments on exercise performance and muscle recovery.
RESUMO
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.