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The authors aimed to compare the effects of creatine (Cr) supplementation combined with resistance training on skeletal muscle mass (SMM), total body water, intracellular water (ICW), and extracellular water (ECW) in resistance-trained men as well as to determine whether the SMM/ICW ratio changes in response to the use of this ergogenic aid. Twenty-seven resistance-trained men received either Cr (n = 14) or placebo (n = 13) over 8 weeks. During the same period, subjects performed two split resistance training routines four times per week. SMM was estimated from appendicular lean soft tissue assessed by dual-energy X-ray absorptiometry. Total body water, ICW, and ECW were determined by spectral bioelectrical impedance. Both groups showed improvements (p p p > .05), whereas the SMM/ECW ratio decreased only in the Cr group (p p r = .71). The authors’ results suggest that the increase in muscle mass induced by Cr combined with resistance training occurs without alteration of the ratio of ICW to SMM in resistance-trained men.

O objetivo deste estudo é avaliar o desempenho de praticantes de treinamento com pesos em diferentes períodos do dia. A amostra foi composta por 10 homens treinados (24,4 ± 2,7anos, 80,6 ± 12,7 kg, 180,0 ± 10,8 cm), submetidos ao teste de uma repetição máxima (1RM) para determinação de carga máxima, no exercício supino no banco horizontal. Em seguida, três encontros foram destinados para realização do teste de resistência de força a 80% de 1RM, realizados em diferentes períodos do dia, de maneira aleatória. A análise de variância (ANOVA one-way) foi utilizada para verificar as médias dos grupos nos períodos distintos. Não foram encontradas diferenças no desempenho, independente do horário do dia, manhã (25 ± 4 repetições), tarde (26 ± 7 repetições) e noite (26 ± 7 repetições) em relação ao desempenho obtido (P > 0,05). Assim, sugere-se que o período do dia não influencia o desempenho da força e fadiga de indivíduos jovens treinados.

O objetivo desta revisão sistemática foi identificar o efeito de diferentes protocolos de jejum intermitente no desempenho de força muscular. Buscas conduzidas por dois pesquisadores de forma independente foram realizadas nas bases de dados eletrônicas e repositório: Pubmed, Scielo, Bibilioteca Virtual em Saúde, Cochrane Central Register of Controlled Trials. Foram incluídos estudos desenvolvidos em humanos (≥18 anos), que avaliaram os protocolos de jejum intermitente do Ramadã ou de Alimentação com Restrição de Tempo (ART), em diferentes testes de força muscular. Um total de 1584 estudos foram selecionados e após cumprida todas as etapas de seleção, apenas 19 artigos foram incluídos nesta revisão. O estudo compõe uma amostra total de 486 participantes, com predomínio do sexo masculino 91,8% (n = 446), dos protocolos de jejum intermitente aplicados, ~79% (n = 15) empregaram o Ramadã e ~21 % (n = 4) o ART; o desempenho de força muscular foi avaliado através da força máxima dinâmica e isométrica de diferentes grupos musculares a partir dos testes: 1 Repetição Máxima (1RM), força de preensão manual (FPM), contração voluntária isométrica máxima (CVIM); e da potência, em diferentes testes de salto. Em geral, os resultados dos estudos que compõem esta revisão apresentaram desfechos unânimes para os testes de 1RM e FPM, indicando não haver implicações do jejum intermitente no desempenho da força muscular quando mensurada por estes testes, contrariamente o desempenho de potência e a CVIM os resultados são conflitantes. Considerando que, mesmo com maior parte dos estudos adotando o mesmo protocolo de jejum e estratificando a avaliação por tipo específico de força, era esperado maior uniformidade nos resultados, o que não foi encontrado.

The purpose of the present study was to analyze the effects of the order of resistance training (RT) exercises on hypertrophy in young adult men. Thirty-six young adult men (age, 21.9 ± 2.5 years; body mass, 72.6 ± 12.1 kg, height, 176.9 ± 7.4 cm; body mass index, 23.1 ± 3.3 kg/m2) were randomly assigned to 1 of 2 training groups that performed a 6-week RT program in either (i) a traditional approach starting with multi-joint (MJ) exercises followed by single-joint exercises (SJ) (MJ-SJ, n = 19) or (ii) in reverse order (SJ-MJ, n = 17). Muscle thickness of the biceps brachii and mid-thigh were assessed by ultrasound. Lean soft tissue (LST) was assessed by dual-energy X-ray absorptiometry. Both groups similarly increased (P < 0.05) biceps brachii thickness (MJ-SJ = +14.2%, SJ-MJ = +13.8%). Alternatively, only the MJ-SJ group presented an increase in mid-thigh thickness from pre- to post-training (MJ-SJ = +7.2%, SJ-MJ = +3.9%). Upper limb LSTs (MJ-SJ = +5.2%, SJ-MJ = +7.5%) were statistically similar between conditions, and a trend for significance (P = 0.07) was found for trunk LST (MJ-SJ = +7.2%, SJ-MJ = +1.7%). Nonsignificant pre- to post-training changes were observed for lower limb LSTs (MJ-SJ = +0.7%, SJ-MJ = +1.8%). Our data suggest that both sequences are effective for increasing muscle hypertrophy over a short-term RT period; there may be a potentially beneficial hypertrophic effect for the mid-thigh by performing exercises in a manner that progresses from MJ to SJ exercises.

Introduction Although resistance training (RT) can provide numerous benefits for both men and women, morphological, neuromuscular, metabolic, physiological, and behavioral differences between sexes may influence the magnitude of training responses. Objective To analyze the impact of 16 weeks of progressive RT on strength endurance in untrained men and women. Methods Twenty-eight men and 31 women (18-30 years) underwent a supervised RT program that was divided into two 8-week stages, 3 times per week on nonconsecutive days. The RT program was composed of exercises for different body segments (trunk, upper and lower limbs) that were performed with three sets of 8-12 repetitions maximum (RM), in 10 and 12 exercises, in the first and second stage, respectively. Strength endurance was assessed in 3 exercises (bench press, squat, and arm curl) and in a combination of these exercises through a protocol composed of 4 sets performed to failure with 80% of 1-RM on the baseline, after 8 and 16 weeks of RT. Results Group vs. time interactions (p

The positive regulation of insulin pathway in skeletal muscle results in increased activity of the mammalian target of rapamycin (mTOR), a positive effector of mRNA translation rate and protein synthesis. Studies that assess the activity of this protein in response to chronic high-fat diet (HFD) are scarce and controversial, and to date, there are no studies evaluating the mTOR pathway in infants exposed to gestational and postgestational HFD. This study investigated the effect of maternal HFD on skeletal muscle morphology and on phosphorylation of proteins that comprise the intracellular mTOR signaling pathway in soleus muscle of offspring at weaning. For this purpose, 10 days prior to conception, 39 female Wistar rats were randomly assigned to either control diet (CTL) or HFD. Later, rats were distributed into four groups according to gestational and postpregnancy diet: CTL/CTL (n=10), CTL/HF (n=11), HF/HF (n=10) and HF/CTL (n=8). After 21 days of lactation, pups were killed, and blood samples and soleus and gastrocnemius skeletal muscle were collected for analysis. We observed an influence of maternal postgestational diet, rather than gestational diet, in promoting an obese phenotype, characterized by body fat accumulation, insulin resistance and high serum leptin, glucose, triglycerides and cholesterol levels (P.05). We have also detected alterations on skeletal muscle morphology--with reduced myofiber density--and impairment on S6 kinase 1 and 4E binding protein-1 phosphorylation (P.05). These results emphasize the importance of maternal diet during lactation on muscle morphology and on physiological adaptations of infant rats.

Ergogenic effect of caffeine on performance in middleand long- term exercise Caffeine is a substance that does not have a nutritional value being classified as a pharmacological active alkaloid, with stimulating action on central nervous system (CNS). However, this substance has been considered a nutritional ergogenic, since it is present in several drinks consumed daily, such as coffee, chocolate, teas and some soft drinks with guarana. Its use has been common in sports, specially in last years, particularly for athletes in cycling competitions and middle- and long-distance runners. The ergogenic effect of caffeine on performance has been demonstrated after the acute ingestion of doses of caffeine between 3 and 6 mg/kg of body weight. However, it is not still clear which action mechanisms of caffeine would be involved on performance improvement of long-term exercise. The supposed diuretic effect induced by the use of caffeine has not been confirmed in practice, and it seems that it is related to employment of mega-doses of this substance. Recently, caffeine was removed of the list of the prohibited substances by the World Agency Anti-Doping (WADA). This probably implies a considerable increase of its use by athletes. Thus, it is necessary some cares when using this ergogenic substance, since the disoriented ingestion may contribute to the emergence of collateral effects influencing negatively athlete’s performance.

The purpose of this study was to investigate the effect of hypertrophy-type resistance training (RT) on upper limb fatigue resistance in young adult men and women. Fifty-eight men (22.7±3.7 years, 70.6±9.3 kg, and 176.8±6.4 cm) and 65 women (21.6±3.7 years, 58.8±11.9 kg, and 162.6±6.2 cm) underwent RT for 16 weeks. Training consisted of 10-12 whole body exercises with 3 sets of 8-12 repetitions maximum performed 3 times per week. Before and after the RT intervention participants were submitted to 1RM testing, as well as a fatigue protocol consisting of 4 sets at 80% 1RM on bench press (BP) and arm curl (AC). The sum of the number of repetitions accomplished in the 4 sets in each exercise was used to indicate fatigue resistance. There was a significant (p

The aim of this study was to compare motor performance in modified pull-up (MPU)and flexed knee push-up (FKPU) tests in young women. Thirty-five apparently healthy women (20.1±2.2 years) were submitted to each one of the tests at an interval of48 hours in a random balanced design. Most individuals performed between 0 an d 10 repetitions (86%) of the MPU test, and approximately 17% did not perform even one repetitions. On the other hand, the highest prevalence of outcomes for the FKPUtest was between 16 and 35 repetitions (71%). The Wilcoxon test identified statistically significant differences (p MPU). A moderate agreement (kappa =0.40) was found between the performance in both tests. Negative correlations of low magnitude (r=-0.23 to 0.46) were found between morphological variables (body weight,height, fat mass, and lean body mass) and motor performance in both tests. The results suggest that the FKPU test is presented as a better indicator ofmuscular endurance levels, where as the MPU test seems to better discriminate muscular strength in young women.

Diferentes condições podem alterar as características fisiológicas, metabólicas, nutricionais e morfológicas. Assim, o objetivo desse estudo foi analisar o efeito do treinamento físico, destreinamento e especialmente destreinamento combinado com a suplementação de leucina sobre o peso corporal, composição corporal, homeostase glicêmica e expressão e fosforilação da via de sinalização da proteína alvo da rapamicina em mamíferos (mTOR). Quarenta e seis ratos Wistar adultos machos foram divididos em 4 grupos: 31 ratos foram treinados em esteira por 8 semanas e 15 foram usados como controle (ratos sedentários). Destes, 15 ratos foram eutanasiados imediatamene após o treinamento (grupo treinado = 8 e grupo controle =7), 8 continuaram treinando, 16 foram mantidos sem exercícios (grupo destreinado = 8 e grupo destreinado suplementado com leucina = 7), e os 7 ratos restantes foram usados como controle (ratos sedentários) por mais 6 semanas antes de serem eutanasiados. Os animais do grupo destreinado foram alimentados com uma dieta contendo ~18% de proteínas, suplementados ou não com 5% de leucina. A composição corporal, o consumo alimentar, o volume de adipócitos, a glicose de jejum, o teste oral de tolerância à glicose (TOTG), o teste oral de tolerância à insulina (TTI), a atividade da citrato sintase, as concentrações séricas de leptina, adiponectina, aminoácidos e ácidos graxos não esterificados (AGNE) e a expressão e fosforilação da proteína mTOR foram avaliados. Os resultados de peso corporal, gordura corporal, coxins adiposos epididimal e retroperitoneal, volume de adipócitos, consumo alimentar, concentração sérica de leptina e TOTG foram significantemente menores nos animais treinados do que nos sedentários e destreinados (P < 0,05). Nenhuma diferença significante foi observada nos valores de glicemia de jejum, TTI e AGNE entre os três grupos (P > 0,05). Por outro lado, o grupo treinado apresentou valores significantemente mais altos para a atividade da citrato sintase do que os grupos sedentário e destreinado (P < 0,05). Nenhuma diferença significante (P > 0,05) foi identificada na comparação entre os grupos destreinados (com ou sem suplementação de leucina), incluindo a expressão e fosforilação da proteína mTOR. O exercício moderado exerce um efeito protetor sobre a composição corporal e a homeostase glicêmica, enquanto que a interrupção do treinamento físico teve um efeito negativo sobre essas variáveis. Os resultados sugerem que a suplementação crônica de leucina parece não reduzir os efeitos deletérios do destreinamento. Different conditions may alter physiological, metabolic, nutritional, and morphological characteristics. Thus, the aim of this study was to analyze the effects of training, detraining, and especially detraining combined with leucine supplementation on body weight, body composition, glicemic homeostasis and expression and phosphorylation of mammalian target of rapamycin (mTOR) protein-signaling pathway in epididymal adipose tissue in rats. Fourty-seven male adult Wistar rats were divided into 4 groups: 32 rats were trained on a treadmill for 8 weeks and 15 were used as controls (untrained rats). Of these, 15 rats were euthanized immediately after training (trained group = 8 and control group = 7), 8 continued in training, 16 were caged without exercise (detrained group = 8 and detrained group plus leucine supplementation = 7), and the remaining 7 rats were used as controls (untrained rats) for more 6 weeks before being euthanized. Animals of the detrained groups were fed with a ~18% protein diet supplemented or not with 5% leucine. Body composition, food intake, adipocytes size, fasting glucose, oral glucose tolerance test (OGTT), insulin tolerance test (ITT), citrate synthase activity (CS), serum leptin, adiponectin, amino acids and non-esterified fatty acids (NEFA) concentrations and expression and phosphorylation of mammalian target of rapamycin (mTOR) protein were measured. Body weight, body fat, epididymal and retroperitoneal fats depots, adipocytes size, food intake, serum leptin concentration and OGTT were significantly lower in trained animals than in untrained and detrained (P < 0.05). No significant differences in the fasting glucose, ITT and NEFA among the three groups were observed (P > 0.05). On the other hand, the trained group showed a significantly higher score in the citrate synthase activity than both untrained and detrained groups (P < 0.05). No significant differences (P > 0.05) were identified in the comparisons between detrained groups (with and without leucine supplementation), including of the mTOR protein expression and phosphorylation. Moderate exercise exerted a protective effect on the body composition and glucose homeostasis while sudden discontinuation of physical training had a negative effect on such variables. Our results suggest that chronic leucine supplementation not seems to decrease the deleterious effects caused by detraining.

The objective of this study was to investigate the ergogenic effects of caffeine on motor performance of judo female athletes. Thirteen female athletes (17.6 ± 1.6 years, 58.3 ± 11.4 kg, 162 ± 4.1 cm, 22.5 ± 4 kg/m2), registered in the State Federation of Judo for at least two years, participated in this study. The motor performance was assessed using the Special Judo Fitness Test (SJFT), from which was considered the number of throws in each block, the total number of throws, recovery and final heart rate (HR) and final score in SJFT. The subjects were tested in two different conditions, after ingestion of gelatin capsules of caffeine (6 mg.kg-1) or placebo (dextrose) 60 minutes before testing in a randomized double-blind, crossover study. The number of throws in each block did not differs between the caffeine (CAF) and placebo (PL) conditions (Block A: 4.53 ± 0.51 CAF and 4.46 ± 0.51 PL; Block B: 8.3 ± 0.63 CAF and 8.23 ± 0.72 PL; Block C: 7.23 ± 0.59 CAF and 7.46 ± 0.77 PL), as well as the total number of throws (20.07 ± 1.18 CAF and 20.15 ± 1.67 PL), HR (Final: 190.3 ± 9.63 bpm CAF and 190.69 ± 9.19 bpm PL; Recovery 162.07 ± 13.78 bpm CAF and 164.3 ± 9.64 bpm PL) and final score in SJFT (17.59 ± 1.4 CAF and 17.75 ± 1.98 PL). Ingestion of caffeine did not improve performance during high intensity and short duration exercise in judo fighters

Este estudo investigou o efeito de um longo período de suplementação com creatina monoidratada (Cr m) sobre o trabalho total relativo (TTR) em esforços intermitentes máximos no cicloergômetro de homens treinados. Vinte seis indivíduos foram divididos aleatoriamente em grupo creatina (CR, n=13) e grupo placebo (PL, n=13). Os sujeitos receberam em sistema duplo-cego, doses de Cr m ou placebo-maltodextrina (20 g.d-1 por 5 dias e 3 g.d-1 durante 51 dias subseqüentes). Os grupos tiveram seus hábitos alimentares e sua condição física previamente controlados. Para determinação do TTR os sujeitos foram submetidos a protocolo de exercício em cicloergômetro composto de três Testes de Wingate de 30s separados por dois minutos recuperação, antes e após o período de suplementação. ANOVA, seguido pelo teste post hoc de Tukey, quando p

Este estudo investigou o efeito de um longo período de suplementação com creatina monoidratada (Cr m) sobre o trabalho total relativo (TTR) em esforços intermitentes máximos no cicloergômetro de homens treinados. Vinte seis indivíduos foram divididos aleatoriamente em grupo creatina (CR, n=13) e grupo placebo (PL, n=13). Os sujeitos receberam em sistema duplo-cego, doses de Cr m ou placebo-maltodextrina (20 g.d-1 por 5 dias e 3 g.d-1 durante 51 dias subseqüentes). Os grupos tiveram seus hábitos alimentares e sua condição física previamente controlados. Para determinação do TTR os sujeitos foram submetidos a protocolo de exercício em cicloergômetro composto de três Testes de Wingate de 30s separados por dois minutos recuperação, antes e após o período de suplementação. ANOVA, seguido pelo teste post hoc de Tukey, quando pThis study investigated the effect of long-term supplementation with creatine monohydrate (Cr m) on relative total work (RTW) in intermittent maximal efforts in the cycle ergometer of trained men. Twenty six individuals were randomly divided in creatine group (CR, n=13) and placebo group (PL, n=13). The subjects received in a double-blind manner, doses of Cr m or placebo-maltodextrin (20 g.d-1 for 5 days and 3 g.d-1 for 51 subsequent days). The groups had their alimentary habits and physical fitness controlled previously. For determination of the RTW the subjects were submitted to exercise protocol in cycle ergometer comprised three 30s Anaerobic Wingate Test interspersed with two minutes recovery, before and after the supplementation period. ANOVA, followed by the Tukey post hoc test, when p

Introdução: O envolvimento em exercícios físicos regulares associados aos níveis esperados de vitaminas B12 e D fornecem benefícios relacionados à função cognitiva, alívio dos sintomas da depressão e preservação do desempenho funcional em idosos. Nesse sentido, diferentes modalidades de exercício precisam ser estudadas para que se conheça os seus possíveis efeitos nas diversas variáveis que influenciam a saúde e a qualidade de vida no envelhecimento. Objetivos: A presente tese tem por objetivo geral analisar os efeitos da Dança de Salão (DS) e Treinamento Aeróbio (TA) e das vitaminas B12 e D no desempenho funcional, cognitivo e nos sintomas depressivos de mulheres idosas fisicamente independentes. Esta é composta por dois artigos científicos cujo os objetivos são: 1) Comparar os efeitos da DS e TA e as influências das vitaminas B12 e D no desempenho cognitivo e nos sintomas depressivos de mulheres idosas fisicamente independentes e 2) Comparar os efeitos da DS e TA e as influências das vitaminas B12 e D no desempenho da aptidão física e funcional de mulheres idosas fisicamente independentes. Materiais e Métodos: foram recrutadas 43 idosas, alocadas por conveniência em dois grupos: DS (n=23) e TA (n=20). O desempenho da aptidão física e funcional foram avaliados no momento pré e pós intervenção pelo Short Physical Performance Batterry - SPPB, Teste de Agilidade e Equilíbrio Dinâmico, Teste de Caminhada de 6 min, Teste de Preensão Manual e Isocinético para mensurar a força e potência de membros inferiores e o desempenho cognitivo foi avaliado pelo Montreal Cognitive Assessment (MoCA) e Stroop Task, o rastreio da sintomalogia da depressão pela Geriatric Depression Scale (GDS-15) e as vitaminas B12 e D foram analisadas pela dosagem dos níveis séricos. Resultados: O grupo DS obteve melhor desempenho na variável Stroop-RT p