Acute effects of a typical rhythmic gymnastic training session on physiological parameters in Olympic athletes

The aim of this study was to evaluate the effects of a day with two separate training sessions (morning and afternoon) of rhythmic gymnastics on erythrocytes, leukocytes, muscle damage, oxidative stress, and hydration of Brazilian team [age 17.7 (±1.1) years; body height 165 (±0.5) cm; body mass 49.7 (±4.2) kg]. Heart rate and session-ratings of perceived exertion were used to monitor training intensity. Blood samples were collected immediately before (M1) and after (M2) the training day for analyzing erythrocytes, leukocytes, plasma creatine kinase activity, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, ferric reducing ability plasma, thyroid-stimulating hormone, and free T4. Saliva was collected for cortisol analysis. After 24 hours rest (M3), blood collection was performed to analyze creatine kinase and lactate dehydrogenase. The moderate-intensity training day induced significant elevations of total leukocytes (5,163.3 to 9,617.8), lymphocytes (1,752.7 to 2,729.7), neutrophils (2,873.9 to 6,163.6), monocytes (255.7 to 519.1), platelets (280,000.0 to 300,666.7), aspartate aminotransferase (13.1 to 25.6), lactate dehydrogenase (102.5 to 249.1), thyroid-stimulating hormone (1.0 to 3.2), and ferric reducing ability plasma (136.8 to 165.4), as well as significant reductions in red cells (4,691,111.1 to 4,497,777.8), hematocrit (42.1 to 39.3), and hemoglobin (12.9 to 12.5) at M2. There were also significant increases in creatine kinase (144.2 to 519.3) and lactate dehydrogenase (102.5 to 538.2) at M3. The average dehydration rate was 1.3%. A moderate-intensity day of training in rhythmic gymnastics of 8h21min duration caused hemolysis, leukocytosis, muscle damage, redox status perturbations, and insufficient hydration status. These findings show that athletes are exposed to physiological vulnerabilities that can possibly harm their performance and health

Effects of creatine supplementation in swimmers: a comparison of performance between elite and amateur athletes, and body composition between acute and chronic supplementation protocols

A suplementação de creatina tem sido considerada importante estratégia ergogênica, uma vez que baixas concentrações musculares desse composto encontram-se entre as principais limitações para o desempenho em atividades de curta duração e alta intensidade. Porém, há controvérsias sobre os resultados obtidos por meio de tal estratégia, pois se acredita que indivíduos sedentários ou atletas amadores apresentariam melhores resultados quando comparados a atletas de elite. Os efeitos das suplementações aguda e crônica de creatina sobre o aumento da massa corporal magra também têm se tornado alvo de constantes investigações científicas, no intuito de se determinar o componente da massa magra responsável por esse incremento. Desta forma, os objetivos do presente trabalho foram avaliar o efeito da suplementação aguda de creatina (20,0 gramas/dia, durante 5 dias) sobre o desempenho em exercícios intermitentes de curta duração e a composição corporal de nadadores de elite (NE) e amadores (NA), bem como investigar a influência da suplementação crônica de creatina (5,0 gramas/dia, durante 45 dias) sobre a composição corporal dos NA. Para tanto, foram estudados 40 nadadores, sendo 22 de elite e 18 amadores, os quais foram subdivididos em grupos creatina (NECR e NACR) ou placebo (NEPL e NAPL). Após o período agudo de suplementação, foram observadas elevações significativas nas excreções urinárias de creatina (0,026 para 8,40; 0,024 para 12,40 gramas/dia) e creatinina (0,99 para 1,90; 1,85 para 2,50 gramas/dia) nos grupos NECR e NACR, respectivamente. Embora a suplementação aguda tenha promovido redução significativa do lactato sanguíneo em alguns momentos do teste de performance no grupo NACR, bem como declínio da amônia plasmática ao final do exercício nos grupos NECR e NACR, não houve melhora nos tempos de natação em nenhum grupo após a suplementação aguda. No que diz respeito à composição corporal houve aumento de água corporal na fase aguda, sem aumento de massa corporal protéica estimada (MCPE), nos NECR e NACR. No período crônico, o grupo NACR apresentou ganhos significativos de massa magra (900 gramas) e MCPE (200 gramas), enquanto o grupo NAPL apresentou reduções significativas nesses parâmetros (1400 gramas e 800 gramas, respectivamente). Tais resultados demonstraram que a suplementação de creatina não promoveu melhora aguda de desempenho em atividades de curta duração e alta intensidade, porém, cronicamente, preveniu perdas de massa magra e MCPE.Effects of creatine supplementation in swimmers: a comparison of performance between elite and amateur swimmers, and body composition between acute and chronic supplementation protocols. Creatine supplementation has been considered an important ergogenic aid, a time that low muscular concentrations of this composition meet enter the main limitations for the performance in short duration and high intensity exercises. However, it has controversies on the results gotten by this strategy, therefore if it believes that sedentary individuais or amateur athletes would present better results when comparative the elite athlete. The effect of the acute and chronic creatine supplementation on the increase of the lean corporal mass also have become target of constant scientific inquiries, in the intention of determining the component of the lean mass responsible for this increment. Of this form, the objectives of the present study had been to evaluate the effect of the acute creatine supplementation (20,0 grams/day, during 5 days) on the performance in short duration intermittent exercises and on body composition of elite swimmers (ES) and amateur swimmers (AS), as well as investigating the influence of chronic creatine supplementation (5,0 grams/day, during 45 days) on body composition of the AS. For in such a way, 40 swimmers, being 22 of the elite and 18 amateur had been studied, which had been subdivided in creatine (CRES and CRAS) or placebo groups (PLES and PLAS). After the acute supplementation period, had been observed significant rises in urinary creatine (0,026 to 8,40; 0,024 to 12,40 grams/day) and urinary creatinine (0,99 to 1,90; 1,85 to 2,50 grams/day) in groups CRES and CRAS, respectively. Although the acute supplementation has promoted significant reduction of blood lactate at some moments of the intermittent test of performance in group CRAS, as well as decline of blood ammonia in the end of the test in CRES and CRAS groups, the acute supplementation did not have improvement in the speed of swimming in no group. In that it says respect to the body composition, was observed an increase in body water in the acute phase, without increment of estimate corporal protein (EPC), in CRES and CRAS. However, in the chronic period, CRAS group presented significant increase of lean body mass (900 grams) and EPC (200 grams), while group PLAS presented significant reductions in these parameters (1400 grams and 800 grams, respectively). Such results had demonstrated that creatine supplementation did not promote acute improvement of performance in intermittent short duration and high intensity performance, although creatine long-term maintenance prevented muscle wasting

Effects of creatine supplementation in swimmers: a comparison of performance between elite and amateur athletes, and body composition between acute and chronic supplementation protocols

A suplementação de creatina tem sido considerada importante estratégia ergogênica, uma vez que baixas concentrações musculares desse composto encontram-se entre as principais limitações para o desempenho em atividades de curta duração e alta intensidade. Porém, há controvérsias sobre os resultados obtidos por meio de tal estratégia, pois se acredita que indivíduos sedentários ou atletas amadores apresentariam melhores resultados quando comparados a atletas de elite. Os efeitos das suplementações aguda e crônica de creatina sobre o aumento da massa corporal magra também têm se tornado alvo de constantes investigações científicas, no intuito de se determinar o componente da massa magra responsável por esse incremento. Desta forma, os objetivos do presente trabalho foram avaliar o efeito da suplementação aguda de creatina (20,0 gramas/dia, durante 5 dias) sobre o desempenho em exercícios intermitentes de curta duração e a composição corporal de nadadores de elite (NE) e amadores (NA), bem como investigar a influência da suplementação crônica de creatina (5,0 gramas/dia, durante 45 dias) sobre a composição corporal dos NA. Para tanto, foram estudados 40 nadadores, sendo 22 de elite e 18 amadores, os quais foram subdivididos em grupos creatina (NECR e NACR) ou placebo (NEPL e NAPL). Após o período agudo de suplementação, foram observadas elevações significativas nas excreções urinárias de creatina (0,026 para 8,40; 0,024 para 12,40 gramas/dia) e creatinina (0,99 para 1,90; 1,85 para 2,50 gramas/dia) nos grupos NECR e NACR, respectivamente. Embora a suplementação aguda tenha promovido redução significativa do lactato sanguíneo em alguns momentos do teste de performance no grupo NACR, bem como declínio da amônia plasmática ao final do exercício nos grupos NECR e NACR, não houve melhora nos tempos de natação em nenhum grupo após a suplementação aguda. No que diz respeito à composição corporal houve aumento de água corporal na fase aguda, sem aumento de massa corporal protéica estimada (MCPE), nos NECR e NACR. No período crônico, o grupo NACR apresentou ganhos significativos de massa magra (900 gramas) e MCPE (200 gramas), enquanto o grupo NAPL apresentou reduções significativas nesses parâmetros (1400 gramas e 800 gramas, respectivamente). Tais resultados demonstraram que a suplementação de creatina não promoveu melhora aguda de desempenho em atividades de curta duração e alta intensidade, porém, cronicamente, preveniu perdas de massa magra e MCPE.Effects of creatine supplementation in swimmers: a comparison of performance between elite and amateur swimmers, and body composition between acute and chronic supplementation protocols. Creatine supplementation has been considered an important ergogenic aid, a time that low muscular concentrations of this composition meet enter the main limitations for the performance in short duration and high intensity exercises. However, it has controversies on the results gotten by this strategy, therefore if it believes that sedentary individuais or amateur athletes would present better results when comparative the elite athlete. The effect of the acute and chronic creatine supplementation on the increase of the lean corporal mass also have become target of constant scientific inquiries, in the intention of determining the component of the lean mass responsible for this increment. Of this form, the objectives of the present study had been to evaluate the effect of the acute creatine supplementation (20,0 grams/day, during 5 days) on the performance in short duration intermittent exercises and on body composition of elite swimmers (ES) and amateur swimmers (AS), as well as investigating the influence of chronic creatine supplementation (5,0 grams/day, during 45 days) on body composition of the AS. For in such a way, 40 swimmers, being 22 of the elite and 18 amateur had been studied, which had been subdivided in creatine (CRES and CRAS) or placebo groups (PLES and PLAS). After the acute supplementation period, had been observed significant rises in urinary creatine (0,026 to 8,40; 0,024 to 12,40 grams/day) and urinary creatinine (0,99 to 1,90; 1,85 to 2,50 grams/day) in groups CRES and CRAS, respectively. Although the acute supplementation has promoted significant reduction of blood lactate at some moments of the intermittent test of performance in group CRAS, as well as decline of blood ammonia in the end of the test in CRES and CRAS groups, the acute supplementation did not have improvement in the speed of swimming in no group. In that it says respect to the body composition, was observed an increase in body water in the acute phase, without increment of estimate corporal protein (EPC), in CRES and CRAS. However, in the chronic period, CRAS group presented significant increase of lean body mass (900 grams) and EPC (200 grams), while group PLAS presented significant reductions in these parameters (1400 grams and 800 grams, respectively). Such results had demonstrated that creatine supplementation did not promote acute improvement of performance in intermittent short duration and high intensity performance, although creatine long-term maintenance prevented muscle wasting

Effects of creatine supplementation on sports performance and body composition of competitive swimmers

O uso da suplementação de creatina, um nutriente encontrado em alimentos de origem animal, com finalidade de se aumentar o desempenho esportivo tem sido frequentemente discutido na literatura científica. O consumo desse composto é justificado pela evidência de que sua depleção resultaria na incapacidade de se ressintetizar ATP nas quantidades necessárias, o que limitaria o desempenho muscular durante atividades de curta duração e alta intensidade. Estudos envolvendo nadadores e suplementação de creatina têm demonstrado resultados controversos, sugerindo a necessidade de se realizarem mais discussões a esse respeito. Desta forma, o presente estudo teve como objetivo avaliar a influência da creatina sobre a performance e a composição corporal de nadadores competitivos após um período agudo de suplementação. Para tanto, dezoito nadadores foram avaliados quanto à composição corporal, concentração sérica de creatinina, excreção urinária de creatina e creatinina, e ao acúmulo de lactato após performance de provas de 50 e 100 metros, e séries repetitivas de 3x3x50 metros nos períodos pré e pós suplementação com creatina ou placebo. A composição corporal foi determinada através de métodos como dobras cutâneas, bioimpedância e densitometria óssea. O treinamento foi padronizado durante todo o experimento. Não foram observadas diferenças estatisticamente significativas nas marcas obtidas em todas as provas, nas concentrações sanguíneas de creatinina e no lactato sanguíneo após a prova de 50 m entre os períodos pré e pós-suplementação, em ambos os grupos. A creatinina e a creatina urinárias aumentaram significativamente após a suplementação no grupo creatina. No período pós suplementação, o acúmulo de ácido lático frente a prova de 100 metros e o exercício repetitivo foi significativamente menor no grupo creatina em comparação ao grupo placebo. Neste mesmo grupo o aumento da massa corpórea, da massa magra e da água corporal foi significativo, porém, não houve diferença significativa na massa muscular e óssea. No grupo placebo, a composição corporal não sofreu alteração significativa após a suplementação. Embora o aumento da água corporal e da creatinina urinária sugiram que a suplementação de creatina tenha promovido um aumento no estoque e utilização desse composto no músculo, acredita-se que o ganho de peso observado neste grupo tenha inibido um possível efeito ergogênico da creatina sobre a performance. O ganho de peso alteraria a flutuação e a hidrodinâmica de tais indivíduos, resultando em maior gasto de energia durante a prática da natação. Em conclusão, os resultados deste estudo sugerem que, em nossas condições experimentais, a suplementação de creatina não pode ser considerada um suplemento ergogênico destinado ao aumento de desempenho e ao ganho de massa muscular em nadadores.This study examined the effect of creatine on exercise performance and body composition of competitive swimmers following an acute supplementation period. Eighteen swimmers were tested for blood lactate after the performance of 50m, 100m and repetitive set of 3x3x50m. Body composition was determined by skinfold, BIA and DEXA. Blood and urine samples were collected to determine creatine and creatinine levels. After the first trial, subjects were evenly and randomly assigned to either a creatine or a placebo group in a double-blind research design. All subjects were provided a standardized training regimen during the study period. No significant differences in performance times, blood lactate after 50m test and serum creatinine were observed between trials in both groups. Blood lactate for 100m e repetitive set were significantly higher in placebo group than creatine group in post supplementation period. Urinary creatinine increased significantly (p<0,05) in creatine group (from 1,36 to 2,72 g/day), suggesting greater creatine utilization in muscle. In creatine group, gains in weight, fat free mass and body water were significant (1,34Kg; 1,50Kg; 1,38L; respectively), but not in muscle mass (0,06Kg). In placebo group, body composition was not significantly altered after the supplementation period. Although the increase of body water and urinary creatinine suggest that the supplementation promotes increases in store and utilization of creatine in muscle, it appears that there is a factor, due to supplementation, able to hamper swimmers performance: gain of weight. Increase in body weight could result in a concomitant increase in drag forces and altered stroke mechanics, and, therefore, in a higher energy expenditure during swimming. In conclusion, the results of this study suggest that creatine supplementation can not be considered an ergogenic aid for performance and gain of muscle mass in well trained swimmers

Creatina: o suplemento nutricional para a atividade física - Conceitos atuais

A creatina, um composto naturalmente encontrado em alimentos de origem animal, tem sido considerada um suplemento nutricional efetivo na otimização do desempenho de atividades físicas. Podendo também ser sintetizada no fígado, rins e pâncreas, a creatina é estocada no músculo esquelético, onde pode se manter na forma livre(40%) ou fosforilada (60%). A creatina fosforilada exerce importante papel na contração muscular, pois se comporta como importante reservatório de energia, utilizado em atividades de curta duração e alta intensidade. São encontrados estoques de aproximadamente 120 g de creatina em um homem de 70 kg, sendo que 95% se encontram no músculo esquelético. Apesar da função energética da creatina na atividade física ser conhecida há décadas, apenas recentemente tem-se dispensado atenção aos possíveis efeitos ergogênicos da suplementação oral desse composto. Essa suplementação parece aumentar os estoques musculares de creatina. Muitos, mas não todos, os estudos disponíveis sugerem que a suplementação de creatina otimizaria o desempenho de atividades de curta duração e alta intensidade, particularmente em exercícios intermitentes com limitados intervalos para repouso. A suplementação aguda de creatina parece provocar aumento de massa magra, porém, esse aumento parece ser conseqüente de um maior acúmulo de água corpórea. A ingestão crônica de suplementos de creatina, em associação com o treinamento de força, poderia aumentar a massa muscular, porém, ainda são necessários mais estudos para confirmar essa hipótese. A ingestão de doses elevadas de creatina por períodos de até 8 semanas, bem como a ingestão de baixas doses por até 5 anos tem sido considerada saudável, não apresentando efeitos colaterais indesejáveis. A decisão de se utilizar a suplementação de creatina como um método de se otimizar o desempenho esportivo deve ser tomada com ponderação, de acordo com a consciência e necessidade de cada indivíduo.Creatine: the nutritional supplement for exercise - current concepts. Creatine, a natural nutrient found in animal foods, is alleged to be an effective nutritional ergogenic aid to enhance sport or exercise performance. It may be formed in kidney and liver from arginina and glicina. Creatine may be delivered to the muscle, where it may combine readily with phosphate to form creatine phosphate, a high-energy phosphagen in the ATP-CP system, and is stored. The ATP-CP energy system is important for rapid energy production, such as in speed and power events. Approximately 120 g of creatine is found in a 70 kg male, 95% in the skeletal muscle. Total creatine exists in muscle as both free creatine (40%) and phosphocreatine (60%). It is only recently that a concerted effort has been undertaken to investigate its potential ergogenic effect relative to sport or exercise performance. It does appear that oral creatine monohydrate may increase muscle total creatine, including both free and phosphocreatine. Many, but not all studies suggest that creatine supplementation may enhance performance in high intensity, short-term exercise task that are dependent primarily on the ATP-CP energy system, particularly on laboratory test involving repeated exercise bouts with limited recovery time between repetitions. Short-term creatine supplementation appears to increase body mass, although the initial increase is most likely water associated with the osmotic effect of increased intramuscular total creatine. Chronic creatine supplementation in conjunction with physical training involving resistance exercise may increase muscle mass. However, confirmatory research data are needed. Creatine supplementation up to 8 weeks, with high doses, has not been associated with major health risks; with low doses, it was demonstrated that in 5 years period supplementation, there are no adverse effects. The decision to use creatine as a mean to enhance sport performance is left to the description to the individual athlete

Relationship between physical fitness and game-related statistics in elite professional basketball players: Regular season vs. playoffs

<div><p>Abstract AIMS This study aimed to verify th erelation ship between of anthropometric and physical performance variables with game-related statistics in professional elite basketball players during a competition. METHODS Eleven male basketball players were evaluated during 10 weeks in two distinct moments (regular season and playoffs). Overall, 11 variables of physical fitness and 13 variables of game-related statistics were analysed. RESULTS The following significant Pearson’scorrelations were found in regular season: percentage of fat mass with assists (r = -0.62) and steals (r = -0.63); height (r = 0.68), lean mass (r = 0.64), and maximum strength (r = 0.67) with blocks; squat jump with steals (r = 0.63); and time in the T-test with success ful two-point field-goals (r = -0.65), success ful free-throws (r = -0.61), and steals (r = -0.62). However, in playoffs, only stature and lean mass maintained these correlations (p ≤ 0.05). CONCLUSIONS The anthropometric and physical characteristics of the players showed few correlations with the game-related statistics in regular season, and these correlations are even lower in the playoff games of a professional elite Champion ship, wherefore, not being good predictors of technical performance.</p></div

Acute leucocyte, muscle damage, and stress marker responses to high-intensity functional training.

BackgroundHigh-intensity functional training (HIFT) has become more popular, and the number of practitioners has increased; however, it remains unclear whether perturbations in the immune parameters occur, even after one single bout. Our aim was to examine acute leucocyte, muscle damage, and stress marker responses following a single 'Cindy' workout session, and compare the results between novice and experienced participants.Material and methodsTwenty-three HIFT practitioners (age 31.0 ± 1.0 years) completed the 'Cindy' workout. They were categorized as novice (3-8 months of experience; n = 10) and experienced (≥18 months; n = 13). White blood cell (WBC) count, plasma creatine kinase (CK) activity, blood cortisol level, and lactate concentration were measured. Blood analysis was performed before (pre-ex), immediately after (post-ex), 30 min after (post-30 min), and 24 h after (post-24 h) a single 'Cindy' workout session.ResultsWBC count was higher post-ex (6.8 to 11.8x103/μL) and returned to baseline values within post-30 min (pConclusionsA single HIFT session elicited significant acute perturbations in WBC count, stress markers, and muscle tissue, which is like other similar regimens. Importantly, the experienced participants showed greater lymphocyte and cortisol responses than the novice ones