Caffeine supplementation improves physical performance without affecting fatigue level: a double-blind crossover study.

This study examined the effect of caffeine supplementation (CAFF) in a Wingate test (WT), and the behaviour of blood lactate concentrations (BLa) and neuromuscular fatigue (NMF), measured as reduced countermovement jump (CMJ) performance, in response to the WT. In a double-blind crossover study, 16 participants attended the laboratory twice, separated by a 72-hour window. In the sessions, participants first ingested 6 mg·kg-1 of either CAFF or placebo (PLAC), and then performed a WT. BLa was measured before (L-pre), and 0.5 min (L-post-0.5) and 3.5 min (L-post-3.5) after conducting the WT. The CMJ test was conducted before (CMJ pre), after (CMJ post), and 3 min after completing (CMJ post-3) the WT. The results indicated that CAFF enhanced peak power (Wpeak: + 3.22%; p = 0.040), time taken to reach Wpeak (T_Wpeak: -18.76%; p = 0.001) and mean power (Wmean: + 2.7%; p = 0.020). A higher BLa was recorded for CAFF at L-post-0.5 (+ 13.29%; p = 0.009) and L-post-3.5 (+ 10.51%; p = 0.044) compared to PLAC. CAFF improved peak power (PP; + 3.44%; p = 0.003) and mean power (MP; + 4.78%; p = 0.006) at CMJ pre, compared to PLAC, whereas PP and MP were significantly diminished at CMJ post and CMJ post-3 compared to pre (p < 0.001 for all comparisons) under both the CAFF and PLAC conditions. PP and MP were increased at post-3 compared to post (p < 0.001 for all comparisons) for both conditions. In conclusion, CAFF increased WT performance and BLa without affecting NMF measured by CMJ. Thus, CAFF may allow athletes to train with higher workloads and enhance the supercompensation effects after an adequate recovery period.

Upper Limb Anaerobic Metabolism Capacity is Reduced in Mild and Moderate COPD Patients.

Limited information is available regarding the role of anaerobic metabolism capacity on GOLD 1 and 2 COPD patients during upper limb exercise. We aimed to compare the upper limb anaerobic power capacity, blood lactate concentration, cardiovascular and respiratory responses, in male COPD patients versus healthy subjects during the 30-s Wingate anaerobic test (WAnT). The rate of fatigue and time constant of the power output decay (τ, tau) were also calculated and a regression analysis model was built to assess the predictors of τ in these patients. Twenty-four male COPD patients (post-bronchodilator FEV1 73.2 ± 15.3% of predicted) and 17 healthy subjects (FEV1 103.5 ± 10.1% of predicted) underwent the WAnT. Measurements were performed at rest, at the end of the WAnT, and during 3' and 5' of recovery time. Peak power (p = 0.04), low power (p = 0.002), and mean power output (p = 0.008) were significantly lower in COPD patients than in healthy subjects. Power output decreased exponentially in both groups, but at a significantly faster rate (p = 0.007) in COPD patients. The time constant of power decay was associated with resistance (in ohms) and fat-free mass (r2 = 0.604, adjusted r2 = 0.555, and p = 0.002). Blood lactate concentration was significantly higher in healthy subjects at the end of the test, as well as during 3' and 5' of recovery time (p < 0.01). Compared with healthy subjects, COPD patients with GOLD 1 and 2 presented lower upper limb anaerobic capacity and a faster rate of power output decrease during a maximal intensity exercise. Also, the WAnT proved to be a valid tool to measure the upper limb anaerobic capacity in these patients.

Sprint Interval Exercise Performance in Vegans.

OBJECTIVE: The impact of a vegan diet on sprint interval exercise performance is unknown. Thus, the purpose of the present study was to compare performance during a sprint interval exercise between omnivores and vegans. METHODS: Nine healthy omnivores (4 men and 5 women) and nine healthy vegans (4 men and 5 women), with similar levels of daily physical activity, performed four bouts (5-min rest between bouts) of a 30-s all-out sprint exercise on a cycle ergometer. Peak power, mean power, fatigue index, and time to reach maximal power output in each bout were recorded. RESULTS: There was a higher peak power in bouts 1 and 2 compared with bouts 3 and 4 (p < 0.02), and a higher mean power in bout 1 compared with bouts 2, 3 and 4 (p < 0.02). However, for all bouts, there were no significant difference between omnivores and vegans in peak power (7.60 ± 1.55 vs. 8.16 ± 1.27, 7.52 ± 1.6 vs 7.61 ± 0.73, 7.00 ± 1.44 vs. 7.00 ± 1.05 and 6.95 ± 1.42 vs. 6.49 ± 0.90 W.kg-1, all p > 0.05) and in mean power (5.35 ± 0.93 vs. 5.69 ± 0.84, 5.10 ± 0.88 vs. 5.21 ± 0.49, 4.79 ± 0.81 vs. 4.79 ± 0.45 and 4.81 ± 0.81 vs. 4.69 ± 0.47 W.kg-1, all p > 0.05). Fatigue index and time to reach maximal power output were not affected by diet or bouts (all p > 0.05). CONCLUSIONS: These findings indicate that a vegan diet does not compromise sprint interval exercise performance.

Efectos de un programa de ejercicio aeróbico submáximo sobre el rendimiento cardiorrespiratorio y la potencia anaeróbica

Introducción: Existen beneficios en salud al realizar ejercicio físico, sin embargo, son pocas las investigaciones que reportan el rendimiento anaeróbico y su correlación con indicadores cardiorrespiratorios. Por tal motivo, el propósito de esta investigación fue determinar valores de rendimiento cardiorrespiratorio y aptitud anaeróbica después de un programa de ejercicio aeróbico en el cual se determinó la correlación entre ellos. Métodos: 22 hombres (20±2 años) conformaron dos grupos, G1-(entrenamiento), 6 semanas/tres días por semana, intensidad horaria de 45 minutos/día, G2-(Control). Antes y después realizaron un test de Wingate y una prueba de esfuerzo de predominancia aeróbica. Resultados: Aumentos significativos entre el pre-pos en G1 en VO2máx y vatios que mejoraron 7,6 % y 15,9 % respectivamente, diferencia significativa en la PP y en PM/kg con una mejora del 18,8 % y 18,9 %, respectivamente. Conclusión: Un programa de ejercicio aeróbico submáximo en bicicleta estática aumenta el rendimiento cardiorrespiratorio y rendimiento anaeróbico sin que exista una relación de dependencia entre las diferentes variables.

Introduction: There are health benefits when performing physical exercise, however, there are few investigations that report anaerobic performance and its correlation with cardiorespiratory indicators, for this reason, the purpose of this research was to determine the values of cardiorespiratory performance and anaerobic fitness after an aerobic exercise program determining the correlation between them. Method: 22 men (20 ± 2 years), were divided into two groups, G1 (training), 6 weeks, three days a week with an hourly intensity of 45 minutes per day, G2 (control). Before and after exercise they performed a Wingate test and a predominantly aerobic stress test. Results: Significant increases between pre-post in G1 in VO2Max and watts improving 7.6% and 15.9% respectively, a significant difference in PP and PM/kg improving 18.8% and 18.9% respectively. Conclusion: A submaximal aerobic exercise program on a stationary bike increases cardiorespiratory performance and anaerobic performance without a dependency relationship between the different variables.

Effect of low dose, short-term creatine supplementation on muscle power output in elite youth soccer players.

BACKGROUND: To determine the effects of a low dose, short-term Creatine monohydrate (Cr) supplementation (0.03 g.kg.d-1 during 14 d) on muscle power output in elite youth soccer players. METHODS: Using a two-group matched, double blind, placebo-controlled design, nineteen male soccer players (mean age = 17.0 ± 0.5 years) were randomly assigned to either Cr (N = 9) or placebo (N = 10) group. Before and after supplementation, participants performed a 30s Wingate Anaerobic Test (WAnT) to assess peak power output (PPO), mean power output (MPO), fatigue index (FI), and total work. RESULTS: There were significant increases in both PPO and MPO after the Cr supplementation period (P ≤ 0.05) but not the placebo period. There were also significant increases in total work, but not FI, after the Cr supplementation and placebo periods (P ≤ 0.05). Notably, there were differences in total work between the Cr and placebo groups after (P ≤ 0.05) but not before the 14 d supplementation period. CONCLUSION: There is substantial evidence to indicate that a low-dose, short-term oral Cr supplementation beneficially affected muscle power output in elite youth soccer players.

Chronic lactate supplementation does not improve blood buffering capacity and repeated high-intensity exercise.

Since there is conflicting data on the buffering and ergogenic properties of calcium lactate (CL), we investigated the effect of chronic CL supplementation on blood pH, bicarbonate, and high-intensity intermittent exercise performance. Sodium bicarbonate (SB) was used as a positive control. Eighteen athletes participated in this double-blind, placebo-controlled, crossover, fully counterbalanced study. All participants underwent three different treatments: placebo (PL), CL, and SB. The dose was identical in all conditions: 500 mg/kg BM divided into four daily individual doses of 125 mg/kg BM, for five consecutive days, followed by a 2-7-day washout period. On the fifth day of supplementation, individuals undertook four 30-s Wingate bouts for upper body with 3-min recovery between bouts. Total mechanical work (TMW) for the overall protocol and for the initial (1st+2nd) and final (3rd+4th) bouts was determined at each session. Blood pH, bicarbonate, and lactate levels were determined at rest, immediately and 5 min after exercise. CL supplementation did not affect performance (P > 0.05 for the overall TMW as well for initial and final bouts), nor did it affect blood bicarbonate and pH prior to exercise. SB supplementation improved performance by 2.9% for overall TMW (P = 0.02) and 5.9% in the 3rd+4th bouts (P = 0001). Compared to the control session, SB also promoted higher increases in blood bicarbonate than CL and PL (+0.03 ± 0.04 vs +0.009 ± 0.02 and +0.01 ± 0.03, respectively). CL supplementation was not capable of enhancing high-intensity intermittent performance or changing extracellular buffering capacity challenging the notion that this dietary supplement is an effective buffering agent.

Performance and energy systems contributions during upper-body sprint interval exercise.

The main purpose of this study was to investigate the performance and energy systems contribution during four upper-body Wingate tests interspersed by 3-min intervals. Fourteen well-trained male adult Judo athletes voluntarily took part in the present study. These athletes were from state to national level, were in their competitive period, but not engaged in any weight loss procedure. Energy systems contributions were estimated using oxygen uptake and blood lactate measurements. The main results indicated that there was higher glycolytic contribution compared to oxidative (P<0.001) during bout 1, but lower glycolytic contribution was observed compared to the phosphagen system (adenosine triphosphate-creatine phosphate, ATP-PCr) contribution during bout 3 (P<0.001), lower glycolytic contribution compared to oxidative and ATP-PCr (P<0.001 for both comparisons) contributions during bout 4 and lower oxidative compared to ATP-PCr during bout 4 (P=0.040). For the energy system contribution across Wingate bouts, the ATP-PCr contribution during bout 1 was lower than that observed during bout 4 (P=0.005), and the glycolytic system presented higher percentage contribution in the first bout compared to the third and fourth bouts (P<0.001 for both comparisons), and higher percentage participation in the second compared to the fourth bout (P<0.001). These results suggest that absolute oxidative and ATP-PCr participations were kept constant across Wingate tests, but there was an increase in relative participation of ATP-PCr in bout 4 compared to bout 1, probably due to the partial phosphocreatine resynthesis during intervals and to the decreased glycolytic activity.

Análise da validade dos parâmetros absolutos e relativos para o cálculo da potência anaeróbia no RAST / Analysis of the absolute and relative parameters validity for anaerobic power output in RAST

O objetivo do presente estudo foi analisar a validade dos parâmetros de potência absolutos e relativos do Running-based Anaerobic Sprint Test (RAST) com base no teste de Wingate (WAnT). Doze voluntários do sexo masculino com idade de 25,50 anos (± 2,32) realizaram os testes RAST e WAnT. Foram observados valores significativos (p < 0,01) de correlação para a potência máxima absoluta (r = 0,76) e para a potência média absoluta (r = 0,74) dos testes, entretanto, os valores relativos apresentaram correlações não significativas (r = 0,54 e 0,27 respectivamente). Todos os parâmetros analisados apresentaram diferenças significativas (p < 0,01) na comparação entre WAnT e RAST. Desta forma, os resultados sugerem que apenas os parâmetros de potência absoluta do RAST são válidos. Assim ao aplicar o RAST para avaliação e/ou prescrição de treinamento, ou em pesquisas científicas, devem ser usados preferencialmente os parâmetros absolutos do teste.

The aim of the present study was to analyze the absolute and relative parameters validity for Running-based Anaerobic Sprint Test (RAST) based on Wingate test (WAnT). Twelve male volunteers aged 25.50 ± 2.32 years old performed both RAST and WAnT. Significant (p < 0.01) correlation values for the absolute maximum power (r = 0.76) and mean absolute power (0.74) was found but the relative mean values did not showed significant correlations for both maximum (r = 0.54) and average power output (r = 0.27). Significant differences (p < 0.01) between WAnT and RAST were found for all assessed parameters. Therefore, the results of the present study suggest that the RAST should be used with caution for prescription training and evaluation, and acquisition of scientific data. The results also suggest that only the absolute parameters of the test are good predictors of anaerobic power.

Suplementação de cafeína e indicadores de potência anaeróbia / Supplementation of caffeine and anaerobic power indicators

O objetivo foi verificar o efeito da suplementação de cafeína na potência anaeróbia intermitente em ciclistas treinados. Dez atletas foram submetidos a duas sessões experimentais em um modelo randomizado e duplo-cego. Em cada sessão, os participantes ingeriram aleatoriamente uma cápsula de cafeína (6 mg/kg) ou placebo, e, uma hora após realizaram dois testes de Wingate (T1, T2) para a determinação do desempenho anaeróbio, com um intervalo de 4 minutos entre si. A análise estatística, utilizado ANOVA para medidas repetidas, não revelou diferenças significativas entre os testes com cafeína e placebo. Na comparação intra-testes houve redução significativa apenas para a Potência Média (W) entre as sessões com cafeína (T1c: 673,6±59,5 vs T2c: 589,0±58,8). A ingestão oral aguda de cafeína não contribuiu para o aumento no desempenho anaeróbio intermitente, porém, a redução na potência média com o uso da cafeína, pode sugerir uma preferência do metabolismo para os ácidos graxos, o que seria desvantajoso durante esforços máximos intermitentes.

The aim was to investigate the effect of caffeine on anaerobic power intermittently trained cyclists. Ten athletes underwent two experimental sessions in a model randomized double-blind study. In each session, subjects ingested a random capsule caffeine (6 mg / kg) or placebo. One hour after, two tests Wingate were carried (T1, T2) for determining the anaerobic performance with 4 min of rest between each exercise bout. Statistical analysis used ANOVA for repeated measures revealed no significant differences between the caffeine and placebo trials. In comparing intra-tests was significantly reduced only to Mean Power (W) between sessions with caffeine (T1c: 673.6 ± 59.5 vs. T2c: 589.0 ± 58.8). The acute oral intake of caffeine did not contribute to the increase in intermittent anaerobic performance, however, the reduction in average power with the use of caffeine, may suggest a preference for fatty acid metabolism, which would be disadvantageous during intermittent maximal efforts.

Perfil antropométrico e fisiológico de atletas brasileiros de "rugby" / Anthropometric and physiological profile of Brazilian rugby athletes

Rugby is a very popular sport around the world and on the rise in Brazil. It is characterized by the existence of two basic tactics positions (forwards and backs), in which athletes have distinguishing functional demands and physical characteristics. Although the international literature presents a number of interesting data about the physiological and anthropometric profile of these athletes, little attention has been spent to Brazilian athletes. This study aimed to verify the performance of 20 amateur rugby players and to compare the aerobic power (VO2max), anaerobic endurance and isokinetic strength in backs (n = 10) and forwards (n = 10). A computerized gas analyzer (CPX-D - MGC) was used to determine VO2 and VCO2. A Wingate test was used to determine the anaerobic endurance. An isokinetic dynamometer (Cybex Norm) was used to measure isokinetic strength. The body composition was evaluated according to five components of ISAK. The data were compared through Student t test for independent samples (p < 0.05). Our results show a significant difference between backs and forwards in the variables VO2max (47.8 &± 4.5 and 38.8 &± 5.5 ml.kg-1.min-1); 2nd ventilatory threshold (38.3 &± 3.0 and 31.6 &± 4.2 ml.kg-1.min-1); average power (7.5 &± 0.6 and 6.3 &± 1.1 W.kg-1); total work (225.7 &± 18.4 and 187.9 &± 31.7 J.kg-1); body weight (78.5 &± 9.5 and 101.6 &± 12.6 kg); fat mass (24.7 &± 3 , 2 and 29.7 &± 4.6 percent) and muscle mass (48.7 &± 4.2 and 44.5 &± 3.4 percent) respectively (p < 0.05). Thus, there are significant differences, related to the tactic position and function, in Rugby athletes. Furthermore our results shows that even at the amateur level athletes, physiological and anthropometric characteristics are similar when compared to professional level players.

O "Rugby" é um esporte bastante popular internacionalmente e em franca ascensão no Brasil. É caracterizado pela existência de duas posições táticas básicas ("forwards" e "backs"), cujos atletas apresentam demandas funcionais e características físicas distintas. Embora a literatura internacional apresente um número interessante de referências acerca do perfil antropométrico e fisiológico destes atletas, pouca atenção tem sido despendida aos atletas brasileiros. Assim, este trabalho teve como objetivo verificar o desempenho de 20 jogadores amadores de "Rugby" submetidos à ergoespirometria, teste de Wingate e Dinamometria isocinética bem como a comparação entre "backs" (n = 10) e "forwards" (n = 10) para verificar possíveis diferenças entre as posições táticas. Para determinação dos valores de VO2 e VCO2 foi utilizado um analisador de gases computadorizado (CPX-D; MedGraphics Cardiorespiratory Diagnostic Systems) para variáveis de força um dinamômetro isocinético Cybex Norm (Lumex & Co., Ronkonkoma, USA) e para comparações de composição corporal foi aplicada a técnica de cinco componentes da ISAK. A comparação entre os dados foi verificada por meio do teste t de Student para amostras independentes, sendo que para todas as variáveis foi adotado um índice de significância de p < 0,05. Os nossos resultados mostram uma diferença significativa entre "backs" e "forwards' nas variáveis VO2max (47,8 ± 4,5 e 38,8 ± 5,5 ml.kg-1.min-1)...

2º limiar ventilatório (38,3 ± 3,0 e 31,6 ± 4,2 ml.kg-1.min-1) - potência média (7,5 ±0,6 e 6,3 ±1,1 W.kg-1) e trabalho total (225,7 ± 18,4 e 187,9 ± 31,7 J.kg-1) - massa corporal (78,5 ± 9,5 e 101,6 ± 12,6 kg) Massa Adiposa (24,7 ± 3,2 e 29,7 ± 4,6%) Massa Muscular (48,7 ± 4,2 e 44,5 ± 3,4%) respectivamente (p < 0,05). Sendo assim, evidenciamos a existência de diferenças significativas em algumas das variáveis medidas entre atletas de "Rugby' conforme sua função no jogo. Essa evidência mostra que mesmo os atletas sendo de nível amador, as características fisiológicas, antropométricas e mecânicas são semelhantes quando comparadas aos jogadores de nível profissional.

Desempenho da potência anaeróbia em atletas de elite do mountain bike submetidos à suplementação aguda com creatina / Anaerobic power output of elite off-road cyclists with acute oral creatine supplementation

Com o objetivo de investigar os efeitos da suplementação aguda com creatina no desempenho da potência anaeróbia de atletas de elite do mountain bike, 20 atletas em período básico do macrociclo de treinamento foram distribuídos aleatoriamente (duplo-cego) em dois grupos: placebo (PLA, n = 10) e creatina (CRE, n = 10). Foram avaliados quanto à composição corporal (pesagem hidrostática) e potência anaeróbia (teste de Wingate - TW) antes (PRÉ) e depois (PÓS) de sete dias de suplementação. A creatina ou maltodextrina foi usada em três doses diárias de 0,3g/kg de massa corporal diluídos em meio líquido adoçado. Não foram observadas diferenças significativas nas variáveis morfológicas após sete dias de suplementação (PRÉ x PÓS), e os grupos não diferiram apesar da variação percentual (Δ por cento) contrária (positiva para o grupo CRE e negativa para o PLA). A potência anaeróbia pico (PP) e o instante da potência pico (IPP) aumentaram e o índice de fadiga diminuiu do PRÉ para o PÓS-testes no grupo CRE, enquanto que o grupo PLA não apresentou diferenças significantes. A PP apresentou forte tendência em ser maior e o IPP foi maior no grupo CRE comparado com o PLA. Conclui-se que existem evidências de que a suplementação com creatina (0,3g/kg) em curto prazo (sete dias) pode retardar o IPP (CRE 3,0 ± 0,5/3,6 ± 0,8 Δ por cento= 20 por cento) no teste de Wingate em atletas de elite do mountain bike, sugerindo que a suplementação com creatina pode melhorar o desempenho físico quanto à potência anaeróbia durante o trabalho de alta intensidade e curta duração.

In order to investigate the effect of a high dose, acute oral creatine supplementation on anaerobic power of male off-road cyclists, twenty elite athletes training at the basic period were randomly (double-blind) assigned into 2 groups: placebo (PLA n=10) and creatine (CRE n=10). They were submitted to a body composition evaluation (underwater weighting) and Wingate Anaerobic Test (TW) before (PRE) and after (POS) seven days of supplementation. The oral supplements (creatine and maltodextrine) were taken in sweetened vehicle with three equal doses per day (0. 3 g/kg body mass/dose). After a seven-day period, no significant differences were found on morphological variables (PRE x POS) and there was no difference between the groups in spite of the opposite percent variation (Δ percent) (positive for CRE and negative for PLA group). The anaerobic power output (PP) and the moment of pick power (IPP) increased and the fatigue index decreased from PRE to POST tests in CRE group; however, the PLA group did not show significant differences. The PP showed strong tendency to increased values and IPP was greater in the CRE compared with the PLA group. The results of the present study indicated that short-term creatine supplementation (0.3g/kg) can postpone the anaerobic IPP (CRE 3.0 ± 0.5/3.6 ± 0.8 Δ percent= 20 percent) leading to significant improvement on the performance of power output and peak power moment in off-road cyclists.

Avaliação da capacidade anaeróbia de jogadores de futebol através de testemáximo de corrida de Vai-e-Vem / Evaluation of anaerobic capacity in soccer players using a maximal shuttle run test

O objetivo do presente estudo foi verificar se o teste de Vai-e-Vem300mpode ser utilizado para predizer a capacidade anaeróbia, correlacionando com a potênciamédia do teste de Wingate, em um grupo de jogadores de futebol profissional.Participaram do estudo 21 jogadores (21 ± 2 anos; 76,8 ± 7,0 kg; 179,8 ± 6,7 cm)de uma equipe da primeira divisão da Federação Paulista de Futebol. No primeirodia, os participantes realizaram o teste de Wingate e foram determinados o pico depotência relativo, a potência média relativa e o índice de fadiga. No segundo dia,os participantes realizaram o teste de Vai-e-Vem300m, que consistia em corridas devai-e-vem de 20m, na maior velocidade possível, até totalizar a distância de 300 m.Os parâmetros obtidos desse teste foram a duração do Vai-e-Vem300m e a velocidademédia de 20 m (V20m). Antes e após a realização do Vai-e-Vem300m, foramobtidas amostras sangüíneas para determinação da concentração de lactato ([LAC]).Ao realizar a correlação de Pearson entre os parâmetros obtidos no Wingate e noVai-e-Vem300m, apenas a potência média relativa correlacionou significativamente(p<0,05) com a duração do Vai-e-Vem300m (r = - 0,75) e com a V20m (r = 0,72). A[LAC] aumentou significativamente (p<0,05) quando comparados os valores antes(2,1 ± 1,0 mM) e após (14,3 ± 2,4 mM) o Vai-e-Vem300m. Portanto, os resultadosdo presente estudo demonstraram que o teste de Vai-e-Vem300m pode ser utilizadopara predizer a capacidade anaeróbia em jogadores de futebol profissional.

The aim of this study was to investigate whether a 300-m shuttle run testpredicts anaerobic capacity, expressed as mean power output in the Wingate test, in agroup of professional soccer players. Twenty-one soccer players (21 ± 2 years; 76.8 ±7.0 kg; 179.8 ± 6.7 cm) from a first division team of the São Paulo Soccer Federationparticipated in the study. In the first session, the players were submitted to the Wingatetest for the determination of relative peak power output, relative mean power outputand fatigue index. In the second session, the players underwent a shuttle run test whichconsisted of a maximum sprint of 20 m at the highest speed possible until completing adistance of 300 m. The total run time and mean velocity over the 20 m (V20m) wererecorded. Blood samples were collected before and after the 300-m shuttle run test forthe determination of lactate concentration ([LAC]). Pearson’s correlation between theWingate and 300-m shuttle run test variables showed that only relative mean poweroutput was significantly correlated (p<0.05) with total run time (r = - 0.75) and V20m(r = 0.72). [LAC] showed a significant increase (p<0.05) when comparing the valuesobtained before (2.1 ± 1.0 mM) and after (14.3 ± 2.4 mM) the shuttle run test. In conclusion,this study demonstrated that the 300-m shuttle run test can predict anaerobiccapacity in professional soccer players.

Capacidade anaeróbia de atletas adolescentes de futebol em exercício máximo intermitente / Anaerobic capacity of young soccer athletes in maximal intermittent exercise

O futebol é um esporte de característica intermitente no qual as capacidades aeróbia e anaeróbia são fundamentais para o bom desempenho dos atletas. O presente estudo objetivou analisar a capacidade anaeróbia de atletas adolescentes de futebol do sexo masculino em um exercício máximo de característica intermitente. Trinta e cinco atletas adolescentes de futebol (15,37±0,91 anos; 1,72±0,06 m; 64,17±7,32 kg) realizaram um protocolo de exercício constituído de três séries do Teste de Wingate (TW - 30 segundos de exercício máximo em ciclo-ergômetro com uma carga correspondente a 7,5% da massa corporal do sujeito) intervaladas por dois minutos de repouso. São apresentados dados de Potência Pico, Potência Média e Índice de Fadiga verificados em goleiros, laterais, zagueiros, meio-campistas e atacantes, utilizando a ANOVA de um fator para comparação entre as posições. Os valores percentuais (normalizados com base na primeira série do exercício) foram utilizados para verificação da queda de desempenho através da ANOVA para medidas repetidas. Não foram encontradas diferenças entre o desempenho dos atletas das diferentes posições táticas dentro de cada série do exercício intermitente. Entretanto, foi verificada queda percentual significativa (p<0,001) entre os três TW realizados para Potência Pico e Potência Média. O presente estudo vem a preencher uma lacuna na literatura científica quanto à capacidade anaeróbia de atletas adolescentes de futebol do sexo masculino, particularmente relacionada ao TW.

Soccer is a sport with intermittent characteristics which both the aerobic and anaerobic capacities are fundamentals to the high athletes´ performance. The present study aimed to analyze the anaerobic capacity of young male soccer athletes on a maximal exercise of intermittent characteristic. Thirty-five young soccer athletes (15.37±0.91 years; 1.72±0.06 m; 64.17±7.32 kg) performed a protocol consisting in three bouts of Wingate Test (WT - 30 seconds of maximal exercise in cycle-ergometer with a load correspondent to 7.5% of subject body mass) with two minutes of rest intervals. It was presented data from Peak Power, Mean Power and Fatigue Index verified in goalkeepers, sideways, full backs, midfields and forwards, using the one-way ANOVA to comparison between tactical positions. The percentile values (normalized by the first exercise bout) were used to verify the performance fall through a repeated measures ANOVA. It was found no differences between the performances of different tactical positions athletes in each bout of intermittent exercise. But, it was verified significant percentile fall (p<0.001) between three WT performed to Peak Power and Mean Power. The present study comes to fill a gap in the scientific literature on the anaerobic capacity of young male soccer athletes, particularly related to WT.

Anaerobic capacity may not be determined by critical power model in elite table tennis players.

The aim of the present study was to verify the applicability of anaerobic work capacity (AWC) determined from the critical power model in elite table tennis players. Eight male international level table tennis players participated in the study. The tests undertaken were: 1) A critical frequency test used to determinate the anaerobic work capacity; 2) Wingate tests were performed using leg and arm ergometers. AWC corresponded to 99.5 ± 29.1 table tennis balls. AWC was not related to peak (r = -0.25), mean (r = -0.02), relative peak (r = -0.49) or relative mean power (r = 0.01), nor fatigue index (r = -0.52) (Wingate leg ergometer). Similar correlations for peak (r = -0.34), mean (r = -0.04), relative peak (r = -0.49), relative mean power (r = -0.14) and peak blood lactate concentration (r = -0.08) were determined in the Wingate arm ergometer test. Based on these results the AWC determined by a modified critical power test was not a good index for measurement of anaerobic capacity in table tennis players. Key pointsAnaerobic work capacity (AWC) was not good index of anaerobic capacity in table tennis.AWC determined using the table tennis ergometer showed low correlations with the Wingate test measures for cycle and arm ergometry.A sport-specific protocol is required for measuring anaerobic capacity in table tennis.

Heart rate variability analysis in revascularized individuals submitted to an anaerobic potency test.

The objective of this study was to analyze the behavior of autonomic modulation before, during and after the Modified Wingate Test (WanMT), through the analysis of Heart Rate Variability (HRV). Six volunteers between the ages of 40 and 70, post-revascularization procedures (angioplasty and/or surgery, mean duration 10 months), were submitted to supervised training for at least 10 to 14 months. The following protocol, divided into 5 phases, was used: 1) Rest Phase (RP): 180 seconds; 2) Submaximum Phase (SP): 30 seconds; 3) Maximum Phase (MP): 30 seconds; 4) Active Recuperation Phase (ARP); 120 seconds and; 5) Passive Recuperation Phase (PRP): 180 seconds. For the WanMT Test, we selected the load of 3.75% of corporal weight for all volunteers. To analyze the HRV, we used the following parameters: the interval RRr, MNN, SDNN, RMSSD and PNN50. We only observed results for the group according to RMSSD parameters during the rest phase of the test protocol in which the group remained in vagal presence and during all other phases in vagal depression. However, when we analyzed the PNN50, we observed that the group was in medium vagal presence during all of the phases of the test though there was no statistically significant difference (p> 0.05) between the phases. Therefore, we can say that all of the individuals had a similar profile in the autonomic response to the WanMT, confirmed by the parameters studied in the analysis of the HRV in the time domain.