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This study aimed to analyze the effect of aquatic plyometric training (APT) on jump performance in volleyball players. Twelve female athletes (16.6 ± 0.9 years) were assessed through the following jump tests: spike height (SH), squat jump (SJ), countermovement jump (CMJ) and CMJ with an arm swing (CMJA). Jump height in each test and the eccentric utilization ratio (EUR) were the outcome measures. APT consisted of sets of drop jumps for 6 weeks (2 sessions/week) at a water depth of 0.75 m. Tests were performed at the beginning of a five-week pre-season period, before and after APT, and four weeks later for the follow-up. Repeated measures ANOVAs were used to analyze data and Hedges' g to estimate effect size (ES). Performance of all jumps did not change from baseline to Pre-APT. Performance improved in SH (p < 0.001, ES: 1.09), the SJ (p = 0.045, ES: 0.76) and the CMJA (p < 0.001, ES: 0.78) after APT when compared to Pre-APT. No changes were observed after the follow-up period. In conclusion, including six weeks of APT in the training routine of youth volleyball players improved performance of a sport-specific task (SH), the SJ and CMJA, with gains preserved after a four-week follow-up.

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O objetivo do presente estudo foi verificar o desempenho de corrida e natação de guarda-vidas civis após uma temporada de verão em Florianópolis ­ SC. Quatorze guarda-vidas civis (idade: 23.4 ± 5.0 anos; massa corporal: 74.6 ± 8.9 kg; estatura: 176 ± 0.1 cm) realizaram testes de 500m de natação e 1600m de corrida antes e após uma temporada de verão de 5 meses. Não foi realizada nenhuma intervenção na rotina dos guarda -vidas durante esse período. A comparação no desempenho pré e pós temporada foi realizada pelo teste t de Student para dados pareados (bicaudal), enquanto as correlações entre as variáveis foram verificadas pelo coeficiente de correlação de Pearson, com nível de significância de 5% (p < 0.05). Houve piora nos tempos dos testes de 500m de natação (Pré: 501.4 ± 77.9; Pós: 523.1 ± 84.6 s; p < 0.01) e 1600m de corrida (Pré: 371.6 ± 42.3 s; Pós: 393.9 ± 42.7 s; p < 0.01), sem associação entre o tempo de desempenho pré-temporada no teste de natação (r = 0.441, p = 0.115) ou corrida (r = -0.179, p = 0.541) com as magnitudes de piora. Concluiu-se que houve uma piora no desempenho de corrida e natação ao término da temporada de verão nos guarda-vidas civis, o que pode levar a uma perda no rendimento nas atividades que são submetidos rotineiramente. Dessa forma, tornam-se importantes estratégias, como o treinamento sistematizado, para minimizar essa queda no rendimento dos guarda-vidas civis, evitando o risco a si mesmo e a potenciais vítimas.(AU)

: The aim of this study was verify the performance of the running and swimming of civilian lifeguards after a summer season in Florianópolis - SC. Fourteen civilian lifeguards (age: 23.4 ± 5.0 years; body mass: 74.6 ± 8.9 kg; height: 176 ± 0.1 cm) performed tests of 500m swimming and 1600m running before and after a summer season of 5 months. There was no intervention in the routine of the lifeguards during this period. Statistical analysis consisted of a paired t-test (two-tailed) for the pre and post-season comparison, with the correlations between the variables being verified by Pearson's correlation coefficient, with level of significance of 5% (p < 0.05) for all tests. There was an impairment in the 500m swimming test (Pre: 501.4 ± 77.9; Post: 523.1 ± 84.6 s; p <0.01) and 1600m running test (Pre: 371.6 ± 42.3 s; Post: 393.9 ± 42.7 s; p <0.01), without association between the pre-season performance time and the swimming (r = 0.441, p = 0.115) or running (r= -0.179, p = 0.541) impairment magnitudes. It was concluded that running and swimming performance are impaired at the end of the summer season on civilian lifeguards, which could cause a loss of performance in routine activities. Thus, become important strategies, such as systematic training, to minimize this fall in the performance of civilian lifeguards, avoiding the risk to themselves and potential victims. (AU)

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Abstract Aims: The current study aimed to compare the anaerobic power output through the Wingate test in different positions, i.e., standing and seated, and identify the relationship between power-output and body mass. Methods: Eleven male competitive cyclists (age: 30.3 ± 4.7 years; body mass: 73.7 ± 7.7 kg; body fat: 11.3 ± 4.2%) were submitted to two sessions of the Wingate test (WT) in different positions, on different days. Results: The peak power (W), average power (W), relative peak power (W·kg-1), relative average power (W·kg-1), average cadence (rpm), and average velocity (km·h-1) presented significant differences in the standing position compared with the seated position (p < 0.05), 1155 ± 130 vs. 1082 ± 182 (W), 875 ± 96 vs. 818 ± 116 (W), 15.9 ± 1 vs. 15.0 ± 2 (W kg-1), 12.1 ± 1 vs. 11.3 ± 1 (W kg-1), 117.5 ± 7 vs. 109.8 ± 10 (rpm), 37.0 ± 2 vs. 34.6 ± 3 (km·h-1), respectively. However, when controlled the body mass, the differences in variables power output ceased to exist (p > 0.05). The fatigue and peak heart rate (bpm) indices did not present significant differences between the tests (p > 0.05). Conclusions: Sprint performance was improved when the WT was performed in a standing position in competitive cyclists. The study also reports the important relationship between body mass and anaerobic production capacity in the WT, emphasizing that it is desirable an increase in lean body mass and a reduction in fat mass, similar in competitions. We suggest that, for anaerobic assessment in cyclists, the standing position should be used during the WT, to determine the maximum power-output capacity.

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To investigate the presence of a relative age effect (RAE) and the influence of birth quarters (BQ), semesters (S) as well as skeletal maturation on anthropometric characteristics and aerobic peak speed (PST-CAR) in youth male soccer players. Methods: One hundred players were recruited to participate in this study. Players were allocated into 4 BQ's and 2 S. Skeletal maturity status was assessed using the Fels method. Assessments for players included determination of body size and composition and PST-CAR. Results: Overall, more players were born in BQ1 (38 %) and S1 (75%). The likelihood of players born in BQ1 and BQ2 being selected was 3.61 to 4.96 times higher than players in BQ3 and BQ4. Players in BQ4 maturing earlier were biologically older than their peers in BQ1. The players in BQ3 and S2 displayed higher PST-CAR compared with players in BQ2 and S1, respectively. However, players of contrasting skeletal maturity status did not differ in aerobic performance. Conclusion: Our findings indicate that coaches and talent scouts are systematically retaining average and early maturing players born in S1 and excluding late maturing players born in BQ4. However, aerobic performance appeared to be dependent on the relative age, but independent of skeletal maturation during puberty.(AU)

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ABSTRACT This study aimed to analyze the anaerobic performance and muscle activation during a supramaximal cycling test at three different saddle positions. Twelve competitive cyclists completed an incremental cycling test and three 30-s Wingate tests in three different saddle heights (reference, downward, and upward), in a random order, on different days. The saddle height was individually shifted downward and upward (seeing 2.5% of the distance from the pubic symphysis to ground) from the reference position. The electromyographic signal (EMG) data was obtained from the rectus femoris, vastus lateralis, biceps femoris (long head), and gastrocnemius lateralis in order to assess muscle activation during the entire test. The anaerobic variables and the EMG data were divided into six consecutive windows of 5-s. The EMG signals were normalized by the first 5-s window of the reference position to provide the percentage changes throughout the test. The results suggest that during a 30-s Wingate test small changes in saddle height result in greater peak power output (reference=1380±241 W; downward=1497±175 W, p=0.036; upward=1491±225 W, p=0.049) and greater activation period for vastus lateralis (reference=33.6%, downward=33.2%, upward=35.0%; p=0.001) in comparision to rectus femoris (reference=24.5%, downward=25.2%, upward=23.7%), biceps femoris (reference=20.7%, downward=20.8%, upward=19.9%), and gastrocnemius lateralis (reference=21.2%, downward=20.8%, upward=19.9%). The results suggest that small adjustments in saddle height may affect the force-length relationship of the muscles of the lower limb, and consequently their recruitment pattern and their ability to generate force.

RESUMO O presente estudo teve como objetivo analisar o desempenho anaeróbio e a ativação muscular durante um teste de ciclismo supramáximo em três diferentes alturas do selim. Doze ciclistas competitivos completaram um teste incremental em cicloergômetro e três testes de Wingate de 30 s em diferentes alturas do selim (referência, baixa e alta), de forma randomizada, em diferentes dias. A altura do selim foi alterada para baixo e para cima a partir da posição de referência usando como parâmetro o valor referente a (± 2,5%) da distância da sínfise púbica até o solo. O sinal eletromiográfico (EMG) foi obtido dos músculos reto femoral, vasto lateral, bíceps femoral (cabeça longa) e gastrocnêmio lateral. As variáveis anaeróbias e os dados de EMG foram divididos em seis janelas consecutivas de 5 s. Os sinals EMG foram normalizados pela primeira janela da posição de referência para estipular as mudanças percentuais ao longo do teste. Os resultados sugerem que durante o teste de Wingate de 30 s pequenas alterações na altura do selim resultam em aumento da potência pico (referência=1380±241 W; baixa=1497±175 W, p=0,036; alta=1491±225 W, p=0,049) e maior período de ativação percentual para o vasto lateral (referência=33,6%, baixa=33,2%, alta=35,0%; p=0,001) em relação ao reto femoral (referência=24,5%, baixa=25,2%, alta=23.7%), bíceps femoral (referência=20,7%, baixa=20,8%, alta=19,9%) e gastrocnêmio lateral (referência=21,2%, baixa=20,8%, alta=19,9%). Os resultados sugerem que pequenos ajustes na altura do selim podem afetar a relação força-comprimento e, consequentemente, a capacidade de gerar força e o padrão de recrutamento muscular dos membros inferiores.

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Abstract The purpose of this study was to determine the level of agreement between critical power (CP) and intensity corresponding to 50% of the difference (50% ∆) between oxygen uptake (VO2) at lactate threshold (LT) and maximal oxygen uptake (VO2max) in untrained subjects during cycling exercise. Fifteen healthy male subjects (age: 26.0 ± 3.5 years; body weight: 76.6 ± 10.4 kg; height: 178.2 ± 7.6 cm) volunteered to participate in the study. Each subject performed a series of tests to determine LT, VO2LT, CP, VO2CP, 50% ∆, VO250% ∆, and VO2max. The values LT, CP, VO2CP, 50% ∆, VO250% ∆ and VO2max were 109 ± 15 W, 1.84 ± 0.23 L.min-1, 207 ± 17 W, 2.78 ± 0.27 L.min-1, 206 ± 19 W, 2.77 ± 0.29 L.min-1, and 3.71 ± 0.49 L.min-1, respectively. No signficant difference was found between CP and 50% ∆ (t = 0.16; p = 0.87) or between VO2CP and VO250% ∆ (t = 0.12; p = 0.90). However, the bias ± 95% limits of agreement for comparison between CP and 50% ∆ and between VO2CP and VO250% ∆ were 1 ± 27 W (0.3 ± 14.1%) and 0.01 ± 0.24 L.min-1 (0.2 ± 8.9%), respectively. In summary, the mean CP and 50% ∆ values were not significantly different. However, considering the limits of agreement between the two intensities, CP estimated based on 50% ∆ might result in a remarkable error when the absolute variability of individual differences is taken into account.

Resumo A proposta deste estudo foi determinar o nível de concordância entre a potência crítica (PC) e a intensidade correspondente a 50% da diferença (50% ∆) entre o consumo de oxigênio (VO2) no limiar de lactato (LL) e o consumo máximo de oxigênio (VO2max) em sujeitos não treinados durante o exercício de ciclismo. Quinze sujeitos saudáveis do sexo masculino (idade: 26,0 ± 3,5 anos; massa corporal: 76,6 ± 10,4 kg; estatura: 178,2 ± 7,6 cm) participaram deste estudo. Cada sujeito realizou uma série de testes para determinar o LL, VO2.LL, PC, VO2.PC, 50% ∆, VO250% ∆ e VO2max. Os valores de LL, VO2LL, PC, VO2PC, 50% ∆, VO250% ∆ e VO2max foram 109 ± 15 W, 1,84 ± 0,23 L.min-1, 207 ± 17 W, 2,78 ± 0,27 L.min-1, 206 ± 19 W, 2,77 ± 0,29 L.min-1 e 3,71 ± 0,49 L.min-1, respectivamente. Nenhuma diferença significavita foi encontrada entre a PC e o 50% ∆ (t = 0.16; p = 0.87) e entre o VO2PC e o VO250% ∆ (t = 0.12; p = 0.90). Entretanto, o bias ± 95% dos limites de concordância para as comparações entre a PC e o 50% ∆ e entre o VO2PC e o VO250% ∆ foram 1 ± 27 W (0,3 ± 14,1%) e 0,01 ± 0,24 L.min-1 (0,2 ± 8,9%), respectivamente. Em resumo, os valores médios de PC e 50% ∆ não foram significativamente diferentes. No entanto, a PC estimada pelo 50% ∆ pode resultas em um erro significativo quando a cariabilidade individual absoluta é considerada.

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RESUMOO objetivo do presente estudo foi analisar a reprodutibilidade relativa e absoluta do pico de velocidade (PVT-CAR) e da frequência cardíaca máxima (FCmáx) determinados no teste incremental de Carminatti (T-CAR) em jovens militares. Vinte e sete militares do sexo masculino (idade = 19,3±1,1 anos, massa corporal = 69,5±7,7 kg, estatura = 1,76±0,9m, percentual de gordura = 8,9±3,2 %) pertencentes à Marinha do Brasil foram recrutados para participar deste estudo. Os participantes foram submetidos a duas sessões de avaliação, separadas por 48 horas, para a determinação do PVT-CAR e FCmáx a partir do protocolo do T-CAR. Os testes foram realizados nomes no horário, como intuito de minimizar a interferência das variações biológicas. Não foi encontrada diferença significativa para o PVT-CAR (t=0,773; p=0,446) e FCmax (t=0,543; p=0,592) entre a situação de teste e reteste. Além disso, o coeficiente de correlação intraclasse (CCI) do PVT-CARe FCmax foram 0,73 e 0,90, com um coeficiente de variação do erro típico de medida (CVETM) de 1,55% e 1,28%, respectivamente. As análises de Bland-Altman para o PVT-CAR e FCmax também sugerem que houve boa concordância para essas medidas em condições repetidas. Desta forma, os resultados do presente estudo mostram que houve uma baixa variação intra-individual para o PVT-CARe FCmax, resultando em evidências consistentes de reprodutibilidade absoluta (CVETM) erelativa (CCI). Como aplicação prática,o T-CAR parece ser uma estratégia interessante para avaliar a máxima velocidade aeróbia de jovens militares em diferentes momentos do planejamento anual de treinamento.

ABSTRACTThe purpose of this study was to analyse the relative and absolute reliability of peak velocity (PV) and heart rate maximum (HRmax) derived from Carminatti's incremental test (T-CAR) in young military. Twenty-seven healthy male (age = 19.3 ± 1.1 years, body mass = 69.5 ± 7.7 kg, height = 1.76 ± 0.9 m, body fat percentage = 8.9 ± 3.2 %) belonging to Brazil's Navy were recruited to participate in the current study. Participants performed two assessment sessions, separated by 48 h, to determine the PVT-CAR and HRmax from the T-CAR protocol. The tests were performed on the same day time, in order to minimize the interference of biological variations. There was no significant differences for PVT-CAR (t=0.773; p=0.446) and HRmax (t=0.543; p=0.592) between the test-retest situation. The intraclass correlation coefficient (ICC) for PVT-CAR and HRmax were 0.73 and 0.90, with a coefficient of variation of the typical error of measurement (CVTETM) of 1.55% and 1.28%, respectively. In addition, Bland-Altman plots for PVT-CAR and HRmax suggest that there was acceptable agreement for these measures in repeated conditions. In conclusion, our finding show that there was a low intra-individual variation for PVT-CAR and HRmax, resulting in consistent evidence of absolute (CVETM) and relative (ICC) reliability. As a practical application, the T-CAR test seems to be an interesting alternative to evaluate the maximal aerobic speed of young military at different moments of the annual training planning.

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The aim of this study was to investigate the effects of short repeated-sprint ability (RSA) training on the neuromuscular and physiological indices in U17 futsal players during the competitive period. Fourteen players were divided into two groups: intervention group (n = 8) and control group (n = 6). Both groups performed a repeated maximal sprint test (40-m MST), intermittent shuttle-running test (Carminatti's test) and vertical jumps before and after the training period. The intervention group was submitted to an additional four-week repeated sprints program, twice a week, while the control group maintained their normal training routine. There was no significant interaction between time and groups for all variables analysed (p > 0.05). However, a significant main effect was observed for time (p < 0.01) indicating an increase on speed at heart rate deflection point (VHRDP) and the continuous jump performance while the peak lactate (40m-LACpeak) and sprint decrement decreased after training, in both groups. Still, based on effect sizes (ES) the greater changes with practical relevance were verified for intervention group in important variables such as peak velocity (ES = 0,71), VHRDP (ES = 0,83) and 40m-LACpeak (ES = 1,00). This study showed that RSA-based and normal training routine are equally effective in producing changes in the analysed variables during a short period of intervention. However, the effect size suggests that four weeks of RSA training would be a minimum time that could induce the first changes of futsal player's physical fitness.

O objetivo deste estudo foi investigar os efeitos do treinamento de sprints repetidos (RSA) nos índices fisiológicos e neuromusculares em atletas de futsal sub17 durante a temporada competitiva. Quatorze jogadores foram divididos em dois grupos: grupo intervenção (n = 8) e controle (n = 6). Ambos os grupos desempenharam testes de sprints máximos repetidos (40-m MST), teste de corrida intermitente (teste de Carminatti) e saltos verticais antes e depois do período de treinamento. O grupo intervenção foi submetido a um programa adicional de quatro semanas de RSA, duas vezes por semana, enquanto o grupo controle manteve a rotina normal de treinos. Não houve interação significante entre tempo e grupo para todas as variáveis analisadas (p > 0.05). Entretanto, um efeito principal significante foi observado para o tempo (p < 0.01), indicando um aumento na velocidade do ponto de deflexão da frequência cárdica (VHRDP) e na performance do salto contínuo, bem como, diminuição no pico de lactato (40m-LACpeak) e no decréscimo dos sprints após o treinamento em ambos os grupos. Ainda, baseado no effect size (ES), maiores mudanças com relevância prática foram verificadas para o grupo intervenção em importantes variáveis tais como: pico de velocidade (ES = 0,71) VHRDP (ES = 0,83) e 40m-LACpeak (ES = 1,00). Este estudo demonstrou que o treinamento de RSA e a rotina normal de treinos são igualmente efetivos em produzir mudanças nas variáveis analisadas durante um curto período de intervenção. Porém, o effect size sugere que quatro semanas de treinamento de RSA pode ser um tempo mínimo para que ocorram as primeiras alterações no desempenho físico de atletas de futsal.

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Os objetivos deste estudo foram: determinar e comparar índices fisiológicos obtidos em teste de laboratório e pista (teste de pista da Universidade de Montreal - UMTT) em corredores de endurance; analisar a capacidade de predição do VO2max, vVO2max e LAn determinados no laboratório e no UMTT para a performance nas distâncias de 1.500 m, 5.000 m e 10.000 m; analisar os efeitos da distância da prova na relação entre os índices fisiológicos VO2max, vVO2max e LAn com a performance. Participaram deste estudo, 10 corredores moderadamente treinados que realizaram os seguintes testes: provas simuladas nas distâncias de 10.000 m, 5.000 m e 1.500 m; dois testes incrementais máximos (laboratório e pista) para determinar os índices VO2max, vVO2max e LAn. Não houve diferenças significativas entre o VO2max, vVO2max e LAn determinados em ambos os protocolos. De acordo com a análise de regressão múltipla, referente ao teste de laboratório, a vVO2max foi a única variável selecionada para explicar a performance nas provas de 1.500 e 5.000 m (62 e 35%, respectivamente). Do mesmo modo, dentre as variáveis determinadas no UMTT, somente a vVO2max explicou a performance nestas distâncias (78 e 66%, respectivamente). Por outro lado, o LAn determinado no laboratório e no UMTT explicou 38 e 52% da performance nos 10.000 m, respectivamente. Pode-se concluir que a predição da performance aeróbia de corredores de endurance moderadamente treinados, a partir do VO2max, vVO2max e LAn, determinados em laboratório e no UMTT, é dependente da distância da prova analisada.

The objectives of this study were: 1) determine and compare physiological indexes from laboratory and track tests (Université de Montréal Track Test - UMTT) in endurance runners; 2) analyze the predictive capacity of VO2max, vVO2max and AT with the running performance at 1,500 m, 5,000 m and 10,000 m time trials; 3) analyze the effects of running distance on the relationship between the physiological indexes with aerobic performance. The study included 10 moderately trained endurance runners who performed the following series of tests on different days: 10,000 m, 5,000 m, and 1,500 m time trials on a 400 m track; two maximal incremental tests (laboratory and track) to determine the VO2max, vVO2max, and AT. There were no significant differences between VO2max, vVO2max and AT determined in both protocols. The multiple regression analysis revealed that vVO2max was the only index from laboratory associated with running performance at 1,500 and 5,000 m (62 and 35%, respectively). In addition, vVO2max from UMTT explained the running performance for the same previous distance (78 and 66%, respectively). On the other hand, the AT determined in both incremental tests explained 38 and 52% of performance at 10,000 m time trial, respectively. Thus, the prediction of endurance performance of long distance runners using VO2max, vVO2max and AT determined in the laboratory and UMTT tests depends on the running distance.

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A resposta cardiorrespiratória durante exercícios submáximos, na intensidade da máxima fase estável de lactato (MFELint) até a exaustão, tem sido pouco investigada. O objetivo deste estudo foi investigar a resposta do consumo de oxigênio (VO2), frequência cardíaca (FC) e pulso de oxigênio (pulso O2) em exercício realizado na MFELint até a exaustão, e comparar o gasto energético (GE) estimado pelo VO2 e pela FC. Doze sujeitos treinados realizaram um protocolo incremental em cicloergômetro para determinar parâmetros máximos e submáximos do metabolismo aeróbio. Posteriormente, foram realizados 2 a 4 testes de 30 min com carga constante para identificar a MFELint. Finalmente, os sujeitos realizaram um teste até a exaustão na MFELint. Os parâmetros cardiorrespiratórios foram medidos continuamente durante todos os testes. No teste de exaustão, as respostas fisiológicas foram comparadas entre seis momentos relativos do tempo de exaustão (TTE). O TTE médio foi 55,1±10,2 min. O pulso de O2 apresentou reduções significativas ao longo do tempo, atingindo, no momento da exaustão, um valor ~ 9% inferior comparado ao início do exercício. Este fato ocorreu pelo aumento da FC ao longo do tempo de forma desproporcional ao aumento do VO2, resultando em diferenças significantes entre os GE estimados. Portanto, em exercício realizado na MFELint até a exaustão, parece existir uma perda gradual da eficiência cardiorrespiratória, evidenciada pela redução do pulso O2. Assim, a relação direta entre VO2 e FC com a carga de trabalho é alterada ao longo do exercício, conduzindo a erros de estimativa do GE a partir dos valores da FC.

There has been little research regarding cardiorespiratory responses during submaximal exercise at the maximal lactate steady state intensity (MLSSint) until exhaustion. The objective of this study was to investigate the responses of oxygen consumption (VO2), heart rate (HR) and oxygen pulse (O2 pulse) during exercise to exhaustion at MLSSint, and to compare energy expenditure (EE) estimated by VO2 and HR. Twelve trained athletes followed an incremental protocol on a cycle ergometer to determine maximal and submaximal parameters of aerobic metabolism. On subsequent occasions they performed 2 to 4 30-minute tests with constant load to identify MLSSint. Finally, they underwent a test to exhaustion at MLSSint. Cardiorespiratory parameters were measured continuously during all tests. During the test to exhaustion, physiological responses were compared for six points in time calculated as percentages of the time to exhaustion (TTE). Mean TTE was 55.1±10.2 min. Oxygen pulse presented significant reduction over time, decreasing to a value 9% lower than baseline at the exhaustion point. This fact was the result of increases in HR over time that was disproportional to the increase in VO2, resulting in significant differences between EE estimates. Therefore, there appears to be a gradual loss of cardiorespiratory efficiency during exercise to exhaustion at MLSSint that is shown by the reduction in O2 pulse. The direct relationship between VO2 and HR with workload presents variations over the course of exercise, leading to errors when EE is estimated using HR.