Effect of Vertical Jump and Sprint Training on Power and Speed Performance Transfer.

The aim of this systematic review was to investigate the effect of specific sprint and vertical jump training interventions on transfer of speed-power parameters. The data search was carried out in three electronic databases (PubMed, SCOPUS, and SPORTDiscus), and 28 articles were selected (13 on vertical jump training and 15 on sprint training). We followed the PRISMA criteria for the construction of this systematic review and used the Physiotherapy Evidence Database (PEDro) scale to assess the quality of all studies. It included studies with a male population (athletes and nonathletes, n = 512) from 18 to 30 years old who performed a vertical jump or sprint training intervention. The effect size was calculated from the values of means and SDs pre- and posttraining intervention. The percentage changes and transfer of training effect were calculated for vertical jump training and sprint training through measures of vertical jump and sprint performance. The results indicated that both training interventions (vertical jump training and sprint training) induced improvements in vertical jump and linear sprint performance as well as transfer of training to speed-power performance. However, vertical jump training produced greater specific and training transfer effects on linear sprint than sprint training (untrained skill). It was concluded that vertical jump training and sprint training were effective in increasing specific actions of vertical jump and linear sprint performance, respectively; however, vertical jump training was shown to be a superior alternative due to the higher transfer rate.

Acute and Delayed Effects of Fatigue on Ground Reaction Force, Lower Limb Stiffness and Coordination Asymmetries During a Landing Task.

Landing is a critical phase of movement for injury occurrence, in which lower limbs should be used equally to better absorb the shock. However, it has been suggested that fatigue can lead to the appearance of asymmetries. The aim of this study was to verify the acute and delayed effects of fatigue on the lower limb asymmetry indexes of peak ground reaction force, leg stiffness and intra-limb coordination during a landing task. Fifteen physically active men performed a fatigue protocol composed of 14 sets of 10 continuous vertical jumps, with a one-minute rest interval between the sets. A step-off landing task was performed before, immediately after, 24 h and 48 h after the fatigue protocol. Two force plates and a video analysis system were used. The symmetry index equation provided the asymmetry indexes. For statistical analysis, ANOVA and effect size analysis were utilized. Inferential statistics did not show the effect of fatigue in the asymmetry indexes for any variable or condition (p > .05). Moderate effect sizes were observed for peak ground reaction force (0.61) and leg stiffness (0.61) immediately after the application of the protocol. In conclusion, fatigue does not seem to significantly change the asymmetries of lower limbs, especially regarding intra-limb coordination. The moderate effects observed for peak ground reaction force and leg stiffness asymmetries suggest that these variables may be acutely affected by fatigue.

Effects of successive judo matches on interlimb asymmetry and bilateral deficit.

OBJECTIVE: To verify the effects of successive judo matches on interlimb asymmetry and bilateral deficit in judo athletes. DESIGN: Repeated measures; SETTING: University Judo center. PARTICIPANTS: Fourteen male judo athletes. OUTCOME MEASURES: Four simulated matches consisting of 4-min. Before the first match and after each match athletes were submitted to single leg tests - Countermovement Jump (SLCMJ) and Standing Long Jump (SLSLJ), and handgrip strength (HGS) in the dominant and non-dominant limbs. Interlimb asymmetry was calculated in both jumps and handgrip strength tests. RESULTS: Most jump-derived variables did not change the magnitude of asymmetry throughout the matches (p > 0.05), with the exception of jump height asymmetry in SLCMJ, that increased after the second match (p = 0.001). The HGS decreased in both hands from the first match (p < 0.001), without asymmetry. The highest bilateral strength deficit was observed in post-match 1 and post-match 2 (close to 10%). CONCLUSION: Four-successive judo matches did not change the magnitude of interlimb asymmetry, with exception of SLCMJ height, which increased after the second match. The handgrip strength decreased throughout the matches, but similarly in both hands. Finally, the direction of asymmetry showed consistency throughout the matches only for SLCMJ height.

Reliability and sensitivity of countermovement jump-derived variables in detecting different fatigue levels / Reprodutibilidade e sensibilidade das variáveis derivadas do salto com contra movimento na detecção de diferentes níveis de fadiga

ABSTRACT The aim was to verify the reliability and sensitivity of countermovement jump (CMJ) derived variables in detecting small, moderate and large changes and whether the capacity of CMJ-derived variables in detecting fatigue is dependent of the volume of the fatiguing exercise. Seventeen physically active men performed two fatigue protocols, on separate weeks, composed by continuous vertical jumps: short protocol (7 x 10 jumps) and long protocol (14 x 10 jumps). Jump height (JH), power output (PO), impulse (IMP) and vertical stiffness (KVERT) were measured during CMJ prior to and immediately after the fatigue protocols. Intraclass coefficient correlation, typical error, smallest worthwhile change and magnitude-based inference were analyzed. PO and JH presented excellent reliability and good sensitivity to detect small and medium changes, respectively. Negative effects of fatigue could be detected most likely by PO, regardless of fatiguing exercise volume. JH and IMP seem to be affected only after long protocol and KVERT only after short protocol. In conclusion, PO (peak and mean) is the better marker in CMJ with excellent reliability and sensibility, which allows detect even the small effects and differentiate the fatigue levels.

RESUMO O objetivo foi verificar a reprodutibilidade e a sensibilidade de variáveis derivadas do salto com contra movimento (CMJ) na detecção de pequenas, moderadas e grandes alterações e se a capacidade das variáveis em detectar fadiga é dependente do volume do exercício fatigante. Dezessete homens fisicamente ativos realizaram dois protocolos de fadiga, em semanas separadas, compostos por saltos verticais contínuos: protocolo curto (7 x 10 saltos) e protocolo longo (14 x 10 saltos). A altura do salto (JH), a potência (PO), o impulso (IMP) e a rigidez vertical (KVERT) foram mensurados durante o CMJ antes e imediatamente após os protocolos de fadiga. Foram avaliados o coeficiente de correlação intraclasse, erro típico de medida, mínima mudança valiosa e magnitude baseada em inferência. PO e JH apresentaram excelente reprodutibilidade e boa sensibilidade para detectar pequenas e médias alterações, respectivamente. Os efeitos da fadiga podem ser detectados mais provavelmente pela PO, independentemente do volume de exercício fatigante. JH e IMP parecem ser afetados somente após protocolo longo e KVERT somente após protocolo curto. Em conclusão, PO (pico e média) é o um marcador melhor durante o CMJ com excelente reprodutibilidade e sensibilidade, o que permite detectar até mesmo pequenos efeitos e diferenciar níveis de fadiga.

Is technical performance related to the distance covered during U-19 futsal matches? / A performance técnica está relacionada com a distância percorrida em jogos de futsal da categoria sub-19?

Abstract The aim of the present study was to quantify the physical demand in terms ofdistance covered and to verify the relation with technical performance during simulated futsal matches of U-19 category. Sixteen players participated in the study. Two simulated matches were performed, and the physical demand was quantified by the total distance covered, distance covered per minute and distance at different intensities. In addition, technical performance variables were analyzed during matches. The total distance covered was, on average, 3259.97 ± 180.27 m, with 113.26 ± 6.11 m / min. Approximately 26% of the total distance was covered at high intensity (i.e.,> 15 km.h-1), with significant decrease of these actions in the second half of matches (p <0.05). There were no significant correlations between physical and technical performance variables. However, there were positive correlations classified as "strong" of technical variable "unsuccessful kicks" with the total distance covered during match. This study demonstrated that simulated futsal matches of the U-19 category present high physical demand, with values of distance covered per minute at different intensities similar to those found in professional Brazilian players during official matches. There were no significant correlations between physical and technical performance during matches; however, correlations classified as"strong" between unsuccessful kicks were obtained with total distance covered (r=0.51; p=0.06), distance covered at high intensity (r=0.51; p=0.09) and with distance covered in sprints (r=0.56; p=0.06), suggesting that the efficacy of kicks is influenced by the match intensity.

Resumo O objetivo do presente estudo foi quantificar a demanda física, em termos de distância percorrida, e verificar a relação com o desempenho técnico durante partidas simuladas de futsal em atletas da categoria sub-19. Participaram do estudo 16 jogadores de nível estadual. Foram realizadas duas partidas simuladas, sendo a demanda física quantificada pela distância total percorrida, distância percorrida por minuto e distância em diferentes intensidades. Ainda, analisou-se variáveis de desempenho técnico durante as partidas. A distância total percorrida foi, em média, de 3259,97 ± 180,27 m, com média 113,26 ± 6,11 m/min. Aproximadamente 26% da distância total foi percorrida em ações de alta intensidade (i.e., >15 km/h), com decréscimo significativo destas ações no segundo tempo dos jogos (p<0,05). Não foram observadas correlações significativas entre as variáveis de demanda física e as variáveis de desempenho técnico. Contudo, verificou-se correlações positivas classificadas como "fortes" da variável técnica finalização errada por atleta no jogo com a distância total percorrida no jogo (r=0,54; p=0,06), distância percorrida em alta intensidade (r=0,51; p=0,09) e com a distância percorrida em sprints (r=0,56; p=0,06). Este estudo demonstrou que partidas simuladas de futsal, realizadas com atletas da categoria sub-19, apresentam uma elevada demanda física, com valores de distância percorrida por minuto e percorrida em diferentes faixas de intensidade semelhantes aos encontrados em atletas brasileiros profissionais durante jogos oficiais. Não se observou correlações significativas entre o desempenho físico e o desempenho técnico durante as partidas; contudo, foram obtidas correlações classificadas como "fortes" da variável finalização errada com a distância total e com a distância percorrida em alta intensidade, sugerindo que a eficácia das finalizações é influenciada pela intensidade do jogo.

Effect of official judo matches on handgrip strength and perceptual responses.

This study aimed to verify the effect of judo matches on handgrip strength and perceptual responses during an official tournament in medalists and nonmedalists. Thirty-four male judo athletes participated in an official judo tournament. Before the first match and immediately after each match, maximum isometric handgrip strength and rate of perceived exertion overall and in specific areas were assessed. Analysis of variance for repeated measures was used to compare variables before the first match and after each match, and t-test was used to compare medalists and nonmedalists with the level of significance set at 5%. Also, effect size (ES) analysis was used. The results showed decrease in handgrip strength in both hands from the third match (P<0.05). The rate of perceived exertion (RPE) increased from the first match and remained high over the subsequent matches (P<0.001). A very large effect for nonmedalist group (ES=3.44) and large effect for medalist group (ES=1.94) was found in the third match compared to prematch. Forearm and fingers were the body regions most cited by athletes in both groups. We concluded that an official judo competition induced significant drop in handgrip strength from the third match and increased the RPE from first match. Medalists seem to have better recovery after the third match compared to nonmedalists.

Effect of Jump Interval Training on Kinematics of the Lower Limbs and Running Economy.

Ache-Dias, J, Pupo, JD, Dellagrana, RA, Teixeira, AS, Mochizuki, L, and Moro, ARP. Effect of jump interval training on kinematics of the lower limbs and running economy. J Strength Cond Res 32(2): 416-422, 2017-This study analyzed the effects of the addition of jump interval training (JIT) to continuous endurance training (40-minute running at 70% of peak aerobic velocity, 3 times per week for 4 weeks) on kinematic variables and running economy (RE) during submaximal constant-load running. Eighteen recreational runners, randomized into control group (CG) or experimental group (EG) performed the endurance training. In addition, the EG performed the JIT twice per week, which consisted of 4-6 bouts of continuous vertical jumping (30 seconds) with 5-minute intervals. The oxygen consumption (V[Combining Dot Above]O2) during the submaximal test (performed at 9 km·h) was similar before (EG: 38.48 ± 2.75 ml·kg·min; CG: 36.45 ± 2.70 ml·kg·min) and after training (EG: 37.42 ± 2.54 ml·kg·min; CG: 35.81 ± 3.10 ml·kg·min). No effect of training, group, or interaction (p > 0.05) was found for RE. There was no interaction or group effect for the kinematic variables (p > 0.05). Most of the kinematic variables had a training effect for both groups (support time [p ≤ 0.05]; step rate [SR; p ≤ 0.05]; and step length [SL; p ≤ 0.05]). In addition, according to the practical significance analysis (percentage chances of a better/trivial/worse effect), important effects in leg stiffness (73/25/2), vertical stiffness (73/25/2), SR (71/27/2), and SL (64/33/3) were found for the EG. No significant relationship between RE and stiffness were found for EG and CG. In conclusion, the results suggest that JIT induces important changes in the kinematics of the lower limbs of recreational runners, but the changes do not affect RE.

Capacidade de sprints repetidos e níveis de potência muscular em jogadores de futsal das categorias sub-15 e sub-17 / Repeated sprint ability and muscle power levels of the futsal players of U15 and U17 categories / Capacidad de sprints repetidos y niveles de potencia muscular en jugadores de fútbol sala de las categorías cadete y júnior

Resumo O principal objetivo deste estudo foi comparar o desempenho nos saltos verticais e sprints repetidos feitos com mudança de sentido (SRMS) e linha reta (SRLR) entre jogadores de futsal das categorias sub-15 e sub-17. Foram avaliados 15 jogadores do sexo masculino, que fizeram saltos verticais e testes de sprints repetidos em linha reta e mudança de sentido. Não foi encontrada diferença no desempenho dos sprints e no índice de fadiga (p > 0,05) nos SRMS e SRLR, assim como nos saltos verticais (p > 0,05) entre as categorias. Observou-se correlação significativa (p < 0,05) do desempenho nos SRMS e SRLR com os saltos verticais. O desempenho nos sprints e saltos verticais foi similar entre jogadores das categorias. A potência muscular foi relacionada com o desempenho nos sprints.

Abstract The main purpose of the study was to compare the performance of vertical jumps and shuttle (RSS) and straight line (RSL) repeated sprint running between futsal players of U15 and U17 categories. Fifteen male futsal players performed vertical jumps and repeated sprints tests in straight line and change of direction. There were no significant differences of sprint performance and fatigue index (p > 0.05) in the RSS and RSL, as well as vertical jumps (p > 0.05) between categories. Significant correlation (p < 0.05) of sprint performance in both RSS and RSL with vertical jumps performance were observed. Sprints performance and vertical jumps were similar between U15 and U17 categories. The level of muscle power was related to sprint performance.

Resumen El principal objetivo del estudio fue comparar el rendimiento en los saltos verticales y en los sprints repetidos con cambio de dirección (SRCD) y línea recta (SRLR) entre jugadores de fútbol sala de las categorías cadete y júnior. Quince jugadores realizaron los saltos verticales y las pruebas de sprints con cambio de dirección y línea recta. No se encontró ninguna diferencia en el rendimiento de los sprints y el índice de fatiga (p > 0,05) en los SRCD y los SRLR, así como en los saltos verticales entre las categorías. Hubo una correlación significativa (p < 0,05) del rendimiento en los SRCD y SRLR con los saltos verticales. El rendimiento en los sprints y saltos verticales fueron similares entre las categorías. El nivel de potencia muscular se relacionó con el rendimiento en los sprints.

Bilateral asymmetry of knee and ankle isokinetic torque in soccer players u20 category / Assimetria bilateral no torque isocinético do joelho e tornozelo em jogadores de futebol da categoria sub 20

Abstract Bilateral asymmetries and muscle imbalances are associated with increased risk for lower limb injuries and still seem to imply in athletes performance. This study aimed to analyze bilateral asymmetry of soccer players in age category below 20 years old (peak torque and conventional and functional reason in extensor/flexors of knee and inverter/ eversion of ankle) and to compare these variables between defending, midfield and attacker players. The study included 22 athletes in age category below 20, which underwent a five maximal isokinetic testing with repetitions at 180°/s for knee and 120°/s for ankle, both concentric and eccentric actions. T test for dependent data was used to compare values of torque between dominant and non-dominant limbs and one-way ANOVA was used to compare neuromuscular variables between players of different positions, both at p <0.05. No significant differences were observed in any neuromuscular variable (peak torque and functional and conventional ratio) between dominant and non-dominant sides (p> 0.05). It was found that defensive players had eccentric torque values of extensors knee higher than midfield players (p <0.05). Defensive players exhibit greater eccentric torque of knee extensor muscles compared to midfield players. It can be concluded that the analyzed soccer players did not present bilateral asymmetries in flexor/extensor knee muscles neither in inverter/eversion ankle muscles.

Resumo As assimetrias bilaterais e os desequilíbrios musculares estão associados com o risco aumentado para lesões nos membros inferiores e ainda parecem implicar o desempenho dos atletas. Assim, este estudo objetivou analisar a assimetria bilateral de jogadores de futebol da categoria sub 20 (pico de torque e razão convencional e funcional dos extensores/flexores do joelho e inversores/eversores do tornozelo), além de comparar tais variáveis entre jogadores defensores, meias e atacantes. Participaram deste estudo 22 atletas da categoria sub 20, que foram submetidos a um teste isocinético com cinco repetições máximas a 180º/s para o joelho e 120º/s para o tornozelo, ambos com ações concêntricas e excêntricas. Utilizou-se o teste t para dados dependentes para comparar os valores de torque entre os membros dominante e não-dominante e ANOVA one way para comparar as variáveis neuromusculares entre jogadores de diferentes posições, ambos a p < 0,05. Não foram observadas diferenças significativas em nenhuma variável neuromuscular (pico de torque e razão funcional e convencional) entre os lados dominante e não-dominante (p > 0,05). Foi verificado que os jogadores defensores apresentavam valores de torque excêntrico nos extensores do joelho, superiores aos meias (p < 0,05). Os jogadores que atuam na defesa apresentam maior torque excêntrico nos extensores do joelho, quando comparados aos jogadores de meio-campo. Pode-se concluir que os jogadores analisados não apresentaram assimetrias bilaterais nos músculos flexores/extensores do joelho, bem como nos inversores/eversores do tornozelo.

Effects of four weeks of repeated sprint training on physiological indices in futsal players / Efeito de quatro semanas de treinamento de sprints repetidos sobre índices fisiológicos em atletas de futsal

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.

Respuestas fisiológicas y neuromusculares en esprines repetidos con cambio de dirección y en línea recta / Physiological and neuromuscular responses in the shuttle and straight line-repeated sprint running

Introducción: El objetivo de este estudio fue comparar y relacionar el rendimiento en sprint repetidos con cambio de dirección (ERCD) y en línea recta (ERLR), y comparar las respuestas fisiológicas y neuromusculares obtenidas post-ERCD y post-ERLR. Material y métodos : Formaron parte del estudio 14 jugadores de fútbol sala que realizaron sprint (25 m) con cambio de dirección y en línea recta. Se evaluó el rendimiento en los sprint (tiempo medio, mejor tiempo e índice de fatiga) y el countermovement jump (CMJ) antes y después de las 2 pruebas, además de las concentraciones de lactato en sangre (LACPEAK) después de los sprint. Resultados: El tiempo medio (TM) y mejor tiempo (MT) fueron más bajos en los ERLR (p < 0,01), mientras que el índice de fatiga fue más bajo en los ERCD (p = 0,02). Se observaron correlaciones entre TMLR y TMCD (r = 0,79), así como entre MTLR y MTCD (r = 0,69). Se encontraron diferencias en el rendimiento del CMJ entre los valores basales y post-ERLR (p = 0,01), así como con el post-ERCD (p = 0.02). No hubo diferencias entre el rendimiento del CMJ (p = 0,08) y LACPEAK (p = 0,09) entre post-ERLR y post-ERCD. Conclusiones: A pesar de las diferencias entre MT y TM en las 2 pruebas de sprint repetidos, el TM presentó gran correlación, sugiriendo que la capacidad de sprint repetidos es una calidad general y no depende de los cambios de dirección. Además, tanto la demanda glucolítica como la neuromuscular no fueron diferentes entre las 2 pruebas de sprint (AU)

Introduction: The aim of the present study was to compare and analyze the performance in the shuttle (RSS) and straight line (RSL) repeated sprint running and to compare the physiological and neuromuscular responses obtained post-RSL and post-RSS. Material and methods: Fourteen male futsal players performed 25 m sprints in a straight line and with a change of direction. The sprint performances (mean time, best time and fatigue index), countermovement jump (CMJ) performance were evaluated before and after both tests, as well as measuring blood lactate concentrations (LACPEAK) after the sprints. Results: The mean time (MT) and best time (BT) were lower in the RSL (P < 0.01), while the fatigue index was lower in the RSS (P = 0.02). Significant correlations were found between MTRSL and MTRSS (r = 0.79), as well as between BTRSL and BTRSS (r = 0.69). Significant differences in CMJ performance were recorded between baseline and post-RSL (P = 0.01), as well as between baseline and post-RSS (P = 0.02). No significant differences were found between CMJ performance (P = 0.08) and LACPEAK (P = 0.09) and post-RSL and post-RSS. Conclusions: It was concluded that, despite the differences in BT and MT in the two models of repeated sprints, the MT in both tests correlated well, suggesting that repeated sprint ability is a general quality and independent of changing direction. Moreover, both the glycolytic and neuromuscular demand did not differ between the two sprints models (AU)

Indices fisiológicos e neuromusculares determinantes da performance de corredores velocistas e meio-fundistas / Physiological and neuromuscular indices to determine performance of sprinters and middle distance runners / Índices fisiológicos y neuromusculares determinantes del rendimiento de corredores velocistas y de medio fondo

O objetivo deste estudo foi comparar índices fisiológicos e neuromusculares de corredores e predizer a performance dos mesmos. Treze velocistas (VEL) e 11 meio-fundistas (MF) realizaram as seguintes avaliações: 1) performance nos 400 (P400) e 800 m (P800) e pico de lactato (LACmax); 2) determinação do VO2max, velocidade do VO2max (vVO2max) e do LAn (vLAn); 3) tempo limite; 4) máximo déficit acumulado de oxigênio (MAOD) e 5) counter movement jump (CMJ). Os VEL apresentaram maior MAOD, tempo de pico de lactato, altura e velocidade no CMJ. O VO 2max, vVO2max e vLAn foram maiores nos MF. Conclui-se que os VEL possuem maior capacidade anaeróbia e que os MF apresentam maior aptidão aeróbia. A P400 foi determinada pela associação do LACmax, VO2max e CMJ, enquanto que o LACmax e vVO2max explicaram a P800.

The aim of this study was to compare physiological and neuromuscular indices of runners and predict their performance. Thirteen sprinters (SP) and 11 middle distance runners (MD) performed the following tests: 1) performance in 400 (P400) and 800 m (P800) and lactate peak (LACmax); 2) determination of VO2max, velocity at VO2max-vVO2max and velocity at LAn-vLAn; 3) time limit; 4) maximum accumulated oxygen deficit-MAOD; and 5) counter movement jump (CMJ). The SP showed higher values of MAOD, time of lactate peak, height and velocity at CMJ. VO2max, vVO2max and vLAn were higher for MD. It is concluded that SPR develop higher anaerobic capacity, and MD have a higher fitness aerobic level. The P400 was determined by the association of LACmax, VO2max and CMJ, while LACmax and vVO2max explained the P800.

El objetivo de este estudio fue comparar índices fisiológicos y neuromusculares de corredores y predecir el rendimiento de los mismos. Trece velocistas (VEL) y 11 corredores de medio fondo (MF) hicieron las siguientes evaluaciones: 1) performance en los 400m (P400) y 800 m (P800) y pico de lactato (LACmax); 2) determinación del VO2max, velocidad del VO2max (vVO2max) y del LAn (vLAn); 3) tiempo límite; 4) máximo déficit acumulado de oxígeno (MAOD); 5) counter movement jump (CMJ). Los VEL presentaron mayor MAOD, tiempo de pico de lactato, altura y velocidad en CMJ. El VO2max, vVO2max y vLAn fueron mayores para los MF. Se concluye que los VEL desarrollaran una mayor capacidad anaeróbica, y los MF presentaron un mejor condicionamiento aeróbico. El P400 se determinó por la asociación de LACmax, VO2max e CMJ, mientras el LACmax y vVO2max explicó el P800.

Parâmetros cinéticos determinantes do desempenho nos saltos verticais / Kinetic parameters as determinants of vertical jump performance

Este estudo objetivou identificar parâmetros de força e velocidade relacionados com o desempenho nos saltos verticais (SV) Counter Movement Jump (CMJ) e Squat Jump (SJ); comparar estes parâmetros entre corredores velocistas e voleibolistas. Participaram 24 atletas do sexo masculino (12 velocistas de nível estadual/nacional e 12 voleibolistas de nível nacional). Os atletas realizaram os SV CMJ e SJ sobre uma plataforma de força, sendo analisadas variáveis de desempenho (altura do salto e potência), pico de velocidade (PV), força máxima (Fmax) absoluta e relativa, taxa de desenvolvimento de força (TDF) e tempo para atingir a força máxima (TFmax). No CMJ, a altura correlacionou-se com o PV (r=0,97) e com a Fmax normalizada (r=0,47), enquanto que a potência relacionou-se com todas as variáveis, exceto com a Fmax absoluta (r=0,12). No SJ, o PV e a Fmax normalizada correlacionaram-se com a altura obtida (r=0,95; r=0,51, respectivamente) e com a potência (r=0,80; r=0,87, respectivamente). Além disso, a TFmax também correlacionou-se com a potência (r=-0,49). Os velocistas apresentaram valores superiores nas variáveis de desempenho do salto (altura e potência), na Fmax e no PV, tanto no SJ como CMJ. Conclui-se que o pico de velocidade e a força máxima normalizada foram os principais determinantes da altura e da potência obtida em ambos os SV. Contudo, a força explosiva (TDF e TFmax) também mostrou-se importante na produção de potência nos SV. Por fim, os velocistas apresentaram melhor desempenho nos SV em relação às voleibolistas.

This study evaluated force and velocity parameters of vertical jump performance in countermovement jump (CMJ) and squat jump (SJ) and compared results for sprint runners and volleyball players. Twenty-four male athletes (12 regional/national-level sprint runners and 12 national-level volleyball players) performed CMJ and SJ on a force platform. The following variables were analyzed: jump performance (jump height and power), peak velocity (PV), absolute and relative maximum force (MF), rate of force development (RFD,) and time to reach maximum force (TMF). In CMJ, jump height was correlated with PV (r=0.97) and normalized MF (r=0.47), whereas jump power was significantly correlated with all variables, except MF (r=0.12). In SJ, PV and normalized MF were significantly correlated with jump height (r=0.95 and r=0.51) and power (r=0.80 and r=0.87). In addition, TMF was inversely correlated with power (r=-0.49). Runners had higher performance variables (height and power), normalized MF and PV than volleyball players in both CMJ and SJ. Velocity and maximum force were the main determinants of height and power in the two types of vertical jumps. However, explosive force (RFD and TMF) was also important for power production in vertical jumps. Runners had a better vertical jump performance than volleyball players.

Índices fisiológicos e neuromusculares relacionados à performance nas provas de 800 m e 1500 m rasos / Neuromuscular and physiological indices associated with 800- and 1500-m running performance

O objetivo deste estudo foi determinar e correlacionar os índices fisiológicos e neuromusculares com a performance de corredores treinados nas distâncias de 800 m e 1500 m. Onze atletas realizaram os seguintes testes: 1) determinação das performances nos 800 m e 1500 m; 2) determinação do consumo máximo de oxigênio (VO2max), velocidade correspondente ao VO2max (vVO2max) e velocidade correspondente ao onset of blood lactate accumulation; 3) saltos verticais (Counter Movement Jump - CMJ e Continuous Jump - CJ); 4) determinação do tempo de exaustão (Tlim) e 5) testes submáximos para determinação da economia de corrida e teste supra-máximo para cálculo do máximo déficit acumulado de oxigênio. Houve correlação significante da vVO2max e do Tlim com as duas provas. O CJ se correlacionou somente com os 800 m. Conclui-se que a potência aeróbia é a principal determinante da performance nas duas distâncias, destacando-se que os aspectos neuromusculares influenciam os 800 m.

The purpose of this study was to determine and correlate the neuromuscular and physiological indices with the performance of trained runners in distances of 800 m and 1500 m. Eleven athletes were evaluated in the following tests: 1) simulation of performances in 800 m and 1500 m; 2) determination of maximum oxygen consumption-VO2max; velocity at VO2max-vVO2max and of velocity at onset of blood lactate accumulation; 3) vertical jumps (Counter Movement Jump and Continuous Jump); 4) determination of time to exhaustion-Tlim; and 5) submaximal tests for identification of running economy, followed by a supramaximal test for determination of maximum accumulated oxygen deficit. vVO2max and Tlim were correlated with both distances. The CJ was correlated only to 800m. It is concluded that aerobic power is the main determinant of performance for the two distances, emphasizing that neuromuscular aspects influence the 800 m.

O uso do centro articular do quadril e do centro de gravidade da cabeça como referência na estimativa de parâmetros cinemáticos da performance em corridas de velocidade / The use of the hip joint center and head gravity center as a reference to estimate the performance kinematics parameters in speed races

O objetivo deste estudo foi comparar a velocidade e o deslocamento do centro de gravidade global (CGG) com as centro de gravidade da cabeça (CGC) e do centro articular do quadril (CAQ), durante um passo em corridas de velocidade. A partir disso, determinar se tais pontos podem ser utilizados como indicadores de parâmetros da performance nos estudos envolvendo a cinemática das corridas. Participaram deste estudo 8 sujeitos do sexo masculino, com idade média de 12,5 ± 0,66 anos e estatura média de 163,00 ± 5,40 cm. Realizou-se uma análise cinemática da corrida, utilizando-se o método de videografia tridimensional, com quatro câmeras de vídeo do sistema de análise do movimento Peak Motus, operando na freqüência de 180 Hz. As variáveis analisadas foram deslocamento, velocidade média e velocidade instantânea horizontal do CGG, CGC e CAQ referentes a um passo. Os resultados encontrados mostraram não haver diferenças significativas na velocidade média e amplitude de deslocamento entre os três pontos analisados. Em relação à velocidade instantânea analisada em todo passo, não verificou-se diferenças significativas, porém, as variações na curva de velocidade do CAQ não ocorreram na mesma escala de tempo quando comparado com os demais pontos. Concluiu-se assim que, tanto o CGG, assim como o CGC e CAQ, podem ser utilizados para descrever parâmetros cinemáticos da corrida, quando o objetivo da análise referir-se a deslocamentos e velocidade média de um passo. Em relação à descrição da velocidade instantânea do atleta nas diferentes fases do passo, o uso do CGG e CGC parecem ser os mais adequados a serem utilizados.

The objective of this study was to compare the speed and the displacement of the global gravity center (CGG) with the head gravity center (CGC) and the hip joint center (CAQ) during a step in speed races. After, to determine if these points could be used as indicators of the performance parameters in the studies involving the kinematics of the speed races. To accomplish this study, eight male subjects participated. They were around 12.5 ± 0.66 years old and their average height was 163.00 ± 5.40 cm. A kinematic analysis of the running was carried out by using the method of three-dimensional videography, with four video cameras of the Peak Motus system operating in the frequency of 180 Hz. The analyzed variables were displacement, average speed and horizontal instantaneous speed of CGG, CGC and CAQ that refer to one step. The results showed that there are not significant statistical differences in both the average speed and the displacement amplitude among the three analyzed points. Concerning the instantaneous speed analyzed in the whole step, no significant differences were found. However, the variations in the CAQ speed curve did not occur in the same scale of time when compared with the other points. Thus, one concluded that the CGG, the CGC and the CAQ can be used to describe kinematics parameters of the running when the aim of analysis refers to displacement and average speed of one step. Concerning the description of instantaneous speed of athletes in different step phases, the use of CGG and CGC seems to be the most appropriate.

Evaluación de la composición corporal y la flexibilidad en futbolistas profesionales en diferentes etapas del ciclo de entrenamiento / The corporal composition and flexibility evaluation of the professional soccer players in the different stages of the training cycle

La cuantificación de los componentes corporales es considerada una importante herramienta para la evaluación, diagnóstico, prescripciones y control del entrenamiento en sus diferentes fases, visto que estas variables guardan estrecha relación con el rendimiento del atleta. En este sentido, este estudio tiene como objetivo comparar variables de la composición corporal (porcentaje de grasa (%G), porcentaje de masa muscular (%MM), masa corporal total (MC) y flexibilidad de futbolistas en diferentes etapas del ciclo de entrenamiento: en el comienzo del periodo preparatorio (pretemporada) y en el comienzo del periodo competitivo (4 semanas después). Participaron de este estudio 20 jugadores de fútbol profesionales, con edad media de 23,47± 3,60 años y estatura media de 181,58 ± 5,45 cm. Fueron realizadas medidas antropométricas de pliegues cutáneos para estimar %G y %MM, además de medidas de MC y test con el banco de Wells para evaluar la flexibilidad, antes y después del periodo de entrenamiento realizado por los jugadores. El entrenamiento fue específico del fútbol y establecido por el preparador físico del equipo. Fue aplicado un test t pareado para comparar los valores pre y pos. Fue observado después del entrenamiento realizado una reducción significativa (p<0,05) en los niveles de MC y %G, siendo que los valores pasaron de 77,03 ± 6,48 kg para 75,91 ± 6,03 kg y de 11,21 ± 2,88% para 10,32 ±1,69%, respectivamente. Los niveles de flexibilidad aumentaran significantemente post-entrenamiento (32,25 para 33,24 cm) y no hubieron alteraciones en relación al %MM. Se concluye así que 4 semanas de entrenamiento inducen cambios en la morfología y flexibilidad de los futbolistas, probablemente asociado a la mejoría en las capacidades funcionales y técnica de los deportistas (AU)

The body components quantification is considered important tool for the evaluation, diagnosis, prescriptions and control of the training in different phases, because these variables have relationship with the athlete’s performance. In this sense, this study aims to compare body composition variables (percentage of fat mass, percentage of muscular mass and total body mass) and flexibility of the soccer players in different stages of cycle training: in the beginning of the preparatory period (pre-season) and in beginning of the competitive period (4 weeks later). Twenty professional soccer players with average age of 23,47 ± 3,60 years old and high average of 181,5 ± 5,45 cm took part in this study. The level of fat mass and muscular mass was estimated by skinfolds and body mass was measured using an electronic scale. The flexibility was evaluated by test of sit and reach of Wells. The training was specific for soccer and established for the physical coach of the team. A “t” test was applaied to compare pre and post results. It was observed after the training a significant reduction (p<0,05) in the levels of total body mass and fat body mass, in the which, the values passed from 77,03 ± 6,48 kg to 75,91 ± 6,03 kg and of 11,21 ± 2,88% to 10,32 ± 1,69%, respectively. The levels of flexibility increased significantly after the training period (32,25 to 33,24 cm) and there were not changes in relation to the muscular mass percent. Based on the data we can infer that 4 weeks-training changes the athletes’ morphology and flexibility, which can suggest an increase in the physical condition and technical capability (AU)