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ABSTRACT We aimed to assess upper and lower limbs explosive strength, and its correlation with biceps brachii (BB) and vastus lateralis (VL) architecture. Absolute and maximum torque normalized rate of torque development (RTD) were measured from isometric elbow flexion (EF) and knee extension (KE). BB and VL architectures were assessed by ultrasound. Absolute RTD of KE was higher (129-272%), although normalized RTD was higher in EF (80-21%). The absolute RTD was correlated to muscle thickness only in the BB (r=.39-46). No relationship was found between muscle architecture and normalized RTD. In conclusion, the higher RTD from KE seems to be due to their greater strength. Only the muscle architecture could not explain the differences found in the RTD.
RESUMO Nosso objetivo foi avaliar a força explosiva de membros superiores e inferiores e a sua correlação com a arquitetura do bíceps braquial (BB) e vasto lateral (VL). A taxa de desenvolvimento de torque (TDT) absoluta e normalizada pela força máxima foi medida na flexão de cotovelo (FC) e extensão de joelho (EJ). A arquitetura do BB e do VL foi avaliada por ultrassonografia. A TDT absoluta de EJ foi maior (129-272%), mas a TDT normalizada foi maior na FC (80-21%). A TDT absoluta foi correlacionada com a espessura do BB (r=.39-46). A TDT normalizada não foi correlacionada à arquitetura muscular. Concluindo, a TDT superior da EJ parece causada pela maior força máxima. Apenas a arquitetura muscular não parece explicar a diferença na TDT.
RESUMEN Nuestro objetivo era evaluar la fuerza explosiva de los miembros superiores y inferiores y su correlación con la arquitectura del bíceps braquial (BB) y vasto lateral (VL). Se medio la tasa de desarrollo de torque (TDT) absoluta y normalizada por la fuerza máxima in la flexión de codo (FC) e extensión de rodilla (ER). La arquitectura del BB y VL fue evaluada por ultrasonido. La TDT absoluta de ER fue mayor (129-272%), pero la TDT normalizada fue mayor en la FC (80-21%). La TDT absoluta se correlacionó con el grosor del BB (r=.39-46). La TDT normalizada no se correlacionó con la arquitectura. En conclusión, la TDT superior del ER parece estar causado por la mayor fuerza máxima. La arquitectura muscular sola no parece explicar la diferencia en la TDT.
RESUMEN
Objective To study the effect of vibration training with adjusted frequency on changes in explosive force of lower limbs, balance and muscle function around ankle joints of patients with functional ankle instability (FAI), so as to provide an empirical basis for rehabilitation training of FAI patients in clinic. Methods Twenty-six FAI patients were randomly divided into the experimental group (n=14) and the control group (n=12). The experimental group received 8-week rehabilitation training with vibration intervention, while the control group only received 8-week rehabilitation training. Changes in maximum power, average power, maximum speed and average speed of the injured limb during vertical jump with single leg, changes in distances during long jump, changes in time during one-leg standing with eyes open and closed，changes in contract time (tc), relax time (tr) and displacement (Dm) of medial gastrocnemius (GM), lateral gastrocnemius (GL) and tibialis anterior (TA) muscles before and after training were measured and compared. Results In the experimental group, the maximum power and maximum speed of the injured limb during vertical jump with single leg, the distance during long jump with single leg and the time during one-leg standing with open and closed eyes were significantly improved, and the increase was higher than that of the control group. The increase of tc of all muscles in the experimental group was smaller than that of the control group, but tr and Dm did not show any regularity. Conclusions Vibration training with adjusted frequency can effectively improve the explosive force and balance ability of lower limbs of FAI patients, and promote the tc shortening of GL, GM and TA muscles, but whether vibration training with adjusted frequency can reduce muscle tension and promote muscle relaxation is still not clear.
RESUMEN
O objetivo deste trabalho foi identificar diferenças existentes entre os níveis de maturação na força explosiva. Amostra de 150 meninos futebolistas, entre 14 e 17 anos. Para o estágio de maturação foi usado o método de Tanner e para a força explosiva de membros inferiores foram usados os testes de impulsão vertical. A estatística envolveu medidas descritivas e para verificar a diferença entre as médias nos estágios maturacionais foram usados os testes não paramétricos de Mann-Whitney U e Kruskal-Wallis. Em ambas as categorias, infantil e juvenil, não ocorreram diferenças significativas nos níveis de força explosiva entre os estágios maturacionais. Isso sugere que os achados do presente estudo podem ser explicados pelo reflexo do treinamento ou das práticas de seleção para o esporte. Contudo, mais pesquisas devem ser conduzidas sobre essa temática.
The objective was to identify differences among maturity levels in explosive force. Sample of n = 150 boys footballers, aged between 14-17 years. For the maturation stage method was used to Tanner and the strength of lower limbs was used vertical jump tests. The descriptive statistical measures involved and to investigate differences between means in maturational stages was used the nonparametric Mann-Whitney U and Kruskal-Wallis. In both categories, child and youth no significant differences in the levels of explosive force between maturational stages. Suggesting that the findings of this study can be explained by the reflection of training or selection practices for the sport, but more research should be conducted on this topic.
El objetivo fue identificar las diferencias entre los niveles de madurez en la fuerza explosiva. Muestra de n = 150 niños futbolistas, de edades comprendidas entre 14-17 años. Para el método de etapa de maduración se utilizó para Tanner y la fuerza de los miembros inferiores se utilizó pruebas de salto vertical. Las medidas estadísticas descriptivas involucrados y para investigar las diferencias entre las medias de las etapas de maduración se utilizó la prueba no paramétrica de Mann-Whitney U y Kruskal-Wallis. En ambas categorías, los niños y los jóvenes no existen diferencias significativas en los niveles de fuerza explosiva entre las etapas de maduración. Lo que sugiere que los resultados de este estudio pueden ser.