Taxa de desenvolvimento de força em diferentes velocidades de contrações musculares
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Data
2009-12-01
Autores
Corvino, Rogério Bulhões [UNESP]
Caputo, Fabrizio [UNESP]
Oliveira, Anderson Castelo de [UNESP]
Greco, Camila Coelho [UNESP]
Denadai, Benedito Sérgio [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Sociedade Brasileira de Medicina do Exercício e do Esporte
Resumo
O objetivo deste estudo foi comparar a taxa de desenvolvimento de força (TDF) nas contrações isométrica e isocinética concêntrica a 60°.s-1 e 180°.s-1. Quatorze indivíduos do gênero masculino (idade = 23,1 ± 2,8 anos; estatura = 174 ± 31,3cm; massa corporal = 81 ± 12kg) realizaram inicialmente uma familiarização ao equipamento isocinético. Posteriormente, os indivíduos realizaram em ordem randômica cinco contrações isocinéticas máximas para os extensores do joelho a 60°.s-1 e 180°.s-1 para determinar o torque máximo concêntrico (TMC) e duas contrações isométricas máximas de 3s para determinar o torque máximo isométrico (TMI). O TMI (301,4 ± 56,0N.m) foi maior do que o TMC a 60°.s-1 (239,8 ± 42,2N.m) e 180°.s-1 (175,0 ± 32,5 N.m). O TMC a 60°.s-1 foi maior do que o TMC a 180°.s-1. Para os intervalos de 0-30ms e 0-50ms, a TDF na condição isométrica (1.196,6 ± 464,6 e 1.326,5 ± 514,2N.m.s-1, respectivamente) foi similar à TDF a 60°.s-1 (1.035,4 ± 446,2 e 1.134,3 ± 448,4N.m.s-1) e maior do que a 180°.s-1 (656,7 ± 246,6 e 475,2 ± 197,9N.m.s-1), sendo ainda que a TDF na contração concêntrica a 180°.s-1 foi menor do que a 60°.s-1. No intervalo de 0-100ms, a TDF da contração isométrica (1.248,8 ± 417,4N.m.s-1) foi maior que a obtida na contração isocinética rápida (909,2 ± 283,4N.m.s-1). A TDF obtida na contração isocinética lenta (1.005,4 ± 247,7N.m.s-1) foi similar à obtida na contração isométrica e na concêntrica isocinética rápida. No intervalo 0-150ms, a TDF isométrica (1.084,2 ± 332,1N.m.s-1) foi maior do que as concêntricas (60°.s-1 e 180°.s-1) (834,8 ± 184,2 e 767,6 ± 201,8N.m.s-1, respectivamente), não existindo diferenças entre estas duas últimas. Conclui-se que a TDF é dependente do tipo e da velocidade de contração, suportando a hipótese de que maiores velocidades de contração acarretam maior inibição do drive neural no início do movimento.
The objective of this study was to compare the maximal rate of force development (RFD) at maximal isometric and isokinetic concentric contractions at 60°.s-1 and 180°.s-1. Fourteen active males (age = 23.1 ± 2.8 years; height = 174 ± 31.3 cm and body mass = 81 ± 12 kg) volunteered to participate in this study. During the first visit, subjects performed a familiarization to the isokinetic equipment. During the second visit, subjects performed in random order 5 maximal isokinetic concentric contractions for knee extensors at each angular velocity (60 and 180°.s-1) to determine maximal concentric torque (MCT) and 2 maximal isometric contractions of 3 s to determine maximal isometric torque (MIT). The MIT (301.4 ± 56.0 N.m) was higher than MCT at 60°.s-1 (239.8 ± 42.2 N.m) and 180°.s-1 (175.0 ± 32.5 N.m). The MCT at 60°.s-1 was higher than MCT at 180°.s-1. At intervals of 0-30ms and 0-50ms, the RFD at isometric contraction (1196.6 ± 464.6 and 1326.5 ± 514.2 N.m.s-1, respectively) was similar to that obtained during concentric contraction at 60°.s-1 (1035.4 ± 446.2 N.m.s-1 and 1134.3 ± 448.4 N.m.s-1, respectively) and higher than that obtained during concentric contraction at 180°.s-1 (656.7 ± 246.6 N.m.s-1 and 475,2±197,9 N.m.s-1, respectively). For the interval of 0-100ms, RFD at isometric contraction (1248.7 ± 417.4 N.m.s-1) was higher than that obtained during concentric contractions at 180°.s-1 (909.2 ± 283.4 N.m.s-1), and similar to concentric contractions at 60°.s-1 (1005.4 ± 247.7 N.m.s-1). However, for the interval of 0-150ms, RFD at isometric contraction (1084.2 ± 332.1 N.m.s-1) was higher than at 60°.s-1 (834.8 ± 184.2 N.m.s-1) and 180°.s-1 (767.6 ± 767.6 N.m.s-1). It can be concluded that RFD is dependant on the contraction type and velocity, supporting the hypothesis that higher speed of contraction generates higher neural drive inhibition at the beginning of the movement.
The objective of this study was to compare the maximal rate of force development (RFD) at maximal isometric and isokinetic concentric contractions at 60°.s-1 and 180°.s-1. Fourteen active males (age = 23.1 ± 2.8 years; height = 174 ± 31.3 cm and body mass = 81 ± 12 kg) volunteered to participate in this study. During the first visit, subjects performed a familiarization to the isokinetic equipment. During the second visit, subjects performed in random order 5 maximal isokinetic concentric contractions for knee extensors at each angular velocity (60 and 180°.s-1) to determine maximal concentric torque (MCT) and 2 maximal isometric contractions of 3 s to determine maximal isometric torque (MIT). The MIT (301.4 ± 56.0 N.m) was higher than MCT at 60°.s-1 (239.8 ± 42.2 N.m) and 180°.s-1 (175.0 ± 32.5 N.m). The MCT at 60°.s-1 was higher than MCT at 180°.s-1. At intervals of 0-30ms and 0-50ms, the RFD at isometric contraction (1196.6 ± 464.6 and 1326.5 ± 514.2 N.m.s-1, respectively) was similar to that obtained during concentric contraction at 60°.s-1 (1035.4 ± 446.2 N.m.s-1 and 1134.3 ± 448.4 N.m.s-1, respectively) and higher than that obtained during concentric contraction at 180°.s-1 (656.7 ± 246.6 N.m.s-1 and 475,2±197,9 N.m.s-1, respectively). For the interval of 0-100ms, RFD at isometric contraction (1248.7 ± 417.4 N.m.s-1) was higher than that obtained during concentric contractions at 180°.s-1 (909.2 ± 283.4 N.m.s-1), and similar to concentric contractions at 60°.s-1 (1005.4 ± 247.7 N.m.s-1). However, for the interval of 0-150ms, RFD at isometric contraction (1084.2 ± 332.1 N.m.s-1) was higher than at 60°.s-1 (834.8 ± 184.2 N.m.s-1) and 180°.s-1 (767.6 ± 767.6 N.m.s-1). It can be concluded that RFD is dependant on the contraction type and velocity, supporting the hypothesis that higher speed of contraction generates higher neural drive inhibition at the beginning of the movement.
Descrição
Palavras-chave
contração concêntrica, velocidade angular, isocinética, concentric contraction, angular speed, isokinetics
Como citar
Revista Brasileira de Medicina do Esporte. Sociedade Brasileira de Medicina do Exercício e do Esporte, v. 15, n. 6, p. 428-431, 2009.