Análise eletrofisiográfica e histomorfológica do músculo tibial anterior de ratos submetidos a treinamento aeróbico com natação

Fitness & performance journal, ISSN 1519-9088, Nº. 1, 2009, pags. 49-55
Source: OAI

ABSTRACT Introdução: O objetivo deste estudo foi avaliar a força contrátil, a resistência à fadiga e a integridade fibrilar de um músculo fundamentalmente constituído de fibras anaeróbicas (tibial anterior) de ratos submetidos a treinamento aeróbico com natação. Materiais e Métodos: 21 ratos machos Wistar (353±32g) foram divididos em três grupos experimentais (n=7): grupo controle (GC), grupo treinado com carga (5% da massa corporal) em meio líquido (GTC) e grupo treinado sem carga em meio líquido (GT). O protocolo de treinamento de natação teve 1h diária, por cinco dias consecutivos, durante cinco semanas. Após 72h do período experimental, obteve-se o registro eletrofisiográfico do músculo tibial anterior: a) tensão máxima gerada pelo músculo (g); b) tempo (s) que o músculo manteve-se contraído até 50% da tensão máxima; e c) a área sob a curva tetânica (cm2) até 50% da tensão máxima, durante cada contração tetânica induzida. Além disso, foi feita análise histológica desse músculo. Para análise dos dados foi aplicado ANOVA, seguida pelo teste Tukey-Kramer. Resultados: Os resultados demonstraram que o GT apresentou valores significativamente superiores (p<0,05) em relação os demais grupos para a variável tempo de contração a 50% da tensão máxima. Além disso, a análise histológica não evidenciou qualquer tipo de dano muscular. Discussão: concluiu-se que o protocolo de treinamento utilizado sem o implemento de peso promove melhores adaptações musculares, aumentando a capacidade do músculo tibial anterior em resistir à fadiga.

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