Respostas neuromusculares agudas a estimulação vibratória local no exercício de flexão de cotovelo em banco scott

Abstract

The deleterious effects on health-related vibration in the field of physical medicine and occupational therapy have been previously reported. In sports these rules arent existents, although in several sports athletes undergo considerable vibratory loads. In recent years, the significance of the addition of mechanical vibration has gained account as a new training resource due to the great interest in improving the performance of strength and power. The aim of this study was evaluate the acuteeffects of the isometric strength training with addition of vibrations about the neuromuscular responses. Twenty detraining male volunteers were submitted to 4 (four) treatments to which the exercise was the elbow flexion in "Scott" bench. The experiments were: (A) isometric training without vibration (Control); (B) isometric training with sinusoidal vibration (20Hz; 3mm), (C) isometric training with random vibration (20±3Hz, 3mm), (D) isometric training with the combination of sinusoidaland random vibrations (20Hz; 2mm and 20±3Hz; 3mm). The volunteers performed in each treatment 5 series of maximal isometric contractions with duration of 10s spaced by 5 minutes recovery. During the treatments were measured the maximal strength (Fmax), mean strength (Fmed), peak of isometric strength (PForça), rate of force development at intervals of 50ms and 100ms (TPF50 and TPF100), Fatigue index (IF), electromyographycal activity of the biceps and triceps muscles(RMSemgbíceps and RMSemgtríceps), maximal (apico) and mean (arms) acceleration. The addition of local vibrations to the isometric training increased significantly to Fmax, PForça, Fmed and TPF50. For the TPF100 was shown a significant increase in the sinusoidal, random and combined treatments compared to control treatment.Although the random treatment has presented higher mean values compared to control treatment, the increase was not significant. The addition of local vibrations produced a significant reduction of performance (IF) for the sinusoidal and combined treatments compared to control treatment. In spite of the mean reduction of performance shown of the random treatment compared the group control, the differences were not significant. They were not shown significant alterations betweenthe treatment for the electromyographycal activity of the muscles biceps and tríceps brachial (RMSemgbíceps and RMSemgtriceps). From the results was conclude that the addition of vibrations through the sinusoidal, random and combined treatments affects the performance of maximal and explosive strength intervals with complete recovery in untrained without differences among themselves. The treatment withaddition of vibrations sinusoidal and combined a decrease of greater performance than the traditional isometric training. With the addition of the random vibrations to the isometric training, there was not a decreased of performance compared to training with or without addition of vibrations. The electromyographycal activity of the muscles agonist and antagonist in all of the treatments in the elbow flexion exercise was similar.