Mechanical Vibration Increases EMG Activity But Does Not Affect Strength Resistance Performance

• Published in: Journal of exercise physiology online Vol. 22; no. 4; p. 120
• Main Authors: Costa, Victor, Silva, Fabio F. da, Lima, Renan M. de, Mezencio, Bruno, Ferreira, Jacielle C
• Format: Journal Article
• Language: English
• Published: Duluth American Society of Exercise Physiologists 01.08.2019
• Subjects: Fatigue; Time
• ISSN: 1097-9751; 1097-9751

Costa V, Da Silva FF, De Lima RM, Mezencio B, Ferreira JC. Mechanical Vibration Increases EMG Activity But Does Not Affect Strength Resistance Performance. JEPonline 2019;22(4):120-129. The aim of this study was to verify if the mechanical vibration in the exercise of isometric push-up affects the electrical activity of muscles of the upper limbs and the time until the exhaustion. The subjects were 13 experienced strength-training volunteers (25.52 [+ or -] 4.44 yrs). The push-up exercise with vibration of 20 Hz ([V.sub.20]) was accomplished until the exhaustion in one day and on another day without vibration ([V.sub.00]). The electromyographic activity (EMG) of the triceps brachii (TRB) and pectoralis (PT) was measured. There was no difference in the exercise duration between [V.sub.20] and [V.sub.00] (P = 0.954), but in the analysis of the complete signal, the Root Mean Square (RMS) of the TRB and PT was higher in [V.sub.20] compared to [V.sub.00] (P = 0.015, P = 0.018, respectively) and the Median Frequency ([F.sub.MA]) of the EMG was not different between the situations. The partial analysis of the EMG signal showed that in both muscles RMS was bigger in the 10 last sec (10f) and the [F.sub.MA] significantly lower in 10f compared to initial 10 sec. The findings indicate that the frequency vibration of 20 Hz increased the electrical activity of the upper limb muscles, but did not change the performance of strength resistance. Key Words: Electromyography, Neuromuscular efficiency, Upper limbs, Vibration plate