Análise eletromiográfica de músculos do tronco e percepção subjetiva de esforço no exercício prancha ventral até a exaustão com diferentes equipamentos instáveis

Abstract

There has been an increasing popularity of core training in recent years, and like any other form of training, exercise selection, overload and progression must be continuously adjusted to improve the training effect. The objective of this study was to analyze the duration, effort perceivied and arbitrary unit and electromyographic activity of the Rectus Abdomen (RA), External Oblique Abdomen (OE), Internal Oblique Abdomen (OI), Erector da Espinha (EE) and Multifido (MU) in the ventral plank exercise on the ground (PV-SO), from the comparison of said activity with different unstable equipment [Bosu (PV-BS, gym ball (PV-BG), Peanut ball (PV-PB) and TRX® (PV-TX)]. Electromyography was analyzed in different stages: beginning (STEP A: five and 10 seconds), middle (STEP B: 50% signal) and finale (STEP C: 100% signal). The sample consisted of 15 male volunteers, physically active, with an average age of 23 ± 2.00 years, body mass 74.13 ± 4.05 kg, height 176.06 ± 4.22 cm, percentage of fat 12,06 ± 3.04%. Minimum of one year of resistance training practice and without neuromuscular disorder. The data collection was performed using simple differential surface electrodes, with a 20-fold gain, and recorded using a computerized electromyograph (EMG System do Brazil 830C). The electromyographic signal was analyzed in the temporal domain (Root Mean Square - RMS) and in the spectral domain through the median frequency. Shapiro Wilk test was used to assess the normality of the data and, subsequently, the two-way ANOVA test. The electromyographic activity of core muscles in the PV-TX exercise was significantly higher (RMS) and lower (Fmed) compared to the other stabilization exercises until exhaustion, in addition, the EMG activity of the flexor and extensor group was greater in the exercise PV-TX. The EMG activity pattern of core muscles showed similarity for all the exercises analyzed, in which a predominantly increase (RMS) and linear reduction (Fmed) was observed. The duration and Arbitrary Units of the PV-TX exercise were shorter compared to other conditions, however the PSE did not show any significant differences. These results support that there is a difference in the choice of progression from core stabilization exercises to exhaustion, therefore, the selection should be in initial stage with this exercises: PV-SO, PV-BS, PV-BG, PV-PB; and avanced stages with PV-TX.