Development and Pilot Testing of a New Electromyography Device

Abstract

In recent years, no other aspect of muscle loading has been more investigated in the literature than eccentric movement. However, issues involving muscle responses from eccentric training are not fully understood. Thus, the objective of this study is to develop and test a new electromyography device (EMG Lavita) capable of assisting researchers and clinicians in understanding the muscular responses from eccentric contraction. An electronic circuit composed by an INA118P, a 30 to 150 Hz bandpass filter and a rectifier was developed. The analog signal is converted into a digital signal using a 10-bit A/D converter that is part of the Atmega328p microcontroller which sends the data through a serial communication to a supervisory system which them processes and shows the data in graphic way. A pilot test was performed and simultaneously recorded the EMG signals from the brachial biceps muscle using two different electromyography devices, a Commercial EMG and EMG Lavita. For this test one researcher performed 5 data collections consisting of 10 repetitions of the elbow flexion movement with one-minute interval between them. After the data collection, a statistical test was performed to verify the Pearson correlation coefficient to compare the RMS values of the devices. The EMG Lavita behaved similarly to commercial EMG, presenting (r = 0.86) which shows a good to excellent correlation. The EMG Lavita device showed strong correlation with the commercially used device.