Effect of Electrode Position on EMG Recording in Pectoralis Major

Despite the relatively long history of electromyography (EMG) application in a wide variety of disciplines, there are still discrepancies on a preferred position of EMG electrodes. The aim of this study was to determine an optimal position of bipolar surface electrodes for muscle pectoralis major. The recording was done during an isometric (static) effort of pressing the barbell from a lying position. The muscle activity was compared in 9 cases (3 positions of electrodes setting for 3 muscle compartments), recorded at a 1.6 s interval. The highest averaged value of integrated EMG for external, central and medial placement of electrodes, independent from the muscle (clavicularis, sternocostalis and abdominalis), was observed in the latter case of electrode positioning.