Unlike the discrete waveform from an electrocardiogram, the electromyogram waveform is irregular. why do you suppose this is? answer

The electromyogram waveform is irregular because, its recording is that of a muscle that contracts all the time. The waveform of electrocardiogram is discreet because it records muscles that are contracting asynchronously. Thus, the waveform of electromyogram is irregular simply because it recorded the activation of many muscle fibers.