Fig. 2From: Age-specific differences in the time-frequency representation of surface electromyographic data recorded during a submaximal cyclic back extension exercise: a promising biomarker to detect early signs of sarcopeniashows the main reasons for not further processing the SEMG signal. Note that the EMG recordings were from three pairs of electrodes (L5 = multifidus, L2 = longissimus, L1 = iliocostalis lumborum) and the experiments were performed on three different daysBack to article page