Influence of gender on the myoelectric signal of shank muscles

The surface electromyographic (sEMG) signal is commonly utilized as principal input information to the controller of robotic systems, such as exoskeleton robots. It has been shown that sEMG signals could vary from subject to subject, and that gender is one of the factors influencing this variation. Thus, the goal of this study is to detect possible gender-related differences in the EMG activity of the two main ankle-flexor muscles (tibialis anterior, TA and gastrocnemius lateralis, GL) during gait at comfortable speed and cadence. The statistical analysis of surface EMG signals, performed in seven male (M-group) and seven female (F-group) age-matched adults, showed clear gender-related differences in the behavior of TA and GL. The estimation of the different activation modalities, indeed, permitted to detect that F-group choose a walking modality with a more elevated number of activations during gait cycle, compared to M-group. This suggests a propensity of females for a more complex recruitment of the muscles during gait. The novel information on gender-related differences provided here suggest considering a separate approach for males and females, in providing electromyographic signals as input information to the controller of exoskeleton robot.