Do X-trodes EMG montages really measure the electrical signals from my muscles?

 X-trodes provides three montages for measuring electrical signals from muscles: the xtr EXG16, with 16 channels for accurate muscle activity localization, xtr fEMG16 for simultaneous measurement of EMG and frontal EEG from the face, and xtr EXG2, a compact patch with 2 channels for various muscle measurements.