The device comprises: detection means with several electromyography sensors (11) which can be arranged in contact with the skin of a user on at least one muscle for acquiring electromyographic signals； electronic means for performing at least the conditioning of said acquired electromyographic signals, conversion of the signals to a digital format and transmission of the digitized electromyographic signals to a control unit (30) through a communication channel (26) for monitoring same； and a flexible sheet support, integrated by two independent, overlapping layers, a first support layer (C1) including the detection means and a second support layer (C2) including the electronic means, said two support layers (C1, C2) being mechanically and electrically attached in a detachable manner by means of electro-conductive couplings (39).
