<p>Neurorehabilitation of motor functions using neural interfaces with feedback is a modern and promising area of research. However, the literature contains very little on the extent of muscle activation during the imagery of lower limb movements, which is an important aspect in rehabilitation. The work reported here analyzed the EMG activity of the lower limb muscles in 42 healthy experimental participants working with a neural interface based on kinesthetic imagery of dorsiflexion of the feet and supplemented with a “Biokin” robotic device for moving the limbs (mechanotrainer), activated when motor imagery was successful. On average for all experimental participants, working with the neural interface was found to lead to increased activity in the muscle whose movement provides the imagined movement in reality, i.e., the tibialis anterior muscle (TA). In addition, the activity of the gastrocnemius muscle – the antagonist of TA – increased, which appears to be associated with the instruction to imagine the movement but not to make it. Mechanotrainer activation (MTA) additionally increased the EMG activity of the TA (by up to 100–200%) and weakly but significantly (by 3–5%) decreased the activity of the thigh muscles (quadriceps and left biceps). Consequently, MTA enhanced addressing of the influence of the descending signal arising during motor imagery. Muscle reactions to motor imagery were individual. Thus, application of neural interfaces based on imagery of dorsiflexion of the feet and the use of a mechanotrainer ensuring closure of the feedback loop during imagery of this movement contributed to targeted activation of the TA, the muscle providing foot dorsiflexion, which is important for the clinical rehabilitation of paretic foot movements.</p>