The main negative effect of electrical stimulation is muscle discomfort and / or fatigue of the lower limbs during and after training. Patients will be were asked at the beginning and end of the training on their sense of fatigue / tiredness members, as well as on the feeling of muscle pain. In addition, the current was adjusted individually and gradually increased shape with patient consent. In the case that patients feel a discomfort, the intensity of electric current was reduced, and if required the protocol was stopped by improvement of symptoms.