A garment worn by the patient is provided. The garment has a first module electrically connected to a second module. The first module has a first sub-control unit electrically connected to a first electrode and a second electrode placed at a first muscle of the patient and a third electrode and a fourth electrode placed at a second muscle. The sub-control unit is electrically connected to a master unit. The first muscle is stimulated with a first stimulation signal without shortening the first muscle by sending the first stimulation signal to the first electrode placed at the first muscle. The stimulation of the first muscle relaxes the second muscle. A measuring unit (U1) of the master unit determines a first current value flowing from the first electrode through the first muscle to the second electrode and sends the first current value to a central processing unit (CPU). The CPU compares the first current value to a current reference value and increases a voltage of the first stimulation signal when the first current value is below the current reference value.