A method and apparatus for stimulating the lower back and abdominal muscles in a patient comprising applying a first electrode A1/A2 substantially centrally to the lower lumbar region of the patient's body, and applying second and third electrodes B, C respectively to opposite side flanks of the patient's body. The electrodes are energised to apply a first group of muscular stimulation current pulses which flow between the second and third electrodes and a second group of muscular stimulation current pulses which flow between the first electrode and the second and third electrodes alternately.