An exercise system for exercising at least one limb, such as the legs, of a subject with spinal cord injury or deficiency. The system comprises an exercise bicycle having a crank and pedals to which the feet of the subject can be mounted, and a functional electrical stimulation (FES) system. The FES system stimulates the muscles of the legs and includes a transducer mountable to at least one of the legs of the subject that outputs signals representative of the position and/or movement of the leg when performing the exercise. The FES system further includes a control means that receives and processes the signals output by the transducer and outputs control signals to a stimulator that through electrodes provides electrical stimulation to the legs of the subject so as to cause the legs to drive the crank of the bicycle.