Functional Electrical Stimulation (FES) can be used to assist patients with complete paraplegia arising from a traumatic spinal cord injury to stand. In clinical practice the take-up of this technology is poor. It was hypothesised that one potential reason was that the posture during standing was difficult to predict from non-standing biomechanical measures because of the spinal cord's motor responses to standing. In six patients biomecharrical and electrophysiological recordings were made to test whether motor activity arising as a result of standing affected their standing posture. Recordings were made using surface EMG electrodes, force plates and instrumented handles a motion analysis system. No motor activity that affected the posture of the patients was recorded during standing or when the patients changed their hip or ankle angles. The act of standing with FES assistance affected spasms in two of the six patients. In one patient his spasms became regularised to a 16s pattern when standing with FES but when standing without FES and in the second patient his spasms were stopped for periods of up to 7 hours. This prolonged cessation only occurred when standing with FES. Mechanically supported standing produced a short (5 minute) cessation in the activity. The neural activity during the sit-to-stand or steady state standing did not change with increasing experience of standing in one naive subject studied over 6 weeks. The patient used the same strategy for the sit-to-stand as other patients. He improved his performance of this strategy by shortening the phases and the intervals between the phases as well as reducing the safety margin for knee buckling. The spinal cord when removed from descending inputs is capable of generating rhythmical motor outputs in response to changes in sensory inputs. FES may interact with some of this oscillatory activity.