Inclusion Criteria:  >18 years Incomplete SCI above T12 >12 months post injury Respond to FES No deteriorating condition or other co-morbidity that would make participation impractical or unsafe. Marginal walker defined as able to rise from a chair, stand for 10 seconds and walk >10 steps without human help (but may use an aid including parallel bars).  Exclusion Criteria:  Cardiac pacemaker Pressure sores/skin problems Unhealed lower limb fractures Pregnancy Active heterotrophic ossification - lower limbs Severe osteoporosis Complex regional pain syndrome Implanted metal work at electrode site (< 3/12) Lower Limb Malignancy T6 and below spinal malignancy Uncontrolled autonomic dysreflexia History of knee dislocation/subluxation Allergy to electrodes Cognitive difficulties - must be able to demonstrate an understanding of the iCycle and the virtual reality cycling game Severe spasticity - Ashworth scale 4 or 5 in any lower limb muscle groups Neurological degenerative diseases