The muscle conditioning program is accomplished through electrical stimulation of the quadriceps and hamstring muscles using a 4-channel electrical stimulator that applies stimulation using surface electrodes adhered using gel to the skin overlying the quadriceps and hamstrings muscles. The muscle strengthening initially takes place three times per week, sixty minutes per session, progressing up to five sessions per week, for approximately 8 weeks. The muscle strengthening program ensures that subjects have sufficient muscle strength and endurance before they embark on the rowing program. Following the 8-week muscle strengthening program, subjects will begin FES-rowing, with three sessions per week, thirty minutes per session for the following 28 weeks. In the FES-rowing group, the investigators will measure isometric knee extension strength at the start of week 0, and at the end of weeks 12, 24 and 36.