<qa>  How many patients will be recruited to participate in this study?Sixteen patients with incomplete SCI will be recruited to participate in this study. Baseline evaluations will include American Spinal Injury Association classification, rate-sensitive depression, phase-dependent H-reflex modulation at self-selected and fast overground walking velocities, and MRI of the spine. Patients will wear a step activity monitor for a 48-hour period, quantifying baseline walking activity level. 