The goal of this clinical trial is to investigate the effects of transcutaneous spinal cord stimulation (TSCS) combined with exoskeleton training, as compared to exoskeleton training alone to improve motor function in individuals with incomplete spinal cord injury who are 12 months or less post-injury. Participants will be randomly assigned to a treatment group (exoskeleton training with TSCS, or exoskeleton training without TSCS). Participants in both groups will undergo a baseline evaluation, then take part in 24, 1-hour training sessions at Craig Hospital. After the 24 sessions have concluded, participants will undergo a post-treatment evaluation as well as a follow-up evaluation four weeks after training is completed. Researchers will compare the two groups by evaluating the following areas: * walking ability and speed * lower extremity strength, activation, and spasticity * trunk control * bowel and bladder function