Combination Therapy to Improve SCI Recovery.

Each participant will be exposed to 8 sessions of daily acute intermittent hypoxia via air generators over the span of two weeks. The generator will fill reservoir bags attached to a non-rebreathing facemask. Each session will consist of 15 episodes which include intervals of 1.5 minute hypoxia (FIO2=0.10±0.02, i.e. 10% O2) and 1 minute normoxia (FIO2=0.21±0.02).

Each participant will be exposed to 8 sessions of daily room air via air generators over the span of two weeks. The generator will fill reservoir bags attached to a non-rebreathing facemask. Each session will consist of 15 episodes of 1.5 minute normoxia (FIO2=0.21±0.02).

Individuals will participate in 45 minutes of gait training while having transcutaneous spinal cord stimulation. Stimulation intensity will be 80% involuntary motor threshold.

Individuals will participate in 45 minutes of gait training while having SHAM transcutaneous spinal cord stimulation. The stimulation will briefly increase to 80% involuntary motor threshold and then brought down to 0 within 30 seconds.