Inclusion Criteria:  between the ages of 21-70 years old  individuals with traumatic spinal cord injuries at the site C5-C6  duration of injury if more than 1 year non-ambulatory American spinal injury association scale A or B (motor complete) able to provide consent non-ventilator hypotensive (males: systolic blood pressure less than 110 mmHg and/or diastolic blood pressure less than 70 mmHg; females: systolic blood pressure less than 100 mmHg and/or diastolic blood pressure less than 70 mmHg) orthostatic hypotension (decrease in systolic blood pressure of at least 20 mmHg and/or decrease in diastolic blood pressure of at least 10 mmHg when moving from supine to upright position- will be determined in the screening process)  Exclusion Criteria:  acute illness or infection current smokers within 1 year of study documented history of controlled or uncontrolled diabetes any other neurological disease other than spinal cord injury cardiovascular disease (coronary artery disease, congestive heart failure, peripheral artery disease, stroke) present of history of thrombosis in the last 12 months, severe contractures