Many people with spinal cord injury (SCI) hold some ability to move their leg muscles, and are therefore considered to demonstrate a motor incomplete injury. After such a spinal cord injury, individuals are able to walk less both in their home and in their community. De-conditioning, or a lack of endurance and fitness also occurs. Several methods are available to try to improve walking ability and the fitness of persons with motor incomplete spinal cord injury. This study examines two of these methods. The first is the use of robotically assisted body-weight supported walking using a device called the Lokomat. The second is aquatic or pool-based exercise. The investigators are researching the impact of these two techniques on walking ability and fitness in people who experienced motor incomplete spinal cord injury for at least 12 months.

This research will occur in two centers Kernan Orthopedics and Rehabilitation Hospital in Baltimore, Maryland and Shepherd Center in Atlanta, Georgia. A total of 36 volunteers over a three year period are needed. In order to qualify for this study, individuals must be 18 to 65 years old with a motor incomplete SCI. The level of injury can range from the fourth cervical level in the neck to the twelfth thoracic level in the back. Potential volunteers must be able to tolerate standing in a standing frame for at least 30 minutes. Individuals will be assessed by a physician to determine their eligibility for the study and if participating in this type of exercise would be safe. Participants must be able to understand the study requirements and sign an informed consent document.

Participants will need to commit to a total of seven months. Included in this time is: testing, then the 3 months of exercise, testing, 2 week break, then the second 3 months of exercise, and a final testing. Half of the group will start with the Lokomat training and half will start wtih aquatic exercise. Each group will then switch to the other exercise condition. Exercise sessions will occur three times per week and last approximately 45-55 minutes. A physical therapist will provide personal direction for each of the exercise groups. Walking ability and cardiovascular fitness, as well as muscle strength will be assessed before starting exercise, at the three-month point and then at the six month point.

It is hoped that that this type of exercise therapy will help individuals with motor incomplete spinal injury both walk better and experience better heart-lung fitness and endurance. The risks associated with this type of study are similar to any type of cardiovascular exercise. In addition, individuals with spinal cord injury may present with some medical conditions, there may be other risks of the study. The physicians and therapists involved in the research will discuss these risks in detail with the individuals who enroll.

This type of research is important to better understand how best to prescribe exercise treatments to people with spinal injury. This is especially true with regards to aquatic therapy, since there is very little scientific data on its effect in this group of individuals. The rigorous assessment of aquatic exercise, which is already available in many communities, may expand the fitness opportunities for individuals with incomplete spinal cord injury.

Inclusion Criteria:

• Age 18-65 years
• Level of injury between C4 and T12 based on ASIA classification
• Chronic (greater than 12 months) spinal injury
• Completion of all conventional inpatient rehabilitation therapy
• Motor incomplete spinal cord injury (AIS C or D)
• Competency to provide informed consent
• Ability to tolerate a standing frame for at least 30 minutes

Exclusion Criteria:

• Currently performing aquatic therapy or Lokomat training as part of clinical care
• Complete or concurrent lower motor neuron injury as defined by the absence of reflexes bilaterally at the knees and the ankles
• Uncontrolled seizures
• Skin opening greater than 2 cm in diameter
• Alcohol consumption > 3 oz liquor, or 3 x 4oz of wine, or 36 oz of beer per day
• Cardiac history of (a) unstable angina, (b) recent (< 3 months) myocardial infarction, (c) congestive heart failure (NYHA category II), or (d) hemodynamically significant valvular dysfunction
• Medical history of (a) recent hospitalization for severe disease or surgery, (b)undiagnosed diabetics (fasting glucose > 120) or poorly controlled diabetics (those not on a stable regimen for >6 months) unable to be controlled with medical treatment, (c) significant orthopedic or chronic pain conditions limiting exercise, (d) active neoplastic disease, (e) pulmonary or renal disease, and (f) presence of any serious medical condition with a prognosis for death or dependency in the next 2 months
• History of long bone fracture in the legs
• Frequent bouts of autonomic dysreflexia (as determined by the principal investigator)
• Any other medical co-morbidities that based on the judgment of the local principal investigator would preclude safe participation in the study