Exercise and locomotor training are commonly used in rehabilitative therapies in the spinal cord injured patient population.The main advantage of activity-based training is that many functional benefits have been documented, both in preclinical animal studies, and in clinical practice.Demonstrating the procedure will be James Armstrong, and Christine Yarberry, both senior research technicians, and Jason Gumbel, a graduate student from my laboratory.During the week before the spinal cord injury, handle each rat for five to ten minutes, once a day for five days.On the day of the injury, shave the hair from the back of the first 200 to 225 gram rat, at the site of the injury, and place the anesthetized animal on a heating pad at a low setting.Administer eye lubricant, a long-acting general antibiotic, an analgesic, and five milliliters of physiological saline.Estimate the location of the targeted lesion level, based upon the vertebral protuberances, and use a number 10 scalpel to make an approximately five centimeter incision on the dorsum of the animal, directly above the midline vertebrae.Using hemostats, retract lateral muscles, using 4-0 silk suture.For mid thoracic contusions, use rongeurs to remove the overlaying T7 vertebrae lamina, to expose the T8-T9 level of the spinal cord, and use a contusion device to perform the contusions.After delivering the injuries, use 4-0 diameter monofilaments to suture together the muscle and fascia over the spinal cord.And close the skin with nine millimeter surgical wound clips.Inject another five milliliters of physiological saline.Then place the animals in individual clean cages, on heating pads with close monitoring for the first 24-48 hours.Using the manual Cred