A large body of evidence shows that spinal circuits are significantly affected by training, and that intrinsic circuits that drive locomotor tasks are located in lumbosacral spinal segments in rats with complete spinal cord transection.
However, after incomplete lesions, the effect of treadmill training has been debated, which is likely because of the difficulty of separating spontaneous stepping from specific training-induced effects.
According to a study published in Neural Regeneration Research (Vol. 8, No. 27, 2013), a rat model of spinal cord contusion at the T10 level was used to examine the effect of step training. After 3 weeks of step training, the rats with spinal cord contusion at the T10 level exhibited a significantly greater improvement in the Basso, Beattie and Bresnahan score.
The expression of growth-associated protein-43 in the spinal cord lesion site and the number of tyrosine hydroxylase-positive ventral neurons in the second lumbar spinal segment were greater at 11 weeks post-injury, while the levels of brain-derived neurotrophic factor protein in the spinal cord lesion site showed no changes.
These results suggest that treadmill training substantially improved spontaneous motor activity in rats with incomplete spinal cord injury.
The improvement in rat behavior was associated with a significant increase in growth-associated protein-43 expression in the injured spinal cord and in tyrosine hydroxylase expression in the second lumbar spinal segment. Treadmill training significantly improves functional recovery and neural plasticity after incomplete spinal cord injury.