How Does Intermittent Hypoxia Amplify the Functional Benefits of Task-specific Rehabilitation after Spinal Cord Injury?

Spinal cord injury impairs motor function, leading to chronic disability. Traditional exercise-based (task-specific) training alone is insufficient to restore motor function. An emerging rehabilitation strategy is to precondition the nervous system by breathing repeated episodes of low oxygen, a treatment known as therapeutic acute intermittent hypoxia, which strengthens spared synaptic pathways to motor neurons, improving movement. When combined with task-specific training, considerable improvement in motor function is observed through unknown mechanisms. In this article, authors propose hypothetical models of neural network and cellular elements giving rise to synergy between therapeutic acute intermittent hypoxia and task-specific training. Their intent is to encourage and guide future research that will improve the chances of successful human clinical trials.