Multiple Sclerosis (MS) is a disease that affects the brain and spinal cord, leading to a gradual loss of nerve function. Canada—especially Saskatchewan—has the highest rates of MS in the world. Recent research in Saskatchewan has discovered that acute intermittent hypoxia (AIH) may help improve brain health in an animal model of MS. This same treatment has also shown benefits for people living with spinal cord injuries. Scientists are now studying whether AIH can help people in the early stages of MS. However, no one has yet tested this approach in people in the later stages of MS who often have few treatment options. Our study will be the first to explore AIH for brain health in people living with advanced MS.