Aerobic walking exercise may boost cognitive function in multiple sclerosis
Experts believe that MS develops when an unknown trigger turns the immune system
ISLAMABAD, (Online) - Multiple sclerosis (MS) is a chronic disorder that affects the brain, spinal cord, and optic nerves. The National MS Society estimates that nearly 1 million people in the United States live with the condition.
Cognitive processing speed (CPS) impairment is a common MS symptom that can improve with exercise. However, many people with MS have challenges with accessibility to exercise training programs.
Experts from the Kessler Foundation in New Jersey recently ran a pilot study assessing the effectiveness of remote aerobic walking exercise training on CPS in fully ambulatory people with MS.
They hypothesized that this “form of physical rehabilitation represents a promising and potent behavior for managing CPS impairment in MS.”
The team observed moderate CPS improvements in participants who walked compared to individuals who were prescribed stretching activities.
Dr. Brian M. Sandroff, senior research scientist at the Kessler Foundation, was the lead author of the resulting article published in Multiple Sclerosis and Related Disorders in April 2023.
Cognitive impairment in multiple sclerosis
Experts believe that MS develops when an unknown trigger turns the immune system against the central nervous system (CNS). This damages the nerves’ protective layer — called myelin — disrupting neural signaling throughout the CNS.
Consequently, people with MS face unpredictable symptoms including memory problems, pain, numbness, mood changes, and even paralysis.
Cognitive impairment is a common condition affecting between 45% and 70% of people with MS. It is associated with diminished quality of life, work performance, and social participation. CPS impairment is a form of cognitive impairment that often occurs in MS.
To date, treatments for MS, such as first-line corticosteroids and cognitive rehabilitation, have had limited effectiveness in treating CPS impairment.
How exercise may help
Medical News Today discussed this study with Dr. Barbara Giesser, a neurologist and MS specialist at Pacific Neuroscience Institute at Providence Saint John’s Health Center in Santa Monica, CA. She was not involved in the present research.
Dr. Giesser explained: “There are currently no established pharmacologic treatments for cognitive impairment in persons with MS. Cognitive rehabilitation as well as programs that provide both physical and cognitive stimulation may be helpful.”
Mounting research attests to the potential of exercise to provide such stimulation.
A 2021 study in the International Journal of Environmental Research and Public Health stated that, “[i]n persons with MS, exercise can decrease neural apoptosis and neurodegeneration, and may be effective at stimulating neuroplasticity, as overall exercise increases neurological functioning.”
Barriers to exercise
Dr. Giesser also shared that people with MS face significant barriers to regular exercise. For instance, there may be limited or no access to facilities and a lack of transportation.
Some people with MS feel unable to work out due to financial barriers, lack of self-efficacy, or concerns about making symptoms worse, the neurologist told MNT.
The study methods
The Kessler Foundation team followed 25 fully ambulatory people with MS, 19 of whom completed the study. The participants were between 18 and 65 years of age, prescreened for CPS impairment, and were considered “insufficiently physically active” based on a questionnaire.
These people did not demonstrate severe cognitive impairment or mental disorders that would affect cognition.
They participated in randomly assigned, remotely delivered aerobic walking exercise training (intervention group) or stretching and range-of-motion activities (control group). Both groups were advised to complete their exercises three times a week and also received regular 1:1 coaching with an exercise specialist via scheduled Zoom calls.
The coaching, paired with a wearable fitness tracker, served to ensure proper technique, safety, and compliance with their prescribed regimens.
The researchers evaluated the participants through the Symbol Digit Modalities Test (SDMT) to measure information processing speed in individuals with MS, and the California Verbal Learning Test (CVLT-II) to gauge verbal learning and memory. Testing occurred at baseline and after 16 weeks.
More exercise, better cognitive function
The researchers found that the intervention condition group showed higher SDMT scores at the end of the study compared to the control group.
The participants finished an average of 80% of their prescribed sessions.
The Kessler Foundation experts believed that the removal of time and travel barriers “was most likely the primary driver of successful and efficient recruitment.” They said that this is promising for implementing a similar trial for people with MS-induced CPS impairment on a larger scale.
Implications and limitations
This study shows that remotely delivered exercise programs might work just as well as in-person sessions for fully ambulatory people with MS.
Dr. Giesser said that “this important study adds to the growing body of evidence that physical activity or exercise can improve cognitive function in persons with MS.”
The study authors mentioned several limitations to their research, however.
A small budget and short time frame led to a small sample size. The participants were all female, highly educated, and had mild MS