Aerobic exercise strengthens brain connections in people with relapsing-remitting multiple sclerosis (RRMS), Jan-Patrick Stellmann, with University Medical Center Hamburg-Eppendorf in Germany, reported at the 7th Joint ECTRIMS-ACTRIMS Meeting in Paris that ran from Oct. 25–28.
According to Stellmann, “aerobic exercises are considered to improve mobility, fatigue, depression and cognition in MS,” and also to “promote neuroprotective or neuroregenerative mechanisms.”
For the study, “Aerobic exercise induces functional and structural reorganization of the brain network: Results from a randomized controlled trial in relapsing-remitting multiple sclerosis,” the team used magnetic resonance imaging (MRI) to examine how exercise affected different types of brain connections.
They recruited 57 RRMS patients and 30 healthy controls to the study. Women made up more than two-thirds of the patient group, which had a mean age of 39. Patients only had mild disability, with a mean score of 1.5 on the Expanded Disability Status Scale (EDSS).
Researchers randomly assigned about half the group to a supervised and individually adapted aerobic exercise program, consisting of 22 sessions of up to one hour each. Others were assigned to a waiting list — with the intent of taking up exercise after three months — and served as a control group.
MRI scans at the study’s beginning revealed that patients had more so-called functional connections, but fewer structural ones, than healthy controls. It is known from earlier studies that most RRMS patients show abnormalities in functional connections, but some researchers find increases while others decreases in these connections.
Functional and structural connections appear on different types of MRI scans — ones that make use either of blood flow changes or of the properties of water molecules in the white matter of the brain.
The deviations were particularly pronounced in highly connected hub regions, the researchers said.
After three months, functional connections increased across the entire brain among exercising patients, but decreased in those on the waiting list. Structural connections also increased among patients who exercised, while no change was detected among control patients.
Researchers also noted that exercising patients grew more local connections, mostly in hub regions, compared to those who did not exercise.
While it is generally accepted that aerobic exercise promotes neuroprotective and regenerative processes within the brain, the study demonstrated that exercise, in only three months, did indeed affect how the brain is wired.
“Short-term aerobic exercise increases functional and structural connectivity,” Stellmann concluded. “Already after three months, exercise lead to functional and structural reorganization of brain networks.”
The researcher highlighted the difficulties in obtaining financial support for trials on exercise. And he emphasized that patients should be encouraged by their doctors to exercise regularly.