Clear structural effects
Researchers have also described clear brain structural and functional effects from being physically active. For example, MVPA has been shown to affect brain volume, and it has been associated with better optical coherence tomography (OCT) metrics, which measures retinal thinning.
As for the impact of exercise on memory deficits, which is of interest, given the current focus on Alzheimer’s disease, “the jury is still out,” said Dr. Yeh. One 24-week randomized controlled trial found no difference in results on the Brief Repeatable Battery of Neuropsychological tests between participants who engaged in progressive aerobic exercise and control persons.
However, said Dr. Yeh, “the problem may not be with the intervention but with the outcome measures” and potentially with the populations studied.
It might be a different story for high-intensity exercise, though. A study by Danish researchers assessed the effects of a 24-week high-intensity intervention among 84 adult patients with mild-severe impairment.
The primary outcome of that study, which was the percentage of brain volume change, was not met, possibly because the study was too short. There were significant results for some secondary endpoints, including improved cardiorespiratory fitness and lower relapse rate.
“Even though on the face of it, it sounds like a negative study, there were important outcomes,” said Dr. Yeh.
Research into the possible mechanisms behind positive effects of physical activity is limited with regard to patients with MS, said Dr. Yeh. Some studies have implicated certain circulating factors, such as the cytokine irisin and brain-derived neurotrophic factor, but more work is needed, she said.
“There is need for further mechanistic knowledge related to exercise in MS, and this must be accomplished through prospective, randomized studies.”
While exercise likely makes some difference for MS patients, the problem is in getting them to be more active. “You can’t just write a prescription,” said Dr. Yeh.
“Patients should be doing whatever they can, but gradually, and should not go crazy at the beginning because they’ll just burn out,” she said.
She stressed that patients need to find what works for them personally. It’s also important for them to find ways to be active with a friend who can be “a motivator” to help sustain physical activity goals, said Dr. Yeh.
Patients can also look online for remote physical activity programs geared to people with MS, which popped up during the pandemic.
Improved mood, cognition, pain, sleep
In a comment, Marwa Kaisey, MD, assistant professor of neurology at Cedars-Sinai Medical Center, in Los Angeles, who cochaired the session highlighting the presentation, praised Dr. Yeh’s “excellent talk,” which highlighted the “strong benefit” of exercise for patients with MS.
“As a clinician, I often talk to my patients about the importance of physical exercise and have heard countless anecdotes of how their workout programs helped improve mood, cognition, pain, or sleep.”
However, she agreed there are several areas “where we need more data-driven solutions and a mechanistic understanding of the benefits of physical exercise.”
The pilot study was funded by the Consortium of Multiple Sclerosis Centers. The MS Society of Canada funded early work on the app, and the National MS Society is funding the trial of the app. Dr. Yeh receives support from the MS Society of Canada. Dr. Kaisey reports no relevant financial relationships.
A version of this article first appeared on Medscape.com.