Regular exercise sessions for children with multiple sclerosis (MS) may help to mitigate the effects of the debilitating disease, scientists have reported.

The findings of a recent study published in the journal Neurology, explored how lifestyle factors play a role in the severity of a condition and noted a positive association with regular physical activity.

Previous studies have also indicated that physical activity may help counter the physical symptoms of MS and delay the associated cognitive impairment, while the benefits of massage in fighting the disease are also currently being explored.

"Up to three-quarters of children with MS experience depression, tiredness, or memory and thinking impairment," said author of the latest study E. Ann Yeh, associate professor at the University of Toronto. "Our research is important since little is known regarding how lifestyle behaviours may affect the disease."

For the study, 31 children with MS and 79 who had experienced a single inflammatory neurologic event were given questionnaires about tiredness, depression and how often they exercised. Of those, 60 were also given MRI brain scans to measure brain volume and the amount and type of MS lesions they had.

Only 45 per cent of the children with MS reported participating in any strenuous physical activity, compared to 82 percent of the other children. The children with MS who took part in strenuous physical activity were more likely to have a lower overall volume of lesions in the brain that indicate disease activity, than the children with MS who did not do strenuous activity.

The scientists found those who carried out strenuous activity had a median of 0.5 relapses per year, compared to one per year for those who did no strenuous activity. The results were the same after researchers adjusted for the severity of the children's disease.

"These findings add to the possibility that physical activity may have a beneficial effect on the health of the brain," said Yeh, who cautioned that the study does not determine a cause-and-effect relationship between physical activity and disease activity in MS, showing only an association between the two.