Does Exercise Reduce Risk for Multiple Sclerosis?

To evaluate the impact of physical activity on risk for multiple sclerosis (MS), investigators examined data from the Nurses' Health Studies (NHS). NHS 1 recruited 121,701 female nurses followed for up to 18 years, and NHS 2 recruited 116,430 followed for up to 20 years. Participants were sent biannual questionnaires about lifestyle, including medical conditions and time spent participating in physical activities. During follow-up, a new diagnosis of MS was identified in 341 women.

Compared with the lowest quartile of baseline activity, those in the highest quartile of activity had a 27% lower rate of MS diagnosis during follow-up. An overall trend between quartiles of activity was not significant. In an effort to determine whether early MS …