EXpain Trial - Exercise an a Non-pharmacological Pain-relieving Treatment in People With Multiple Sclerosis

The primary goal of this study is to test whether 12 weeks of progressive resistance exercise is an effective non-pharmacological treatment for reducing pain in people with multiple sclerosis and chronic pain. The study will be a randomized controlled trial with multiple training sites. After baseline testing, participants will be randomly assigned to either a 12-week progressive resistance exercise intervention followed by a 12-week follow-up period or to a 24-week waitlist control group that receives usual care. It is hypothesized that people with multiple sclerosis and chronic pain who receive the intervention will experience greater reductions in pain (i.e., clinically relevant reductions) compared to the waitlist control group (primary hypothesis), and that this pain reduction will be preserved after a 12-week follow-up period (secondary hypothesis).