The purpose of the study is to compare the efficacy and tolerability of Ai Chi, an adaptation of Tai Chi exercise to water, with stretching on fibromyalgia symtomatology.

Physical therapies have shown to be effective in the treatment of fibromyalgia and It is generally assumed that a multidisciplinary approach, combining both pharmacologic and non-pharmacologic measures, is probably the optimal treatment approach for most fibromyalgia patients. As these patients are usually physically deconditioned, low-intensity exercise has been recommended at least as initial treatment. At this respect, exercise in warm water is considered a good option as both temperature and water buoyancy minimize body weight's stress and help patients to minimize pain. In a previous study comparing short term physiotherapy with stretching and Ai Chi we found that Ai Chi was at least as effective as stretching and induced a significant reduction in fibromyalgia core symptomatology and in sleep parameters. The objective of the present randomized controlled study is to compare both physiotherapy techniques in a long term basis.

Inclusion Criteria:

• diagnosis of fibromyalgia according to the ACR criteria
• 18 years or older
• written informed consent to participate

Exclusion Criteria:

• unable to tolerate warm chlorinated water
• associated medical condition contraindicating exercise in warm water