Effects of pool-based exercise in fibromyalgia symptomatology and sleep quality: a prospective randomised comparison between stretching and Ai Chi.

To evaluate the effectiveness and tolerability of two pool-based physical therapies, stretching and Ai Chi, in fibromyalgia symptomatology and sleep quality.Eighty-one patients, randomly assigned to stretching (n=39) or Ai Chi (n=42), received 18 physiotherapy sessions and were evaluated at baseline, at treatment termination, and after 4 and 12 weeks of follow-up. Main outcome measures were the Fibromyalgia Impact Questionnaire (FIQ) and the Pittsburgh Sleep Quality Index (PSQI). Secondary outcome measures included the Beck Depression Inventory (BDI), the State and Trait Anxiety Inventory (STAI), and the SF-12 Health Survey (SF-12). Data analysis was done with repeated measures ANOVA and effect size estimation.No differences were found between groups but significant reduction in the FIQ and the PSQI scores were observed in Ai Chi but not in stretching group, with larger effect sizes and longer effect duration on sleep measures. BDI scores decreased in stretching but not in Ai Chi group with small effect sizes. Trait-anxiety scores decreased in both groups also with small effect sizes. The mental component summary of the SF-12 increased only in stretching group with effect sizes moderate to large.Although no global differences were found between groups, Ai Chi significantly improved fibromyalgia symptomatology and sleep quality, whereas stretching only improved subjects' psychological well-being.