Introduction and objectives: The most frequent and characteristic symptom of fibromyalgia is generalized and diffuse pain. The purpose of this study was to evaluate the effects of 12 weeks of physical training in warm water and subsequent detraining on the perception and intensity of pain and the number tender points in women with fibromyalgia. Methods: Thirty-five women with fibromyalgia were randomly assigned to 2 groups: an experimental group (n = 18), who exercised for 60 min in warm water 3 times a week, and a control group (n = 17), who did not receive the additional training. Pain was assessed using the dimensions of pain of the Fibromyalgia Impact Questionnaire and the Short Form-36. The number of tender points was also assessed. Results: After the 12-week training program significant improvements were observed in the perception and intensity of pain in the experimental group compared with the control group. However, after the detraining period, only the improvement in the "body pain" dimension of the Short Form-36 was maintained. The number of tender points showed no significant change in either group during the 24-week program. Conclusions: Addition of the physical training program to conventional care was effective in decreasing pain in women with fibromyalgia. After the detraining period, the improvements in pain were partially maintained. However, the physical training program had no effect on the number of tender points.