Fibromyalgia (FM) is a prevalent and disabling disease, that affects mostly women and its main characteristic is chronic pain. Several studies have shown that hydrotherapy is effective in the improvement of symptoms and quality of life of this population; other studies have shown that Pain Therapeutic Education (PTE) is also effective in this sense. PTE is one cheap, easy to apply intervention, with very positive results in chronic pain situations. However, there is a lack of studies that have shown the effects of this intervention on FM. Hence, this study will aim to verify the effectiveness of the hydrotherapy and PTE on women with FM. Sixty women will be randomly allocated in two groups: hydrotherapy and hydrotherapy + PTE. Before treatment start, the investigators will evaluate pain (visual analogue scale, presence of myofascial trigger points and pressure pain threshold over the scalene, upper trapezius, infraspinatus, piriformis, iliopsoas and soleus, bilaterally), quality of life (Fibromyalgia Impact Questionnaire and medical outcomes study 36-item short-form health survey), depression (Beck Depression Inventory), anxiety (Beck Anxiety Inventory) and sleep quality (Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale). Hydrotherapy treatment will last 12 weeks. Women will be evaluated other 3 times: after 6 and 12 weeks (treatment middle and end) and 12 weeks after treatment completion (follow-up). Women in the hydrotherapy group will receive a folder with explanations on FM. Women in the hydrotherapy + PTE will participate of 4 meetings over 12 treatment weeks, in which themes like pain physiology, pain chronification and exacerbation and pain self-management, as well as information on FM will be approached. Statistical analysis will include qualitative and quantitative variable description. Correlation among variables will also be analyzed. Level of significance will be set at 5%.

The investigators will select at least 80 women with fibromyalgia (FM) for this study, in which pain (through pressure pain threshold and number of active myofascial trigger points), quality of life, FM impact on quality of life and function, depression, anxiety and quality of sleep will be evaluated.

After evaluating the volunteer, the participant will be randomly allocated to one of two groups: hydrotherapy treatment (HT), and hydrotherapy treatment together with pain therapeutic education (HT+PTE).

All volunteers will perform 12 weeks of hydrotherapy treatment, in which the investigators will perform global exercises for upper and lower limbs and trunk.

Volunteers in the HT+PTE group will receive, throughout the 12 weeks of HT, 4 sessions of PTE, in which the investigators will teach pain neurophysiology, pain chronification and pain management.

Evaluation sessions will take place before treatment, after 6 and 12 weeks of HT and after 12 weeks of treatment ending.

In all evaluations sessions, the investigators will collect data on those aspects previously described.

Inclusion Criteria:

• Clinical and medical Fibromyalgia Diagnosis according to ACR Diagnostic criteria 2010 and 2016;
• Willing to perform hydrotherapy as treatment.

Exclusion Criteria:

• Cognitive deficits that prevent volunteers from understanding evaluation and treatment procedures;
• Uncontrolled systemic illnesses (diabetes, hypertension);
• Neurological and musculoskeletal conditions that may interfere in the evaluation and treatment procedures (palsies, sensitivity alterations, advanced osteoarthritis);
• Infecto-contagious illnesses (especially in the urinary tract);
• Alcohol or drug abuse;
• Pregnancy.

All results shall be disclosed in a form that no individual volunteers shall be identified.

Outcomes assessor will not know in which group volunteers are allocated; Care provider will not know outcome measures for any volunteers before study completion.