Comparative effectiveness of exercise types and doses for improving pain intensity in women with fibromyalgia syndrome: a systematic review and dose–response meta-analysis

Background Fibromyalgia syndrome (FMS) is a chronic condition characterized by widespread pain and substantial impairments in physical and psychosocial functioning, predominantly affecting women. Although exercise is recommended as a non-pharmacological approach for pain management in FMS, the dose–response relationships between different exercise modalities and pain remain unclear. This study aimed to compare the associations of different exercise modalities and doses with pain intensity in women with FMS. Methods Exercise dose was calculated as the product of duration, frequency, and intensity, expressed in metabolic equivalents of task minutes per week (MET-min/week), to enable comparisons across studies. Bayesian network and dose–response meta-analyses were conducted to compare the effects of different exercise modalities on pain and characterize their dose–response relationships. Pain was assessed using the Visual Analog Scale (VAS). Results A total of 24 studies were included in the systematic review, involving 1992 women with FMS. Overall exercise demonstrated a positive dose–response association with pain improvement, with the greatest effect observed at approximately 1400 MET-min/week (MD = −3.02, 95% CrI: −5.42, −0.52). Stratified analyses showed that aerobic exercise (AE), resistance training (RT), and mind–body exercise (MBE) were significantly associated with pain improvement, although the effective dose ranges and doses associated with the maximum effects varied across modalities. The effective dose ranges were 290–1400 MET-min/week for AE, 400–550 MET-min/week for RT, and 140–800 MET-min/week for MBE. The greatest improvements were observed at 1400 MET-min/week for AE (MD = −2.93, 95% CrI: −5.36, −0.49), 550 MET-min/week for RT (MD = −1.81, 95% CrI: −3.60, −0.06), and 800 MET-min/week for MBE (MD = −3.07, 95% CrI: −4.99, −1.09). Meta-regression analyses found no significant moderating effects of the examined study-level characteristics. Conclusions Different exercise modalities showed distinct dose–response relationships for pain improvement in women with FMS. MBE at approximately 800 MET-min/week was associated with greater improvement in pain intensity, although further high-quality randomized controlled trials are needed to confirm these findings. Systematic review registration : https://www.crd.york.ac.uk/PROSPERO/view/CRD420261478256 , identifier CRD420261478256.