E1 ReplicatedModerate confidencePEM not requiredRCTPeer-reviewedMachine draft
Standard · 3 min
Balneotherapy for the treatment of post-COVID syndrome: a randomized controlled trial.
Ovejero, Diana, Ribes, Anna, Villar-García, Judit et al. · BMC complementary medicine and therapies · 2025 · DOI
Quick Summary
Researchers tested whether balneotherapy (therapeutic bathing and aquatic exercises) could help people with long COVID symptoms. Ninety-eight adults with long COVID participated—half received 12 sessions of balneotherapy over one month, while the other half did not. The treatment group showed improvements in sleep quality, anxiety, pain, and fatigue compared to the control group, though some people experienced temporary worsening of fatigue during early sessions.
Why It Matters
This study addresses a critical gap in evidence-based treatments for long COVID/PACS, demonstrating that a non-pharmacological intervention can provide measurable symptom relief. For ME/CFS patients and researchers, it contributes to understanding mechanisms of fatigue and pain management while highlighting the need for careful monitoring of post-exertional worsening in exercise-based interventions.
Observed Findings
SF-36 energy/fatigue subscale improved significantly more in the balneotherapy group (β=-17.45, 95% CI [-24.23;-10.66], p<0.0001).
SF-36 pain subscale showed the most prominent improvement (β=-21.634, 95% CI [-30.48;-12.78], p<0.0001).
Sleep quality improved in the intervention group (Pittsburgh Sleep Quality Index β=2.641, p=0.003).
Anxiety symptoms decreased more in the balneotherapy group (Hospital Anxiety and Depression Scale β=1.72, p=0.023).
Seventeen patients (approximately 18% of completers) reported mild, transient worsening of preexisting symptoms, particularly fatigue and post-exertional malaise during early sessions.
Inferred Conclusions
Balneotherapy appears to be an effective short-term modality for alleviating fatigue, pain, sleep disturbance, and anxiety in post-COVID syndrome.
Water-based therapy may offer advantages over land-based exercise in early treatment phases due to buoyancy and reduced mechanical stress.
The observed post-exertional malaise exacerbation in some participants suggests balneotherapy must be carefully dosed and monitored, particularly in early sessions.
Remaining Questions
What mechanisms explain the apparent post-exertional malaise exacerbation in 18% of participants, and are certain patient subgroups at higher risk?
What This Study Does Not Prove
This study does not establish that balneotherapy is a cure or that its benefits persist long-term beyond the one-month follow-up period. It cannot definitively separate the effects of aquatic immersion from those of structured exercise, and the predominantly female, middle-aged sample with mild initial infections limits generalizability to other ME/CFS phenotypes. The transient worsening in some participants suggests potential harm in certain subgroups, requiring further investigation.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →