Hydrotherapy

Sandra Utz et al. (2025) · Biomedicines

This prospective observational study followed 101 adults with long-standing fibromyalgia syndrome (FMS) through a two-week integrative inpatient stay in Bamberg, Germany, with no control group. FMS is a chronic condition marked by widespread pain, fatigue, sleep problems, anxiety and depression, and the authors describe it as the third most common rheumatic disease. The program was built on classical European naturopathy: water-based therapies and heat, exercise, plant-based nutrition or medical fasting, herbal remedies and mind-body practices such as relaxation. The question was whether such a combined approach would ease symptoms at discharge and six months later. Of 134 patients who joined (127 women, ages 22 to 80), 101 returned questionnaires on admission, at discharge and after six months. During the stay they took part in meditative movement, physical therapy, hydrotherapy, lectures and cooking classes, and some had whole-body heat sessions or a 5-day fast on under 300 kcal a day. Pain, fatigue, anxiety, depression, stress and quality of life were measured with standard questionnaires (such as the HADS for anxiety and depression and the MFI-20 for fatigue) and compared over time with repeated-measures statistics. Overall pain intensity dropped from 71.5 to 63.0 on a 0-100 scale at discharge (a moderate effect, dz = 0.62) and was still lower at six months (64.4). Current pain fell sharply during the stay (6.56 to 4.37 out of 10) but crept back to 5.96 at six months. Fatigue improved from 71.1 to 63.3 and then partly returned (68.0). Anxiety and depression scores each fell by roughly 2.5 points at discharge and were still lower than baseline at six months. Stress and feelings of helplessness improved mainly after discharge, and mental quality of life rose between discharge and follow-up. Patients who fasted kept their pain gains at six months (p = 0.006), whereas non-fasters did not (p = 0.062), although this difference was borderline (interaction p = 0.050) and not randomised. The results come from an uncontrolled, single-centre sample in which a quarter of the participants did not complete the six-month questionnaire, so the changes cannot be attributed to the program alone. More than half the patients reported obstacles to continuing the methods at home, such as lack of time and exhaustion. The authors call for randomised trials with long-term follow-up and propose a follow-up day-clinic programme to help consolidate the learned self-management skills and everyday routines.

Suhas Balakrishna et al. (2026) · Journal of lifestyle medicine

This systematic review and meta-analysis pooled 33 controlled studies with 2,651 adults to ask whether pelotherapy, the application of mineral-rich mud, peat or clay as packs, wraps or full baths, eases musculoskeletal disorders. These include osteoarthritis (joint cartilage wear), rheumatoid arthritis (an autoimmune joint disease), fibromyalgia (widespread pain) and chronic low back pain. Pelotherapy is a traditional naturopathic practice used in spas, balneological centres and clinics in at least 40 countries, and the authors set out to test it against modern standards: pre-registration, risk-of-bias rating and GRADE certainty scoring. The team searched eight databases and trial registers up to April 2026. Included trials enrolled adults with a confirmed musculoskeletal diagnosis, applied mud as the main treatment for 10 to 21 sessions over two to three weeks, and compared it with sham treatment, usual care, waiting lists or nothing. Pain was mostly rated on a 0-100 mm visual analogue scale or a 0-10 numeric scale, and function on questionnaires such as the WOMAC. Two reviewers worked independently and combined results with random-effects statistics. Pain dropped clearly after mud treatment (standardised mean difference -0.74, a moderate-to-large effect, roughly 18.5 mm on the 100 mm scale and above the 15 mm threshold for a meaningful change). The effect was still present at 3 months (-0.61) and at 6 months (-0.49, low certainty). Physical function (-0.69) and quality of life (+0.58 on SF-36) improved as well, with osteoarthritis trials using the WOMAC at -0.82 and rheumatoid arthritis trials using the HAQ at -0.58. Morning stiffness (-0.52) and C-reactive protein, a blood marker of inflammation (-0.44), fell modestly, while the erythrocyte sedimentation rate did not change significantly. Knee osteoarthritis showed the biggest benefit (-0.86), and Dead Sea mud the strongest peloid effect (-0.84). Serious adverse events were no more common than in controls (relative risk 0.98); about 6.5% of mud recipients had mild, short-lived skin redness, largely from heat. The authors note several limits: participants cannot be blinded to mud, peloid type, temperature and protocol varied widely, results differed between trials (I2 = 62% for pain), a correction for possible publication bias lowered the pain estimate to -0.66, most trials came from European spa settings, and safety beyond 12 months is unknown. They call for larger blinded trials with standardised peloids and longer follow-up, and frame pelotherapy as an adjunct to, not a replacement for, drug and physiotherapy care.

Philipp Klemm et al. (2026) · European journal of physical and rehabilitation medicine

This randomized, double-blind, sham-controlled trial of 38 analyzed adults in Bad Nauheim, Germany, explored whether mineral water baths for the hands ease pain from hand osteoarthritis (HOA). HOA is wear-and-tear damage in the finger and thumb joints that causes pain, stiffness and reduced grip. Balneotherapy, the treatment of conditions with natural mineral waters, is well known for knee osteoarthritis, but evidence for hand osteoarthritis was thin. The tested water was natural thermal brine, a salty spring water (sodium chloride and hydrogen carbonate, rich in carbon dioxide), used at its natural 25 degrees C. Participants averaged 72 years, 86% were women, and all had painful, X-ray-confirmed HOA. One group soaked both hands in thermal brine and the other in ordinary tap water at the same temperature, in identical covered bowls so neither participants nor staff knew which was which. Each bath lasted 15 minutes, with six baths over three weeks. Pain was rated on a 100 mm visual analog scale (VAS, 0 meaning no pain), alongside hand function questionnaires, grip strength, skin blood flow and a blood marker (VEGF). After six baths, pain averaged 7 mm with thermal brine versus 33 mm with tap water, a 26.4 mm gap (P < 0.0001) larger than the 20 mm threshold for a clinically meaningful change. The gap was already present after the first bath (5.3 mm, P = 0.0017) and was still about 26 to 27 mm at 4 and 12 weeks. Pain on the hand index (AUSCAN pain subscore) was also lower (5.86 points, P < 0.0001), though that difference was gone at follow-up. Stiffness, function, grip strength, skin blood flow and VEGF did not differ between groups. Satisfaction favored thermal brine: 72% (13 of 18) rated pain relief good or very good versus 32% (6 of 19) with tap water. No adverse events occurred. The trial was small, ran at one center during the COVID-19 pandemic, and lost 12 of 50 participants, so only 38 were analyzed. Tap water may also have effects of its own. Because blood flow and VEGF showed no change, how the baths relieve pain remains unexplained; the authors note that 25 degrees C is below the 32 to 35 degrees C range where carbon dioxide baths are expected to widen blood vessels. They propose thermal brine baths as a non-pharmacological adjunct and call for larger multicenter trials with longer treatment and optimized temperatures.

Yang Zhu et al. (2026) · PeerJ

This systematic review and meta-analysis pooled 22 randomized controlled trials with 375 mostly male participants to ask when, if at all, a single cold-water immersion (CWI) after exercise helps muscles recover. CWI means immersing the body, from navel depth up to the neck, in water of roughly 5 to 20 degrees C for about 6 to 20 minutes. Exercise-induced muscle damage (EIMD) is the loss of force, soreness and raised creatine kinase (CK, a blood marker leaking from stressed muscle cells) that follows hard or unaccustomed exercise, often with delayed onset muscle soreness (DOMS). Earlier reviews mixed time points, so this one separated results at 0, 24, 48 and 72 hours. The included trials enrolled healthy non-athletes and athletes aged about 16 to 49, who exercised with intervals, simulated matches, distance running or heavy eccentric lifting. After exercise, one group sat in cold water and the comparison group rested seated for a similar time. Researchers measured maximal voluntary isometric contraction (MVIC, the hardest possible static muscle squeeze), countermovement jump (CMJ, jump height as a gauge of explosive power), CK, and soreness on a visual analog scale (VAS, a line marked from no pain to worst pain). Maximal strength was unchanged by CWI (g = 0.08, 95% CI -0.11 to 0.26, p = 0.42; a negligible effect) at every time point. Jump performance was worse immediately afterward (g = -0.68, p = 0.01; a medium-sized drop) and showed no difference by 24 to 48 hours (g = 0.38 at 24 h, p = 0.06; g = 0.06 at 48 h, p = 0.68). CK looked lower after CWI (g = -0.43, p < 0.001; a small effect), but the result shrank to non-significance after correcting for likely missing small studies (g = -0.16, 95% CI -0.44 to 0.12; the original benefit was probably overestimated). Soreness was lower (g = -0.58, p = 0.006; a medium effect), though the trials disagreed widely (I² = 87%) and the certainty of evidence was rated very low. The evidence has clear limits: 362 of 375 participants were male, participants could not be blinded to cold water, several trials were tiny, and only one immersion with follow-up of 72 hours or less was studied. The authors suggest the soreness effect is the most plausible benefit and the temporary jump decrement is the main drawback. Repeated use during training and its effect on muscle adaptation were not examined, and they call for larger trials that include women and standardize temperature and duration.

Tatiana Leite Müller et al. (2026) · International journal of biometeorology

This systematic review of nine studies with 465 adults looked at climatotherapy, the therapeutic use of climate and natural settings, for musculoskeletal and rheumatologic disorders such as osteoarthritis, rheumatoid arthritis, fibromyalgia and ankylosing spondylitis. The settings were the Dead Sea (very salty water, low humidity, distinctive solar radiation and air pressure about 5% above sea level) and coastal sites using thalassotherapy, which means bathing and exercising in seawater, sometimes with marine mud, sun exposure and sea air. Because these programs vary widely, the authors wanted to gather what trials say about pain, physical function, quality of life and safety. The reviewers searched three databases through September 2025 and included eight randomized trials and one non-randomized study from 1995 to 2011, mostly in Israel. Participants were aged 18 to 65 and stayed at a spa or coast for 10 days up to 12 weeks. Comparison groups used freshwater pools, usual care, pool exercise or the same program in Norway. Pain was usually rated on a 0 to 100 visual analog scale, and quality of life was measured with questionnaires such as the SF-36. Most studies reported short-term improvements in pain, stiffness, function and quality of life, mainly within groups. Only two studies could be pooled for pain, giving an inconclusive overall result (SMD -0.47, 95% CI -5.47 to 4.53; an interval too wide to show benefit or no benefit). Split by condition, osteoarthritis showed a large effect (SMD -1.01, meaning pain fell by roughly one standard deviation more than with comparison) while fibromyalgia showed a small non-significant one (SMD -0.18, p = 0.158). In fibromyalgia, single-study estimates showed fewer tender points (SMD -0.50, p = 0.0047) and better physical quality of life (SF-36 physical score 0.36, p = 0.0391), but mood scores (p = 0.5968) and overall fibromyalgia impact (p = 0.0612) did not change significantly. No serious adverse events were reported, though only one study recorded adverse events explicitly. The evidence has important limits: trials were small and published between 1995 and 2011, participants and therapists could not be blinded, safety was inconsistently recorded, and several programs combined many components, so the effect of the climate itself is hard to separate. Only one trial analyzed all participants as randomized, and the pooled estimate rests on two studies. Certainty was judged low. The authors suggest climatotherapy may be a complementary option, particularly for osteoarthritis, and call for multicenter randomized trials with standard outcome sets and systematic safety reporting.

Lolita Rapolienė et al. (2026) · BMC complementary medicine and therapies

This multicenter randomized controlled trial of 243 analyzed adults in Lithuania explored whether a short course of balneotherapy, a spa-based therapy using mineral water, therapeutic mud and salt, eases stress, anxiety and depression. Balneotherapy has a long tradition in European spa towns and is increasingly discussed as a complementary approach to stress-related mental health problems. The researchers wanted to know whether an 11-day standardized program works, whether adding a nature walk or an inpatient stay changes the results, and whether benefits last six months. Adults aged 18 to 65 who rated their stress as moderate to high were assigned to one of four groups: outpatient balneotherapy (64 people), outpatient balneotherapy plus nature therapy (63), an inpatient balneotherapy stay (64), or a no-treatment control group (52). The daily program combined a pool session with light exercise, a warm mineral water bath, a 20-minute sapropel mud wrap and 25 minutes of salt therapy. Questionnaires measured stress, depression, anxiety, fatigue, sleep and daily functioning, and saliva samples tracked the stress hormone cortisol, at baseline, right after treatment, and after 3 and 6 months. Right after treatment, people in all three spa groups reported clear improvements. Stress intensity dropped by about 2.6 points on a 10-point scale (p < 0.001), and depression scores fell by 10.7 to 12.5 points on an 80-point scale (p < 0.001), compared with a 1.3-point change in the control group (p = 0.253, no real change). Anxiety, fatigue and sleep problems improved too: fatigue fell by 4.1 to 5.1 points on the 10-50 Fatigue Assessment Scale (p < 0.001) while the control group did not change (p = 0.775), sleep quality rose by about 2 points on a 10-point scale (p < 0.001), and cortisol fell significantly in two of the three groups. Many gains were still present at six months, strongest after the inpatient stay. About 15% of participants had mild skin reactions to the mineral water, and no serious adverse events occurred. The authors suggest balneotherapy could be a safe complementary option for stress. Important limits apply: the paper reports mainly within-group changes rather than direct group comparisons, controls received no treatment, participants knew what they were getting, many people dropped out by six months, spa resources differed by center, and some questionnaires were not formally validated in Lithuanian. The control group also reported lower stress intensity (-1.18 points, p < 0.001), which shows that part of the improvement occurred without treatment. Larger, longer trials are recommended.

Meng-Si Peng et al. (2022) · JAMA network open

This assessor-blinded randomized clinical trial with 113 adults explored whether exercising in water (therapeutic aquatic exercise) works better over the long term than common physical therapy modalities for chronic low back pain, meaning pain lasting at least 3 months. The modalities were transcutaneous electrical nerve stimulation (mild electrical pulses applied through the skin) and infrared ray thermal therapy (heat delivered by infrared light). Aquatic exercise meant guided, active exercise in a pool, where buoyancy and water resistance change how the body carries load. The authors note that low back pain is common and costly, and that no earlier trial had compared these two approaches or followed participants for a full year. Participants were 18 to 65 years old (average 31 years; 59 women, 54 men) and were randomly placed into an aquatic exercise group (56 people) or a modalities group (57 people). Both groups attended 60-minute sessions twice a week for 12 weeks. The aquatic group did a 10-minute warm-up, 40 minutes of water exercise at moderate effort (about 13 on the Borg scale) and a 10-minute cool-down; the modalities group received 30 minutes of nerve stimulation and 30 minutes of infrared heat. Measurements at baseline, 3, 6 and 12 months used the Roland-Morris Disability Questionnaire (24 yes/no items on daily activities limited by back pain) and a 0-to-10 pain rating scale. The aquatic group had lower disability scores than the modalities group at every check: 1.77 points lower at 3 months (P = .006), 2.42 lower at 6 months (P = .006) and 3.61 lower at 12 months (P = .001), so the gap widened over time. At 12 months, 46.43% of the aquatic group improved by at least 5 disability points (a change the authors treat as clinically meaningful) versus 7.02% of the modalities group. Most-severe pain was 0.79, 1.34 and 2.04 points lower in the aquatic group at 3, 6 and 12 months. Sleep quality, fear of movement and overall quality of life (SF-36) also improved more with aquatic exercise (P = .02, P < .001 and P = .003 for the overall group-by-time effect). Not every measure separated the groups: overall SF-36 scores were nearly identical at 3 months (P = .92), and work-related fear-avoidance scores did not differ. Treatment-related pain was uncommon in both groups (3.6% versus 7.0%). The authors suggest that water-based exercise may offer longer-lasting benefit than passive modalities for chronic low back pain, in part because it is active exercise. They state clear limits: participants were mostly young with fairly low pain, no one could be blinded, the comparison group did not exercise so the water itself cannot be credited alone, and costs were not examined. The authors call for trials that add a land-exercise group, combine both approaches, and include older people with more severe pain.

Nicolas Vaillancourt et al. (2026) · Pain management

This two-arm randomized controlled trial with 36 adults compared 10 weeks of aquatic (pool-based) exercise therapy against a standard land-based care program for chronic low back pain (CLBP) — pain lasting more than three months without a clear structural cause. Beyond the usual measures of pain and disability, the study also tracked psychological factors that keep chronic pain going: pain catastrophizing (dwelling on and magnifying pain), kinesiophobia (fear of movement or reinjury), anxiety, depression, and sleep disturbance — factors most exercise trials for back pain don't examine. Participants, aged 18 to 65, trained twice a week for 60 minutes over 10 weeks, one-on-one with a certified athletic therapist. The aquatic group did dynamic lumbar-stabilization, core, hip and aerobic circuit exercises in a therapeutic pool, where water's buoyancy takes weight off the spine and its resistance still builds strength. The standard-care group received an individualized land-based mix of hands-on manual therapy (spinal mobilization, myofascial release) and progressive stabilization and strength exercise — reflecting the real-world care most people with CLBP actually receive. Thirty-four people completed the study; both groups attended more than 85% of sessions, and no one had an adverse event. Both programs worked: pain, disability, physical and overall quality of life, pain catastrophizing, and anxiety/depression all improved significantly in both groups by 10 weeks, with disability improvements (18-point and 13-point drops) comfortably clearing the threshold considered clinically meaningful, and neither group pulling statistically ahead of the other on any of these. The one place aquatic therapy stood out on its own was kinesiophobia and sleep: only the aquatic group's improvement in fear-of-movement scores and sleep-disturbance scores reached statistical significance, likely because moving safely and painlessly in water helps people rebuild confidence that movement won't hurt them. That said, the aquatic group wasn't statistically better than standard care on these two measures either — it simply crossed the bar for significance within its own group while standard care came close but didn't. These results support aquatic therapy as a genuinely comparable — and possibly, on fear of movement and sleep, slightly favorable — alternative to standard hands-on and land-exercise care for chronic low back pain. The study is small (34 completers), was originally powered to detect a different outcome in its parent trial, and its therapists weren't blinded to which treatment they were giving, so these encouraging psychological findings need confirmation in larger, purpose-built trials before they can be treated as settled.

Ángel Rodríguez-Ruiz et al. (2024) · Medicina (Kaunas, Lithuania)

This randomized controlled trial with 44 women explored whether a four-week "HAMMAM" program -- combining hydrotherapy (therapeutic water bathing at varying temperatures) and Swedish massage (a full-body technique using kneading, stroking, and tapping to relax muscle tissue and improve circulation) -- could ease pain in women with endometriosis-related chronic pelvic pain that had not improved with standard medical treatment. Endometriosis is a condition where tissue similar to the uterine lining grows outside the uterus, commonly causing pain during menstruation (dysmenorrhea, governing cyclical cramping) and intercourse (dyspareunia) that standard analgesics and hormonal therapy fail to relieve in roughly a third to half of patients. Women aged 20-50 with confirmed endometriosis and pelvic pain rated at least 4 out of 10 were randomly assigned to the HAMMAM group (21 women) or a control group continuing usual care (23 women) at a hospital in Granada, Spain. The HAMMAM group attended three 90-minute sessions over four weeks at a bathhouse: a 60-75 minute circuit of warm, hot, and cold water baths plus a steam room, then a 15-minute Swedish massage with essential oils; the last session added a traditional exfoliating scrub. Pain was measured on a 0-10 scale, and pressure sensitivity with a handheld algometer. The HAMMAM group reported significantly less menstrual pain (p = 0.035, a large effect) and pain during intercourse (p = 0.020, a moderate-to-large effect) after the program compared with the control group. Pain interfering with sleep also dropped notably (p = 0.018), and pressure pain thresholds in the pelvic region rose (p = 0.029, meaning the area became less sensitive to pressure -- a sign of reduced pain sensitization), with the strongest change at the left groin ligament (p = 0.006). Everyone attended all sessions (100% adherence) and rated satisfaction at 9.71 out of 10, with no adverse events. However, overall pelvic pain ratings, catastrophic thinking about pain, general subjective well-being, and endometriosis-specific quality of life did not change significantly, showing the benefits were concentrated in specific pain measures rather than global wellness. For women whose endometriosis pain persists despite conventional treatment, this suggests a short, low-intensity spa-style program combining water therapy and massage may meaningfully ease menstrual and intercourse pain and pain-disrupted sleep, with high satisfaction and no safety concerns. Because hydrotherapy and massage were only tested together, it is not yet known which component -- or their combination -- drives the benefit, and the small, single-site sample limits how broadly these results apply. Larger trials testing each therapy alone are needed before firm clinical recommendations can be made.