In order to clarify why orthopedic complaints such as lumbago are ameliorated by hot-spring bathing, serum levels of sialic acid and fucose, which form glycoconjugates and are markers of connective tissue metabolism, were measured before and after each hot-spring bathing. No changes were observed in serum sialic acid for persons who took hot-spring bathing more than three times per day for 10 days. However, many of them showed a decreasing tendency in serum fucose level after bathing. Although it is not clear why this tendency occurs, it strongly suggests that hot-spring bathing influences on connective tissue metabolism.

It is well known that gynecological complaints are ameliorated by hot spring bathing. We therefore investigated the changes in urinary mucin excretion before and after 14 days of daily hot spring bathing in order to clarify the relationship between hot spring bathing and complaint amelioration. Urine was collected from 28 female adults (64.3±7.0 years old) before and after the 14 days of hot spring bathing. Urinary mucins containing sialoglycopeptides and sulfated glycopeptides were separated from the urine using the ethanol and cetylpyridinium chloride precipitation methods, then indentified with two-dimensional electrophoresis on cellulose acetate membranes.
After the removal of glycosaminoglycan contamination by glycosaminoglycan-degrading enzymes, mucin amounts were determined by the phenol-sulfuric acid method. The results showed that the levels of both sialoglycopeptides and sulfated glycopeptides increased after 2 weeks of bathing. The level of urinary mucin, which is synthesized and excreted from the epithelial cells, increased as a result of hot-spring bathing. Therefore, it is highly likely that the amelioration of gynecological complaints of females is related to the chages in urinary mucin excretion brought about by hot spring bathing.

Objectives: The purpose of this study was to examine the beneficial effects of balneotherapy in patients with chronic heart failure (CHF).
Background: Some reports have shown that balneotherapy reduces systemic blood pressure in healthy volunteers. However, it is not clear whether balneotherapy improves the status of CHF. We hypothesized that hyperthermia using hot water would improve cardiac and peripheral endothelial function and clinical symptoms.
Methods: Twenty-six patients with chronic systolic heart failure classified as New York Heart Association (NYHA) functional status II or III were divided into two groups. In the balneotherapy group, patients were immersed in a hot spring at 40°C for 10min daily for two weeks; in the control group, patients took a daily shower. We measured plasma brain natriuretic peptide (BNP) and asymmetric dimethylarginine (ADMA). The left ventricular ejection fraction (LVEF) and cardiothoracic ratio (CTR) were evaluated by echocardiography and chest radiography, respectively. Brachial-ankle pulse-wave velocity (baPWV) was measured non-invasively using an automatic device.
Results: Clinical symptoms were improved after two weeks of hot spring therapy. Although heart rate and CTR did not change, clinical symptom and LVEF improved and mean blood pressure, BNP, ADMA and PWV significantly decreased.
Conclusions: Repeated immersion in a hot spring improves peripheral vascular endothelial function, thus leading to improvement of clinical activity and symptoms in patients with CHF.