ABSTRACT
<b>Purpose</b><br> Electrodermal activity (EDA) is well known to be influenced by sympathetic activity. Although spa bathing alters autonomic nervous function, the effects of spa bathing on EDA have not been determined. We therefore examined the influence of spa bathng on EDA and autonomic nervous function. <br><b>Method</b><br> When a gold electrode in test solution and another electrode on the palm were connected to a voltmeter and the index finger was inserted into the test solution, the maximum change of potential shown on the voltmeter was considered as EDA. Several kinds of spa water, tap water, refined water and alkaline ion water were used as test solutions. Electric conductivity, pH, oxidation reduction potential (ORP) and temperature were also measured. Five adult women participated in these tests.<br>To examine influences on the autonomic nervous system, Fourier analysis of the RR interval of heart rate was perforrned for three volunteers using electrocardiography before and after bathing in sulfur spa or tap water. <br><b>Results</b><br> EDA displayed an extremely positive correlation to ORP, a weak negative correlation to pH and barely any relationship to electric conductivity of test solutions. Spectrum density at 0.04-0.15 Hz under Fourier analysis (LF) increased after sulfur bathing, but decreased after tap water bathing.<br>Discussion and conclusion : As EDA strongly correlated to ORP of solutions, epidermal cells may generate electric potential by extracellular ORP which may also produce intracellular electric potential altering membrane potential and consequently autonomic nervous functions might be influenced by the changed EDA.<br> Since LF is consider to mainly comprise a parasympathetic component in resting state, the results of LF may indicate that the balance of autonomic nervous activity of the heart becomes more parasympathetic dominant after sulfur bathing and more sympathetic dominant after tap water bathing.<br>From above mentioned, bathing may have an electric influence on the human body by the ORP of bathing water.
ABSTRACT
To examine effects of travel and spa spring to bath death, that of visitors and residents were extracted from inquests from 1984 to 2007 at Naruko Police Office. Total bath death was 192, of which 128 visitors and 64 residents. Average number of visitors per year was 261,000, and average population of residents was 25,468. During first half period bath death of visitors was 80 and residents 15, whereas during latter half visitors 48 and residents 49. Despite day-trippers were as more as 1.5 times to 2.5 times than visitors, bath death of them was scarcely seen. Average mortality rate of bath death for 100,000 of visitors during first half was 225, and in latter half 174, while that of residents was 4.5 in first half and 17.4 in latter half. Therefore ratio of mortality rate of visitors to residents has been ten times or more. Bath death had increased in winter, at from 20:00 to 2:00, on over 40 Celsius degrees of temperature of bathtub, on 20 Celsius degrees or more of temperature difference between bathtub and room, in seniority from 75 to 85 years old, and in drinkers. It was suggested that because bath death was scarcely seen in day-trippers which were more than visitors, risk factor of bath death was not bathing or hot spring, but any combination of inadequate bathing, travel and staying. The maximum risk factor of bath death seemed to be ageing, and or the travel and staying seemed to become stronger stress for elders.
ABSTRACT
<b>Background</b>: Spring water exhibits “aging”, characterized by increased oxidation reduction potential (ORP) and diminished therapeutic efficacy. However, the influence of spring water ORP on the body during bathing is unknown. Gout has been treated by spa bathing and by acupuncture, as well as pharmacologically. We accordingly examined the relationship between ORP and uric acid excretion, and that between ORP and ryodoraku current, which is closely related to acupuncture.<br><b>Design</b>: Three groups of three volunteers each bathed in a different solution; sulphur-containing spring water, bicarbonate-containing spring water, or tap water. Serial changes in uric acid excretion and ryodoraku were measured.<br><b>Results</b>: Urinary uric acid: creatinine ratio and ryodoraku current increased after sulphur spring water bathing and diminished after tap water bathing. Urinary ORP was negatively correlated with urinary uric acid: creatinine ratio and urinary pH. Ryodoraku current and urine ORP changed in opposite directions.<br><b>Conclusion</b>: Bathing water ORP affected urinary ORP, urinary uric acid excretion, and ryodoraku current. Urinary ORP was assumed to reflect interstitial fluid ORP, suggesting that uric acid excretion and ryodoraku current were affected by interstitial fluid ORP. These findings appeared to indicate that ORP influenced cell membrane potential because voltage-dependent transporters or channels exist in the kidney and epidermis. Moreover, as urinary ORP was negatively correlated with urinary pH, ORP seemed to electrically buffer pH. As these findings can be explained by the Nernst equation by which ORP is derived, ORP of spring water might electrically influence the organism during bathing.
ABSTRACT
Purpose It has been reported that the excretion of urinary uric acid is increased by the ingestion of bicarbonated salt spring water or bathing in radioactive spring water. Furthermore, uric acid is considered to play an important role in diminishing oxidative stresses. We therefore investigated the influence of bathing water on the excretion of uric acid from the aspect of urinary oxidation-reduction potential (ORP).<br>Methods 1. Nine volunteers (three males and six females) aged 22 to 26 were divided into three bathing groups: in sulphur spring water, in bicarbonated salt spring water, and in tap water. Urine specimens were taken six times from 0600 to 1600 while repeating bathing and taking meals alternatively at intervals of 2 hours. ORP, pH, and the concentrations of uric acid and creatinine in urine specimens were measured.<br>2. ORP, pH, and the concentrations of uric acid and creatinine were measured in the urine specimens taken from the seven subjects in the bicarbonated salt spring and sulphur spring bathing groups early in the morning everyday during the stay at the spa. In addition, serum uric acid levels were measured at the beginning and the end of the stay.<br>Results 1. The average ORP was 527mV in tap water, 407mV in bicarbonated salt spring, and 145mV in sulphur spring bathing. The urinary ORP increased obviously after bathing in tap water and decreased after bathing in sulfur spring water. The average urinary ORP was 257mV after bathing in tap water, 220mV after bathing in bicarbonated salt spring water, and 216mV after bathing in sulfur spring water. Urinary uric acid/creatinine ratio showed a significant and negative correlation with urinary ORP in all three kinds of water. Urinary pH after bathing varied randomly. Urinary uric acid/creatinine ratio exhibited a significant positive correlation with the urinary pH in all three kinds of water.<br>2. While serum uric acid elevated after a short stay at the spa of less than 10 days, it decreased after a long stay of more than 2 weeks.<br>Discussion and Conclusions Urinary ORP immediately reflected the ORP of bathing water. The urinary uric acid/creatinine ratio possessed a negative correlation with urinary ORP. Because the ORP of spring water is commonly lower than that of tap water, bathing in spring water may increase the excretion of uric acid and as a result, may lower the serum uric acid levels after the long stay at the spa. The urinary uric acid/creatinine ratio exhibited a significant positive correlation with urinary pH. The results suggest that if the urinary pH gradually becomes alkaline after a long period of ingestion of alkaline spring water, the excretion of uric acid will be promoted, resulting in a lowered serum uric acid.
ABSTRACT
Drinking of hot spring water containing sulfur or sodium bicarbonate is reported to be beneficial for diabetic patients. In the present study, sulfur spring water and water from simple thermals were chosen to examine their effects on glucose metabolism. Eleven volunteers including eight type 2 diabetic patients and three healthy subjects drank hot spring water from Kawayu Onsen (K-O, acid alum vitriol hydrogen-sulfide springs, pH1.98), and another six patients from Asukano-yu (A-Y, alkaline simple thermals, pH8.9). Oral glucose tolerance test (OGTT) was performed after drinking tap water (200<i>ml</i>) or K-O spring water (5 times diluted) at a week interval (short term effect). Increments in plasma glucose levels were significantly lower (p<0.05) with predrinking of spring water than those with pre-drinking of tap water. To know the long term effect of drinking, patients drank K-O water twice daily for 4 weeks or A-Y water twice daily for a week. Hemoglobin A<sub>1C</sub> levels decreased significantly (p<0.05) by drinking K-O water and the levels of 1.5-Anhydro-D-glucitol increased by A-Y water (NS). From these findings, it is suggested that drinking hot spring water from K-O and A-Y is beneficial for diabetic patients if they have no contraindications for drinking these kinds of spring water.
ABSTRACT
One hundred and seven cases of sudden death in bathtubs, bath-death, were reviewed from the records of inquest by the Naruko Office of Miyagi Prefectural Police from 1984 to 1997. Eighty-four cases were of visitors staying at hot-spring hotels and 33 cases were of local residents. The number of cases of local residents increased by 1.8 times in the latter 7 years as compared with that of the first 7 years of the period investigated, probably because of aging of the population. The annual number of bath-death cases among visitors varied on a large cycle of over 10 years, seemingly in correlation with business conditions because it showed a strong correlation with the official discount rate. The average mortality rate of visitors was much higher than that of residents in the best business conditions and lowered to the same level as that of residents in the worst business conditions. One reason for such changes in mortality rate may be that while a majority of trips in the best business conditions were for pleasure, sometimes accompanying fatigue and stress of aged members including 85% or more of male, as business conditions became worse, the purposes of trips changed into recuperation and sightseeing. The number of bath-death cases among visitors increased every April and December, probably because of social customs such as new fiscal year parties, year-end parties, and so on. Bath-death cases occurred more frequently among those over 70 years, and were seen more at midnight, in winter, after drinking, at a bath temperature over 40 degree centigrade, and for a large temperature difference between the room and bath. Sixty-six percent of the bath-death cases were caused by cardiovascular diseases; 23%, by cerebrovascular events; and 11%, by other accidents.