The effects of bathing with inorganic salts and carbon dioxide (ISCD) on body temperature, systemic circulation, food ingestion and absorption have been studied in healthy volunteers. The peripheral blood flow in the forearm was found to increase in and after immersion of the forearm into a 25l bathing receptacle containing ISCD, as compared with plain water. The peripheral blood flow tended to increase in a dose-dependent manner with ISCD bathing. The skin core temperature, the skin surface temperature and the peripheral blood flow were significantly higher after ISCD bathing than after plain water bathing. The influences of ISCD bathing on food ingestion and absorption were also studied in healthy volunteers. Blood glucose and insulin levels after food ingestion tended to be suppressed by ISCD bathing as compared with plain water bathing. There was no difference between ISCD and plain water bathing in total protein, total cholesterol, triglyceride, HDL cholesterol, and uric acid levels in the blood. These results suggest that ISCD bathing may contribute to the promotion of human health.

Introduction: The health-related QOL is important for an index to prescribe health condition, but there is little analysis that what kind of bathing method the person whom this index has good performs. In this study, health-related QOL and habitual bathing was intended to clarify relationship, correlation. Methods: The participants were 198 employees of a quasi-drug manufacturing company and their family members who could and cooperated in the present study. The study was conducted as a self-report survey from October 1-30, 2010, with questionnaires being distributed to and collected from subjects before and after this period. Participants were asked about their sex, age, bathing number of times in week, frequency of bath additive use in week, temperature of bathing, bathing duration, and water level when in the bath, health, and sleep quality. Health-Related Quality of Life was assessed using the Short-Form Health Survey (SF-36v2) , and self-rated health and quality of sleep were assessed using a Visual Analog Scale (VAS). Results: When I divided it at the average age concerning a bathing method and the age, there was much frequency of bathing per week in late debut as an entertainer 45 years old or older, and under 45 years old had a short bathing time, and water level when in the bath was shallow. The shallow tendency that water level when in the bath was observed in that level in female. Relationship SF-36v2 and bathing method, it was suggested that a Social functioning significantly (p<0.01) increases so that temperature of bathing was low, a Role physical significantly (p<0.05) increases so that there was much bathing number of times in week, a General health significantly (p<0.05) increases so that there was much frequency of use of bath additives per week. Each of subjective self-rated health, quality of sleep by VAS, it was good in conjunction with frequency of use of bath additives per week. Discussion: This study applied to an authorized company employee, and there was a limit that the external validity was weak, but was related to General health, social functioning, Role physical and bathing method. The influence of bathing habits such as full-bath bathing and the use of bath additives on a person’s physical and psychological state as found by our study can be regarded as a way of maintaining health among those in the prime of life. Because our study uses a cross-sectional design, interpretation had a limit, and it was thought that a prospective study would be necessary in future.

  Frequent bathtub bathing (BB) improves sleep quality and mental health of middle-aged and older Japanese individuals. This study investigated the chronic effects of BB with and without a bath additive (bathtub bathing with KIKIYU [BBK]) in healthy young adults. The study involved healthy young adults who habitually showered, as opposed to bathing. Nineteen participants were randomly assigned to either the BB or BBK groups for 14 consecutive nights. After a 2-week washout period (shower bathing), the participants were asked to switch their bathing styles (a crossover design). The artificial bath additive for the BBK group contained inorganic salts and carbon dioxide. The participants were evaluated by using the Oguri-Shirakawa-Azumi Sleep Inventory-Middle-aged version (OSA-MA) and 1-ch sleep electroencephalography (EEG) for sleep quality, the Profile of Mood States (POMS), Self-rating Depression Scale (SDS), and Apathy Scale (AS) for mental conditions.  Sleepiness on waking and refreshing scores in the OSA-MA significantly differed between the shower bathing and BBK groups. EEG results did not significantly differ among the bathing styles. Vigor T-score and total mood disturbance (TMD) scores showed significant differences in the two bathing groups (shower vs. bathing), and fatigue T-score was significantly lower in the BBK group compared with both the BB and shower groups. SDS score was significantly lower in the BBK group compared with the shower group. AS score was significantly lower in the two bathing groups (shower vs. bathing).   The OSA-MA score was possibly influenced by vasodilatation and circulation by using carbon dioxide and keeping the body warm after bathing by using inorganic salts. The OSA-MA score was possible also affected by fatigue alleviation and maintenance of vitality by using a citrus lemon scent and yellow-green hue. Furthermore, frequent body heating affects the central nervous function related to mood and emotion.  Based on these results, we can conclude that BB and BBK prior to shower bathing improved the mental health of the young adults in this study.

Background: Bathing is an important behavior for keeping the body clean and is one of the habits of daily life. Among other things, bathing is regarded as a means of relieving fatigue, refreshing oneself, benefiting health, and improving sleep. As such it can be considered a health-maintaining activity. Apart from a previous study by the authors, there has been very little research on the relationship between home bathing habits and health. Objective: The aim of this study was, therefore, to clarify how physical and mental health relate to daily bathing in the home, particularly the habit of full bath immersion. Method: The participants were 198 employees of a quasi-drug manufacturing company and their family members who could and cooperated in the present study. The study was conducted as a self-report survey from October 1-30, 2010, with questionnaires being distributed to and collected from subjects before and after this period. Participants were asked about their sex, age, frequency of bathing per week, frequency of use of bath additives per week, temperature of bath water, bathing duration, and water level when in the bath, health, and sleep quality. Health was assessed using the Profile of Mood States (POMS) inventory, and self-rated health and quality of sleep were assessed using a Visual Analog Scale (VAS). Results: Among bathing habits, the group with a high bath frequency had significantly low scores for tension-anxiety and depression-dejection mood scales, and significantly high self-rated health. In the present study, self-rated health and quality of sleep were significantly better in the group who frequently used bath additives. In the full bath group, Fatigue score was significantly low and self-rated health and quality of sleep scores were significantly high. Discussion and Conclusion: Taking a full bath frequently and frequent use of bath additives are bathing habits that increase physical and psychological health in the middle-aged.

Introduction: Some students take showers instead of baths for economic reasons or because they dislike cleaning the bathtub. The purpose of this study was to examine the effect of bathing routines on students’ working efficiency. Subjects: Seventeen (six male and 11 female) healthy young students (19.6 ± 0.7 years old, mean ± SD) who habitually took showers instead of baths participated in this study. Informed consent was obtained from all the subjects and the study was approved by the Ethics Committee of Kumamoto Health Science University. Method: Subjects were randomly assigned into two groups. The subjects in the first group (bathtub bathing [BB]) were immersed to the supraclavicular level in their home bathtub and instructed to rest for 10 minutes with the temperature regulated at 41°C. The subjects of the second group (whole-body warming after BB [BBW]) followed the same bathing protocol and then rested in a sleeping bag and sheet for 30 minutes to keep their bodies warm. Each period was carried out over 2 weeks in a cross-over design. Washout periods were 2 weeks long. The evaluation items of this study included the obstructive sleep apnea (OSA) sleep inventory MA version (OSA-MA), a questionnaire containing a visual analog scale (VAS) to judge the subjective bathing effect, profile of mood states, salivary stress marker (α-amylase), and the Purdue Pegboard test. These tests were evaluated before and after the BB sessions, BBW sessions, and washout interval for a total of four times in a 6-week period. Result: Participants tended to report a better sleep feeling on the OSA-MA after the BB or BBW sessions than after showering. There were significantly better changes in both the BB and BBW in the VAS for bathing effect in terms of “Sense of deep sleep,” “Body fatigue,” “Light feeling of the body” than after a shower. The mean α-amylase value in the saliva of the BBW group participants was significantly lower than that after showering. The mean Purdue Pegboard test scores of both the BB and BBW sessions were significantly higher than that after the shower. Discussion: Sleep quality seemed to be more improved after BB or BBW than after showering, perhaps due to reduced stress. Work efficiency also increased in the BB and BBW groups.

Purpose: We have previously reported the physiological and biochemical effects of bath salts. In this study, we used bath additive containing artificial carbon dioxide and sodium chloride (S bath additive), and the acute effects of bathing once with S bath additive and chronic effects of daily bathing with S bath additive for 15 consecutive days were compared with the effects of bathing once in plain water. Improvement in 10 symptoms was investigated using a 5-point verbal rating scale (VRS). Methods: Nine patients aged 51-82 years (mean, 66.6 years) with cold intolerance and lower leg pain were treated with balneotherapy. Whole-body bathing at 40°C was performed for 10 min daily (day 1, bathing in plain water; days 2-16, bathing with S bath additive). On days 1, 2, and 16, changes in patient’s subjective symptoms were evaluated using a VRS ranging from -1 to +3. Results: Compared with bathing once in plain water, bathing once with S bath additive was improvement of coldness, body warmth, blood circulation promotion, limb warmth, lightness of foot, and coldness in limbs. Daily bathing with S bath additive for 15 days significantly improved all symptoms compared with bathing in plain water. A comparison between single and daily bathing with S bath additive showed that relieving fatigue and lumbago were significantly improved after consecutive bathing, demonstrating the benefits of long-term usage. Discussion: Bathing once with S bath additive had acute effects on symptoms associated with peripheral circulation, such as coldness in limbs, body warmth, and limb warmth. Daily bathing with S bath additive improved bone- and joint-related symptoms, such as lumbago and shoulder stiffness, demonstrating that the chronic effects of S bath additive differ from the acute ones. These results are consistent with previous studies on natural hot springs which found that the efficacy of short-term treatment was distinct from that obtained after >2 weeks of treatment.

Objective: The purpose of this study was to examine the effects of bathtub bathing （BB） on sleep and working efficiency of healthy young adult students. Furthermore, the effects of BB and prolonged increased body temperature from the use of insulating sheets and sleeping bags after BB （warming after BB: BBW） on sleep and working efficiency were investigated. Subjects: Eighteen （six males, 12 females） healthy young students （19.6±0.7 years old, mean±SD） who habitually took showers instead of baths participated in this study. Informed consent was obtained from all of the subjects, and the study was approved by the Ethics Committee of Kumamoto Health Science University. Methods: Subjects were randomly assigned to two groups （n＝9 in each group）. The subjects in the BB group were immersed in their home bathtub to the supraclavicular level and instructed to rest for 10 min with the temperature regulated at 41°C. The subjects in the BBW group followed the same bathing protocol, and they then rested in a sleeping bag and sheet for 30 min in order to keep their bodies warm. The length of each study period was 2 weeks in a crossover design. After the 2-week-long washout periods, the subject groups were switched. The subjects were evaluated with the Oguri-Shirakawa-Azumi sleep inventory, MA version （OSA-MA）, which utilizes a visual analog scale （VAS） with which subjects rate their sleep when they wake up, and Purdue Pegboard Assembly test. These tests were employed before and after the BB and BBW sessions, resulting in four testing periods in the 6-week period. Results: Sleep rating on the OSA-MA was no significant difference in both the BB and BBW groups compared to ratings recorded after showering. The subjects in the BB and BBW groups had significantly increased VAS ratings for “Feeling of sound sleep,” “Refreshing,” and “Lightness of the body” compared to the ratings after showering. The mean Purdue Pegboard test scores of the subjects in both the BB and BBW groups were significantly higher than those recorded after showering. Discussion: Changing bathing style from shower to BB or BBW improved the working efficiency of students on the Purdue pegboard test. BB and BBW resulted in soothing effects owing to improvements in the subjects’ quality of sleep.

Objective: The purpose of this study was to clarify the chronic effects of bathtub bathing (BB), whole body warming after bathtub bathing (BBW), and bathtub bathing with herbal extracts (BBH) on the mental condition of healthy young persons. Subjects and Methods: Experiment 1: Eighteen (6 male and 12 female; age: 19.6±0.7 years, mean ± SD) healthy young persons who were taking a shower habitually but not bathtub bathing participated in this study.   From November 2012 to December 2012, subjects were randomly assigned into two groups (each 3 male, 6 female): those who had BB or 30-min BBW 14 times for 14 consecutive nights during a 2-week period. After a 2-week washout period, subjects were asked to switch their bathing conditions (a cross-over design). Experiment 2: Twenty (8 male and 12 female; age: 21.3±1.6 years, mean ± SD) healthy young persons who were taking a shower habitually but not bathtub bathing participated in this study.   From October 2013 to November 2013, subejects (4male and 6 female) were randomly assigned to undergo BB or BBH.   The herbal extract contained Dong dang gui (Japanese Angelica Root), Chimpi (Citrus Unshiu peel), Chamomilla recutita, and ginger extracts.   After a 2-week washout period, subjects were asked switch to the other bathing condition (a cross-over design).   All participants provided informed consent for participation in these studies, and these studies were approved by the Ethics Committee of the Kumamoto Health Science University.   The subjects immersed their bodies up to the supraclavian for 10 min, in tap water adjusted to a temperature of 41 °C in their bathtub at home. The subjects’ mental conditions were assessed using Profile of Mood States short version questionnaire.   The differences in the effect of BB and BBW, as well as those of BB and BBH on the subjects’ mental conditions and their mental conditions pre-BB and post-BB, pre-BBW and post-BBW, pre-BBH and post-BBH were analyzed using Wilcoxon’s signed-rank sum test. Results: The points for depression-dejection, fatigue, and confusion in those who had BBH significantly converged to the median average (50 points) compared to the points in those who had BB.   The points for anger-hostility before BBW and BBH significantly converged to the median average (50 points) after BBW and BBH, and there were no significant differences in points before and after BB. Conclusions: The subjects’ anger-hostility was influenced by body warming in BBW and the vasodilatory components of the herbal extracts.   The subjects’ depression-dejection and fatigue was influenced by the fragrance and color of herbal extracts.

 The effects of bathing in a solution of artificial bath additive including inorganic salts and carbon dioxide (CO2-bathing: 41°C, 10 minutes; the concentration of carbon dioxide was 160-180 ppm, and that of inorganic salts was about 64 ppm) on the cardiovascular system, body flexibility, muscle stiffness and the subjective feeling of bathing were compared with those of no bathing and plain water bathing in the healthy subjects.  The deep body temperature and skin blood flow increased after bathing, and the increases after CO2-bathing were significantly greater than those after plain water bathing. Body flexibility after CO2-bathing was similar to that of no bathing and plain water bathing.  Stiffness of the trapezius muscle was decreased at both 15 min and 30 min after CO2-bathing and plain water bathing, with no change in no bathing. The changes at 15 min after CO2-bathing and plain water bathing were statistically significant. Stiffness in the latissimus dorsi muscle decreased at both 15 min and 30 min after CO2-bathing and plain water bathing, with no change in no bathing. However, only these changes at 15 min and 30 min after CO2-bathing were statistically significant.  A large decrease in the stiffness of the trapezius muscle by its isometric contraction was observed during both CO2-bathing and plain water bathing, and the decrease after CO2-bathing was greater than that after plain water bathing. These changes did not reach statistical significance.  Improvements in subjective feeling of bathing were observed after both plain water bathing and CO2-bathing. Improvements after CO2-bathing in stiffness of muscle, ease of movements and mental relaxation were statistically greater than those after plain water bathing.  Compared with plain water bathing, CO2-bathing showed additional effects on muscle stiffness and subjective feeling of bathing. Further research is needed to confirm the effectiveness of the CO2-bathing alone and combined with isometric movements on muscle stiffness.