All four Traditional Medicines of China, India, Tibet and Islamic countries have skillful and holistic approaches to mental, spiritual and physical health. Although they are ancient, they have the potential of becoming models for future life science.

Footbath is a safe and easy thermal therapy, however, it may cause stress on our body depending on the temperature. Temperature dependent changes of stress biomarkers in the saliva or urine, and of R-R variability by footbath were studied, and mechanism of effects and side effects were discussed.
Subjects were 14 healthy adult females (32±6 yeas old). The experiments started after permission of the Ethical Committee of International Research Center for Traditional Medicine. They took footbath at 38, 40, 42°C and control study after providing informed consents. They took footbath after 10min rest in a sitting position. Each footbath was 30min long, followed by 10min rest. The same subject participated in the studies four times at the same time of day before lunch. These experiments were in a random order four days apart each other except menstruation periods. Their ECG R-R variability and their concentration of salivary IgA and urinary 8 (OH) dG/creatinin were measured before and after footbath. The autonomic nervous balance was estimated from FFT analysis of the R-R variability; LF (0.04-0.15Hz) and HF (0.15-0.40Hz).
The results indicated that at 40 and 42°C their autonomic nervous balance estimated from LF/HF or HF power changed to sympathetic predominance. At 38, 40 and 42°C, salivary IgA increased significantly, and at 40 and 42°C, urinary 8 (OH) dG/creatinin increased significantly, while no significant change occurred in the control study.
These results indicated footbath for 30min at 40 and 42°C induced sympathetic predominance and caused oxidative stress. It was reported that oxidative stress induced activation of platelet aggregation. The oxidative stress as well as sympathetic activation may be related with the causes of the accidents during hot bathing as well as with the effects of thermal therapy. Further investigations are worth being performed.

Footbath have long been used for primary health care or for nursing, however, few researches have been reported. We intended to make footbath a safe physiotherapy or care technique in the modern medicine by more profound researches on footbath. The effect of footbath on the gastric motility was studied because footbath may promote recovery from post-surgical gastric paresis. The effects of footbath on the gastric motility and subjective hunger sensation were monitored in 14 healthy adult females (32±6 yeas old). They signed informed consents and took footbaths at 38, 40, 42°C and control footbath (by a footbath machine). The experiments started after permission of the Ethical Committee of International Research Center for Traditional Medicine.
They took footbath after 10-min rest in a sitting position. Each footbath was 30 min long, followed by 10-min rest. The same subject participated in the studies four times at the same time of the day before taking lunch (10:00-14:00). These experiments were in a random order four days apart each other except menstruation periods. Their blood pressure, ECG R-R variability and electro-gastrogram (EGG) were monitored. The subjective hunger sensation was asked before, during and after footbath. The autonomic nervous balance was estimated from FFT analysis of the R-R variability. LF (0.04-0.15Hz) and HF (0.15-0.40Hz) components of the R-R variability were calculated. EGG was also analysed by means of FFT to calculate amplitude and frequency. The results showed the amplitude and frequency of EGG increased depending on temperature. However, the correlation between HF power of R-R variability and amplitude of EGG showed negative correlation. Regarding hunger sensation, more cases felt hunger in 38, 40°C than in control. At 42°C, the amplitude and frequency were apparently higher than in other temperatures, while the hungry cases were less than in 38 or 40°C. These discrepancies may be caused by the artifact due to sweating on the abdominal EGG leads, considering high b wave of EEG at 42°C.
In conclusion, it was indicated that footbath may promote gastric motility and induce hunger sensation at 38-40°C in healthy volunteers.

Temperature dependent systematic circulatory changes by the pure thermal action were studied by means of footbath, which can neglect hydrostatic pressure and buoyancy. 14 healthy adult females (32±6 yeas old) took footbath at 38, 40, 42°C and control footbath after providing the written informed consent. The experiments started corthe permission of protocol of this experiment by the Ethical Committee of International Research Center for Traditional Medicine. They took footbath after 10 minutes' rest in a sitting position. Each footbath was 30 minutes long, followed by 10 minutes' rest. The same subject participated in the studies four times at the same time of the day before lunch. These experiments were in a random order four days apart each other except during menstruation periods. Their systemic circulatory changes and autonomic nervous balance calculated from FFT analysis of the R-R variability were monitored by the automatic sphygmomanometer, impedance cardiography and ECG, and their cerebral circulatory changes were monitored by the Near Infrared Spectroscopy (NIRS) and the Transcranial Doppler (TCD), and skin circulation was measured by the thermographic changes of the face and hand. Their subjective comfort was assessed by the face scale every 5 minutes. The results showed that their cardiac output and blood pressure increased, and tissue blood flow of the M. Trapezius and the skin temperature of both hand and face increased in temperature dependent manner. Simultaneously LF/HF or HF power changed depending on the temperature. Regarding cerebral circulation, total blood volume of the surface of the frontal lobe was suspected to be increased, however, elevation of PI values indicated an increase of the intracranial pressure. The same systemic and autonomic nervous changes of footbath were reported in full body bath. Considering the subjective comfort, the appropriate duration of footbath for healthy persons may be 20-25min at 38°C, 15min at 40°C, 10min at 42°C. Circulatory activation by footbath may support the clinical utility of footbath for the safe care of aged people who may be drawn in bath tub. High PI value at 42°C footbath which means high intracranial pressure may cause the accidents during lethal hot bathing.

We studied temperature-dependent effects of the footbath on heart rate variability, EEG (F3, F4, P3, P4 of 10/20 international method), cerebral circulation, and subjective comfort, using electrocardiography (ECG), electroencephalography (EEG), near-infrared spectroscopy (NIRS), transcranial Doppler (TCD) and face scale. Subjects were 14 healthy adult women (32±6 years old) who took 3 types of footbath (10cm below the knee at 38°C, 40°C, and 42°C) and the control sitting position without footbath in a randomized sequence after providing written informed consent. Their ECG, EEG, NIRS on the forehead, and TCD findings for the middle cerebral artery were monitored for 50min including a 30min footbath. Subjective changes were monitored every 5min using the face scale. LF (low frequency; 0.04-0.15Hz) and HF (high frequency; 0.15-0.4Hz) components and Lorenz plots parameters were obtained from ECG R-R variability. EEG power and EEG right-left coherence were also calculated.
At 42°C footbath, total hemoglobin (Hb) concentration of the forehead, LF/HF ratio, Pulsatility Index (PI: a marker of intracranial circulation and intracranial pressure obtained from TCD), and parietal β₁ wave power increased significantly. HF power and EEG coherence of θ and α₁ wave of the parietal and frontal leads decreased significantly with decline of comfort. At 40°C, cerebral circulation, LF/HF and PI changed less, but EEG power of the frontal α₁ and α₂, and parietal β₁ waves increased significantly after the cessation of footbath with simultaneous increase of comfort. At 38°C, transient but significant decrease of PI value after footbath was associated with significant increase of EEG power of the frontal θ and parietal α₂ waves after footbath. Parameters having statistically significant correlation with subjective comfort were HF power, Lorenz plots parameters, EEG power and coherence, and frontal Oxy Hb (r=0.150-0.231, p<0.0001 by Spearman's method). The EEG power of frontal α₁ waves had the largest correlation coefficient with subjective comfort (r=0.231, p<0.0001).
It was assumed that temperature-dependent changes of autonomic nervous activity and cerebral circulation caused changes of EEG and comfort during footbath. It was indicated that frontal α₁ wave power of EEG and Lorenz plots parameters obtained from R-R variability may be usable as indices of comfort in hot bathing.

One of the methods of external treatment is herbal bathing. We studied the usefulness of herbal bathing by investigating the physiological and biochemical changes that occurred during whole-body herbal bathing.
Eleven healthy adult males (36±9 years old) were subjected to two types of bathing, herbal bathing and plain water bathing, at an interval of four or more days at random sequence after giving written informed consents. Physiological and biochemical changes were monitored 10min before bathing, 10min during herbal bathing in the sitting position, and up to 60min after bathing.
The results showed that the skin temperature of the face (forehead) and hands decreased at a slower rate, fluctuations of the blood pressure were smaller, and the peripheral vascular resistance decreased more faster in herbal bathing than in plain water bathing. These results suggest that herbal bathing is more effective in maintaining peripheral skin temperature, stimulates peripheral circulations, and suppresses excessive fluctuations of blood pressure better than in plain water bathing. Analysis of the autonomic nervous activity by ECG R-R variability showed that the parasympathetic tone was more predominant in the herbal bathing than in plain water bathing, supporting the result showing a larger relaxing effect in herbal bathing. Although there was no significant difference between herbal bathing and plain water bathing in terms of changes in the total blood volume of the Musculus Trapezius, the increase in the total blood volume of the forehead was greater in herbal bathing than in plain water bathing. These results suggested that the herbal bathing might be able to increase the blood volume of the frontal lobe.
These differences of the physiological changes between herbal bathing and plain water bathing indicated that the herbal bathing may stimulate the circulation in the frontal lobe as well as the skeletal muscles. These results supported the health-promoting effects of herbal bathing.

Carbon dioxide (CO₂)-enriched water, one of the Japanese pharmacopeias, has been used as an alternative thermotherapy to treat the intractable diabetic skin diseases. However, few scientific researches on the physiological effects of CO₂-enriched footbath have been reported. Fifteen males (aged 22-52, 31±10) took part in this study after providing their written informed consents. They took three kinds of footbath (plain water, CO₂-enriched water and control without water) at 38°C for 30min in random sequence. Their core temperature from oral and tympanic membrane, cutaneous blood flow, tissue hemoglobin concentration at the cerebral frontal cortex and trapezoid muscle, systemic blood pressure, heart rate variability, salivary IgA, comfortable feeling with face scale were measured before, during and after footbath. CO₂-enriched footbath showed significant physiological effects on the systemic and peripheral circulation. Local (under water) cutaneous blood flow, and tissue blood flow of the frontal cortex were significantly higher than in the plain water footbath. The systolic and diastolic blood pressure and heart rate in CO₂-enriched footbath were also lower than those in the plain water footbath. Heart rate variability of CO₂-enriched footbath showed an decrease of LF/HF ratio and more HF/(LF+HF) ratio than that of plain water footbath. These parameters indicated lesser stress for the heart in CO₂-enriced footbath than in the plain water footbath. The relaxing effect of CO₂-enriched footbath was also indicated from the results of face scale and salivary IgA concentration. All of these results supported that the CO₂-enriched footbath was less stressful and more relaxing, and had more physiological effects on the local systemic and cerebral circulatory system and autonomic nervous system than plain water footbath.

Balneotherapy includes several modalities of treatments and wellness programs, such as physiological and pharmacological effects of hot spring bathing and aqua-exercise, relaxing and biorhythm adjusting effects of staying in the urban climates and educational instruction for healthier life style. We examined health promoting effects of the comprehensive balneotherapy as a whole by the randomized controlled study. 89 women, who had no medical care, and were aged 40-65 years (mean +/- SD age: 59.0 +/- 8.0 years), volunteered for this investigation. Subjects were assigned at random to three groups; group 1 was the control group without any intervention; group 2 with exercise for 60min and educational guidance; group 3 with exercise for 30min and balneotherapy including aquaexercise for 30min and bathing in hot spring for 30min in addition to educational guidance. Each group followed the prescribed program twice a week for 3 months. There was no significant difference in age, body mass index (BMI), blood pressure, heart rate, %FAT, diet/exercise custom and psychological conditions among the three groups. Before and after the program, the physiological, biochemical and psychological measurements were performed: body weight, blood pressure, heart rate, physical strength using ergometer, serum lipids, liver function and questionnaires with profile of mood state (POMS) and self relating depression scale (SDS). After excluding 4 subjects who were dropped out because of their convenience, the results were compared. In group 2 (N=28) and 3 (N=28), body weight, BMI, blood pressure and heart rate were significantly decreased and their physical strength and psychological condition were improved significantly (p<0.05). Furthermore only in group 3, serum total cholesterol, atherogenic index and triglyceride were significantly decreased (p<0.05). The difference between these two groups was not due to changing of their diet and estimated energy consumption by daily activities during 3 months. These data suggest the efficacy of balneotherapy with hot spring bathing and aqua-exercise for health promotion.

 Physiological changes induced by the localized bathing of hands, feet, and simultaneous hand-foot baths were studied and compared with each other in order to elucidate the physiological mechanism of hand and foot baths. Fifteen healthy adult males (32±10years old) took hand, foot, and simultaneous hand-foot carbonated (module mixture type artificial carbonated bath, at a CO₂, concentration of 1,100±100 ppm, pH 4.8) and freshwater baths (pH 7.4) at 38°C, and assumed a control sitting position following a randomized controlled design. They took 7 kinds of localized baths mentioned above at 1-week intervals. Each localized bathing session involved a 5-minute rest in a sitting position, the 30-minute bathing, followed by a 10-minute rest. Subjects’physiological parameters, such as the heart rate, blood pressure, near infrared spectroscopy of the forehead, laser Doppler flowmetric findings for immersed (foot) and non-immersed (shoulder muscle) body surface capillary fiow, as well as the body temperature of sublingual and tympanic membranes were monitored.
 While no physiological changes occurred during the proximal 5-10 minutes after starting simultaneous hand-foot baths, the body temperature, cerebral tissue circulation, cutaneous blood flow of the non-bathed skin, and heart rate increased and the diastolic pressure decreased in the distal half of 30-minute carbonated and freshwater baths. These physiological changes would probably be due to the thermal effect.
 However, the proximal 5-10 minutes after staning hand and foot carbonated baths showed opposite autonomic changes, which disappeared in the simultaneous hand-foot carbonated baths. Freshwater localized hand and foot baths did not lead to such differences. The cutaneous blood flow of bathed skin of the hands and feet was also significantly different only in the carbonated baths, while no differences were obtained in the freshwater hand and foot baths.
 Taken together, 38 °C and 1,100 ppm carbonated localized baths (hands and feet) showed opposing heart rate variability just after staning bathing, and they induced different cutaneous blood flow changes during bathing. These physiological differences in hand and foot bathing may be due to somato-autonomic and axonal refiexes induced by skin nociceptive ion channels with different sensitivities and reactions due to the varying pH of the bathing medium, and due to different hydrostatic pressures of the hand and foot baths.