Spa bathing at night has been thought to improve sleeping conditions and symptoms of dementia such as restlessness, wandering, and aggression in patients in our nursing home with special needs for the aged. The present study investigated patient activity using a lifestyle measurement device (Kenz Lifecorder) to examine the effects of night bathing on senile dementia by more objective methods. Nine patients with senile dementia of the Alzheimer type staying in health facility for the elderly were studied. These patients' symptoms of dementia were already incurable but daily living activities somewhat remained. The patients were divided into a night bathing group (n=5) and daytime bathing group (n=4) to study patient activity using a Kenz Lifecorder for 14 weeks, that is one week before the start of bathing, 12 weeks with bathing, and 1 week after bathing. The night bathing group had a higher rate of activity than the daytime bathing group. When comparing the daytime of night bathing patients with the daytime bathing individually, the former displayed increased activity in the daytime. As a group, the night bathing group was found to show a significant increase in the amount of daytime activity. However, the statistical significance was reached after Weeks 9-10, so 2-3 months were required to change lifestyle rhythms. The authors hope that night bathing or night bathing assistance will be received favorably by the long-term care and health care insurance systems.

The purpose of this study was to eliminate factors of accidents during Japanese style bathing of the elderly.
We investigated the age-related changes in cardiovascular and thermoregulatory function in response to the bathing at 40°C. We measured the blood pressure and the heart rate using an automatic spygmomanometer, the skin blood flow at the forearm using laser Doppler flowmetry, the tympanic temperature using a thermistor, and the sweat rate at dorsum manus using the ventilated capsule method during bathing at 40°C for 20min in 10 aged (73.5±8.4, mean±SD) and 10 young subjects (19.8±1.8).
Aged subjects failed to maintain a stable blood pressure during the immersion in the bathtub. While the heart rate during the bathing significantly changed in the young subjects, no change was observed in the aged subjects. Skin blood flow, tympanic temperature, and sweat rate increased during the bathing for both in the aged and the young subjects, though with smaller changes among aged subjects.
These findings suggest that the adaptability of cardiovascular and thermoregulatory functions to heating and hydrostatic pressure during Japanese style bathing decreases with age.

This study examined the effect of hot-spring bathing (40 to 41°C) on salivary secretion and salivary secretory IgA (sIgA) in healthy volunteers. Ten volunteers (10 men, average 33.6±9.3 years old) bathed in a hot-spring for 10 minutes.
Saliva samples were collected before bathing, during bathing (from 5 to 7 min), and after bathing using the Saxon test. The saliva flow rates and sIgA concentration were determined and then the sIgA secretion rates were calculated.
The saliva flow rates increased significantly during the bathing (p<0.02) and decreased after bathing. The sIgA secretion rates during bathing were significantly higher than those before and after bathing (p<0.02).
The increases in saliva flow rates and sIgA secretion rates during bathing were considered to indicate the improvement of local immunity in the oral cavity and thus considered to be useful for preventing upper respiratory tract infections.

The purpose of this study was to clarify difference in heating effect of the two types of bathing for the elderly, footbathing at 44°C and full bathing at 40°C.
The subjects of this study were nine elderly persons for footbathing (average 73.5 years old) and 10 elderly persons for full bathing (average 77.4 years old). The tympanic temperature was measured using a thermistor, sweat rate using the ventral capsule method, and blood pressure and heart rate using an autonomic spygmomanometer during control period 10 minutes before bathing, for 20 minutes during bathing, and for 10 minutes after bathing. Subjects wore plain clothes while taking a footbath time or swimming trunks while taking a full bathing. The ambient temperature was set to 20°C during the footbath or 26°C during the full bathing.
During the footbath, the tympanic temperature increased to 60% that of full bathing and a significant increase of sweat rate was observed. In contrast, during full bathing, a significant rise in systolic blood pressure was observed immediately after bathing started due to hydrostatic pressure and a significant drop of diastolic pressure was observed after bathing due to heating during bathing.
These findings suggest that the footbath is safe, does not cause any change in blood pressure and is expected to provide mild warming for the elderly.

The purpose of this study was to clarify effects of foot bathing at 44°C for the patients with hemiplegia. The subjects of this study were six patients with hemiplegia (average 71.6 years old) and six healthy volunteers (average 74.3 years old). Blood pressure and heart rate were measured using an autonomic spygmomanometer, tympanic temperature using a thermistor, and sweat rate using the ventrilated capsule method during the control period of 10 minutes before foot bathing, for 20 minutes during foot bathing, and for 10 minutes after foot bathing. Subjects wore a plain clothes while taking a footbath and the ambient temperature was set to 20°C. During foot bathing, heart rate was significantly increased, but blood pressure and pressure-rate product did not changed. Tympanic temperature was no significant changed in both subjects during foot bathing. But a significant increase of sweat rate was observed in patients. In healthy volunteers, in contrast, skin blood flow on the bottom of the foot was significant increased. These findings suggest that regulation system of cardiovascular is slightly declined in the patient, and patient's thermoregulatory system was difficult in healthy humans.

The purpose of this study was to clarify the effects of ingesting spa water on electrogastrography and heart rate variability in humans. The subjects were eight youths (average age 22.3 years old). We measured three and six circles per minute (cpm) power of electrogastrography (EGG), the high-frequency (HF: 0.15-0.4Hz) components, and the ratio of low-frequency (LF: 0.04-0.15Hz) components to HF components in heart rate variability (HRV) during 90 minutes. We also assessed the taste of water, pain or abnormalities in the stomach by questionnaire. The subjects ingested the spa water or purified water after thirty minutes, and ingested no water on a different day. The six cpm power of EGG, presumably reflecting instestinal activity, was significantly increased with spa water ingestion. The three cpm power of EGG, presumably reflecting stomach activity, did not change under any conditions. The HF components in HRV, presumably reflecting cardiac parasympathetic activity, tended to increase with ingestion of spa water. The ratio of LF to HF components in HRV, presumably reflecting cardiac sympathetic activity, significantly decreased with ingestion of spa and purified water. There was no difference in the answers of the questionnaire. These findings suggest that spa water ingestion activates instestinal activity, increasing parasympathetic nerve activity and suppressing sympathetic nerve activity in humans.