Changes in blood lactic acid density after 10 minutes of 80% VO₂max. bicycle exercise due to bathing in CO₂ water obtained from a newly developed CO₂ water generator (MCH-C80: Maeda Iron Works Co., Ltd.) were compared with changes due to bathing in plain water. The blood lactic acid density increased from 1.6mmol/l to 9.3mmol/l due to the exercise load, but decreased to 3.3mmol/l after 10 minutes of CO₂ water bathing at 38°C and further decreased to 1.9mmol/l after 30 minutes. In the group bathing in plain water, blood lactic acid density decreased to 4.0mmol/l immediately after bathing and to 2.3mmol/l after 30 minutes. The difference in results between the CO₂ water bathing group and plain water groups was significant (p<0.05). No bad effects of CO₂ water bathing were observed. Thus, CO₂ water obtained from this CO₂ water obtained from this CO₂ water generator is useful for enhancing the effect of bathing on recovery from fatigue.

The thermotherapeutic effects of bathing with CO₂ water obtained from a newly developed CO₂ water supply system was studied in comparison with bathing with plain water. After 10min bathing at 39°C, dermal blood flow in the upper arm region was higher in the group bathing with CO₂ water than in that bathing with plain water (p<0.05).
Further, the skin temperature lowering in the forehead region after bathing was slower in the group bathing with CO₂ water than in that bathing with plain water. The subjective sense of being heated and sense of comfort during and after bathing were also higher in the group bathing with CO₂ water. No side effects were found. It is therefore suggested that the CO₂ water obtained from this system is useful for enhancing the thermotherapeutic effect of bathing.

Viability of C. trachomatis in thermal waters collected from 5 spas was examined by inclusion forming ability in HeLa cells. In the acid springs (pH 2.0-2.2), the organisms lost their infectivity within 0.5hr when they were incubated at 37°C and no inclusion were detected when incubated at 42°C. In weak alkaline springs (pH 8.0-8.8), the organisms could be detected after incubation at 37°C for 2hr or at 42°C for 1hr, but number of inclusions were significantly decreased.

Viability of Pseudomonas aeruginosa was examined by putting it into hot spring collected from seven places. In the acid waters (pH 2.0 to 2.2), the organisms lost their viability immediately at both cultivation temperatures of 37°C and 42°C. In alkaline waters (pH 8.0 to 9.1), the organisms were detected and increased after cultivation for 2 hours at 37°C.
The above result suggests that Pseudomonas aeruginosa may be present in whirlpools and/or indoor swimming pools of alkaline waters having a large number of bathers in a relatively small volume of water.

The Ministry of Health and Welfare inaugurated an official recognition system for spa-based health promotion facilities in 1988 as part of its health promotion program. As a result, those facilities gradually increased across the country until the number of the recognized facilities reached 17 by February 1995.
The Japan Health & Research Institute has performed factfinding surveys on the use of these recognized spa-based health promotion facilities every year from the beginning of the recognition system. This paper reports the survey results obtained during these 5 years.
During the past 5 years, 275 males and 138 females used these spa-based health promotion facilities (with tax deductions applied to madical expenses). The number of male patients was about twice as large as that of female patients. Most males used the facilities because of diseases in the field of internal medicine, and most females, because of diseases in the field of orthopedic surgery.
We are planning to prepare a manual for evaluating the effects of spa therapy and assess the efficacy of spa therapy by including a new survey item of “clinical effects of spa therapy” in a questionnaire for a nationwide survey.

In this study, 10 healthy students were subjected to experiments. They bathed in plain hot spring water and hot spring water with 2% Togol mud at 39°C for 10min at an interval of 1 week. No difference in the change rates of pulse rate and blood pressure was observed between the two types of bathing. Forehead and oral temperatures decreased slightly after bathing in plain hot spring water. However, after bathing in hot spring water with Togol mud, the forehead temperature tended to be higher than that before bathing while the oral temperature increased significantly after bathing. Skin surface temperatures on the chest wall, left instep, and right forearm increased significantly after both types of bathing. Changes in the skin temperature after bathing in hot spring water with Togol mud tended to be greater than those after bathing in plain hot spring water. Eight out of 10 students felt warmer after bathing in hot spring water with Togol mud. These findings suggest that bathing in hot spring water with Togol mud is useful for medical care.