To investigate precisely the fluid shifts associated with water drinking in humans, we measured continuously blood density and plasma electrolyte concentrations using the mechanical oscillator technique and ion-selective electrodes, respectively, in healthy young volunteers before (10 min) and after (48 min) water drinking for a period of 2 min. Beat-by-beat blood pressure was also monitored throughout the experiment. Drinking 1 l tap water caused a transient increase in blood density immediately after the drinking episode (from 1051.1+/-0.5 g/l before drinking to 1051.8+/-0.5 g/l 4 min after the start of drinking, P<0.05), followed by a gradual reduction (1050.1+/-0.5 g/l at 31 min). This drinking-induced change paralleled those of haematocrit, plasma density and plasma volume. Plasma [Na+] and [Cl-] and osmolality decreased after drinking without transient increases and reached minima at about 30 min. A transient increase in mean arterial blood pressure was observed prior to the increase in blood density. These findings suggest that water drinking causes a biphasic change in plasma volume: initial haemoconcentration, probably due to sympathetic acceleration, followed by haemodilution due to the post-absorptive effect, and further suggest that the fluid shift associated with the initial haemoconcentration is isosmotic.

We conclude that exercise-trained females have a high incidence of orthostatic intolerance during LBNP, with a greater reduction of SV independent of changes in baroreflex and neurohumoral function. A lower incidence of LBNP intolerance in UT may be accounted for by a lower reduction of SV during LBNP. An increase in leg compliance in the exercise-trained females may play an important role in inducing pronounced reduction of SV and hence the intolerance to LBNP.

An aging society with a declining birthrate has become a problem in Japan and China, making it impor tant to favor improving lifestyles over increasing life expectancy. University students majoring in sports science can become leaders in improving the health of these nations.Participants included 98 Japanese and 76 Chinese male university students from Fukuoka and Inner Mongolia, respectively. An anonymous questionnaire was administered in July and March 2015 to examine whether their lifestyle was healthy.In addition, we compared Japanese and Chinese textbooks on health and physical education and examined the health education contents.Based on breakfast, smoking, and drinking habits, the Japanese students had a more desirable lifestyle than the Chinese ones; 10.2% 10/98 of the Japanese students were smokers, while 52.6% 40/76 of the Chinese students smoked. Based on their daily bedtime and sleeping habits, the Chinese students had a more desirable lifestyle than the Japanese students.We found that the Japanese students scored an average of 25 points on the Rosenberg Self-Esteem Scale, while the Chinese students scored about 30 points, which is similar to the findings from a previous study.Health education is featured twice as much as physical education in Japanese textbooks for junior high and high school students. Students learned about "smoking and health" in the fifth and sixth grades, junior high, and high school.While practical skills of physical education account for most pages, the Chinese textbooks have about a quarter of the pages compared to the Japanese ones on health education for junior high school students. There was no description about lifestylerelated diseases and prevention, such as smoking. The Chinese textbooks of physical ［資 料］Vol. No.