The purpose of this study was to examine the value of maximal oxygen intake per kilogram body weight (VO₂maxlwt) recommended for women between 20 and 29 years of age by the Ministry of Public Welfare. The subjects were 199 female college students, who were not in the habit of drinking and smoking. Results obtained were as follows : After controlling the effects of age and percent body fat (%fat), VO₂max/wt showed a significant correlations with %fat, high-density lipoprotein choresterol and systolic blood pressure. The values of VO₂max/wt corresponding to borderline values of these CHD risk factors ranged from 27.6 to 29.5ml/kg ' min. The highest value of VO₂max/wt was very close to the value recommended for women older than 60 years of age by the Ministry of Public Welf are. The subjects were then divided into 4 groups ; at above and below the value of V02max/wt (35ml/kg ' min) recommended for women between 20 and 29 years of age, and at above and below the value of VO₂max/wt (3lml/kg ' min) recommended for women older than 60 years of age by the Ministry of Public Welfare. There were no significant differences among 4 groups in occurrence of abnormal values in CHD risk factors. The results of this study support the validity of the value of VO₂max/wt (3lml/kg ' min) recommended for women older than 60years of age by the Ministry of Public Welfare. However, it seems that it is not neccesary to recommend the value of VO₂max/wt (35ml/kg ' min) for women between 20 and 29 years of age, who were not in the habit of drinking and smoking.

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We studied the effects of stimulation frequency on the energy metabolism of rat skeletal muscles during electrical low-frequency stimulation, using in vivo phosphorus-31 magnetic resonance spectroscopy. The sciatic nerve of Wistar-Kyoto rats (n=16) was stimulated electrically using low frequency stimulation (LFS) at 30 Hz and high frequency stimulation (HFS) at 100 Hz as tetanizing frequencies. The initial tension during LFS was significantly different from that during HFS, 200.49:1:19.47 vs. 516.67i5.38 dynes (mean±S.E. ; n=8) (p 0.01). In the first 2 min of stimulation, the ratio of phosphocreatine (PCr) to inorganic phosphate (Pi) + sugar phosphate (SP) during LFS and HFS were 0.28i:0.04 and 0.53:i:0.06 (mean±S.E. ; n=8), respectively. Subsequently, the ratio during LFS remained lower than that during HFS. The intracellular pH during LFS and HFS in the first 2 min of stimulation was 6.27d:0.02 and 6.75±0.03 (mean±S.E. ; n=8), respectively. From 2 min to 12 min of stimulation, the intracellular pH during LFS remained lower than that during HFS. The results showed that lower levels of both energy and intracellular pH of skeletal muscles were maintained during LFS than during HFS, facilitating aerobic glycolysis to produce ATP during stimulation.

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The purpose of this study was to compare the Ratings of Perceived Exertion (RPE) in children while swimming at different temperatures. Five healthy male swimmers, aged 10 to 12, swam tethered using the breaststroke at 32°C, 25°C and 20°C water temperature in a flume, and biked at 25iC air temperature in contrast with swimming. In swimming, the resistance started at 1.0 kg and increased in 1.0 kg increments up to the point of exhaustion, and In bicycling, started at 0.5 kp with 60 rpm and increased in 0.5 kp increments, respectively. The subjects swam or biked for 5 min during each period, with a rest of 10 to 20 min until they had returned to their resting HR Ievel. The last exercise intensity was for 5 min with the maximal weight the subjects could support. The last min of Vo₂ and 30 sec of HR were measured during each exercise period. The subjects gave their RPE assessment at the end of each exercise. The relationships between %Vo₂max and HR were linear with a high correlation coefficient (r=0.995-0.998) in both water and air. However, the slope of the %Vo₂max-HR Iine tended to shift to the right in colder water. Increased Vo₂ of swimming in cold water was largely attributed to shivering. The RPE increased exponentially against %Vo₂max in both water and air and deviated more from linearity against HR. The RPE in 25°C water was lowest at all submaximal swimming. At maximal swimming, however, the RPE in the four conditions were much the same. It seemed that the RPE responded differently from HR in varying water temperatures.

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To investigate the effect of body temperature decrease which occurred along with cold exposure and menstrual cycle on visual acuity, the dark adaptation curve (DAO, heart rate (HR) and tympanic membrane temperature (Tty) were measured at thermoneutral (29°C) and cold (15°C) in both follicular and luteal phases {n menstrual cycle. Tty at thermoneutral and cold exposure in follicular phase were significantly lower than those in luteal phase. The degree of decrease in Tty by cooling in follicular phase was not significantly larger than that in luteal phase. HR was decreased significantly by cooling in both phases, while the difference between the two phases was not significant. DAC during cold exposure was lower than that during thermoneutral condition in both phases. Furthermore, the curve obtained during cooling in follicular phase was lower than that during cooling in luteal phase. However, DAC obtained by a subject who showed an increase of Tty by cold exposure in both phases was higher than that at thermoneutral. Even in thermoneutral in luteal phase, DAC during head cooling was significantly lower than that during thermoneutral. These results suggest that the brightness sensitivity in scotopic vision might be increased by a decrease of body temperature and the light threshold during dark adaptation threshold may be related to the change of Tty.

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To investigate the effects of body temperature decrease which occurred along with cold exposure and menstrual cycle, on color sensation, differential limen (DL) and points of subjectively equality (PSE) of red, green, blue and gray colors were measured by using metheds of limit in six young female subjects. also, the subjectively preferred complexion was selected. The lowest value in tympanic membrane temperature (Tty) was observed under the cold exposure condition at 15°C in follicular phase. DL of gray obtained during cooling was significantly lower than that during thermoneutral condition in follicular phase. However, DL of green, red and blue were not changed by cold exposure in both menstrual phases. The Munsell value of subjectively preferred complexion selected during cooling was significantly lower than that obtained during thermoneutmal condition in follicular phase. Compared with the distribution of Munsell hue of chips selected as preferred complexion in thermoneutral condition, the hue selected in cooling was not shifted to a more reddish one. These results suggest the possibility that brightness sensation rather than color sensation might be increased due to Tty decrease.

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Bathig in bed (BB) is an essential nursing technique applied to patients with restricted physical abilities. The aim of this technique is to keep the functions of the skin as an external barrier and to prevent the patients from infection and decubitus. However, the effect of BB on the blood circulation of the skin has not yet been identified, and the data observed are controversial. We have evaluated the effects of BB on the blood circulation of the skin by use of thermography. BB was applied on the right side of the back (RB) in 6 healthy female subjects who exposed both sides of their back (RB and LB) at room temperature. Ethanol was applied on the 5 x 5 cm area of RB and LB after BB, and recovery of the skin temperature was observed. After BB, the average temperature of RB was significantly lower than that of LB. This shows that BB decreases temperature of the skin exposed in the air probably due to the supply of water by washcloth. Recovery of the skin temperature after the ethanol-loading was accelerated on RB. This indicates that BB facilitates the response of the blood vessels in the skin.

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