The purpose of this study was to investigate the effect of pubertal maturation determined by years after menarche on bone metabolism. The subjects were 45 healthy girls of the first-year in a junior high school. Stiffness of the right calcaneus was measured by quantitative ultrasound (Lunar, A-1000). Urinary deoxypyridinoline (DPD), as a marker of bone resortrtion and serum bone alkaline phosphatase (BAP), as a marker of bone formation were measured. The bone metabolic markers (DPD, BAP) showed high levels before menarche, whereas Stiffness increased one or more years after menarche. These results suggested that there would be time lag for one or more years between acceleration of bone turnover and increase in Stiffness. Exercise and sufficient nutrition in this period of bone mineral accumulation would be effective in increasing peak bone mass.

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Although a self-report questionnaire has already been developed to evaluate maximal oxygen uptake (Vo_2max) indirectly, it is still unclear whether it can accurately predict Vo_2max, especially in middle-aged and older adults. The purpose of this study was to compare differences between directly measured Vo_2max using a cycle ergometer protocol and Vo_2max predicted by a self-report questionnaire. One hundred forty subjects (aged 61.3±8.2) were divided into four groups: control group (group C, n=33), walking group (group W, n=37), trekking group (group T, n=44) and jogging group (group J, n=26). Vo_2max was measured following an incremental protocol using a Monark cycle ergometer (measured Vo_2max) and by a self-report questionnaire (predicted Vo_2max). Pearson correlation coefficients between measured Vo_2max and predicted Vo_2max were significant in all groups. However, standard errors of estimation (SEE) of group J were higher than those reported in previous studies. The difference in measured Vo_2max and predicted Vo_2max correlated significantly with the mean between the measured and predicted Vo_2max in group J. There were significant differences between the measured Vo_2max and the predicted Vo_2max in groups T and J. These results suggest that when the exercise intensity is high, such as in jogging, and consequently when Vo_2max is high, the self-report questionnaire method might underestimate Vo_2max.

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Since intestinal motility has circadian rhythms as well as sleep-wake cycles, it is possible that there are some relationships between functions of the gastrointestinal tract, especially intestinal motility, and sleep health. However, little is known about the relationships between intestinal motility and sleep health. Therefore, the relationships among functional constipation (FC), irritable bowel syndrome (IBS) and sleep health in the population of middle aged women living in the Tokyo metropolitan area were investigated using the self-reported questionnaire. FC and IBS were defined by the Rome diagnostic criteria for the functional gastrointestinal disorders (Rome II). As a result, both the sleep health in FC and in IBS were significantly worse than in control, and there was a tendency for the sleep health in IBS to be worse compared with that in FC. Accordingly, these results suggest that there are relationships between conditions of intestinal motility, namely bowel habits, and sleep health. In order to improve sleep disturbance coming into question in recent years, the consideration of bowel habits also seems to be important.

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Although it was expected that body water turnover (WT) changes with growth, the extent of these changes is not clear. This study compared body water turnover between children and young men. Six children (6.0±2.6yr) and eight young men (21.1±1.4yr) participated in this study. Total body water and body water turnover were measured using the deuterium (D_2O) dilution technique. A urine sample was obtained every day for 10 days after oral administration of D_2O. The day-by-day concentrations were used to calculate the biological half-life of D_2O and body water turnover. Biological half-life of D_2O was significantly shorter in children than in young men (5.17±0.87 days vs. 7.66±0.93 days, P<0.05), and percentage of body water turnover was significantly higher in children than in young men (13.69±1.98 % vs. 9.17±1.08 %, P<0.05). Body water turnover, expressed quantitatively, was also greater in children than in young men (88.3±15.2 ml/kg/day vs. 56.3±83ml/kg/day, P<0.05). These results indicate that children have a higher body water turnover than young men, and suggest that body water turnover drastically decreases with growth.

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This study focused on thermal radiation from the shoulders. Two types of experiments were carried out at an ambient temperature of 19℃. : one using Japanese style of bedding with a partition, the other using a European style bedding with a headboard. The partitions and headboards were examined while covered with eight different types of metal or plywood. Termal reflectivity was measured with a spectrophotometer, and the angle factor for the partitions and headboards with a solid projection camera. Surface temperatures, heat flows, net radiation, air velocities and ambient temperatures were also measured. The results were as follows: 1)The influence of thermal reflectivity of material is easily reflected when the distance from the partition or headboard to the shoulders is short. 2)The heat emission from the shoulders is low when thermal reflectivity of materials is high. 3)The thermal radiation from the shoulders is low when a pillow is used.

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