The influences of monochromatic light were studied through measurement of EEG (Fz, Cz, Pz), ECG, blood pressure, pupil diameter, oral temperature, and subjective evaluation. The experiment employed ten young males (23±2.9yrs) with normal color perception. Three monochromatic light conditions were transmitted through three types of filter to produce three different wavelenghts (458 nm, 550 nm, 670 nm). The main effect of monochromatic light and the exposure time on EEG in Fz and Pz was significant. The alpha wave ratio was apparently lower in the 458-nm wavelength than in the other wavelengths (550 nm, 670 nm). The interaction between the light condition and the time was significant in pupil diameter. At 11 minutes of light exposure, pupil diameter in the 458-nm and the 550-nm wavelength light was obviously smaller than that in the 670-nm wavelength light. Moreover, at 19 minutes of exposure, pupil diameter in the 458-nm and the 550-nm wavelength light was significantly smaller than that in the 670-nm wavelength light. In conclusion, we estimated that arousal level increased during the exposure to 458-nm wavelength light. The effect of 458-nm wavelength light on the arousal level and pupillary reaction might be similar to the spectral sensitivity based on melatonin suppression described in recent studies. Therefore, this finding may support recent understanding of a non-visual system including the intrinsic photosensitive retinal ganglion cell (ipRGC).

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This study investigated to clarify physiological responses during level nordic walking (NW) and downhill nordic walking (DNW) and downhill walking (DW). Seven healthy subjects (4 females and 3 males), aged 20 - 43, were participated in this study as a subject. They performed four treadmill walking tests, i.e. one incremental exhaustion test measuring maximal oxygen uptake (V02max), and three 10 min walking tests. The 10 min walking tests were performed at 60m/min in NW DNW and DW, respectively. Downhill grade was 16% during DNW and DW. Oxygen and DNW were significantly higher than those of DW (p<0.001). But there were no significant differences in NW and DNW. OMNI scale of the upper body of DNW and NW were significantly higher than that of DW (p<0.001). Additionally, OMNI scale of the upper and whole body during DNW were significantly higher than NW (p<0.01). On the contrary, OMNI scale of DNW was significantly lower than DW (p<0.05). Our results demonstrate that DNW on the treadmill induce to increase the intensity up to a similar level of NW. Additionally, it was suggested that metabolic rate of the upper body in DNW might be higher than in NW.

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To design a suitable hand-controlled joystick, it is necessary to study the sensory motor characteristics of the force and torque actively exerted by the hand. However, since the basic data is inadequately covered by research papers and databases, this study was performed based on actual operating postures. This paper focuses on the following points. 1) A comparison of the directional dependency of the minimum torque exerted by the dominant hand. 2) A verification of Weber's law, namely the ratio of the minimum torque to the prior load torque. To measure the torque exerted by a hand, a joystick capable of sensing six axes of force and torque was prepared and an experiment performed using 10 young males and 7 young felames as subjects. The results showed that, a) the minimum torque increases in accordance with the load torque in all directions, b) the minimum torque of the radial flexion is larger than that in the other directions, and c) Weber's ratio close to between approximately 0.1 and 0.15 as the load torque increases. The results suggest that the minimum exerted torque differs depending on the direction of application, and that Weber's law is applicable.

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To compare physiological changes by taking a shower between 6 preoperative patients and 7 healthy females, we examined energy metabolism, blood pressure, heart rates, and tympanic temperature before, and at 0 and 20 minutes after taking a shower. We analyzed the data by a repeated two-way ANOVA. All the individuals including patients and controls showed the same trends concerning physiological changes associated with shower taking. No significant differences were found in the four indices between the two groups. This study showed that influences of taking shower on physiological changes are comparable in healthy women and patients with gynecologic diseases who do not have either cardiovascular or respiratory complications.

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This study investigated the effects of short-term (3 months) exercise training on arterial stiffness, serum lipoprotein profiles and oxidized LDL levels in frail elderly people (11 males and 9 females, aged 71.0±9.9 years old). Training instruction was given and exercises were performed twice a week using ordinary machines designed for resistance training. Although there were no significant changes in arterial stiffness, serum TC, TG and HDL-C levels, the value of T-C/HDL-C in females, and serum MDA-LDL levels in all subjects were decreased after training (P<0.05). These results suggest that short-term exercise training could improve the risk factors for atherosclerosis in frail elderly people.

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The purpose of this study was to develop an overview of the physical fitness of Japanese people, ranging from the young to the elderly, based on data regarding the physical characteristics of workers obtained by the National Institute of Technology and Evaluation (NITE), and to assess the relationship between their physical fitness and extremity joint torque and between their physical fitness and lifestyle. The data used in this study were measurements of the physical fitness of 1000 Japanese workers between 2001 and 2002. The parameters measured were grip strength, vertical jump, trunk flexion seated, jump reaction time, single-leg standing time with eyes closed, and limb joint torque, and replies to a questionnaire on lifestyle and exercise history were also used. The results revealed two tendencies: a tendency for the single-standing time with eyes closed values to decrease steadily with age, and a tendency for the grip strength, vertical jump, and jump reaction time values to start decreasing at a particular generation (grip strength and jump reaction time: in there forties to sixties, vertical jump: in their forties to sixties, in both gender). In addition, multiple regression analyses were carried out on the relationship between age and physical fitness and between age and limb joint torque. The results showed that physical fitness except trunk flexion seated tended to be greatly affected by age, and that grip strength tended to be affected by maximum voluntary contraction of the upper limbs. The results of a multiple regression analysis of the responses to the lifestyle questionnaire and the subjects' physical fitness characteristics revealed that grip strength, trunk flexion seated, vertical jump, and single-leg standing time with eyes closed tended to be affected by lifestyle.

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