In this study, data on walking speed, step numbers, cadence of natural walking were collected and their relations to foot wear, clothing, Iuggage carried and time of the day as well as crowdedness were investigated. This survey was held in Shinjuku, Tokyo in 1991. Six thousand three hundred and seventy nine walking people were observed from 10 : 00 am to 5 : 00 pm. Ten students who were trained to observe the walking were employed for the data collection. The observed subjects were divided into three age groups, name{y young (less than 30 years), middle (31-60years) and elder (over 6lyears), and their age groups were decided by the students based on their appearance. For the analysis, they were further classified into male and female groups. The factors which affect walking speed, step number and cadence were taken into consideration. It was found that young people were more sensitive to their factors in their natural walking and old people showeci lower flexibility to these factors.

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The purpose of the present study was to evaluate cardiac sympathetic (SNS) and parasympathic (PNS) nervous system activities during isometric continuous and intermittent handgrip with power spectrum analysis of heart rate variability (HRV). Eight healthy men performed work at 10% maximum voluntary contraction. The sequence of tests included three different work patterns : 1) the continuous handgrip for 30 min, 2) the intermittent handgrip (10 sec contraction +5 sec relaxation) for 45 min, 3) the intermittent handgrip (10 sec contraction +10 sec relaxation) for 60 min. These experiments were performed at two different heat loads (25°C and 40°C, R.H. 50%). To evaluate HRV, low frequency component (0.03-0.15Hz : LFP) and high frequency component (0.15-0.5Hz : HFP) power were calculated. The SNS and PNS activities were evaluated by LFP/HFP and HFP/(HFP+LFP), respectively. Summary of the results was shown below. 1) The change of the SNS and PNS activities were not significant among the different work patterns, due to the lower work load in the present experiment. 2) The increase of HR at 25°C was mediated primarily by the decrease of the PNS activities during the work periods. 3) The effects of heat loads on the SNS and PNS activities were significant. Briefly, at the same work pattern, the SNS activities at 40°C were higher than those at 25°C, but the PNS activities at 40°C were lower than those at 25°C.

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The effects of a 15-wk aerobic conditioning (4.2±1.3 dlwk) plus energy restriction (25 kcal/ kgld diet) program on anthropometric and physiologic attributes were studied in 16 obese women between the ages of 18 and 24. The women were divided into either an experimental (E, n=10) group or a control (C, n=6) group. The exercise+diet (E) group demonstrated significant reductions in body weight, both absolute and relative body fat, Katsura index, and serum triglycerides, and increases in oxygen uptake relative to lactate threshold (LT), maximal oxygen uptake, and the ratio of high-density lipoprotein cholesterol to total cholesterol. In the C group, none of the variables measured in this study remained unchanged. Thus the benefits of weight reduction without any change in fat free weight following the program were pronounced in the female university-age group that we studied. In conclusion, the highly structured aerobic conditioning at intensities correspondlng to LT together with a proper dietary regimen is considered optimal with respect to favorable changes in various anthropometric and physiologic attributes. The feasibility of treating obese individuals with manifestation of medical and/or psychological problems in a school setting should be a significant matter in future research.

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The physiological responses and the magnitude of perceived fatigue (MPF) were estimated from eight healthy men during isometric continuous and intermittent handgrip at 10% maximum voluntary contraction (MVO. The physiological responses involved electromyogram (EMG), heart rate (HR), mean blood pressure (MBP) and forearm blood flow during contraction (FBFO and relaxation (FBFR). The sequence of tests included three different work patterns : 1) continuous handgrip for 30 min, 2) intermittent handgrip (10 sec contraction +5 sec relaxation) for 45 min, 3) intermittent handgrip (10 sec contraction +10 sec relaxation) for 60 min. These experiments were performed on two different heat loads (25°C and 40°C, H.R. 50%). The results were as follows : 1) The localized muscle fatigue in the forearm was observed during the work periods. 2) The mean frequency of EMG was higher at 40°C than 25°C. 3) FBFR was significantly lower than FBFC at 40°C. 4) MPF and MBP were little influenced by the heat load. 5) MPF correlated well with both HR and MBP.

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Time- and voltage-dependent interaction of antiarrhythmic agents with target cardiac ion channels is termed the modulated receptor hypothesis. Actuaily class I agents suppress the maximum upstroke rate (V_max) of intracellular potential (V_ic) depending on the pacing cycle length (PCL) and external potassium concentration ([K⁺]_e). We examined this concept from the aspect of interstitial potential (V_is), since V_is reflects the second time derivative of V_ic. V_ic. and V_is were recorded sequentially using standard microelectrode applied to the paced and superfused guinea pig papillary muscles. In the steady state, the greatest negative deflection of V_is (V_min) was suppressed by qumldine (10 μM) In both PCL and [K⁺]_e-dependent manner just like V_max. However, quinidine-induced greater inhibition of V_min than V_max was evident at shorter PCL and greater [K⁺]_e. Based on the sequential alteration of PCL and exposure to ouabain (10 μM), different quinidine sensitivity between V_min and V_max is most likely accounted for by the activity-dependent K⁺ efflux and Na⁺-K⁺ pump-mediated K⁺ uptake (i. e., [K⁺]_e fluctuation). Thus, the modulated receptor hypothesis is concluded to be valid in terms of V_is.

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The purpose of this study was to clarify the effect of the level of spinal cord injury (SCI) and of daily exercise on the relationship between heart rate (HR) and oxygen uptake (Vo₂) in persons with SCI (PSCI) during an arm cranking exercise. Eighteen PSCI were divided into three groups according to the level of SCI ; 4 quadriplegics (C6-C8), 7 high- Ievel paraplegics (T3-T8), and 7 low-level paraplegics (T10-L2). In the relationship between HR and Vo₂, the higher the level of SCI, the smaller the slope of regression line, that means the HR at a given Vo₂ become larger as level of SCI was higher. Significant differences were found among these regression lines (P 0.01). In addition, the regression lines between HR and Vo₂ in active persons tended to shift toward upper in comparion with those in Inactive persons. The present investigation clearly shows that the HR-Vo₂ relationship in PSCI is remarkably influenced by the level SCI and physical training.

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The responses of electroencephalogram (EEG) to different odors and their densities were studied on four men and two women at rest while sitting. The odors examined were citrus, floral and lavender, and their densities were 100 ppb and 200 ppb. The odors were released for ten minutes from a duct to fill the room completely. The subjective estimation indicated that citrus had a tendency to be the most comfortable odor in this study, but it was not significant. To evaluate changes of EEG, the power spectra of frequency-fluctuation of awave (Fz) and the rate of α, β and β/αwave (Oz, Fz) were calculated. The rate of awave (Oz) in the period of giving out the citrus at 100 ppb was significantly (p0.05) higher than that of the lavender. The rate of β wave (Oz) in the period of giving out the floral at 200 ppb was significantly (p 0.05) higher than that of the lavender. The regression coefficient of the power spectra of frequency-fluctuation of α wave in the period of giving out the lavender at 100 ppb was significantly higher than those in the other periods of the experiment. The regression coefficient of the power spectra of frequency-fluctuation of α wave for lavender given out at 200 ppb was significantly (p0.01) higher than those for the other odors given out. It seems that the regression coefficient of the power spectra of frequency-fluctuation of α wave can be used for the evaluation of psychophysiological responses.

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The purpose of the present study was to investigate sexual differences in relationships among percent body fat (%Fat), waist-to-hip ratio (WHR), waist-to-stature ratio (WSR), abdominal circumference to stature ratio (ASR), body mass Index (BMI) and skinfold thicknesses in healthy male and female adults. Subjects were 64 males and 65 females, aged 22-60. Body density was measured by under \vater weighing and by skinfold anthropometry. Mean %Fat was 15.6% in males and 23.9% in females. Mean WHR was 0.83 in males and 0.72 in females. The correlation between %Fat and WHR was not significant in females (r= -0.l04) but was significant in males (r= 0.631, p 0.001). Highly significant correlations were obtained among %Fat, WSR, ASR, BMI, and sum of eight skinfolds in both sexes.

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Pitch-matching experiments were conducted to clarify the pitch determlnation process of complex FM-AM tones which consist of components whose frequency and amplitude are simultaneously modulated. The pitch is higher' when FM and AM of each component are in phase than when they are out of phase. The pitch shift induced by the phase difference between FM and AM of each component becomes larger as its relative power increases. These experimental results suggest that the pitch of complex FM-AM tones is determined as follows : A complex FM-AM tone is resolved into each FM-AM component by the auditory filter bank. The spectral pitch of each FM-Alvl component is determined by a loudnessweighted pitch averaging processes. The central pattern recognizer determines the pitch of complex FM-AM tones by integration of virtual pitches derived from the spectral pitches.

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