Our previous experimental results have shown that a mixture of thiamin, arginine, caffeine and citric acid (TACC) has an enhancement effect on fat metabolism in mice and human. In this study we examined the effect of tea ingestion, which was supplemented with TACC, on energy expenditure during a rest and an exercise period from the viewpoint of fat metabolism (utilization) in healthy subjects. A single-blind, placebo-controlled, crossover study was carried out to compare the energy expenditure after ingestion of TACC-supplemented tea (thiamin, arginine, caffeine, and citric acid; 1.1, 1240, 52, and 540mg, respectively) or control tea on two consecutive days, in 10 healthy male and female subjects (aged 21-27y) in experiment 1. After the tea ingestion, subjects sat on a chair for 30 min followed by treadmill walking (5km/hr) for 30 min. Respiratory quotient (RQ) and oxygen consumption (VO2) were measured during rest and exercise periods. A double-blind, placebo-controlled, crossover study was performed in 14 healthy female subjects (aged 21-22y) in experiment 2, of which study design was the same as that of experiment 1 except for an additional measurement of RQ and VO2 before ingestion of the tea for 30 min in the sitting position. As results, total energy expenditure and fat oxidation were similar between the two cases (ingestion of control tea and TACC-tea) during the rest period after tea ingestion both in experiment 1 and experiment 2. On the contrary, treadmill walking resulted in about three-fold increase in total energy expenditure; however, fat oxidation during the exercise was significantly greater in the case of TACC-tea than in the control tea case in the both experiments. This effect of TACC-supplementation, enhanced fat oxidation and energy expenditure, seemed to be positively proportional to subjects' Body Mass Index.

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The present study compared the color discrimination ability of elderly subjects to that of young people. We measured the ability of young people to discriminate colors using a portable device and a 100 hue test and then ascertained age-induced changes in color discrimination ability by comparing the respective abilities of elderly and young people to discriminate colors. The results of the present study showed that, when compared to young people, the total deviation score for the elderly was greater, while the color discrimination ability was inferior. Only in the elderly, did the total deviation score correlate to the chronologic age and visual acuity. The average deviation score for all hues was higher for the elderly. The deviation score for the blue/green (BG) and purple (P) hues was high for the young people, while that for the red/purple (RP) and blue/green (BG) hues was high for the elderly. Analysis of difference of the average deviation score for all hues showed a significant difference in 88 of the 100 hues These findings of this study suggest that some hues are difficult to discriminate regardless of age, while some hues become more difficult to discriminate with age. We believe that age-related reduction in color discrimination ability is affected by factors such as visual acuity, and yellowing of the lens and cataract.

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The purpose of this study was to clarify the strategy of postural control in frontal plane occurred by lateral shifting of center of gravity, and furthermore to reveal related factors of postural strategy in elderly subjects. Healthy 18 elders and 11 young students participated in this study. Subjects achieved the task which was to shift their center of gravity to maximal lateral position. We measured 2-dimensional position of acromion and ante-superior iliac spine (ASIS) in frontal plane. The maximal torques of dorsi / plantar flexion and medial / lateral rotation of ankle were standardized by % body weight (%BW) and used for evaluation of muscler forces of lower leg. According to the results of kinematic measurements of acromion and ASIS, we classified elders in Hip strategy (HS) group (n=13) and Ankle strategy (AS) group (n=5). We employed statistical analysis to compare these HS, AS, and young groups. Result of multi regression analysis of lateral shift of ASIS showed that the significant factors were inferior shift of Acromion for HS (R2=0.638, p<0.01, r=-0.799), and lateral shift of Acromion and plantar flexion torque for young group (R2=0.433, p<0.03, r=0.658). In conclusion, postural strategy with lateral transition of body weight in elders was namely Hip strategy which was controlled with moving mass of pelvic girdle as a counter mass of scapulary movement. However, a part of elderly subjects seemed to have same strategy to young subjects. Therefore studies with multiple view point including sensory system and brain functions will be needed for the future study.

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To obtain basic data for designing easy to understand and memorize auditory signals, we examined the functionary imagery and onomatopoeic representations associated with periodic frequency-modulated (FM) tones. When the modulation wave was rectangular and the modulation rate was slower than 5Hz, FM tones were associated with the imagery of alarm and were represented by repeatedly prolonged syllables. When the modulation rate was 15 to 30Hz, FM tones evoked the functional imagery of calling and the onomatopoeic representation of repeated flapping. These results showed that the functional imagery and onomatopoeic representation of FM tones varied as a function of modulation rate.

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The purpose of this study was to examine if physiological and psychological responses would vary when the power output was maintained during repetition exercise. Healthy male subjects (n=8) performed ten sprint-sets including 10-s maximal pedaling followed consecutive active [170-s, 0 kilopond 60 revolutions per minute (rpm)] and passive recovery [180-s, on cycle ergometer]. Integrated electromyography (IEMG) and mean power frequency (MPF) of using the data of the EMG from vastus lateralis during 10-s maximal pedaling were determined. IEMG was divided by mean rpm exerted during 10-s maximal pedaling to give average rectified value (ARV). Maximal power output (MaxP) and mean power output (MeanP) during 10-s maximal pedaling remained unchanged from 1st to 10th set. Three parameters [arousal, concentration and motivation] of visual analog scale (VAS) were used for evaluating psychological response. The three parameters did not change. Blood lactate concentration (La) significantly increased (P<0.05). The ARV significantly decreased (P<0.05) whereas the MPF significantly increased (P<0.05). Therefore, it is concluded that physiological parameters changed in the repetition exercise established in the present study.

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