The purpose of this study is to examine the effects of ankle plantar and dorsal flexion on the rating of perceived exertion (RPE) in pedaling. Seven healthy men performed two kinds of ankle movement pattern, which took neutral position (NP) and dorsal flexion position (DP) in the crank top dead center. Heart rate, Vo 2, joint movement, joint torque, joint power and crank torque were measured. The electric goniometer was attached to the ankle outside in order to feed back the ankle angle, and the practice was carried out. Two kinds of pedaling were carried out for every 4 minutes by turns succeeding 12 minutes warm-up exercise by incremental loading. Consequently, although NP and DP did not have the significant difference in HR and Vo 2, RPE in NP was significantly lower than in DP. Two factors were considered as a reason of the difference; (1) the hip extension torque at the down stroke was larger, (2) there were few work on lower extremities' in NP.

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This paper examines the effects of the menstrual cycle, meaning premenstruation, menstruation, and follicular phase, on two kinds of experimental tasks, and symptoms associated with menstruation. The results showed that the total number of task and reaction time for simple reaction tasks tended to be influenced by the effect of the menstrual cycle phase. Moreover, task performance in the follicular phase tended to be higher than in the other two phases. However, there was no effect of the menstrual cycle phase on task performance for responses to circumstances task. Physical changes developed during menstruation and psychological changes during premenstruation. However, the results of this paper were obtained from limited data because there were seven subjects.

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“Reaching”, the movement involved in straightening the arm toward a particular target, has been studied from various points of view. The present study considered how to divide the component of movement into ballistic and corrective movements. Utilizing the devised method, it was examined the relationship between the initial movement, the change in the ratio of the component of movement, and the results in a task involving the direct manipulation of a pen-tablet interface.
The results confirmed that the relationships between both the initial velocity and the ratio of the ballistic-corrective movement (MT_C/MT_B), and between the ratio of the ballistic-corrective movement and the movement's accuracy did not depend on the experimental condition. Moreover, these ratios were very stable. As well, constant tendency was confirmed in the relationship between the initial velocity and the task's result. However, a difference was seen in the latter regarding differences in experimental conditions. Therefore, the baseline parameters of each task condition should be established preliminarily.
In conclusion, it could be suggested that the accuracy of a manipulation task's performance could be predicted by the initial movement.

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Toes and soles of feet have an important role to keep stability in standing posture and to perform the bipedal locomotion. The purpose of this study is to develop a toes grasping strength meter, then to examine age-related changes and the relationship between the toes grasping strength and postural control performance. A remodeled Smedley's dynamometer was fixed on a panel and an adjustable ankle holder was set on the panel to measure the toes grasping strength. At first, we examined the reproducibility of the measuring method and the correlation coefficient of two separate measures was 0.973. Then we measured toes grip strength of 97 male and female subjects aged 20 to 84 with the measurement of grip strength, postural sway, foot-balance, functional reach and time of 10m walk. The results showed that the toes grasping strength was related to age and declined by ageing faster than grip strength. The toes grasping strength had significant correlation coefficients with grip strength, foot-balance with eyes open, functional reach and the time of 10m walk but had no correlation with postural sway. It was suggested that the toes grasping strength related to the function of postural control at standing position, especially the tolerance to falling forward, and it can be applied to the prevention of falling accidents of the elderly.

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This paper's purpose is to investigate experimentally whether eye blinks act as index of cognitive anxiety or not. It is required for usability evaluation to examine not only effectiveness and efficiency but cognitive anxiety which is related to the degree of satisfaction. In this experiment, subjects' task was to search for the target word in the structure of hierarchical menu. Previous studies have shown that eye blinks are clearly affected by task difficulty. In this study, task difficulty was not varied as independent variable. It was judged with response protocol whether cognitive anxiety occurred or not. When subjects were left in the trial-and-error situations, it was assumed that they would be cognitively anxious. Blink rates under “trial-and-error” state were significantly higher than under “understanding” of error-free state. This result shows that the increase of blink rates was affected not by task difficulty but cognitive anxiety. Eye blinks were thus confirmed to be valid as an index of cognitive anxiety.

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The purpose of this study was to obtain basic data about the effect of high heels on female posture. A substitute wooden heel of varying heights was used in the experiment.
Two groups of ten healthy adult women (young and middle-aged) were analyzed. Postural movement for four different heel heights (subsequently referred to as O- control, L- low, M- medium and H- high) was measured for sixty seconds each. The main results are as follows:
(1) Regarding the average velocity of postural movement, age was found to be the leading determining factor. The variances for age and heel height were 60% and 13% respectively.
(2) Based on a frequency analysis, a test to illustrate the significance for average differential values for O and L, M, H was carried out. X showed a significant decrease in the high frequency band. This indicates that, as women get older, there is a marked loss of recovery power for lateral direction. For Y, the younger group displayed greater control than the middle-aged group in all frequency bands for M and H.
(3) For middle-aged subjects, the burden of heel height is marked for both X and Y in the high frequency band (5.0-10.0Hz).
(4) Because of the relative level of stability of low heels for the middle-aged group, it is recommended that heel height be chosen taking into account both purpose and safety.
(5) This research shows that frequency analysis is an effective tool for evaluating standing posture.

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