The authors compared the gait dynamics between elderly and young people in conjunction with integrated electromyogram analysis in order to create basic guidelines pertaining to designing effective stumbling-resistant socks. The targeted leg joints were the joints of the knees, toes, and ankle. Through motion analysis, the authors compiled gait cycle curves for the angles, angular velocity, and angular acceleration of each joint. Upon examining these curves, the authors extracted features that expressed gait dynamics. The differences (ΔS) between the maximum and the minimum values were extracted. Characteristic features of gait in the elderly were observed in the joints of the ankles, rather than in the joints of the knees or the toes. A positive correlation was observed between the stride lengths and the ΔS of angular velocity of the ankle joints: elderly people with small ΔS values had shorter strides. Furthermore, the main agonist muscles used during gait were not identified through the electromyogram. By contrast, elderly people with larger ΔS values had longer strides, and the tibialis anterior and the gastrocnemius medial head were found to be the main agonist muscles. These findings suggest that ΔS of the angular velocity of the ankle joints may be a useful index in designing stumbling-resistant socks.

In order to design brassieres (bras) which effectively control breast vibration, the vibration of breasts was measured using high speed cameras during walking，running and jumping. The subjects consisted of eight young females with different sizes of breasts. By measuring skin viscoelasticity and compression of the breast, their relationships were compared with the breast vibration. The following results were obtained: 1. The breasts showed characteristics of vibration locus on the x,z plane during walking, running and jumping. The bigger the breast the greater the vertical amplitude of vibration; 2.A time lag between the movement of the breast and the body was shown on the z plane due to the inertial influence; 3. The average of amplitude, speed and acceleration of outside measuring points are greater than inside measuring points during walking, running and jumping, so that it is important to control the vibration of the outside breast during exercise. 4. The breast size has a high correlation with the average of amplitude and speed in both vertical and horizontal direction during walking or running, and those in vertical direction only during jumping. The average amplitude exhibits a positive correlation with the recovery rate of skin and a negative correlation with the compression stress ratio F10mm during running which showed that the softer the breast, the greater the vibration.

The temperature and humidity in a room equipped with a large-scale dishwashing machine are frequently high. The purpose of this investigation is to elucidate the influence of wearing a conventional dishwashing apron in terms of thermal stress to the body. Five healthy women with a mean age of 61.6 years old performed a 45 min tableware washing task wearing a conventional dishwashing apron or waterproof clothes (control). The authors measured subjective fatigue, salivary alpha-amylase and oral temperature before/during (30 min and 45 min after the onset of the task) and 15 min after the task. All measured variables increased during the task, and were not different between the conditions during the task. The oral temperature 15 min after the task was not different from that of before the task in the control condition with waterproof clothes, while the oral temperature remained higher in the condition with the conventional dishwashing apron. This suggests that the waterproof clothes reduce the labor burden of the tableware washing task compared to a conventional dishwashing apron.

To make clear the effect of age, body features and type of brassiere on the comfort from the view point of control of breast vibration and reduction of slippage of bras, following experiments were performed. The subjects consisted of two female groups: a young group of 9 females (19-22 years old) and a middle-aged group of 6 females (40-62 years old). To clarify the body features of the breast, 3D shape of body using 3D image analysis, the breast compression deformation and fat thickness using ultrasonic diagnostic imaging were measured. 3D motion analysis using high-speed cameras was performed to measure breast vibration and a slippage of bras. The wear condition of the bras were following 4 types, a shape revised bra with and without wire, a sports bra and braless. The movement was forward flexion (180). Following results were obtained. By 3D motion analysis using high-speed cameras, control breast vibration effect of a sports bra is higher than other types of bras and braless. Breast vibration of middle-aged group is bigger than that of a young group and the difference according to the bra became small. For middle-aged group, the thicker the subject's breast fat thickness was and the bigger the subject's breast cup size was, the larger the breast vibration and the bra slippage were. For young group, the smaller the breast compressive deformation was, the smaller the breast vibration was. A clothing pressure of sports bra was smaller than that of the shape revised bra significantly both at the top of breast and at the side panel, it was opposite at the under-breast position. There was a correlation, in slippage feeling, between vibration feeling and comfort feeling by the sensory evaluation test after the movement. The bra with moderate compression will make woman comfortable because it suppresses the breast vibration and the bra slippage.

To improve the measurement reliability of the evaporative heat resistance of clothes using a sweating thermal manikin, the discrepancy between the Heat Loss (HL) method and the Mass Loss (ML) method was experimentally investigated. A cotton knit suit (C suit) and a waterproof / moisture permeable GORE-TEX® suit worn over the C suit (G suit) were used as imitation skin. The clothing examined consisted of three different ensembles. The analysis of variance, taking into account the above experimental conditions, showed significant differences among the three ensembles for each imitation skin condition. On the other hand, the discrepancy between the HL and the ML methods appeared to be less in the G suit condition than in the C suit condition. The variation of the measured regional evaporative heat resistance in the different imitation skin conditions also substantiates the notion that the discrepancy between the HL and the ML methods can be attributed to the water-absorbing and diffusion characteristics from the skin surface to the clothing. Thus, it may be said that the G suit is an adequate imitation skin for measuring evaporative heat resistance.

As the dogs cannot express their feelings with words, instead of using objective evaluation methods for human beings, the authors evaluated objective preference of dogs in bed selection with behavior analysis by tracking a marker attached to dog's back of the neck. In this study, the staying time in lying position was used as the degree of preference of dog. As a result, staying time in lying position on usual bed tended to be longer than prepared bed. In another test, 7 dogs out of 10 stayed longer on random coil structure cushion rather than on polyurethane cushion. The dog preference was seemingly affected by the property of random coil structure cushion having lower body pressure and lower temperature and humidity between the dog and bed, compared to polyurethane cushion. Therefore, the authors found the dogs choose bed for some reason, and staying time in lying position can be considered useful for evaluation of the preference of dogs in bed.

In the present study, a series of experiments have been performed to discuss changes in temperature evaluation-ability and cutaneous warm and cold sensation thresholds with healthy young, middle-aged, and elderly Japanese males. Fifteen locations in the body have been selected as target locations in the study in order to examine regional difference as well. Local difference was not found to be significant through the ability temperature evaluation test, because the obtained evaluated temperature was almost equal to the given temperature stimulus on the skin surface in each location. In addition, aging effect was not significantly seen in the temperature evaluation test. On the other hand, the results of thermal sensitivity test showed a significant aging effect on both the warm and cold thermal thresholds on the skin surface in each location. The sensitivity to detect warmth or coldness was remarkably greater in the young males than in the middle-aged and elderly males.