This study aimed to investigate the relationship between the muscular strength of the lower extremity in a load side and the characteristics of center of foot pressure (COP) during landing after crossover stepping in the elderly. The study population comprised 8 elderly subjects (average age, 75.8±8.0 years) and 9 young individuals (average age, 21.6±2.5 years). Using a separation-type force plate, we measured the deflection characteristics of the COP; these were defined by the root mean square of positional change (COP-RMS) and the deflection velocity of the COP (COP-Vel) during landing after crossover stepping. Furthermore, we measured the muscular strength of the lower extremity by using a hand-held dynamometer. By using multiple regression analysis, we detected the calculated muscular strength as the independent variable of the deflection characteristics of the COP. Compared to the young group the elderly group showed significantly higher anterior-posterior COP-RMS values (p<0.05) and lower lateral COP-Vel values (p<0.001). In the elderly, the muscular strengths of the tibialis anterior and adductor magnus were detected as a significant independent variable of the anterior-posterior COP-RMS (R²=0.85, Rˆ²=0.76, p<0.01) and lateral COP-Vel (R²=0.75, Rˆ²=0.65, p<0.05), respectively. With regard to the COP deflection characteristics during landing after crossover stepping in the elderly, we recognized the diagnostic character of the anterior-posterior COP-RMS and lateral COP-Vel. Furthermore, it was suggested that the muscular strengths of the tibialis anterior and adductor magnus played a role in regulating the COP deflection characteristics.

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The purpose of this study is to evaluate the association of abdominal fat thickness with obesity-associated metabolic risk factors. A total of 186 men and 350 women aged 30–78, who were voluntary participants in a community-based health screening program, were examined for body mass index (BMI), waist circumference (WC), and WC-stature ratio (WCSR). Using the ultrasonographic method, the maximum thickness of the preperitoneal fat layer (Pmax) and the minimum and maximum thicknesses of the subcutaneous fat layer (Smin and Smax) in the abdominal region were measured and the abdominal wall fat index (AFI=Pmax/Smin) was calculated. Each measurement was used as a main predictor in the logistic model where the presence of a metabolic risk factor (high blood pressure, high triglyceride, low high-density lipoprotein cholesterol, high glucose, and high uric acid) was predicted. Common covariates in the models were age, smoking status, drinking habit, and overall physical activity. Both WC and WCSR, which behaved in the same manner as BMI, showed a significant association with the majority of metabolic risk factors, but these anthropometric indices were not independent of the confounding effect of BMI. In relationship with atherogenic dyslipidemia, Smax in women and Pmax in both men and women were significant predictors independent of BMI. AFI was also found to be a BMI-independent predictor of atherogenic dyslipidemia in both genders. In men, AFI and high glucose were not significantly associated; in women, they were inversely associated. No measurement showed a significant association with high uric acid. Results suggest that ultrasonographic evaluation of abdominal fat is useful for identifying those at atherogenic risk. A larger sample of subjects in terms of body composition may be required to confirm the usefulness of ultrasonographic evaluation of high glucose.

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This study focused on whether wheelchair users showed enhanced ability to estimate the space required for locomotion with familiar and unfamiliar wheelchairs. Tetraplegic participants, who lacked somatosensory input from the upper limbs and were unable to obtain information about the dimensions of a wheelchair from their hands, and able-bodied control participants made judgments of whether a doorway was passable with their usual form of locomotion (use of a familiar wheelchair or walking) or a new form of locomotion (use of an unfamiliar wheelchair for both groups). The relative perceptual boundary was determined, which was the ratio of the perceptual boundary between passable and impassable widths to the minimum passable widths. Tetraplegic participants accurately determined passable doorways in both familiar and unfamiliar wheelchairs. The control participants showed less accuracy for the wheelchair condition than for the walking condition. The findings obtained from the tetraplegic participants suggest that adaptation to altered body dimensions occurs in a short time only under a well-learned, familiar form of locomotion. The findings also suggest that individuals are likely to rely more on visual memory of a passable space than somatosensory information about the dimensions of the wheelchair when determining passable doorways during locomotion.

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The objective of this study is to measure muscle activity during walking in order to estimate the distance that must be traveled for safe evacuation when the effect of the flow velocity changes. In the present study, electromyogram data were measured for six muscles on the right lower extremity, namely, the rectus femoris, vastus lateralis, long head of the biceps femoris, medial gastrocnemius, tibialis anterior, and gluteus medius. The experimental conditions included walking through a flooded hallway with 0.5-m-high water flowing at four different flow velocities (0, 0.47, 0.76, and 1.12 m/s in the direction opposite to the walking direction) and walking on dry ground. From the results, the tibialis anterior exhibited the highest muscle activity of up to 85% MVC with the toe off the ground when the flow velocity was the highest, suggesting that the subject tended to avoid stumbling against water flow during ankle dorsiflexion. The activity of the gluteus medius increased with the flow velocity, suggesting that the subject tried to stabilize the pelvic area to avoid falling. Empirical data for muscle activity during walking under flooded conditions in association with water height and flow velocity will contribute to better understanding safe evacuation from flooded urban underground areas.

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The effects of communicating during and after expressing emotions and receiving empathy after exposure to stress were investigated for 18 female students (9 pairs). After mental and physical tasks, a subject spoke to a listener about the stress task. In Experiment 1, responses to speaking about negative emotions aroused by the task (the “with emotion” condition) were compared to speaking about only objective facts about the task (the control). In Experiment 2, responses to empathetic reactions from the listener (the “with empathy” condition) were compared to no reaction (the control). Electroencephalograms were recorded, and heart rate variability (HRV) was calculated from electrocardiogram data. Subjective stress was estimated by a visual analog scale. Experiment 1 demonstrated that expressing emotions activated the left temporal region (T3) in the “with emotion” condition. In Experiment 2, physiological responses depended on cognition of different elements of empathy. During communication, feeling that the listener had the same emotion decreased the subject's T3 activity and sympathetic activity balance indicated by HRV. After communication, feeling that the listener understood her emotions decreased bilateral frontal and temporal activity. On the other hand, subjective stress did not differ between conditions in both experiments. These findings indicate that the comfort of having shared a message reduced physiological activity, especially in the “with empathy” condition. Conversely, even in the “with empathy” condition, not sharing a message can result in more discomfort or stress than the control. Sharing might be associated with cognition of the degree of success of communication, which reflected in the physiological responses. In communication, therefore, expressing emotions and receiving empathy did not in themselves reduce stress, and the level of cognition of having shared a message is a key factor in reducing stress.

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This communication discussed the linguistic usages of terms expressing perceived thermal sensation in English, Japanese, and Korean. In particular, ttatthada (warm) in Korean and atatakai (warm) in Japanese represents a thermally positive feeling. For Koreans and Japanese, to explicitly express thermal sensation as warm is to implicitly connote a thermally comfortable or satisfied state. When ‘comfortably warm’ and ‘uncomfortably warm’ are translated into Korean or Japanese they sound like a redundant expression and possibly an oxymoron, respectively. Subjective thermal perception has been measured using particular languages and then translated into English for international communication. International Standards (ISO) in environmental physiology or ergonomics have played an important role in setting criteria, unifying international research, and suggesting the direction of further research. However, the differences in linguistic dimensions across cultures may cause confusion when interpreting thermal perceptions measured by different languages. It is conceivable that similar difficulties exemplified in Korean and Japanese may exist in other languages. Therefore, international standards for the measurement of subjective thermal perceptions need to take into account the variations of interpretation given to these descriptors across cultures. For international standards to be internationally valid, systematic research on linguistic differences in thermal perceptive words is required.

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