To evaluate the sleep-improving effects by the mattress easy to move and comfortable to sleep, we estimated sleep feelings by standardized OSA sleep inventory MA version and measured sleep quality by actigraph. Sixteen healthy subjects (6 males, 10 females), aged 61-66, were recorded, sleeping in their homes for 15 consecutive nights under two crossover designed conditions from Friday. A subject slept for 7 consecutive nights (4 adaptation nights and 3 nights for analysis) on his usual bedding first and then for 8 consecutive nights (4 adaptation nights, 3 nights for analysis and excluded last night) on a mattress easy to move and comfortable to sleep. The results showed the sleep on a mattress easy to move and comfortable to sleep indicated better sleep quality measured by actigraph. The results indicate that people may not sleep suitable bedding and the mattress easy to move and comfortable to sleep provide better sleep.

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The purpose of this study was to compare the health status and physical performance (PP) reported by independent elderly Japanese and Korean individuals. A cross-sectional analysis was performed using non-disabled Japanese (n=101) and Korean (n=109) women aged 65 to 84 years. The self-reported health status was determined using a questionnaire in an interview format and various PP tests. The self-rated health reports, graded as fair or poor, revealed that Koreans had significantly better grades (31.2%) than (P<0.001) the Japanese (17.8%). Further, the SF-36 health survey revealed that physical function was significantly lower in Koreans (67.1) than in Japanese (80.1) individuals. In addition, Japanese individuals scored better on 7 PP tests (P<0.001) than Korean individuals, while the latter scored higher than the former in the functional reach and the 3-m tandem walk. Therefore, we recommend an approach to increase the physical activity for independent elderly Korean individuals to prevent physical frailty. In particular, it is critical to introduce policies for maintaining and promoting PP for such individuals.

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The purpose of this study was to examine the influence of icing on relaxed elbow angle, flexed elbow angle, range of motion (ROM), muscle soreness, upper arm circumference, maximum isometric torque, plasma creatine kinase (CK), myoglobin (Mb), protein carbonyl and thiobarbituric acid-reactive substances (TBARS) after eccentric contractions (ECC). Twelve male subjects (control group n=6, icing group n=6) performed 70 maximal ECC with the elbow flexors of the non-dominant arm. Isometric torque in the icing group significantly decreased 3 days and 7 days after ECC compared to the control group. These results suggest that icing is ineffective to reduce in direct markers associated with ECC-induced delayed-onset muscle soreness (DOMS) and to enhance the recovery of muscle function.

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To design a suitable hand-controlled joystick, it is necessary to study the sensory motor characteristics of the force and torque exerted by the hand. In the last paper, we reported the characteristics of the young male and female subjects. To compare the characteristics between young subjects and elderly subjects, the exerted torque data of elderly subjects were measured on actual operating postures. This paper focuses on the following points. 1) Comparisons of the minimum torque differences exerted by the dominant hand between the subject's groups 2) A verification of Weber's law, namely the ratio of the minimum torque to the prior load torque. To measure the torque exerted by a hand, a joystick capable of sensing six axes of force and torque was prepared, and the experiment was performed with 8 male and 8 female (48-66 years old) subjects. The results showed that, a) there is no significant difference about the minimum torque between the elder male and the elder female subjects. And the minimum torques of the elderly is larger than the young's. b) Weber's ratio close to approximately 0.1-0.2 as the prior load torque increases. These results suggest that the minimum torque differs depending on the age difference, and that Weber's law is applicable.

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Few studies have been made on the positive effects of locomotor respiratory coupling (LRC). In this study the effects of LRC were analyzed using airway occlusion pressure (P_<0.1>) as an indicator of respiratory motor output. Nine healthy subjects were asked to take exercise tests on an ergometer initially under spontaneous breathing, and then under LRC-induced state. Based on the LRC rates obtained, the subjects were divided into high and low LRC groups. In the group with high LRC, the crank rate and heart rate were significantly lower (P<0.01) during LRC-induced period as compared to the rates during the period of spontaneous breathing. ΔVE/ΔP_<0.1>, used as an index of dyspnea was also improved in all subjects of the high LRC group. In the group with low LRC, P_<0.1>, was significantly increased (P<0.01), and breathing frequency was increased, while the tidal volume was decreased and ΔVE/ΔP_<0.1>, was deteriorated in all subjects during LRC-induced period. We concluded that controlling the breathing frequency should be necessary to produce positive effects of LRC in alleviating dyspnea.

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In this study, we transversely and longitudinally analyzed changes in height, body weight, and the body mass index (BMI) in male and female students aged 15 to 20 years over the past 20 years. In both the boys and girls, the body weight, BMI, and standard deviation increased yearly, and this increasing tendency between 5 and 95%ile values was noted in all age groups. Furthermore, the rates of increase in the 95%ile values of the body weight and BMI in the girls were greater than in the boys. Concerning serial changes in the difference between 15 and 19 years of age, the boys' height decreased. In the girls, the 5%ile values of height decreased, and the mean and 95%ile values of body weight increased. Thus, the proportions of obese persons with a BMI of 24 to 28 increased yearly in both the boys and girls, suggesting height prematurity before 15 years of age in boys and a diverse physical status in girls.

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We are contacting a joint examination of a gait evaluation system between Japan and the USA. This evaluation system can be widely used in anthropometry and consists of an EMG amplifier, and an accelerometer. A 3-axis acceleration data and EMG data are transmitted to a PC via Bluetooth communication. This enables an analysis gait pattern, such as walking cycle factors to be calculated from the acceleration wave form and muscle action potential. This research examined the reliability and the reproducibility in the following factors, the acceleration root mean square value, muscle action potential integral value and the gait time parameter. The result showed high reliability (Intra-class correlation coefficient ICC=0.652〜0.846 P<0.01), reproducibility (ICC=0.511〜0.958 P<0.01) validity (Friedman's test P<0.01). This system has a variety of advantages. Such as the wireless nature is low in physical constraints, also it is possible to combine with other measurement sensors. Additionally, a sampling frequency of 1kHz can be recorded in the current wireless communication measurement, which is useful for FFT calculations.

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