The purpose of this study was to investigate the effect of ageing on body sway during sit-tostand movement from a chair and on quadriceps muscle strength in the elderly population. A total of 275 community dwellers volunteered to participate in this study. All subjects signed an informed consent statement prior to participating in this study. They were required to be able to perform a sit-to-stand movement from a chair independently. The postural sway for the subjects during the sit-to-stand movement from the chair was measured using a stabilometer. The analog signals of the subjects' center of pressure in the anterior-posterior direction (%Y-axis) derived from the stabilometer were recorded. The maximum isometric muscle strength of knee extension was measured using an isometric dynamometer at 90 degrees flexion of the knee joint. Our results demonstrate that as age increased, lower extremity muscle strength decreased, and forward shift of the center of pressure also decreased. It is possible that the elderly subjects could not use their propelling power because of decreased lower extremity muscle strength. Therefore, the forward shift of the center of pressure of elderly subjects also decreased causing them difficulty in standing up from a chair. Therefore, we believe that we there is a need to educate elderly people about accurate sitto-stand movement and the importance of lower extremity muscle strength exercise.

The purpose of the present study was to examine the relationship between balance performance during one-leg and two-leg standing and leg muscular strength in junior speed skaters, and to formulate one indicator for on-land training. There were a total of 48 subjects comprising 22 junior elite and 26 junior non-elite speed skaters. The method involved analyzing the unit trajectory length (LNG/TIME), the peak value for center of gravity fluctuations (RMS) and the area where fluctuations in the center of gravity are concentrated (SD-A) in keeping one-leg and two-leg standing; and measuring the maximum isometric muscular strength for knee extension with a leg muscular strength measurement device, and thereby calculating a weight-bearing index (WBI). As far as the characteristics for the center of gravity were concerned, significantly lower values in the elite group compared with the non-elite group were exhibited for the peak center of gravity fluctuations (RMS) and the area in which fluctuations in the center of gravity were concentrated (SD-A). However, no significant differences were observed in the unit trajectory length (LNG/TIME). In addition, no significant differences between the groups were observed when the right leg was kept standing. The elite group exhibited significantly higher values in the weight-bearing index (WBI) compared with the non-elite group for both legs. With regards to the differences between the left and right leg WBI, the elite group exhibited significantly higher values for the left leg than the right leg, but no significant difference was observed between left and right in the non-elite group. Based on this, it is suggested that there is a need to carry out qualitative training for improving the ability to keep the left leg standing in a posture simulating skating, and to carry out quantitative training for increasing the muscle strength of knee extensors, in order to improve the competitiveness of junior speed skaters.

The resected mass consisted of very tiny rods, and x-ray diffraction analysis, as well as the component analysis using energy dispersive x-ray microanalysis, revealed the mass to be most compatible with apatite. The back-scattered electron images suggested that precipitation might be a mechanism for development of the calcified mass.

Abstract. When a muscle is used repeatedly for a long time, it often leads to muscular fatigue and muscle soreness. In middle-aged and elderly populations, muscular fatigue and pain during the performance of activities of daily living is a common problem caused by physiological changes in the musculoskeletal system due to the aging process. Microcurrent therapy has been shown to be effective at reducing pain and muscle soreness. For activities such as standing or walking, specially developed shoes (G-man, Busan, South Korea) which are capable of providing microcurrent therapy during the performance of these activities are an advantage as the treatment becomes integrated with the activity being performed. These therapeutic shoes or microcurrent induction shoes could be potentially useful for providing treatment if they were worn during normal activities. The purpose of this study, therefore, was to investigate the effect of these microcurrent induction shoes on pain and muscle fatigue in middle-aged people with plantar fascitis. Subjects were asked to wear their normal shoes and instructed to walk on a treadmill at 2 and 3 km/hr for 10 minutes each. Subjects were then asked to wear the specially designed microcurrent induction shoes for six weeks for at least 4 hours per day during ADL activities such as standing and walking. During the initial evaluation and at the end of the 6 weeks intervention, the electromyographic (EMG) activity of their right tibialis anterior and soleus muscles were recorded, together with their perceived level of foot pain using a Visual Analogue Scale (VAS). The results showed a significant reduction in their VAS scores (p<0.01), and the change in median power frequency of their tibialis anterior EMG recording (p<0.05). In conclusion, this study demonstrated that microcurrent induction shoes were effective in relieving foot pain and muscle fatigue in subjects with plantar fascitis.

No abstract