An experiment was conducted with ten elderly people, their average age 70.2 ± 5.8, to study the changes in the autonomic nervous system before and after a five-minute exercise using an ergometer. The intensity of the exercise was 30% and 50% load, the target heart rate figures were calculated based on Karvonen's formula. The RR interval was measured by converting the results of an electrocardiogram into a digital recording at 1 msec resolving power. Along with this RR interval, the heart rate variability was used to analyze the autonomic nervous system function. The result showed that the function of the sympathetic nervous system was increased by exercise and continued to increase for a while after the exercise had been stopped. Although the increase in the function of the sympathetic nervous system was prolonged in the case of the exercise conducted at the 50% intensity-level, there was no significant difference in the increase between this and at 30%. The function of parasympathetic nervous system was decreased by exercise and recovered soon after the exercise stopped. There was no significant difference between the two types of exercise. The result of the experiment suggests that the difference in the intensity of exercise, 30% and 50%, does not create any significant difference in the change of the function of autonomic nervous system.

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The effect of body-weight-support treadmill training (BWSTT) on walking ability of patients with nontraumatic incomplete spinal cord injury was examined. Study subjects were comprised of three patients who had underwent surgical operations, one of whom had incomplete tetraplegia and the others who had incomplete paraplegia. All subjects initially received conventional physical therapy beginning 7 days after operation, followed by BWSTT intervention. To examine the changes in lower limb muscle strength and walking ability, the American Spinal Injury Association Impairment Scale (ASIA) and Lower Limb Motor Score (LLMS), Functional Independence Measure for locomotion (FIM), walking speed, average step length, and cadence were evaluated. Little changes in ASIA and LLMS were observed after BWSTT, but FIM improved from 1 (complete dependence) to 5 (supervision) or 6 (modified independence). Walking speed, step length and cadence were also enhanced. Although BWSTT had only a little effect on improving paralysis or lower limb muscle strength of patients with incomplete spinal cord injury, it appeared to enhance walking ability, suggesting its effectiveness as a task-oriented training method.

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Patients with osteoarthritis of the hip (hip OA) often present an abnormal gait. To assess an abnormal gait objectively in patients with hip OA, gait parameters were developed by means of power-spectrum (PS), root mean square (RMS), auto-correlation (AC), and cross-correlation (CC) of trunk acceleration measured using a tri-axial accelerometer during free walking. The validity of parameters was examined by comparing those of 55 patients with unilateral hip OA and 31 normal control subjects and by analyzing correlations between parameters and clinical scores (Harris hip score, radiographic stage, walking score, and 10m maximum walking speed) in the OA group. There were significant differences in all parameters of three axes (p < 0.05) between patients and control subjects. PS and AC correlated significantly with all clinical scores (0.36 < r < 0.76 and 0.30 < r < 0.74, respectively). RMS and CC of anterior-posterior and vertical axes correlated with the majority of clinical scores (0.32 < r < 0.62 and 0.31 < r < 0.51, respectively). Among clinical scores, gait parameters had relatively strong correlations with walking-related indices (walking score and speed). These results suggest that trunk acceleration is useful to develop gait parameters for the objective assessment of an abnormal gait in patients with hip OA.

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The purpose of this study was to investigate changes after denervation in rats diaphragm. Old (2-year, n = 16) and young (10-week, n = 16) male Wistar rats were used. The unilateral diaphragms of eight rats in each age group was denervated by cutting the phrenic nerve at the cervical level, and sham operation was performed on the other eight in each. The undenervated side diaphragms of old and young sham rats were studied to investigate the age-related changes. Four weeks after the denervation, isometric contraction properties, fiber type composition, and expression of myosin heavy chain (MHC) isoforms in all groups were observed. The changes caused by denervation were observed in each age group. The difference of the changes was compared between old and young groups. After the denervation, in the young rats, the area of slow oxidative (SO) fibers were not significantly different from those of the same age sham group. Further fast-twitch oxidative glycolytic (FOG) fibers were significantly larger than those of the same age sham group. On the contrary, in the old rats, the area of SO fibers and FOG fibers were significantly smaller than those of the sham group. The changes caused by denervation were different depending upon the case of the young rats and that of the old rats. The characteristics of slower muscles in the diaphragm of young rats after the denervation were considered to be due to the effect of the stretch stimuli caused by the respiratory contraction of the contralateral diaphragm.

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Problems of “floating toest”, toes do not contact with the ground, have recently been marked. In the present study, plantar contact with the ground was surveyed in 155 healthy adults, for the purpose of clarifying the actual state of toe contact.
In the natural closed foot position with the eyes open, insufficient toe contact in either foot was seen in 66.0% for males and in 76.2% for females, showing that females tend to have problems on contact toe more frequently than males. It was confirmed that, on the fifth toe in particular, floating toe accounted for 46.0% in right foot and 30.0% in left foot in males, and it accounted for 38.7% in right foot and 35.8% in left foot in females. In addition, the incidence of floating toe greatly decreased in the forced closed foot position with the eyes open, compared with the natural closed foot position with the eyes open. Incomplete contact with the ground was proved to account for 22.0% in males and 35.2% in females, confirming that many healthy adults whose toes could not contact with the ground completely in a static standing position were present.

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[in Japanese]

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