The purpose of this study was to determine the morphologic effect of immobilization on rat soleus muscles in shortened and lengthened positions. Sixteen male Wister rat were divided into two groups, an immobilization (n=8) and a control (n=8) groups. In an immobilization group, both ankles were immobilized with a cast for four weeks, so that the right ankle was in a full plantar-flexion, and the left in a full dorsiflexion. Thus, soleus muscles were immobilized in shortened and lengthened positions. After experiments, the soleus muscle was then extracted and morphological study was conducted using a light and scanning electron microscope. The soleus muscle in the shortened position became more atropied compared to lengthened position. Amount of connective tissue increased, sarcomere lengths decreased, and the transverse component of collagen fibrilles increased in the shortened position. But sarcomere lengths in the lengthened position did not significantly differ from that for the control, and the longitudinal component of collagen fibrilles increased in the lengthened position. The results suggest that muscle stretch may play a preventive role in disuse atrophy, shortening of muscle fibers and endomysium, and the decrease in muscle extensibility.

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The main purpose of this study was to investigate the cardiovascular responses during exercise in patients with non-insulin-dependent diabetes mellitus (NIDDM)-complicated myocardial infarction (MI). There were 120 MI subjects. Sixty of them who had NIDDM (DM group) were matched with 60 non-NIDDM patients (non-DM group) for peak oxygen uptake (VO₂), age, weight, height, body mass index (BMI), creatine kinase-MB (CK-MB), and ejection fraction (EF). These patients performed cardiopulmonary exercise testing using a ramp treadmill protocol; exercise was performed 1 month after the onset of MI. VO₂, and oxygen (O₂) pulse at the anaerobic threshold (AT) were investigated to measure temporal changes in exercise tolerance. At the respiratory compensation point (RCP), tidal volume (TV) was measured as an index for pulmonary capillary wedge pressure (PCWP), end tidal CO₂ (ETCO₂) was measured as an index of reserved cardiac output, and the ventilatory equivalent for CO₂ (VE/VCO₂) was measured as an index of ventilation efficiency. There were no significant differences between the two groups with respect to EF, O₂pulse, and HR at rest. However, HR increased with regard to exercise time (defined as and HR slope). TV, and ETCO₂ at the RCP were significantly lower, and VE/VCO₂ at the RCP was significantly higher, for the DM group than for the non-DM group. No significant correlation was found between hemoglobin A1c (HbA1c) and, AT or peak VO₂. Patients with NIDDM-complicated MI had impaired submaximal cardiopulmonary responses to exercise, even while their cardiac function at rest and peak VO₂ were similar to those of the non-DM group. These findings suggest that ventilation-perfusion mismatch decreased cardiac output reserve, and increased PCWP during exercise. In addition, the non-DM group has an impaired exercise performance not associated with the degree of glycemic control provided that it is not an extremely serious case.

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This study examined the activity of muscles in the hip joint during step-up exercises. Of 13 healthy males, rectified filtered electromyography of the gluteus maximus, gluteus medius, adductor magnus, tensor facia latae, and rectus femoris were recorded in nine step-up patterns that differed in step direction and step height. Two-factor factorial ANOVA was used as the statistical analysis with a significant level of 0.05.
The result showed that step direction significantly affected muscle activity in the gluteus medius, and tensor facia latae. Muscle activity in the gluteus maximums, gluteus medius and tensor facia latae were significantly increased by higher step height. Interaction effects between step direction and step height were detected in the muscle activity of the adductor magnus and rectus femoris.
Step direction and step height would differently affect the activity of muscles in the hip joint during step-up exercise.

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This study elucidates factors and weights (odds ratio) related to the awareness of bullying at geriatric hospitals and special senior-citizen care homes. It also obtains data of a high reliability in order to devise simpler forecasting factors for preventing bullying of senior citizens in so-called long-term care facilities.
The results show that the experienced awareness of bullying in geriatric hospitals was 3.0% and of being bullied was 19.0%. In special senior-citizen care homes, awareness of bullying was 15.3% and awareness of being bullied was 29.4%. In response to the question, “Who were you bullied by?”, the percentage of those who said they were bullied by patients was 53.3% at geriatric hospitals and 56.5% at special senior-citizen care homes. Those who said that the bullying was done by a care giver were 26.7% in the geriatric hospitals and 17.3% in the special senior-citizen care homes. In awareness other than that of bullying, the same trend was generally observed.
The analysis using a logistic regression model showed that the factors (odds ratio) having a meaningful effect on the awareness of being bullied in the geriatric hospitals were unyielding character (16.7) and a high value (3.9) on Zung's self-rating depression scale. In the special senior-citizen care homes, a high value (2.5) only in Zung's self-rating depression scale was observed. Consequently, depression is a related factor in the awareness of being bullied that is common to both the geriatric hospitals and the special senior-citizen care homes.
These results suggest a probability of predicting those who will be aware of being bullied, and a need for proper response to the problem of bullying in senior-citizens in long-term care facilities.

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