The aim of this investigation was to clarify the effect of change in posture and motor coordination by repetition of the same task. Eleven healthy subjects with a mean age of 23.6 ± 2.6 years participated in this study. They were ordered to reach forward as a motor task. The sway area of the center of pressure (COP) and electromyography (EMG) of the lower extremity muscles were measured in the reaching position and the displacements of COP and body segment positions were measured. EMG was measured at M. Gluteus Maximus (GM). M. Semimembranosus (SM), M. Tibialis Anterior (TA) and M. Gastrocnemius (GC). The displacement of body segments was measured at position of the wrist, shoulder, hip and knee joint. The task was repeated 10 times, and results of the first and final trials were compared. In the reaching position in the first trial, the sway area of the COP increased. All muscles measured showed higher activity than at the starting position. The COP moved forward, but the position of the hip joint moved backward while reaching. In the final trial, the sway area of the COP decreased compared with the first trial. The only muscles that increased significantly at reaching position were SM and GC in the final trial. The distance that the COP moved increased, while the backward movement of hip positions became shorter than in the first trial. These results suggest that repetition of a reaching task may improve the stability of the posture by changing postural control strategy.

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The purpose of this study was to determine the influence of changes in the sagittal plane center of foot pressure (CFP) during squatting on the muscle activity of the lower extremities. Twelve healthy subjects with a mean age of 25.9 years, participated in this study. Electromyographic muscle activity during squatting was measured in the rectus femoris, vastus medialis, vastus lateralis, biceps femoris, semimembranosus, gastrocnemius and tibialis anterior. Squatting was performed at three knee joint flexion angles (30°, 60°and 90°), and three CFP positions (neutral, forward, backward). There were significant differences with changes in CFP in muscle activity of the rectus femoris, vastus medialis, vastus lateralis and tibialis anterior at all knee flexion angles. The highest muscle activity of these muscles was shown during squatting in backward CFP at the deep knee flexion angles. Muscle activity of the biceps femoris, semimembranosus and gastrocnemius tended to be higher in forward CFP, but was still low at less than 20 percent. These results suggest that squatting in backward CFP at deep knee flexion angles is most effective as muscle strengthening exercise for the quadriceps femoris and tibialis anterior.

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Separately evaluating movement of the scapulohumeral joint and scapulothoracic joint is important as part of conducting a physical therapy program for shoulder joint injuries. Our measurement method ensures an easy and convenient way of evaluating shoulder joint movement in daily medical treatment, but it is thought that standard values are necessary when evaluating individual cases. In order to define a standard value numerically as an indicator of the movement of the scapulohumeral joint and scapulothoracic joint for our measurement method, the trunk-to-spine scapula angle was measured in healthy individuals as subjects (24 cases, 48 shoulders) without shoulder joint injuries, while having them raise the upper limb in the scapular plane at 0-, 90-, and 150-degree angles between the trunk and upper arm. The results were that scapulothoracic joint movement in trunk-to-upper arm angle was 12.7 ± 5.8 degrees in the 0-90 degree interval, and 33.7 ± 6.3 degrees in the 90-150 degree interval. These results differ from those of other researchers, and could become basic data for this diagnostic method.

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The purpose of this study was to investigate the relationship between lip closing functions and the coughing and choking of children and adults with severe motor and intellectual disabilities (SMID).
The subjects were 92 persons with SMID, who suffered from dysphagia. Their age range was from 3 to 55 years (mean: 28.1 years). The relationship between lip closing functions (in taking of food, drinking, mastication, and swallowing) and the general symptoms of aspiration (coughing and choking) were evaluated.
The results were as follows: (1) the subjects who were able to close their lips when taking in food and liquids were half of those who were able to close their lips during mastication and swallowing: (2) for the subjects who were able to close their lips when taking in food and liquids, the ratio of those who were able to close their lips during mastication and swallowing was significantly higher than that of those who were not able to close their lips: (3) the ratio of coughing or choking of those who were able to close their lips when taking in food and liquids was significantly lower than that of those who were not able to close their lips when taking in food and liquids.
That is to say, for the subjects who are able to close their lips when taking in food and liquids, there is a high possibility of their lips closing during mastication and swallowing and the ratio of coughing or choking is low.
These results suggest that lip closing functions in taking of food and liquids are closely related to mastication and swallowing and have a great influence on the coughing and choking.

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