• Journal of Oral Medicine and Pain
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• v.15 no.1
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• pp.27-35
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• 1991

In order to evaluate muscular activity patterns of masticatory muscles and asymmetry patterns of muscular activity according to the levels of occlusal force, twenty-one individuals of age ranged from 23 to 27 years were examined. They were selected according to the following criteria : 1) no symptoms of temporomandibular disorder, 2) complete dentition except third molars, 3) normal or Angle's class I molar relationship and 4) no experience of dental treatment. The electromyographic amplitudes was measured for evaluation of muscular activity and asymmetric patterns of masseter and anterior temporal muscle during unilateral clenching at the levels of 10%, 20%, 40% and 50% of the maximum occlusal force by use of electromyogram and bite force meter. The obtained results were as follows : 1. The muscle activity indices of masticatory muscles of clenching side at the clenching levels of 10%, 20% and 30% of the maximum occlusal force were -19.12, -9.87, -0.49%, so that activity of anterior temporal muscle was dominant than that of masseter muscle. At the levels of 40%, 50% of the maximum occlusal force, muscle activity indices were 4.68%, 6.70%, so that activity of masseter was dominant at all level and as the levels of occlusal force was increased, muscular activity index was tend to decrease. 2. In masseter, asymmetry indices of muscular activity at the levels of 10%, 20% of maximum occlusal force were -10.34 and -1.24%, so that muscular activity of non-clenching side were dominant and at the levels of 30%, 40% and 50% each of maximum occlusal force, muscular activity was dominant on clenching side as 4.68, 7.18 and 10.9%. In anterior temporal muscle, asymmetry indices were 33.38%, 25.46, 2095, 10.23 and 15.45% at the levels of 10%, 20%, 30%, 40% and 50% each of maximum occlusal force, so that activity of clenching 15.45% at the levels of 10%, 20%, 30%, 40% and 50% each of maximum occlusal force, so that activity of clenching side was dominant than that of non-clenching side at all levels, but as the levels of occlusal force was increased, asymmetry indices of muscular activity was tend to decrease. 3. Between both sides, average electromyographic amplitudes of masseter and anterior temporal muscle were correlated, so that as the levels of occlusal force was increased, average electromyographic amplitudes of both side in same muscle were increased proportionally. But asymmetry indices between muscular activities of masseter and anterior temporal muscle were not correlated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.893-894
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• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.903-906
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• 2005

The purpose of this study was to analyze the muscular force of swing using the soft golf club in comparison with the muscular force of swing using normal golf club. The subject was normal adult (twenties) and performed swing motion using normal and soft golf club. And then we compared muscular power soft golf club with normal golf club of the subject. The muscular power of the subject was measured by MP 100(BIOPAC Systems, Inc.). For the analysis of muscular power of swing using soft golf club, we measured EMG(Electromyography) of the subject. The position of muscle was deltoid, latissimus dorsi, external oblique and rectus abdominis of the upper limbs and rectus femoris, biceps femoris, gastrocnemius and soleus of the lower limbs. The result of experiment, muscle pattern of swing using soft golf club was similar to pattern of swing using normal golf club and muscular power of subjects using the soft golf was smaller than normal golf.

• Journal of Biomedical Engineering Research
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• v.31 no.3
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• pp.217-226
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• 2010

The lower limb orthosis with a pneumatic rubber actuator, which is intended for the assistance and the enhancement of muscular activities of lower limbs was developed in this study. Compared to other knee extension assistive devices being developed by other researchers, our device is designed especially for the elderly people and intended only for slight assistance so that the subjects can keep their muscular strength. For the effectiveness of system, muscular activities of major muscles in lower limbs during sit-to-stand (STS) and squat motion were measured and analyzed. Subjects were performed the STS and squat motion with and without lower limb orthosis. We made comparison muscular activities between with and without lower limb orthosis. Lower limb orthosis was controlled using muscular stiffness force feedback that is controlled by muscular activities of the measured muscle from force sensor. For analysis of muscular activities, electromyography of the subjects was measured during STS and squat motion, and these were measured using MP 150(BIOPAC Systems, Inc.). Muscles of interest were rectus femoris(RF), vastus lateralis(VL), vastus medialis(VM) and vastus intermedius(VI) muscles in lower limbs of the right side. A biodex dynamometer was used to measure the maximal concentric isokinetic strength of the knee extensors of wearing and not wearing orthosis on right side. The test were performed using the concentric isokinetic mode of test with the velocity set at 60°/s for muscles around the knee joints. The experimental result showed that muscular activities in lower limbs wearing orthosis using muscular stiffness force of a vastus medialis muscle was reduced and knee extension torque of an knee joint wearing lower limb orthosis was increased. With this, we confirmed the effectiveness of the developed lower limb orthosis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.944-947
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• 2004

The purpose of this study was to identify the characteristics of muscular power by COP(center of pressure) training according to the angle variation of tilting bed. We changed the angles of tilting bed(up-down direction 0$^{\circ}$, 15$^{\circ}$, 30$^{\circ}$, 45$^{\circ}$ and right-left direction -15$^{\circ}$, 0$^{\circ}$, +15$^{\circ}$) for the correlation between angles and muscular power. And we measured EMG(electormyography) of lower limbs muscle(rectus femoris, biceps femoris, and gastrocnemius, tibialisa anterior) during COP training. COP training was divided by the COP trace training(in all direction) and sine wave trace training(vertical and horizontal direction). As the result, we obtained the improvement effect of COP training and we showed that electromyography(EMG) variations of lower limbs muscle on the angle variations of tilting bed were investigated.

• The Journal of Korea Robotics Society
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• v.5 no.1
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• pp.48-54
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• 2010

Ankle-foot orthosis with a pneumatic rubber actuator, which is intended for the assistance and the enhancement of ankle muscular activities was developed. In this study, the effectiveness of the system was investigated during plantarflexion motion of ankle joint. To find a effectiveness of the system, the subjects performed maximal voluntary isokinetic plantarflexion contraction on a Biodex-dynamometer. Plantarfexion torque of the ankle joint is assisted by subject's soleus muscle that is generated when ankle joint do plantarflexion motion. We used the muscular stiffness signal of a soleus muscle for feedback control of ankle-foot orthosis as physiological signal. For measurement of this signal, we made the muscular stiffness force sensor. We compared a muscular stiffness force of a soleus muscle between with feedback control and without it and a maximal plantarflexion torque between not wearing a ankle-foot orthosis, without feedback control wearing it and with feedback control wearing it in each ten elderly adults. The experimental result showed that a muscular stiffness force of a soleus muscle with feedback control was reduced and plantarflexion torque of an ankle joint only wearing ankle-foot orthosis was reduced but a plantarflexion torque with feedback control was increased. The amount of a increasing with feedback control is more higher than the amount of a decreasing only wearing it. Therefore, we confirmed the effectiveness of the developed ankle-foot orthosis with feedback control.

• PNF and Movement
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• v.8 no.3
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• pp.9-16
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• 2010

Purpose : The purpose of this study was to investigate effects of kinesio taping of thigh muscle on isokinetic muscular function during closed kinetic chain exercise of lower extremity. Methods : Twenty healthy males were participated in this study. The isokinetic muscular function of closed kinetic chain were measured for peak torque, peak torque % body weight, average power, max rep tot work before and after application of kinesio taping on thigh muscles. Results : At $60^{\circ}/s$ peak force and peak force % body weight were significant increased in both extension(p<0.01) and flexion(p<0.001) after applying kinesio taping. At $180^{\circ}/s$ average power was significant increased in both extension and flexion after applying taping(p<0.001). At $240^{\circ}/s$ max rep tot work was significant increased in both extension(p<0.001) and flexion(p<0.05). Conclusion : This study suggests that application of kinesio taping on thigh muscle was more effective to improve isokinetic muscular function in closed kinetic chain exercise of lower extremity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.4
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• pp.725-728
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• 2008

An elbow orthosis with a pneumatic rubber actuator has been developed to assist and enhance upper limbs movements and has been examined for the effectiveness. The effectiveness of the elbow orthosis was examined by comparing muscular activities during alternate dumbbell curl motion wearing and not wearing the orthosis. The subjects participated in the experiment were younger adults in their twenties. The subjects were instructed to perform dumbbell curl motion in a sitting position wearing and not wearing orthosis in turn and a dynamometer was used to measure elbow joint torque outputs in an isokinetic mode. Orthosis was controlled using contractile muscle force that is measured from force sensor through cDAQ-9172 board. The air pressure of the pneumatic actuator was 0.3MPa the most suitable air pressure. For the analysis of muscular activities, Electromyography of the subjects was measured during alternate dumbbell curl motion. The experiment results showed that the muscular activities wearing the elbow orthosis were reduced. With this, we confirmed the effectiveness of the developed elbow orthosis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.415-422
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• 2020

This study investigates the relationship between muscular strengths and gait characteristics of the elderly. Totally, 107 subjects, aged 65 to 85 years, participated in this study. Researchers measured muscle strengths (grip force, toe grip force, gluteus medius, and gluteus maximus forces) and walking characteristics (walking speed, cadence, step length, single leg support, and double legs support). Dynamometers and inertial measurement unit-based shoe systems were used for measuring muscular strength and gait characteristics, respectively. No significant difference was observed in strengths and walking characteristics between the young elders (YE, 65-74 years) and the old elders (OE, 75-85 years). For each age, muscular strength significantly correlated with some gait parameters. Forces of gluteus medius and gluteus maximus muscles showed better significant correlations between some gait parameters for all age groups, as compared to grip force and toe grip force. Regression coefficients between walking speed and grip force did not vary with age. We conclude that muscular strengths in OE better explained the gait characteristics than in YE subjects. Even though grip strength is an easily measured variable for senior fitness test, forces of gluteus medius and gluteus maximus muscles are more meaningful for understanding the walking characteristics of elderly people.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.2
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• pp.101-110
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• 2007

This study was performed to find out hazardous factors in the loaded works of muscular skeletal disorders(MSDs) for four company attached to dining workers from October 2005 to June 2006. The results are summarized as follows. 1. 42.5% of workers in study group were 40-50 years old, and females were higher than males, and the average of body weight was 70kg, 57kg in males and females, respectively. Working time per day was mostly 7-9hours, and the rate of worker who had never education and training was 46%. 2. The upper part and right part of body were higher than lower part and left part in symptoms of muscular skeletal disorders. Body parts which complained of symptoms were the order of right shoulder(55%), right arm(54%), right hand,(40%) waist(35%), leg(25%), and neck(24%). 3. The results of evaluation in the loaded works of muscular skeletal disorders to cooking, dish supply, preparing side dish, and washing the dishes and cleaning the floor of cooking room using RULA and OWAS checklists was action level 4(potential hazards, needs of change workplace), and the result of evaluation using back compressive force needed control measures as 779.27 lbs~1,274.04 lbs. In a view point of the result of this study, large dining rooms should be designed by ergonomic technology for the work surface height, width, and depth. The height of carrying car should be lower to 70cm, and repetitiveness and handling weight should be reduced by mechanical means, and education and training also should be performed for all of workers positively.