• The Korean Journal of Physiology
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• 제18권1호
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• pp.81-96
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• 1984

As the crippled persons work mostly in a sitting position and would be engaged in a foot-pressing job, it is necessary to assess their degree of participation of important muscles in various modes of foot activities. In this regard, it deems to be urgent to establish the reference standards for healthy persons. The present study has been undertaken to determine the degree of participation of the M. tibialis anterior, M. gastrocnemius and M. soleus in heel pressing, foot-flat pressing and forefoot pressing motion under varying forces, and in order to compare the electrical activities of three muscles with each other, and to analyse the time sequence between force and appearance or disappearance of EMG recording. Sixty-three healthy young women ranging from age of 18 to 23 were examined. The results obtained were as follows: 1. Participation of three muscles in foot movement under varying forces: A) Both gastrocnemius muscles or left soleus muscle did not contribute to heel pressing motion. Activity of both tibialis anterior muscles was the greatest among three muscles at heel pressing motion and the degree of their activities was proportional to force. B) Activities of left tibialis anterior muscle and both gastrocnemius muscles were negligible under 3 kg force at foot-flat pressing movement. Left gastrocnemius muscle did not contribute to foot-flat pressing under 6 or 9 kg force. Although activities of both soleus muscles and both tibialis anterior muscles were small, the degree of their activities increased with force at foot-flat pressing movement. C) Activities of both tibialis anterior muscles were negligible under 3 kg force at forefoot pressing motion. Activity of both soleus muscles was the greatest among 3 muscles and the degree of their activities increased with force at forefoot pressing motion. Both tibialis anterior muscles participated in forefoot pressing motion with severe exertion. 2. Electrical activities by foot movement under varying forces : A) Electrical activities were prominent in both tibialis anterior muscles and the level of their activities was linear with force at heel pressing motion. The degree of participation of both soleus muscles was small at heel pressing motion. B) Electrical activity of tibialis anterior muscle was the greatest among 3 muscles at foot-flat pressing movement and was followed by that of soleus muscle. Level of electrical activities increased with force in left soleus muscle and right tibialis anterior muscle at foot-flat pressing movement. C) Electrical activity of both soleua muscles was the greatest among 3 muscles at forefoot pressing movement and that of tibialis anterior muscle was next to soleus muscle. Level of electrical activities was proportional to force in left tibialis anterior muscle, right gastrocnemius muscle and both soleus muscles at forefoot pressing movement. 3. Time between starting signal and initiation of contraction of heel pressing and forefoot pressing motion in 3 muscles was longer than that of foot-flat pressing movement. Time of relaxation in 3 muscles was longer than that of contraction under varying forces. EMG recording appeared before initiation of contraction in both tibialis anterior muscles at heel pressing motion and in both soleus muscles at forefoot pressing movement under varying forces. Time of initiation of contraction was similar in both sides of tibialis anterior muscles under varying forces and time of onset of contraction at foot-flat pressing motion was the shortest. 4. Forefoot pressing movement would be encouraged in paralysis of tibialis anterior muscle, while heel pressing motion would be encouraged in paralysis of triceps surae muscle.

• The Journal of Korean Physical Therapy
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• 제35권3호
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• pp.83-88
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• 2023

Purpose: This study was to investigate the effect of forward head posture (FHP) and round shoulder posture (RSP) on changes in muscle activities according to shoulder flexion and abduction tasks. Methods: Twenty-two male subjects with no history of neurological, musculoskeletal surgery or injuries, or pain in the spine region within the previous 3-month periods were recruited for this study. Craniovertebral angle (CVA) and Scapula Index were measured before performing 90° abduction and flexion tasks holding a 3kg dumbbell. Muscle activities were measured during the tasks. All measurements except height of the acromion were carried out in a sitting position at the height of the subject's knee angle of 90 degrees, and two tasks were randomly performed with the arm that the subject mainly use to throw the ball. The abduction and flexion angles were checked by the examiner using a goniometer beside the subject. Results: Correlation coefficient analysis between Scapular Index and upper trapezius muscle activity during shoulder abduction task showed significant positive correlation. No significant correlation was observed between CVA, Scapular Index, and other muscle activities. Conclusion: FHP showed increased muscle activation, making it difficult to change muscle activity under lower loads, and RSP was correlated with UT activation in shoulder abduction. Therefore, in the RSP, the loaded shoulder abduction is considered a potential risk factor for increasing shoulder muscle tension. This paper proposes an approach to treating RSP before FHP.

• 한국전문물리치료학회지
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• 제26권2호
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• pp.8-15
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• 2019

Background: Improvement of the lumbo-pelvic stability can reduce the compensatory action of the erector spinae (ES) during prone hip extension (PHE). Furthermore, the application of abdominal drawing-in (ADI) maneuver increases the action of gluteus maximus (GM) and decreases the action of ES during PHE by improving the lumbo-pelvic stability. However, the post-ADI exercise effects on PHE, not the real-time application of ADI maneuver, has not been studied. Objects: This study is aimed at investigating the post-ADI exercise effects on the muscle activities of GM and ES during PHE. Methods: A total of 24 female adults participated in the study, and they were divided into two groups: Those with normal abdominal muscles ($n_1=12$) and those with weak abdominal muscles (WA) ($n_2=12$). Before the intervention, the subjects' GM and ES muscle activities during PHE were measured. Subsequently, the two groups were asked to perform the ADI exercise for 10 minutes. After the ADI exercise, the GM and ES activities were equally measured during PHE. Results: The comparison result of the ES muscle activities before intervention shows a significant difference between the two groups (p<.05); the WA group showed higher muscle activities than the normal group. For the within-group comparison, the muscle activities of the ES in the WA group significantly decreased after the ADI exercise (p<.05). For the GM muscle activity, no significant difference was observed in all comparisons (p>.05). For the changes in muscle activities before and after the ADI exercise, a significant difference exists between the two groups only for the changes in ES activities (p<.05); WA group exhibits higher changes than the normal group. By contrast, no significant difference exists between the two groups for the changes in GM activities (p>.05). Conclusion: After the ADI exercise, the compensatory action of ES in the female adults with WC is implied to decrease during PHE.

• The Journal of Korean Physical Therapy
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• 제27권5호
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• pp.315-319
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• 2015

Purpose: The purpose of this study was to investigate the effect of leg-crossing positions on muscle activities of rectus femoris, tensor fascia latae, and hamstring in healthy 20's adults. Methods: Twenty healthy subjects were asked to perform three leg-crossing positions, leg crossing (LC), tailor crossing (TC), and ankle crossing (AC). Surface electromyography (EMG) was used to evaluate the activities of rectus femoris, tensor fascia latae, and hamstring during upright sit posture (UP) and three leg-crossing positions and UP was compared to three leg-crossing positions. Repeated one way ANOVA was used for data analysis. The alpha level was set at 0.05. Results: The results showed significant difference in the muscle activities of rectus femoris, tensor fascia latae, and hamstring among leg-crossing positions. The muscle activity of the rectus femoris was significantly lower in LC and TC positions than UP. The muscle activity of tensor fascia latae was significantly higher in LC position than UP and other leg-crossing positions. The muscle activity of hamstring was significantly higher in LC and TC positions and significantly lower in AC position than in UP. Conclusion: Our study suggests that the activity of hip muscles was affected by pelvic and knee alignment in various leg-crossing positions.

• The Journal of Korean Physical Therapy
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• 제30권1호
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• pp.1-7
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• 2018

Objective: This study aimed to determine the efficacy of flexible pole training combined with lumbar stabilization in improving trunk muscle activities and to investigate the difference according to posture in young adults. Methods: Twenty-five participants were enrolled in this study. The subjects were randomly allocated into either the flexible pole group or the rigid pole group. Participants performed lumbar stabilization exercises on quadruped and curl-up, with the flexible pole or rigid pole. Electromyography was used to assess the percent maximal voluntary isometric contracion (%MVIC) of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spine (ES) muscles. All participants completed one 30-minute session per day, 3 days per week, for 6 weeks. The evaluation was performed before and 6 weeks after the training, and follow-up. The data were analyzed using independent t-test and two-way repeated measure analysis of variance to determine the statistical significance. Results: The flexible pole in curl-up showed significant differences in EO and IO muscle activities compared with the rigid pole. The flexible pole in quadruped showed significant differences in IO and ES muscle activities compared with the rigid pole. The RA, EO, IO, and ES muscle activities of both groups were significantly higher after 6 weeks training. Conclusion: The flexible pole in curl-up and quadruped showed an improvement in trunk muscle activation. The flexible pole combined with lumbar stabilization will be useful as an exercise tool to improve activity of trunk muscles.

• 한국운동역학회지
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• 제25권4호
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• pp.383-391
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• 2015

Objective : The purpose of this study was to investigate the effects of dynamic squats with slope-whole body vibration (WBV) on the trunk and lower limb in muscle activities. Method : 9 healthy women (age: $21.1{\pm}0.6years$, height: $160.5{\pm}1.4cm$, body weight: $50.5{\pm}2.4kg$) were recruited for this study. Muscle activities in the trunk and lower limb muscles, including biceps femoris (BF), rectus femoris (RF), rectus abdominum (RA), gastrocnemius (GCM), iliocostalis lumborum (IL) and tibialis anterior (TA), were recorded using an EMG measurement system. The test was performed by conducting dynamic squats with slope-WBV using frequency (10Hz, 50Hz), amplitude (0.5mm), and degree ($0^{\circ}$, $5^{\circ}$). Experimental method consisted of 2-pre-sessions and 1-test-session for 20 seconds. Results : The results showed that the muscle activities of the trunk and low limb muscles increased significantly with the $5^{\circ}$ slope and lower frequency (10Hz) except for in the TA. From this result, we confirmed that the slope and WBV could efficiently affect stimulation, enhancing muscle activities by facilitating neural control trail and muscle chain tightness. Conclusion : Utilizing the slope-WBV device while squatting could give positive effects on muscle activation in the trunk and lower limb muscles and provide neural stimulation, enhancing muscle chain of control subsystem through TVR (tonic vibration reflex).

• The Korean Journal of Physiology
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• 제3권1호
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• pp.33-44
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• 1969

Electoromyographic studies were performed on the action of the muscles of the temporomandibular joints following exfoliation of the deciduous teeth. The subjects examined, being 50 children. between the age of 6 and 13 years, divided into 5 groups. They were; 1) Deciduous dentition were complete in the first group. 2) Deciduous incisors were missing in either upper or lower jaw in the second group. 3) Deciduous canine and molars were missing in the left side of either upper or lower jaw in the third group. 4) Deciduous canine and molars were missing in the right side of either upper or lower jaw in the fourth group. 5) Permanent dentition completed in the fifth group(except third molars). Electromyogram was recorded with 4 channel polygraph (Grass model VII modified for 7P3). Electrodes which were the cup-typed gold discs, 9 millimeters in the diameter, were located on the anterior, middle and posterior lobes of the temporal muscles, and also on the superficial and deep layers of the masseter muscles. Paired electrodes were held by electrode cream so that they were pressed on the skin surface at right angle, adhesive tape being used to anchor them. The distance of the pair electrodes was about 5 millimeters. The results obtained were as follow: 1) In rest position of mandible; All groups showed slight, electrical activities in the muscles involved, but in the middle lobe of temporal muscle they were slightly higher. 2) In molar occlusion of mandible; High activity-anterior lobe of temporal muscle and superficial layer of masseter muscle. Moderate activity-deep layer of masseter muscle. Low activity-middle and posterior lobes of masseter muscle. There were no differences among the first, the second and the fifth groups. In the third group the muscle activity was weaker than that of the right, and in the fourth group opposite characteristics was revealed. 3) In incisal bite of mandreble; Hight activity-superficial layer of masseter muscle. Modertae activity-deep layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. The first, the third, the fourth and the fifth groups showed no differences but the second group showed less activity than those of others. 4) In protrusion of mandible; High activity-deep layer of masseter muscle Moderate activity-superficial layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. In the first, the fourth and the fifth groups, there were no differences in the activities, but the second group showed less activity than the others. 5) In retrusion of mandible; High activity-deep layer of masseter muscle. Moderate activity-superficial layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. In the first, the third, the fourth and the fifth groups, there were no differences but the second group showed less activity than the others. 6) In lateral excursion of the mandible (either direction); High activity-posterior lobe of temporal muscle. Moderate activity-anterior and middle lobes of temporal muscle. Low activity-superficial and deep layers of masseter muscle. The muscle action potentials were weaker than those of the right side in the third group and vice ver'sa in the fourth group. 7) In chewing movement; Temporal muscle activities were higher than those of masseter, especially in the middle lobe of temporal muscle the activity was highest. Right side muscle activities were higher than those of the left in the third group and, on the contrary, the left side was dominant over the right in the fourth group.

• 한국식품과학회지
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• 제18권3호
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• pp.173-180
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• 1986

근섬유의 생화학적 특성을 규명하기 위하여 red muscle과 white muscle로 부터 myofibril과 actomyosin을 각각 조제하고 그 생물활성 및 SDS-polyacrylamide gel전기 영동상을 비교하였다. 또한 동물의 중류에 따른 특성의 차이를 알아보기 위하여 소의 근육과 닭의 근육을 비교하였다. Myofibril의 SDS-polyacrylamide gel 전기 영동상으로 부터 red muscle은 white muscle보다 30K성분의 함량이 높다는 사실을 알았다. 소의 근육과 닭의 근육은 actomyosin ATPase활성의 이온강도의존성 및 ATPase activity-pH curve에서 차이를 보였다.

• 한국운동역학회지
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• 제15권2호
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• pp.155-165
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• 2005

The purpose of this study was to compare the muscle activities of Double Legged Jump (DLJ) and Single Legged Jump (SLJ) by the normalization of muscle activity. Eight college students without the lower extremity injuries were selected as subjects for collecting EMG data of vastus medialis and gastrocnemius. The entire section of motion was established as eccentric and concentric contractions, and each of the contractions was divided into three sections with equal timing intervals, which becomes a total of 6 phases. The EMG data of each phase was integrated and normalized. The muscle activities of the vastus medialis for both eccentric and concentric contractions were significantly different between DLJ and SLJ(p<.05). The increase in overall muscle activity of SLJ was 33.6%. Approximately, there was an increase of 25.9% in eccentric contraction and 40% in concentric contraction. Moreover, the data of the muscle activity of gastrocnemius was similar to the data of the muscle activity of vastus medialis. In conclusion, this research suggests muscle activity of a certain motion can be normalized for an analysis of another motion.

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1194-1201
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• 2004

Michael addition of certain nucleophiles on ${\alpha}$ , ${\beta}$-unsaturated ketones 1 led to the formation of adducts 2-7 as well as the reaction of arylidene derivatives with secondary amines afforded the amino compounds 9 and 11. Also, dialkylmalonates were treated with ${\alpha}$-cyano cinnamide to afford 13. On the other hand, double Michael cycloaddition of ethylcyanoacetate or tetrachlorophthalic anhydride to the suitable divinylketone were synthesized to produce 15-17. Selected compounds (13 and 6) were screened for muscle relaxant, anticonvulsant, and sedative activities using established pharmacological models. Their activities were compared with that of phenobarbital sodium taken as standard. Compound 6 was the most potent muscle relaxant while compounds 13a and 13c offered the highest anticonvulsant activity. Meanwhile compound 13c showed the highest potentiation of phenobarbital induced sleep in mice.