• The Journal of Korean Physical Therapy
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• v.26 no.3
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• pp.156-162
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• 2014

Purpose: The purpose of this study was to investigate muscle activation related to postural stability depending on different head positions with whole body vibration (WBV) in standing. Methods: Eighteen healthy subjects voluntarily participated in this single-group, repeated-measures study in which the surface electromyography (EMG) data from upper trapezius, rectus abdominis, external oblique abdominis, erector spinae, gluteus maximus, rectus femoris, semitendinosus, medial gastrocnemius were collected over 3 different frequencies (0-10-20Hz) and 4 different head positions (neutral, flexion, extension, chin tuck) for each subject on WBV while standing. Results: The results of this study demonstrated that the EMG activity of all recorded muscles shows significant difference between three different frequencies and four head positions of WBV while standing (p<0.05). In the multiple comparison, significant differences could be observed for most of different frequency conditions except 0-10Hz of RA, 10-20Hz of ST. In contrast, no significant difference showed the comparison of the EMG activity depending on different head positions (p<0.05). Conclusion: These findings suggest that different head positions on WBV do not activate muscles related to postural stability. However, higher frequency on WBV is highly effective to activate whole body muscles included postural muscles regardless of different head positions.

• Physical Therapy Rehabilitation Science
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• v.8 no.1
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• pp.45-51
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• 2019

Objective: The purpose of this study was to investigate the muscle activity ratio of the lower limb according to changes in straight leg raise (SLR) test angles on hamstring muscle shortening during squat exercises. Design: Randomized controlled trial. Methods: The subjects were 14 healthy adults who were informed of and agreed to the method and purpose of the study. The participants were classified into SLR groups according to two angles (over $80^{\circ}$ or under $80^{\circ}$) assessed using the SLR tests. After training and practicing the wall squat posture to be applied to the experiment, electromyography (EMG) was used to measure changes in muscle activity during the performance of a wall squat. After stretching, a sequence of pre-stretch tests were performed again, and the active and passive SLR tests were also reconducted; thereafter, a wall squat was performed again by attaching EMG electrodes. The EMG results before and after stretching were compared. Results: The muscle activity of the vastus lateralis oblique muscle increased in both groups. The muscle activity of the vastus medialis oblique muscle decreased in over both group. Rectus femorus activity increased in the under 80-degree groups but decreased in the over 80-degree group. The muscle activity of the biceps femoris muscle decreased after stretching in the over 80-degree group and increased in the under 80-degree group, and the semitendinosus muscle activity after stretching was decreased. The quadriceps-to-hamstring muscle (Q:H) ratio before and after stretching between groups showed that the hamstring muscle ratio decreased after stretching in both groups. Conclusions: The results of this study showed that the Q:H ratio before and after stretching between groups was not significantly different.

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.207-219
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• 2005

The purpose of this study was to determine the effect of the foot rotation on the lower limb muscles. Fourteen subjects performed step-up/step-down at a cadence of 80 beats/min, exercises with the foot neutral, $35^{\circ}$ internally rotated, and $35^{\circ}$ externally rotated, respectively. For each variable, a one-way analysis of variance (ANOVA) was used to determine whether there were significant differences between genders and among the eight types of jump. When a significant difference was found in jump type, post hoc analyses were performed using the Tukey procedure. A confidence level of p < .05 was used to determine statistical significance. The results showed that significant changes in averaged IEMG values occurred with the internal rotation of the foot in the lateral gastrocnemius during the knee extension, and in the semitendinosus during the knee flexion. During the knee extension, however, the internal rotation of the foot produced a significantly lower Averaged IEMG values than the neutral foot position in the medial gastrocnemius. The results also found that the peak IEMG activity of the rectus femoris during the knee extension for the external rotation of the foot was Significantly higher than the corresponding values in the neutral position of the foot, while the intenal rotaion of the foot exhibited a significant difference with the neutral position of the foot in the semitendinosus during the knee flexion. In general, the foot rotation position did not influence the average IEMG and Peak IEMG values of most muscles. The practice of adopting foot rotation to selectively strengthen individual muscles of the lower limb was not supported by this study. The external rotation of the foot produced high muscle activities in the quadriceps during the knee extension. For the knee extension, therefore, maintaining a laterally rotated position should be need for stable and comfortable position.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.665-671
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• 1999

Post mortem bovine muscle. semitendinosus was used to investigate the effects of gamma irradiation on physicochemical properties. The muscle was cut into pieces of 2 cm in thickness and packaged with 2 different methods; vacuum-packaged and air-packaged. The packaged samples were irradiated at designated doses of 0, 1, 3 and 5 kGy by Cobalt-60 irradiator. Muscle protein solubility, purge loss, composition and contents of free amino acids, and shear force were observed during storage at $4^{\circ}C$. We found no significant differences in the purge loss and the contents of free amino acids. Muscle protein solubility slightly increased depending upon the increase of the dose. The decrease of shear force by gamma irradiation was observed. Therefore, it is considered that meat quality can be improved by gamma irradiation.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1345-1357
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• 2018

Objective: This study examined the influence of dietary supplementation of Nigella sativa seeds, Rosmarinus officinalis leaves and their combination on carcass attributes, fatty acid (FA) composition, gene expression, lipid oxidation and physicochemical properties of longissimus dorsi (LD), semitendinosus (ST), and supraspinatus (SS) muscles in Dorper lambs. Methods: Twenty-four Dorper lambs ($18.68{\pm}0.6kg$, 4 to 5 months old) were randomly assigned to a concentrate mixture containing either, no supplement (control, T1), 1% Rosmarinus officinalis leaves (T2), 1% Nigella sativa seeds (T3), or 1% Rosmarinus officinalis leaves+1% Nigella sativa seeds (T4) on a dry matter basis. The lambs were fed the treatments with urea-treated rice straw for 90 days, slaughtered and the muscles were subjected to a 7 d postmortem chill storage. Results: The T2 lambs had greater (p<0.05) slaughter and cold carcass weights than the control lambs. Dietary supplements did not affect (p>0.05) chill loss, dressing percentage, carcass composition, intramuscular fat and muscle pH in Dorper lambs. Meat from supplemented lambs had lower (p<0.05) cooking and drip losses, shear force, lightness, and lipid oxidation and greater (p<0.05) redness compared with the control meat. The impact of dietary supplements on muscle FA varied with muscle type. Diet had no effect (p>0.05) on the expression of stearoyl-CoA desaturase and lipoprotein lipase genes in LD and ST muscles in Dorper lambs. The T2 and T3 diets up regulated the expression of AMP-activated protein kinase alpha 2 gene in LD and ST muscles and up regulated the expression of sterol regulatory element-binding protein 1 in ST muscle in Dorper lambs. Conclusion: Dietary supplementation of Nigella sativa seeds and Rosmarinus officinalis leaves had beneficial effects on meat quality in Dorper lambs.

• Korean Journal of Applied Biomechanics
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• v.29 no.2
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• pp.105-112
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• 2019

Objective: The main purpose of this study was to investigate the effects of wearing an ankle weight belt while performing gait in water by focusing on the effect of using ankle weights have on the gait kinematics and the muscle activities for developing optimum training strategies. Method: A total of 10 healthy male university students were recruited for the study. Each participant was instructed to perform 3 gait conditions; normal walking over ground, walking in water chest height, and walking in water chest height while using ankle weights. All walking conditions were set at control speed of $4km/h{\pm}0.05km/h$. The depth of the swimming pool was at 1.3 m, approximately chest height. The motion capture data was recorded using 6 digital cameras and the EMG was recorded using waterproof Mini Wave. From the motion capture data, the following variables were calculated for analysis; double and single support phase (s), swing phase (s), step length (%height), step rate (m/s), ankle, knee, and hip joint angles ($^{\circ}$). From the electromyography the %RVC of the lower limb muscles medial gastrocnemius, rectus femoris, erector spinae, semitendinosus, tibialis anterior, vastus lateralis oblique was calculated. Results: The results show significant differences between the gait time, and step length between the right and left leg. Additionally, the joint angular velocities and gait velocity were significantly affected by the water resistance. As expected, the use of the ankle weights increased all of the lower leg maximum muscle activities except for the lower back muscle. Conclusion: In conclusion, the ankle weights can be shown to stimulate more muscle activity during walking in chest height water and therefore, may be useful for rehabilitation purposes.

• PNF and Movement
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• v.11 no.2
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• pp.111-117
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• 2013

Purpose : The purpose of this study was to examine the activity of the knee flexor and extensor with ankle plantar flexion and dorsiflexion. Methods : A total of 18 subjects(Male 6, female 12) performed 4 lower extremity patterns of PNF and the activities of the vastus medialis oblique, rectus femoris, vastus lateralis, biceps femoris, semitendinosus ipsilateral sides were measured using electromyography. Results : During 4 lower extremity patterns of PNF, knee flexor and extensor muscle activity were significantly difference. Knee extensors were shown to be higher knee extension and ankle dorsiflexion combined pattern. Knee flexors were shown to be higher knee flexion and ankle plantarflexion combined pattern. Conclusion : We suggest that it is efficient to strengthening of knee extensors with ankle dorsiflexion and to strengthening of knee flexors with ankle plantar flexion. Also, for the functioning as toe standing, we have to choice appropriate movement pattern.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.4
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• pp.223-230
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• 2020

Purpose : The purpose of this study was to examine the effects of tools (i., extracorporeal shock wave therapy, massage gun, and foam roller) on range of motion, muscle tone and pain threshold among patients with hamstring stiffness. Methods : Fourteen participants with hamstrings stiffness were recruited. Interventions were performed 6 times, and each session was for 30 seconds using the three tools. The range of motion, muscle tone, and pain threshold were measured. The order of the use of the three tools was randomly determined. The foam roller was made to move from the bottom of the hip crease to the upper part of the back of the hamstring. Additionally, velocity 5 vibration stimulation was performed on the hamstring using a massage gun. Moreover, vibration stimulation was performed on the hamstring with extracorporeal shock wave therapy 5 minutes, 5 Hz, and 1,500 strokes. The flexibility of the posterior thigh muscle was based on maintaining the knee and hip joints in a 90 ° bend in the supine position. The joint angle of the knee was measured, when the knee was actively extended, at the maximum point where the posterior thigh muscle was stretched. The elasticity of the posterior thigh muscle was measured while the subject was prone and in a relaxed state without any force. Measurements were made at the muscle abdominal area of the semitendinosus muscle of the posterior femur, and the area to be measured was marked with a pen. The measurement of the tenderness threshold of the posterior femur was measured using a tenderness meter(Commander Algometer, J-Tech, USA). The force value at the point at which the pressure sensation change to pain was measured after applying vertical pressure to the posterior femur muscle, which was the halfway point between the ischial tuberosity and the popliteal surface of the subject lying on their stomach. Results : The extracorporeal shock wave therapy increased stiffness and, muscle tone, and caused changes in the pain threshold, whereas the other two tools had no effect on these indices. Conclusion : Extracorporeal shock wave therapy has important effects on range of motion and muscle stiffness and can be used in warmup protocols.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.757-762
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• 2013

This study was conducted to develop a processing method for dry-curing beef ham with Korean traditional sauces and to investigate the quality properties of the dry-cured beef hams. Semitendinosus muscle from Hanwoo was spread with sundried salt (C), sun-dried salt mixed with red pepper paste (T1), and sun-dried salt mixed with soybean paste (T2), and inserted into washed Hanwoo large intestine. It was then dried and fermented for 75 d. Moisture contents of the hams were 46-48%, without any significant differences. T1 showed the lowest pH among the three dry-cured hams, while water holding capacity (WHC) of T2 was found the lowest (p<0.05). In mechanical color determination, C showed higher CIE $a^*$ and CIE $b^*$ than T1 and T2 (p<0.05), however CIE $L^*$ did not show any significant difference. In texture, T1 demonstrated significantly lower springiness than C (p<0.05). The sensory properties of all dry-cured hams did not show any significant difference, but T1 indicated a higher taste, saltiness and overall acceptability than others, whereas C gathered the highest score in color and flavor. In conclusion, the dry-curing by combination of sun-dried salt mixed with red pepper sauce (T1) showed higher quality properties of the Hanwoo dry-cured ham.

• Food Science of Animal Resources
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• v.26 no.3
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• pp.362-367
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• 2006

This study was conducted to evaluate the feasibility of determination of hydroxyproline (Hyp) contents in pork meat for the quality evaluation of meat products. The relationship between the Hyp contents and pork grade was not high in porcine semitendinosus muscle. Whereas, Hyp contents of pork fresh ham and hamburger patties prepared with them were significantly increased as the decrease of pork grade. These results showed that the determination of Hyp contents might be a useful method for the quality evaluation of meat products.