• 재활복지공학회논문지
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• 제10권1호
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• pp.47-57
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• 2016

본 연구에서는 다자유도 동적 하네스 시스템을 개발하고 동적 하네스 체중지지에 따른 인체 영향평가를 하고자 한다. 건강한 성인 남성 20명을 대상으로 실험을 진행하였으며 평지보행, 앉기, 서기, 계단 오르기, 계단 내려오기 5가지 일상생활 동작을 수행하였다. 일상생활 동작 수행 시 각 피험자 체중의 0%, 30%, 50%에서의 근육 활성도와 족압 분포를 측정하였다. 근육 측정부위는 대퇴직근, 대퇴이두근, 전경골근, 외측 비복근이다. 하네스 체중지지율 증가에 따라 족압의 평균값은 전체적으로 감소하는 경향을 보였다. 평지보행에서는 체중지지율 증가에 따른 전족부의 압력의 감소폭이 크게 나타났으며 비복근과 대퇴이두근의 활성 감소를 보였다. 앉기 동작에서는 후족부의 족저 압력 감소폭이 크게 나타났으며 체중지지율에 따라 전경골근의 근육 활성이 감소하였다. 계단 내려오기 동작에서는 체중지지율 증가에 따라 전족부의 압력이 크게 감소하였고 대퇴직근의 활성감소가 크게 나타났다. 의자에서 일어나기동작과 계단 오르기 동작에서는 동적 하네스 체중지지효과가 미비하였으며 이는 속도가 건강한 성인 남성의 동작 수행 속도보다 느리기 때문이다. 후속 연구에서는 본 시스템을 개선하기 위한 연구가 지속되어져야 할 것이다.

• 한국운동역학회지
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• 제31권4호
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• pp.308-313
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• 2021

Objective: The purpose of this study was to investigate the effect of different kettlebell mass (30%, 40%, and 50% of the body mass) on kinematics and kinetic variables of kettlebell swing. Method: Total of 16 healthy male who had at least 1 year of kettlebell training experience were participated in this study (age: 31.69 ± 3.46 yrd., height: 173.38 ± 4.84 cm, body mass: 74.53 ± 6.45 kg). In this study, a 13-segments whole-body model (upper trunk, lower trunk, pelvis, both side of forearm, upperarm, thigh, and shank) was used and 26 reflective markers were attached to the body to identify the segments during the movement. A 3-dimensional motion analysis with 8 infrared cameras and 4 channeled EMG was performed to find the effect of kettlebell mass on its swing. To verify the kettlebell mass effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at 𝛼=.05. Results: Firstly, in all lower extremity joints and thoracic vertebrae, a statistically significant change in angle was shown according to an increase in kettlebell mass during kettlebell swing (p<.05). Secondly, in both the up-swing and down-swing phases, the knee joint and ankle joint ROM showed a statistically significant increase as the kettlebell mass increased (p<.05) but no statistically significant difference was found in the hip joint and thoracic spine (p>.05). Lastly, the hamstrings muscle activity was statistically significantly increased as the kettlebell mass increased during up-swing phases (p<.05). Also, as the kettlebell mass increased in P4 of the down swing phase, the gluteus maximus showed a statistically significantly increased muscle activation, whereas the rectus femoris showed a statistically significantly decreased muscle activation (p <.05). Conclusion: As a result of this study, hip extension decreased and knee extension increased at 40% and 50% of body mass, and the spine also failed to maintain neutrality and increased flexion. Also, when kettlebell swings are performed with 50% of body mass, synergistic muscle dominance appears over 30% and 40% of body mass, which is judged to have a risk of potential injury. Therefore, it is thought that for beginners who start kettlebell exercise, swing practice should be performed with 30% of body mass. In addition, even in the case of experienced seniors, as the weight increases, the potential injury risk may increase, so it is thought that caution should be exercised when performing swings with 40% and 50% of body mass. In conclusion, it is thought that increasing the weight after sufficiently training with 30% of the weight of all subjects performing kettlebell swing is a way to maximize the exercise effect as well as prevent injury.

• 척추신경추나의학회지
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• 제2권1호
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• pp.69-75
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• 2007

Objectives : This study was performed to find the correlation between moire topography and muscle development ratio of both lower limbs. Methods : 88-general persons who examed general health checkup were enrolled this study. Who coincided the exclusion criteria were left out. The authors practiced Moire Topography by using IBS-2000 and measured difference of contour line and interval between vertical base line of neck and pelvis. We made use of X-SCAN to analyse body component and calculate muscle development ratio of both lower limbs. Results : In this study, we found out that the more interval between vertical base line of neck and pelvis grown large, the more muscle development ratio of both lower limbs got small. So, there was correlation between imbalance of the dorsum muscle and muscle development ratio of both lower limbs.(p>0.05). But others did not have. Conclusion : According to this results, we found out there was correlation between imbalance of lumbar and gluteal region and muscle development ratio of both lower limbs. Apply to clinic, we are able to improve the efficacy of diagnosis and medical treatment.

• Asian-Australasian Journal of Animal Sciences
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• 제20권12호
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• pp.1865-1873
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• 2007

An experiment was performed to evaluate the effects of dietary metabolizable energy (ME) and lysine on carcass characteristics and meat quality in Arbor Acres (AA) broilers from 1 to 56 days of age. A total of 2,970 1-d-old male broiler chicks were randomly allocated to nine dietary treatments (three ME levels in combination with three lysine levels), and dietary ME and lysine concentrations were formulated by varying corn, soybean meal, tallow, and L-lysine sulfate concentrations. Live body weight (BW), carcass weight (CW), dressing percent, breast muscle weight (BMW), yield of breast muscle, muscle color (CIE L*, a*, and b*), pH values 45 min and 24 h postmortem ($pH_{45}$, and $pH_{24}$), meat shear force value (SFV), and water loss rate (WLR) were evaluated. Results showed that live body weight and dressing percent increased (p<0.05) as dietary energy increased. Higher dietary lysine content improved breast muscle weight. Neither carcass weight nor yield of breast muscle was affected by dietary energy or lysine content. Higher ME increased the b* value (p = 0.067) and $pH_{24}$ value (p<0.05), whereas it decreased SFV (p<0.05) and WLR (p = 0.06). Only water loss rate was influenced (p<0.01) by dietary lysine, which was higher in broilers from the high lysine diet as compared to those from medium or low lysine diets. The $pH_{45}$ value and L* value of breast muscle were not affected by ME or lysine. Significant interaction of dietary ME and lysine was found on a* value of breast muscle. These results indicated that dietary ME and lysine had important effects on breast muscle growth and meat quality, however their effects were different. Different concentrations of dietary ME and lysine might be considered to improve meat quality.

• 한국정밀공학회지
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• 제27권2호
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• pp.130-136
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• 2010

For stability analysis of the lumbar spine, the hypothesis presented is that the disc has stress sensors driving feedback mechanism, which could react to the imposed loads by adjusting the contraction of the muscles. Fusion in the motion segment of the lumbar spinal column is believed to alter the stability of the spinal column. To identify this effect finite element (FE) models combined with optimization technique was applied and quantify the role of each muscle and reaction forces in the spinal column with respect to the fusion level. The musculoskeletal FE model was consisted with detailed whole lumbar spine, pelvis, sacrum, coccyx and simplified trunk model. Vertebral body and pelvis were modeled as a rigid body and the rib cage was constructed with rigid truss element for the computational efficiency. Spinal fusion model was applied to L3-L4, L4-L5, L5-S1 (single level) and L3-L5 (two levels) segments. Muscle architecture with 46 local muscles was used as acting directions. Minimization of the nucleus pressure deviation and annulus fiber average axial stress deviation was selected for cost function. As a result, spinal fusion produced reaction changes at each motion segment as well as contribution of each muscle. Longissimus thoracis and psoas major muscle showed dramatic changes for the cases of L5-S1 and L3-L5 level fusion. Muscle force change at each muscle also generated relatively high nucleus pressure not only at the adjacent level but at another level, which can explain disc degeneration pattern observed in clinical study.

• Journal of Ginseng Research
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• 제46권3호
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• pp.454-463
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• 2022

Background: Gintonin-enriched fraction (GEF), a non-saponin fraction of ginseng, is a novel glycolipoprotein rich in hydrophobic amino acids. GEF has recently been shown to regulate lipid metabolism and browning in adipocytes; however, the mechanisms underlying its effects on energy metabolism and whether it affects sarcopenic obesity are unclear. We aimed to evaluate the effects of GEF on skeletal muscle atrophy in high-fat diet (HFD)-induced obese mice. Methods: To examine the effect of GEF on sarcopenic obesity, 4-week-old male ICR mice were used. The mice were divided into four groups: chow diet (CD), HFD, HFD supplemented with 50 mg/kg/day GEF, or 150 mg/kg/day GEF for 6 weeks. We analyzed body mass gain and grip strength, histological staining, western blot analysis, and immunofluorescence to quantify changes in sarcopenic obesity-related factors. Results: GEF inhibited body mass gain while HFD-fed mice gained 22.7 ± 2.0 g, whereas GEF-treated mice gained 14.3 ± 1.2 g for GEF50 and 11.8 ± 1.6 g for GEF150 by downregulating adipogenesis and inducing lipolysis and browning in white adipose tissue (WAT). GEF also enhanced mitochondrial biogenesis threefold in skeletal muscle. Furthermore, GEF-treated skeletal muscle exhibited decreased expression of muscle-specific atrophic genes, and promoted myogenic differentiation and increased muscle mass and strength in a dose-dependent manner (p < 0.05). Conclusion: These findings indicate that GEF may have potential uses in preventing sarcopenic obesity by promoting energy expenditure and attenuating skeletal muscle atrophy.

• 대한통합의학회지
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• 제11권1호
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• pp.63-70
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• 2023

Purpose : Excessive alcohol causes damage to skeletal muscles, leading to the development of a specific disease entity called alcoholic myopathy. Chronic inflammation is related as an underlying mechanism for the loss of muscle mass induced by alcohol. Pro-inflammatory cytokines such as TNF-α (tumor necrosis factor-α) and IL-6 (interleukin-6) play a role in this process. The acupuncture point Feng Shi (GB 31) is located on the midline of the lateral aspect of the thigh, above the transverse popliteal crease. This acupoint is used for the treatment of weakness, atrophy, numbness, and post-stroke symptoms of lower limbs. The purpose of this study was to investigate the effect of Feng Shi stimulation on muscle atrophy caused by chronic alcohol administration. Method : Young male Sprague-Dawley rats were randomly divided into three groups of eight each: Normal, Control, and GB31. The rats in the Control and GB31 groups were orally given 25 % ethanol (5 ㎖/kg, body weight) daily for 4 weeks. The Normal group was similarly administered saline. The acupressure at Feng Shi was treated to rats in the GB31 group. After 4 weeks, the body weight, muscle weight and cross-sectional area of gastrocnemius were assessed and the histological changes in gastrocnemius muscle fiber were observed by hematoxylin and eosin staining. Moreover, TNF-α and IL-6 expressions were immunohistochemistrically evaluated. Results : Acupressure stimulation at Feng Shi had a protective effect on the weight reduction of the gastrocnemius muscle caused by alcohol intake, and had an effect of suppressing anatomical change in muscle fiber and decreasing the average cross-sectional area. Also, the immunoreactivities of TNF-α and IL-6 in the GB31 group were decreased. Conclusion : These results suggest that acupressure at Feng Shi has protective effects on chronic alcohol-induced muscle atrophy by inhibiting pre-inflammatory proteins such as TNF-α and IL-6.

• 대한임상전기생리학회지
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• 제1권2호
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• pp.21-30
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• 2003

The purpose of this study was to know the effect of aquatic-exercise on muscle atrophy which induced by steroid injection. The forty-eight Sparague-Dawley adult male rats were assigned to the 4 groups; GroupI(distilled water injection), GroupII(steroid injection), GroupIII(distilled water injection and aquatic exercise), GroupIV(steroid injection and aquatic exercise). We observed their body weight, histological change by PAS stein. The results of this study were as follows; 1. After 2 weeks, the change of weights appeared that non-steroid injection groups increase weight and steroid injection groups decreased weight hasty. after 4 weeks, weights recovered from weight before test. It was possible to explain the change of weight by type II muscle fiber increase. 2. In histological change of muscle fibers, atrophy didn't observed in test group I, because type II muscle fibers were developed well. we observed not only injury of muscle fiber and muscle atrophy but specifically grouping type I muscle fiber in test group II. normal arrangement of muscle fibers were visible in test group and type II muscle fibers increased. we could observe muscle recovery because of type II muscle fibers increase in test group IV. therefore, it was seem that type II cell was recovering through aquatic exercise.

• 한국응용과학기술학회지
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• 제36권4호
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• pp.1164-1171
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• 2019

Dietary supplements derived from natural sources are an essential factor in optimizing athletic performance. It has been proposed that the extract of Momordica charantia (M. charantia) that is known as a bitter melon can be potentially used as a novel supplement for health promotion. This pilot study aimed to examine the effects of the M. charantia extract when administered in the form of a sports drink, and we evaluated changes in body composition and metabolic factors in tennis players after 4-week consumption of the extract. Eight male college tennis players were instructed to consume an M. charantia extract 6 times per day (3 in the morning and 3 in the afternoon, and the total daily intake was 600 ml). Collected data were analyzed using paired t-tests to examine the changes over time after consumption of the M. charantia extract. The results revealed a significant increase in the trunk muscle mass, basal metabolic rate, and daily calorie intake (p < 0.05). Levels of protein, minerals, and total body water showed an increased tendency (not statistically significant), whereas intracellular water and extracellular water showed a decreased trend. Furthermore, fat-free mass, skeletal muscle mass, and muscle mass showed an increased tendency. In conclusion, consumption of the M. charantia extract caused an increase in parameters related to protein, muscle mass, and metabolism. It seems that follow-up studies related to fatigue, inflammation, and stress hormones related to the M. charantia extract consumption would be needed.

• 대한기계학회논문집A
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• 제35권7호
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• pp.785-790
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• 2011

본 연구에서는 인체의 하지부를 다물체 시스템으로 모델링하여 무릎관절에 걸리는 구속력의 불확실성을 추정하였다. 일반적으로 근육의 기계적인 특성은 Hill-type muscle model 이 사용되며 여기에 적용되는 인체의 특성과 해부학적인 데이터는 지난 십 수년 동안 크게 발전되었다. 그러나 정확하게 그것들을 안다는 것은 불가능하며 개인마다 다른점을 고려해야 할 필요가 있다. 본 논문에서는 Hill-type muscle model 과 함께 인체의 해부학적인 데이터를 통계 방법론을 이용하여 무릎 관절에 걸리는 구속력의 불확실성을 추정하였다. 초기 앉아있는 자세에서 일어서는 과정에서 작용하는 구속력을 추정하였으며 이때 인체 하지 근육의 특성을 musculoskeleton-actuator 를 이용하여 해석하였다.