Background: High-heeled shoes can change spinal alignment and feet movement, which leads to muscle fatigue and discomfort in lumbopelvic region, legs, and feet while walking. Objects: This study aimed to identify the effects of different shoe heel heights on the walking velocity and electromyographic (EMG) activities of the lower leg muscles during short- and long-distance walking in young females. Methods: Fifteen young females were recruited in this study. The experiments were performed with the following two different shoe heel heights: 0 ㎝ and 7 ㎝. All participants underwent an electromyographic procedure to measure the activities and fatigue levels of the tibialis anterior (TA), medial gastrocnemius (MG), rectus femoris (RF), and hamstring muscles with each heel height during both short- and long-distance walking. The walking velocities were measured using the short-distance (10-m walk) and long-distance (6-min walk) walking tests. Results: Significant interaction effects were found between heel height and walking distance conditions for the EMG activities and fatigue levels of TA and MG muscles, and walking velocity (p<.05). The walking velocity and activities of the TA, MG, and RF muscles appeared to be significantly different between the 0 ㎝ and 7 ㎝ heel heights during both short- and long-distance walking (p<.05). Significant difference in the fatigue level of the MG muscle were found between the 0 ㎝ and 7 ㎝ heel heights during long-distance walking. In addition, walking velocity and the fatigue level of the MG muscle at the 7 ㎝ heel height revealed significant differences in the comparison of short- and long-distance walking (p<.05). Conclusion: These findings indicate that higher shoe heel height leads to a decrease in the walking velocity and an increase in the activity and fatigue level of the lower leg muscles, particularly during long-distance walking.

Background: Chronic low back pain (CLBP) causes morphological changes in muscles, reduces muscle strength, endurance and flexibility, negatively affects lumbar stability, and limits functional activity. Plank exercise strengthens core muscles, activates abdominal muscles, and improves intra-abdominal pressure to stabilize the trunk in patients with CLBP. Objects: We investigated the effect of plank exercise on abdominal muscle thickness and disability in patients with CLBP. Methods: We classified 33 subjects into 2 groups: An experimental (n1=17) and a control group (n2=16). Patients in the experimental group participated in plank exercise and those in the control group participated in stretching exercise. Patients in both groups attended 20-minute exercise sessions thrice a week for 4 weeks. Abdominal muscle thickness in each subject was evaluated ultrasonographically, and disabilities were assessed using the Oswestry disability index (ODI). Results: Four weeks later, abdominal muscle thickness showed a significant increase over baseline values in both groups (p<.05). Patients in the experimental group reported a more significant increase in the thickness of the external oblique muscle than that in the control group (p<.05). ODI scores in the experimental group were significantly lower after intervention than before intervention (p<.05). Conclusion: Plank exercise increases the thickness of the external oblique muscle and reduces disability secondary to mild CLBP. Therefore, plank exercise is needed to improve lumbar stability and functional activity in patients with mild CLBP.

In this study, the characteristics of muscle relaxation were analyzed by the experimental and numerical method. A skin tissue was produced by imitational biological tissue using the agar powder, saline solution and sugar. The tissue was exposed to three types of wavelength-blue visible radiation(410 nm), red visible radiation(635 nm), and infrared ray(830 nm). The temperature results along the depth of tissue were measured according to the variation of light wavelength and irradiation time. The temperature change of the tissue shown up similar pattern regardless of the light wavelength kinds. The wavelength of infrared ray penetrated strongly into tissue between 3.2 mm and 11.4 mm. Also, the temperature change with the irradiation time was small, and the temperature value of the infrared ray was the largest. As a result, the muscle relaxation will occur mainly at the infrared wavelength.

This study suggests a new perspective for designing men’s tailored jackets by more carefully considering human muscle structure. For this study, we examined research regarding the construction of the tailored jacket that is based on costume history references, as well as research regarding human muscle structure that is based on human anatomy references and the analysis of recent fashion designs illustrating the human body image. Based on this research, we developed various tailored constructions that account for human muscle structure. These constructions are applied primarily to the backs of four tailored jackets, as the back of the jacket needs a mechanism to accommodate the wearer’s movement. The following conclusions have been derived from the study: First, by developing the tailored garment structure that accounts for the muscle structure of the human body, we suggest a new design direction for tailored garments. Second, we propose a new type of tailored jacket structure for the back of the jacket that incorporates an artificial muscle structure to accommodate the wearer’s activities. This new type of jacket indicates the potential for designs that use structure, particularly the structure of the human body. Finally, by using the embroidery technique, we changed the texture of the material into the shape of human muscle. Thus, we propose a design that uses three-dimensional volume to accounts for the shape of human body tissue.

Whole body fatigue detection is an important phenomenon and the factors contributing to whole body fatigue can be controlled if a mathematical model is available for its assessment. This research study aims at developing a model that categorizes whole body exertion into fatigued and non-fatigued states based on physiological and perceived variables. For this purpose, logistic regression was used to categorize the fatigued and non-fatigued subject as dichotomous variable. Normalized mean power frequency of eight muscles from 25 subjects was taken as physiological variable along with the heart rate while Borg scale ratings were taken as perceived variables. The logit function was used to develop the logistic regression model. The coefficients of all the variables were found and significance level was checked. The detection accuracy of the model for fatigued and non-fatigues subjects was 83% and 95% respectively. It was observed that the mean power frequency of anterior deltoid and the Borg scale ratings of upper and lower extremities were significant in predicting the whole body fatigued when evaluated dichotomously (p < 0.05). The findings can help in better understanding of the importance of combined physiological and perceived exertion in designing the rest breaks for workers involved in squat lifting tasks in industrial as well as health sectors.

목적 : 본 연구는 저항운동으로 6주간 적용된 혀-유지 메뉴버 프로그램이 Shaker 운동 프로그램과 비교하여 정상성인의 삼킴 근육 활성도에 미치는 영향을 알아보고자 하였다. 연구방법 : 2015년 10월부터 12월까지 10대에서 50대의 건강한 성인 26명을 대상으로 혀-유지 메뉴버 그룹과 Shaker 운동 그룹으로 무작위 할당하여 주 5일, 하루 1회, 30분씩 6주간 적용하였다. 표면근전도를 사용하여 설골상근 (suprahyoid muscle)과 설골하근(infrahyoid muscle)에 대한 근활성도를 수집하였다. 시각적 비율척도(Visual Analog Scale), 자각인지 척도(Borg-Rating of Perceived Exertion Scale) 척도를 사용하여 삼킴 시 노력과 피로를 측정하였다. 결과 : 혀-유지 메뉴버 그룹과 Shaker 그룹 모두 설골상근과 설골하근의 근활성도가 유의한 향상을 보였지만, 두 그룹 간의 유의한 차이는 없었다. 또한 두 그룹 모두 삼킴 시 노력 및 피로가 통계학적으로 유의한 차이를 보였으나, 두 그룹 간의 유의한 차이는 없었다. 결론 : 건강한 성인을 대상으로 6주간 혀-유지 메뉴버를 통해 삼킴 근육 근활성도에 대한 긍정적인 효과를 확인하였다. 향후에는 삼킴장애 환자를 대상으로 혀-유지 메뉴버에 대한 임상적 효용성을 검증하여 유용한 치료기법으로 사용되기를 기대한다.

This study was conducted to investigate the effect of chronic alcohol supplementation on muscle atrophy in growing rats. Eighteen male Sprague Dawley rats were randomly divided into two groups: CG group (control group, n=9) and AG group (alcohol supplemented group, n=9). Alcohol group (3 g/kg BW) was orally supplemented every day. After the experimental period, serum components and muscle Akt, p-Akt, FoxO, p-FoxO, MuRF1, and P38 protein expressions were analyzed. In the results, the values of EDL and soleus muscle weights of AG group did not have significant differences compared to the value of the CG group. In the serum components, the value of the serum TG concentration of AG group was significantly increased compared to the value of the CG group. The value of the p-Akt/Akt and p-FoxO/FoxO of the AG group was significantly decreased compared to the value of the CG group (p<0.01). The MuRF1 protein expression of AG group was significantly increased compared to the value of the CG group (p<0.01). However, the values of p-P38/P38 between two groups did not have any significant difference. From these results, it was suggested that 4 weeks of chronic alcohol supplementation induced muscle atrophy via activated protein degradation pathway involving the inhibition of Akt phosphorylation and increased FoxO and MuRF1 protein expression of muscle in growing rats.

목적 : 본 연구는 베일리 영유아 발달검사 3판 대근육 운동척도를 한국판(Korean-Bayley-Ⅲ; K-Bayley-Ⅲ)으로 타당화하기 위하여 문항분석과 신뢰도 및 타당도를 검증하고자 하였다. 연구방법 : 본 연구의 참여자는 생후 16일에서 42개월 15일의 영유아 1,764명으로, 지역 및 성별, 모의 학력에 따라서 층화 표집되었다. 문항분석을 위하여 문항반응이론에 근거한 문항 난이도 분석과 고전검사이론을 통한 문항 통과율을 분석하였고, 신뢰도를 검증하기 위하여 반분신뢰도를 이용한 내적일관성, 검사-재검사 신뢰도, 평정자간 일치도를 살펴보았으며, 상호상관검증을 통해 수렴타당도와 변별타당도를 확인하였다. 결과 : 첫째, K-Bayley-Ⅲ 대근육 운동척도의 난이도를 조사한 결과, 총 72개의 문항은 원척도와 유사하게 쉬운 문항에서 어려운 문항까지 비교적 순차적으로 배치되어 있었다. 또한 시작점과 기저선 문항의 적절성을 알아보기 위하여 월령 단계별 문항 통과율을 확인한 결과, 대부분의 월령 단계에서 시작점과 기저선 문항이 적절한 것으로 나타났다. 둘째, 척도의 신뢰도 분석 결과, 대부분의 월령 단계에서 문항 내적일관성이 높은 것으로 나타났으며, 검사-재검사 신뢰도 및 평정자간 일치도도 높은 것으로 확인되었다. 마지막으로 타당도 검증 결과, 대근육 운동척도는 운동척도와는 높은 상호상관을 보인 반면 언어척도와는 중간 정도의 상호상관을 보여 수렴 및 변별타당도가 확보되었다. 결론 : 본 연구를 통해 K-Bayley-Ⅲ 대근육 운동척도가 한국 영유아의 대근육 운동발달을 평가하는데 타당하고 신뢰로운 척도임이 입증되었다.

Background: Improvement of lumbo-pelvic stability can reduce the compensatory action of the quadratus lumborum (QL) and selectively strengthen the gluteus medius (GM) during side-lying hip abduction (SHA). There are abdominal draw-in maneuver (ADIM) and abdominal bracing (AB) as active ways, and pelvic compression belt (PCB) as a passive way to increase of lumbo-pelvic stability. It is necessary to compare how these stabilization methods affect the selective strengthening of the GM. Objects: To investigate the effects of ADIM, AB, and PCB during SHA on the electromyography (EMG) activity of the GM, QL, external oblique (EO) and internal oblique (IO), and the GM/QL EMG activity ratio. Methods: A total of 20 healthy male adults participated in the study. The subjects performed three conditions in side-lying in random order: SHA with ADIM (SHA-ADIM), SHA with AB (SHA-AB), and SHA with PCB (SHA-PCB). To compare the differences among the three conditions, the EMG activities of the GM, QL, EO and IO, and GM/QL EMG activity ratio were analyzed using one-way repeated ANOVA. Results: The EMG activity of the QL was significantly higher in SHA-AB than in SHA-ADIM and SHA-PCB. The GM/QL activity ratio was significantly higher in SHA-PCB than in SHA-ADIM and SHA-AB. In addition, the figure for SHA-ADIM was significantly higher than that for SHA-AB. In the case of the EO, the figure for SHA-AB was significantly higher than corresponding values for the other two conditions. The figure for SHA-ADIM was significantly higher than that for SHA-PCB. The EMG activity of the IO was significantly higher in SHA-AH than in SHA-PCB. Conclusion: It can be suggested that wearing the PCB can more selectively strengthen the GM than to perform ADIM and AB during SHA. In addition, the ADIM can be recommended when there is a need to strengthen abdominal muscles during SHA.

The objective of this experiment was to investigate amino acids and mineral compositions of the four major muscles (LD: longissimus dorsi, PM: psoas major, SM: semimembranosus, and GM: gluteus medius) from Korean native black goat (KNBG). Five uncastrated male KNBGs of 36 months of age were commercially slaughtered and the four muscles were sampled to determine concentrations of myoglobin, collagen, amino acids and minerals. There were significant differences (p<0.05) in myoglobin and collagen content among the four muscles. Myoglobin content of PM was significantly higher (p<0.05) than those of SM and GM. Collagen content of SM was significantly higher (p<0.05) than that of LD. There were significant differences (p<0.05) in cystine and leucine concentrations among the four muscles, and PM had the highest concentrations of the two amino acids compared to other muscles (p<0.05). Also, there were significant differences (p<0.05) in K, P, Mg and Fe contents among the four muscles from KNBG. PM had the highest mineral content while the lowest mineral content was observed in LD. In addition, Fe contents of PM and GM were higher than those of LD and SM (p<0.05). These results indicated that amino acids and mineral content vary considerably with the anatomical location of muscles of Korean native black goat.

This study investigated the stress-related metabolites and hormones in blood and compared the muscle structure to identify the reason for blood splash in Hanwoo beef. Five slaughter houses were selected based on the region (Seoul, Gimhae, Jungbu, Naju, and Goryung) and a previous blood splash record. In total, three-hundred eighty blood samples (n=380) and forty-two muscle tissues (n=42) of control and blood splash Hanwoo beef were collected during the slaughter process and beef grading. Blood metabolites were analyzed including glucose, lactate, creatinine, urea-N, and hormones such as cortisol and thyroxin. Muscle fiber, fiber bundle, and capillary wall thickness were measured under microscope. The concentrations of blood glucose, lactate, and urea-N were not significantly different between the control and the blood splash samples. Cortisol and thyroxin levels were not significantly different in both samples. In contrast, the creatinine level was significantly increased (p<0.05) in the blood splash samples. There were also no significant differences observed in muscle fiber, bundles, and capillary wall thickness between the control and the blood splash tissues. In conclusion, blood metabolites, hormones, and muscle fiber showed no differences between the control and the blood splash animal. However, increased creatinine levels may be used as an indicator for identifying blood splash prior to slaughter in Hanwoo.

악기를 능숙하게 연주하기 위해 구조와 기능을 아는 것은 매우 중요하다. 사람은 목소리를 악 기로 사용하지만, 목소리를 내는 기관은 만질 수 없고 눈에 보이지 않기 때문에 접근하기 어렵 다. 그래서 해부학적으로 접근해야만 구조를 알게 된다. 우리가 몸 안의 기관을 해부학적으로 정확하게 인식하는 것이 운동기능 향상에 영향을 준다. 이것을 ‘운동 감각’을 통해 증명한다. 공명과 턱관절 및 근육의 정의와 기능을 알고 ‘턱 근육의 올바른 사용’이 발성의 ‘공명’에 미치는 영향을 알았을 때 우리는 가창에 필요한 운동기능을 훈련할 수 있게 된다. 이 훈련을 통 해 턱 근육과 발성 기관을 인지하여 가창했을 때 부정적인 주변 환경, 심리상태와 상관없이 좋은 공명의 가창을 할 수 있도록 훈련할 수 있다. 또한, 추상적인 표현의 교수법 등으로 교사의 경험 이 학생에게 제대로 전달되지 못하는 경우가 많다. 발성 기관의 해부학적 접근을 통해 교사와 학생의 거리를 좁힐 수 있는 직접적이고 효과적인 교수법을 제시한다.

Background:To improve lumbo-pelvic stability, passive support devices (i.e., a pelvic belt) are recommended clinically. Nevertheless, to understand the influence of passive support on lumbo-pelvic stability, it is necessary to examine the influence of a pelvic belt on the abdominal and hip abductor muscles.Objects:To examine the effects of a pelvic belt on the forces of the hip adductor and abductor muscles and activity of the abdominal muscles during isometric hip adduction and abduction.Methods:This study recruited 14 healthy men. All subjects performed isometric hip adduction and abduction with and without a pelvic belt in a neutral hip position. Load cells, wrapped with a non-elastic belt, were placed above the medial and lateral malleoli of the dominant leg to measure the muscle forces of the hip adductors and abductors, respectively. The forces of the hip adductors and abductors were measured using a load cell during isometric hip adduction and abduction, while the electromyographic activities of the bilateral rectus abdominis, internal oblique, and external oblique muscles were measured.Results:The forces generated by the hip adductors and abductors were significantly greater with the pelvic belt than without (p<.05). No significant differences in abdominal muscle activities between the two conditions were found (p>.05).Conclusion:These findings suggest that use of a pelvic belt could lead to effective strengthening exercise of hip muscles in individuals with sacroiliac joint pain.

본 연구는 근육식품의 사후 숙성기간 별 냉동처리가 근육식품의 해동 후 품질 특성에 미치는 효과를 규명하고자 수 행되었다. 근육식품 원료로는 사후 단기간에 강직이 개시되는 전복을 선정하였고, 사후 시간 별 pH 및 전단력 변화를 측정하여 사후강직 개시 시간을 산출하였다. 전복의 냉동은 사후 직후(0 h), 사후강직기(3 h) 및 강직 해지기에 -18°C 및 -50°C 냉동고에서 실시하였고, 24시간 저장 후 유수해동하여 해동감량, pH, 보수력, 전단력 및 색도를 관찰하였다. 본 연구 결과 근육 식품의 품질은 냉동 온도보다는 사후 냉동 시점에 현저하게 영향을 받는 것으로 평가되었는데, 특 히 사후 강직 시기에 냉동처리를 실시한 결과 해동감량 및 보수력 저하가 심각하게 발생하였고, 높은 전단력을 보여 주었다. 반면 사후 직후 급속냉동을 실시하는 경우(-50°C), 해동 후 신선 전복과 유사한 품질을 보여주었다. 따라서 식 육 제품의 경우 사후강직 시기에 냉동하는 경우 품질 열화가 심각하게 발생할 수 있는 반면, 저작성이 필요한 수산 근육 식품의 경우 사후강직기의 해동 처리를 통한 소비자 기호도 향상이 가능할 것으로 평가되었고, 특히 냉장 저장 과정에서 야기되는 조직 연화를 냉동 처리를 통해 효과적으로 제어할 수 있는 가능성을 보여주었다.

식용곤충은 대체 식량자원으로 관심이 증가되고 있다. 본 연구의 목적은 누에나방 번데기 분말 섭취 유무에 따른 저항성운동 훈련(등장성 수축)이 ICR 마우스의 근육량 증가에 미치는 영향을 분석하였다. 이를 위하여 ICR 마우스 28마리를 대조군(CON), 저항성운동 훈련군(EX), 누에나방 번데기 분말 섭취군(SP), 누에나방 번데기분말 섭취 저항성운동 훈련군(SPEX)으로 그룹 당 각각 7마리씩 분류하였다. 체중증가율은 EX와 SPEX가 CON과 SP에 비해 유의하게 억제되었다. 혈중 총 단백질 농도는 SPEX가 다른 그룹에 비하여 가장 높았다. 알부민 농도 변화는 운동훈련 병행 시에만 증가하였다. 혈액 GOT와 GPT 수준은 유의차가 없었다. Akt와 Gsk-3β의 단백질 발현의 유의차는 없었다. 그러나 번데 기 분말 섭취 시 Akt 증가 및 Gsk-3β의 감소 경향이 나타났다. 비복근 근육 양은 저항성 운동 훈련을 하였을 때만 증가하였다. 그리고 또한, 번데 기 분말 섭취 시 근육량은 유의차가 없었으나 증가하는 경향을 보였다. 이러한 결과는 저항성 운동훈련과 누에나방 번데기 분말 섭취는 간독성을 유발하지 않고 근육량을 증가시킬 수 있다는 점을 시사한다. 그러나 보다 상세한 결과를 제시하기 위해 부가적인 연구가 필요할 것이다.

위축돈은 정상돈에 비해 생시체중이 낮고 생후 성장과 발달도 미숙하다. 근육의 성장에 있어 muscle satellite cells(SC)의 역할에 대해 많은 연구가 진행되고 있다. 근육 내에서 줄기세포를 하는 side population(SP) 세포군이 최근 밝혀졌는데, 이 세포군은 Hoechst dye를 이용한 fluorescence-activated cell sorting(FACS)에 의해 이용하여 분리되는데, 다양한 조직(특히 근육)으로 분화되는 것으로 밝혀졌다. 위축돈과 정상돈 근육 내 SC와 SP 세포군의 숫자 및 성상을 비교분석하기 위해 semitendinosus(ST) 근육을 적출하여 SC와 SP를 분리·배양 하였다. 위축돈의 ST는 정상돈에 비해 무게가 가볍고 근섬유의 숫자와 크기도 작았다(p<0.05). 하지만 정상돈과 위축돈의 ST 근육 내 단백질과 DNA 총량은 차이가 없었다. 총 RNA 양과 DNA 농도는 정상돈의 ST 근육에서 위축돈에 비해 높게(p<0.05) 나타났다. ST 근육에서 추출된 총 세포수(yield/g)에는 정상돈과 위축돈 간 차이가 없었다. 세포의 증식률을 0, 24, 48 시간동안 두 그룹 간 차이가 없었다. 세포 배양 72시간 후 정상돈 ST 근육에서 추출된 세포의 증식률이 위축돈의 그것에 비해 높게(p<0.05) 나타났다. 정상돈 ST 근육에서 위축돈 ST 근육에 비해 SP 세포가 더 많이(p<0.05) 추출되었다. 종합해 보면, 위축돈의 근육 크기와 근섬유의 숫자가 정상돈에 비해 작고, 근육내 줄기세포의 역할을 하는 SC와 SP 세포군 또한 낮게 나타난 것은 위축자돈이 임신 기간 동안 충분한 영양을 받지 못하여 근육 내 줄기세포의 증식이 낮아졌으며, 이는 근육 내 줄기세포가 자돈의 성장과 발달에 큰 영향을 미치는 결과로 해석할 수 있다.