• Journal of the Korean Society of Physical Medicine
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• v.18 no.2
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• pp.13-21
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• 2023

PURPOSE: This study examined the specific clinical risk factors in middle-aged men with age-related loss of skeletal muscle mass (ALSMM). METHODS: The present research analyzed the data from a cross-sectional study of 1,564 community-dwelling participants aged between 40 to 49 years old. The participants were screened for ALSMM. The study examined various risk factors, including age, height, weight, body mass index, waist circumference, skeletal muscle mass index, smoking and drinking status, systolic and diastolic blood pressure, fasting glucose levels, and triglyceride and cholesterol levels. RESULTS: The risk factors of ALSMM were height, body mass index, waist circumference, skeletal muscle mass index, systolic blood pressure, diastolic blood pressure, drinking status, fasting glucose, and triglyceride levels (p < .05). The weight, triglyceride, and smoking status variables were non-significant (p > .05). CONCLUSION: The risk factors for ALSMM among community-dwelling adults were determined. These results are expected to contribute to the existing literature on ALSMM and provide potential risk factors associated with the development of ALSMM in middle-aged males.

• Journal of Digital Convergence
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• v.13 no.10
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• pp.533-539
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• 2015

The purpose of this study was to investigate the effects of 12weeks complexed lower body muscle-strengthening exercise program on fall risk in elderly women. Twenty subjects volunteered to participate who use a welfare center in W city For the study we divided into two groups: exercise group (EC, n=10, mean age:$69.6{\pm}2.2$), comparative group(CG, n=10, mean age:$71.3{\pm}4.6$). In order to investigate the effect of lower body muscle-strengthening program on the degree of risk of fall. It reached a conclusion as follows after having applied BBS (Berg Balance Scale) and OLST (One-Leg Stance Test) to examine the degree of risk of fall. As a result of changes in BBS and OLST, there were significant differences between EG and CG for each test(p<.00). Therefore, it confirmed that the application of complexed lower body muscle-strengthening program to the elderly who have a high risk of fall influences the risk of fall positively.

• Journal of Digital Convergence
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• v.12 no.10
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• pp.597-604
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• 2014

This research aimed at comparative analysis of body composition and basic physical strength of model majored female college students and general female college students. The research object was composed of 15 model majored female college students of D University, who learned the purpose of this research enough and wrote the consent form of voluntary participation and 15 general female college students, who have no medical history and currently no special disease, and no experience in regular exercise. They underwent body composition inspection, left right grasping power which is the basic physical strength, back muscle strength, flexibility, rapidity, muscle endurance, and the researcher performed descriptive statistics to calculate the average standard deviation, and analyzed to verify difference between groups by using independent t-test. With statistical significance level p<.05, the results are as follows. model majored female college students and general female college students showed meaningful difference between groups in weight, skeletal muscles, body fat volume, BMI and left right grasping power, back muscle strength, rapidity(p<.05). between groups in flexibility and muscle endurance(p>.05).

• Safety and Health at Work
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• v.7 no.1
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• pp.49-54
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• 2016

Background: Prolonged sitting leads to low back discomfort and lumbopelvic muscle fatigue. This study examined the characteristics of body perceived discomfort and trunk muscle fatigue during 1 hour of sitting in three postures in office workers. Methods: Thirty workers sat for 1 hour in one of three sitting postures (i.e., upright, slumped, and forward leaning postures). Body discomfort was assessed using the Body Perceived Discomfort scale at the beginning and after 1 hour of sitting. Electromyographic (EMG) signals were recorded from superficial lumbar multifidus, iliocostalis lumborum pars thoracis, internal oblique (IO)/transversus abdominis (TrA), and rectus abdominis muscles during 1 hour of sitting. The median frequency (MDF) of the EMG power spectrum was calculated. Results: Regardless of the sitting posture, the Body Perceived Discomfort scores in the neck, shoulder, upper back, low back, and buttock significantly increased after 1 hour of sitting compared with baseline values ($t_{(9)}=-11.97$ to -2.69, p < 0.05). The MDF value of the EMG signal of rectus abdominis, iliocostalis lumborum pars thoracis, and multifidus muscles was unchanged over time in all three sitting postures. Only the right and left IO/TrA in the slumped sitting posture was significantly associated with decreased MDF over time (p = 0.019 to 0.041). Conclusion: Prolonged sitting led to increased body discomfort in the neck, shoulder, upper back, low back, and buttock. No sign of trunk muscle fatigue was detected over 1 hour of sitting in the upright and forward leaning postures. Prolonged slumped sitting may relate to IO/TrA muscle fatigue, which may compromise the stability of the spine, making it susceptible to injury.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.640-647
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• 2008

Breed differences in adult animals are determined during fetal development. If interventions are to be developed that influence growth of muscle and fat, it is important to know at which time during gestation breed differences appear and are fixed. The objective of this study was to characterize fetal development in cattle of different breeds. Pregnant cows of 4 cattle breeds with different growth impetus and muscularity were slaughtered under normal processing conditions and the fetuses were removed. German Angus, a typical beef cattle; Galloway, a smaller, environmentally resistant beef type; Holstein Friesian, a dairy type; and Belgian Blue, an extreme type for muscle growth were used. Fetuses of each breed were investigated at 3, 6, and 9 mo of gestation. Fetuses were weighed and dissected into carcass, organs, and muscles. Body fat weight was obtained using the Soxhlet extraction method. Fetal weight increased most rapidly in the third trimester of gestation mainly due to the accelerated muscle and fat deposition. The organ weight to body weight (BW) ratios decreased and the muscle and fat weight to BW ratios increased. At 3 mo of gestation, Galloway fetuses had the significantly smallest BW, half-carcass weight, leg weight, organ weight, muscle weight and shortest leg length. In contrast, Holstein fetuses had the significantly greatest BW, liver, kidney, and lung weights and significantly longest leg length among the 4 breeds, but no differences between Holstein Friesian and Belgian Blue were detected in half-carcass and leg weight. Indeed, Belgian Blue fetuses had the significantly greatest half-carcass weight, leg weight, and muscle weight at 9 mo of gestation, and Galloway had a significantly greater body fat to BW ratio than Holstein Friesian and Belgian Blue. These differences were not evident at 3 and 6 mo of gestation. These data show that the profound increase of tissue and organ weights occurred in later gestation in cattle fetuses even though breed differences were evident as early as 3 mo of gestation. Depending on the tissue of interest, impacting fetal growth likely needs to occur early in gestation before the appearance of breed-specific differences.

• Biomedical Science Letters
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• v.15 no.4
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• pp.301-307
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• 2009

Whole-body insulin resistance results largely from impaired insulin-stimulated glucose disposal in skeletal muscle. Our previous studies using differential display and quantitative real-time RT-PCR have shown that a novel cDNA band (DD23) had a higher level of expression in insulin resistant skeletal muscle and it was correlated with whole-body insulin action, independent of age, sex, and percent body fat. In this study, we cloned and characterized DD23. The DD23 sequence is part of the 3'UTR region of the RNA binding motif, single stranded interacting protein (RBMS3). We have cloned the full length cDNA for RBMS3 and identified two splice variants. These variants named DD23-L and DD23-S have 15 and 14 exons respectively and differ from RBMS3 in the 3'UTR significantly. Northern blot analyses showed that an ~8.8 kb mRNA transcript of DD23 was predominantly expressed in skeletal muscle and to a lesser extent in placenta, but not in heart, brain, lung, liver, or kidney, unlike RBMS3. Elevated expression levels of these novel alternatively spliced variants of RBMS3 in skeletal muscle may play a role in whole body insulin resistance.

• PNF and Movement
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• v.15 no.2
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• pp.185-194
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• 2017

Purpose: The purpose of this study was to prove the effects of the PNF patterns combined with whole-body vibration (PWBV) training on muscle strength, balance, walking speed, and endurance in stroke patients. Methods: Sixteen subjects were randomly assigned to the PWBV group (n=8) and the whole-body vibration (WBV) group (n=8). The PWBV group performed PNF pattern exercises using sprinter combined with WBV, while the WBV group performed using squatting for 30 minutes. Both groups performed therapeutic interventions five days per week over a period of four weeks. The manual muscle test, timed up and go test (TUG), 10-meter walk test (10MWT), and six-minute walk test (6MWT) were used to assess the muscle strength, balance, and gait of the participants. The SPSS Ver. 19.0 statistical program was used for data processing. Statistical analysis included a pared t-test to compare the pre- and post-intervention, and an independent t-test was used to compare groups. The significance level was set as 0.05. Results: The PWBV group and WBV group showed significant improvements in the TUG, 10MWT, and 6MWT (P<0.05). Significant differences between the PWBV and WBV groups were found (P<0.05). Conclusion: The PWBV improved muscle strength, balance, gait speed, and endurance in stroke patients. Thus, PWBV may be suggested as a therapeutic intervention in patients with stroke hemiplegia.

• 한국체육학회지인문사회과학편
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• v.56 no.4
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• pp.575-584
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• 2017

The purpose of this study was to examine the effects of low intensity resistance training speed on body composition, muscle activity and muscle strength in obese middle-aged women. The subjects (n = 12) were randomly assigned to normal resistance training speed group (NSG, n = 6) and slow resistance training speed group (SSG, n = 6). NSG was performed the for 3 sets ${\times}$ 35 times and total 3-s per repetition (eccentric: 1-s, isometric: 1-s, concentric: 1-s), and SSG performed for 3 sets ${\times}$ 15 times and total 7-s per repetition (eccentric: 3-s, isometric: 1-s, concentric: 3-s). Both groups performed the low intensity resistance training at 30% of 1-RM for 105-s per set, rest for 1 min between sets, rest for 3 min between exercises, and 2~3 times per week, for 4 weeks. The body composition, muscle activity and muscle strength were measured before and 4 week after resistance training. WHR at NSG and body fat at SSG were significantly decreased after resistance training compared with before (P<.05). Ｍuscle activity of biceps brachii, vastus medialis and vastus lateralis at both groups were significantly decreased after resistance training compared with before (P<.05, P<.01). Muscle strength of biceps curl and leg extension at both groups were significantly increased after resistance training compared with before (P<.01). However, body composition, muscle activity and muscle strength did not show statistically significant differences between the groups. Our results suggest that body composition, muscle activity and muscle strength should closely related to the performance time of resistance training (development time of muscle contraction), rather than resistance training speed (repetition frequency).

• The Journal of Korean Physical Therapy
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• v.31 no.2
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• pp.129-133
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• 2019

Purpose: This study aimed to investigate effect of ankle instability on peripheral muscle activation among female ballet dancers to provide information on the development of prevention programs for ankle injury rehabilitation. Methods: 32 female ballet dancers were randomly divided into two groups: experience ankle sprain group (n=16, age, $20.7{\pm}0.8years$, BMI $18.6{\pm}1.2kg/m2$) and non-experience ankle sprain group (n=16, $age=21.0{\pm}0.8years$, BMI $19.6{\pm}2.0kg/m2$). Activation of the peroneus longus, tibialis anterior muscle, and gastrocnemius during vertical landing, half pointe, and gait between the two groups were measured. Body composition analyzer was used to examine skeletal muscle mass and body fat mass. Results: A total of 32 patients were included. In the experience ankle sprain group (n=16: left sprain 14, right sprain 2), average ankle sprain injury occurred 7.5 months before the study. The average age of the dancers in the experience ankle sprain group and non-experience ankle sprain group was $20.7{\pm}0.8$ and $21.0{\pm}0.8years$, major period was $64.5{\pm}23.8$ and $71.6{\pm}25.8months$, BMI was $18.6{\pm}1.2$ and $19.5{\pm}2.0kg/m2$, respectively. No significant differences were found on body composition between the two groups (p>0.05). The experience ankle sprain group showed significantly lower tibialis anterior and peroneus longus muscle activation (p<0.5), while gastrocnemius muscle activation appeared to be significantly higher (p<0.05) during landing, half pointe, and normal gait. Conclusion: Ankle sprain can cause a decline in peripheral muscle activation and coordination, which increased the risk for repetitive ankle sprain in the future. Moreover, ankle peripheral muscle selective strength training, coordination program development, and application need to be considered to prevent ankle sprain.

• Korean Journal of Applied Biomechanics
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• v.33 no.3
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• pp.101-109
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• 2023

Objective: The aim of this study is to verify the differences in muscle characteristics of elite level swimmers before and after a 2-hour practice session. Method: The study was conducted on 15 elite swimmers. Preliminary measurements for each muscle (Anterior Deltoid, Triceps Brachii, Biceps Brachii, Flexor Carpi Ulnaris) were taken using the MyotonPRO device before training. After approximately 2 hours of training, the same muscle areas were measured again. The collected data was analyzed through descriptive statistics and two-way 2×2 RG·RM ANOVA, and all statistical significance levels were set at α=.05. Results: After analyzing the characteristics of the Flexor Carpi Ulnaris (FCU) before and after training in both proficiency level swimmers (excellent, non-excellent), it was found that the interaction effect of group X repetition in muscle tension (F), muscle stiffness (S), and body recovery time (R) was statistically significant. Secondly, in the analysis of the Biceps Brachii (BB), the main effect of repetition in muscle tension (F), muscle stiffness (S), and body recovery time (R) was statistically significant. Furthermore, the interaction effect of group X repetition in muscle stiffness (S) and body recovery time (R) was statistically significant. Conclusion: The efficient use of FCU and BB suggests that it is an important factor distinguishing the performance of excellent and non-excellent swimmers in swimming. Therefore, if we develop and apply measures to efficiently utilize FCU and BB during training, it can help improve the performance of the athletes.