• 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.

• PNF and Movement
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• 제8권3호
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• pp.55-61
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• 2010

Purpose : The purpose of this study was to find out which method was efficient to enhance the flexibility of lower back between PNF(proprioceptive neuromuscular facilitation) and hamstring stretching. Method : subject were 20 young people between the ages 20 and 25. subjects were randomly assigned to one of 2groups; PNF(n=10), static(n=10). respective group received the same stretching does of 3days per week for 4weeks. Trunk flexion forward a measuring instrument and tapeline were performed to measurement the flexibility of lower back at different times(before starting the exercise, 4weeks after starting). Results : The results of the study were as follows: The lower back flexibility was increased significantly in PNF groups. PNF, static groups showed meaningful defference in trunk flexion forward. The finding indicate that PNF may be preferred technique for improving flexibility and that flexibility training results in on increased consistency of flexibility scores.

• 대한인간공학회지
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• 제19권2호
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• pp.87-99
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• 2000

This study aims to examine a fuzzy logic-based human expert EMG prediction model (FLHEPM) for predicting electromyographic responses of trunk muscles due to manual lifting based on two task (control) variables. The FLHEPM utilizes two variables as inputs and ten muscle activities as outputs. As the results, the lifting task variables could be represented with the fuzzy membership functions. This provides flexibility to combine different scales of model variables in order to design the EMG prediction system. In model development, it was possible to generate the initial fuzzy rules using the neural network, but not all the rules were appropriate (87% correct ratio). With regard to the model precision, the EMG signals could be predicted with reasonable accuracy that the model shows mean absolute error of 8.43% ranging from 4.97% to 13.16% and mean absolute difference of 6.4% ranging from 2.88% to 11.59%. However, the model prediction accuracy is limited by use of only two task variables which were available for this study (out of five proposed task variables). Ultimately, the neuro-fuzzy approach utilizing all five variables to predict either the EMG activities or the spinal loading due to dynamic lifting tasks should be developed.

• Journal of Korean Neurosurgical Society
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• 제47권5호
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• pp.377-380
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• 2010

The abducens nerve usually travels from the brainstem to the lateral rectus muscle as a single trunk. However, it has been reported that this nerve could split into branches occasionally. We attempted to show the aberrant course of abducens nerve in a specimen with unilateral duplicated abducens nerve and review relevant literatures. The micro-dissections were performed in a head specimen injected with colored latex under the microscope. The abducens nerve was duplicated unilaterally. This nerve emerged from the pontomedullary sulcus as a single trunk and splitted into two branches in the prepontine cistern. These two separate branches were piercing the cerebral dura of the petroclival region respectively. The slender lower branch passed between the petroclinoid and petrosphenoid ligaments and the thick lower one passed under the petrosphenoid ligament. These two branches united just lateral to the ascending segment of internal carotid artery in the cavernous sinus. The fact that there are several types of aberrant abducens nerve is helpful to perform numerous neurosurgical procedures in the petroclival region and cavernous sinus without inadvertent neurovascular injuries.

• Archives of Reconstructive Microsurgery
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• 제20권1호
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• pp.14-17
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• 2011

Autologous breast reconstruction after mastectomy in breast cancer patient is now increasing. The deep inferior epigastric artery (DIEA) free flap is well known as an ideal donor site for the microsurgical breast reconstruction. The branching pattern of the DIEA was well described in the literature. In that study, DIEA has three branching patterns near the arcuate line. We describe a case in which branching variation of the DIEA before entering the posterior surface of the rectus abdominis muscle. In three cases, DIEA originated from the external iliac artery ascended as a double trunk at 1cm, 2cm, and 4cm above the originating point, respectively. In one case, DIEA ascended as a single trunk along the linea alba toward to the umbilicus until it supply overlying subcutaneous tissue. Preoperative 3D computed tomographic angiography to identify the anomaly is recommended and meticulous dissection to the originating point of DIEA is needed.

• 대한물리치료과학회지
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• 제16권3호
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• pp.35-42
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• 2009

Background: The purpose of this study is to measure the amount of influence of taping and a whole body balance upon muscle strength, endurance, and flexibility. Experiments were conducted by two different groups, specially designed for this study. The choice of exercise methods for each group depends on its own idiosyncratic characteristics (or Each group employs its own idiosyncratic exercise method). Methods: The first group, with taping applied, undertook exercises three times a week; second group just took exercises three times a week. These experiments show the following outcomes. Results: The first group showed a considerable amount of difference in terms of muscle strength, endurance, and flexibility. Second group also showed similar outcome. Both the first group and the second group revealed a considerable difference. But the first group showed a bigger difference than the second group. Conclusion: Thus, the result of these experiments strongly indicates that exercise, with taping applied, turns out the most effective in promoting muscle strength, endurance, and flexibility.

• 국제물리치료학회지
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• 제4권2호
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• pp.618-624
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• 2013

The purpose of this study was to test the effect of Gastrocnemius and Low Back-muscle isotonic exercise on static dynamic standing balance during the period of 4 weeks. This study was two groups pretest-posttest design. Nineteen subjects who were over 22 years old were randomly assigned to either the experimental group that received the Gastrocnemius muscle exercise(n=9) or the low back muscle exercise(n=10) : The former group performed isotonic exercise(plantar flexion), the latter group performed isotonic exercise(trunk extension) a total of 18 times for three times per week for four weeks. Two groups also performed static and dynamic balance before the exercise and 4weeks after the exercise. The data were analyzed by using the paired t-test and independent t-test. The results were as follows: As compared with change of dynamic balance performance capacity at two groups, a significant difference was shown in the test(p<.05), but not in static balance(p>.05). Also, a significant difference of balance between groups was not shown in the test. In this study indicated that gastrocnemius and low back muscle isotonic exercise will have positive impact on standing balance.

• The Journal of Korean Physical Therapy
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• 제27권4호
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• pp.258-263
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• 2015

Purpose: This study investigated effects of deep abdominal muscle strengthening exercises on pulmonary function and the ability to balance in stroke patients and was conducted to propose an exercise program for improving cardiovascular function. Methods: Study subjects were 20 patients with hemiplegia due to stroke, who were divided into the deep abdominal muscle strengthening exercise group (experimental group), 10, and the control group, 10. Pulmonary function tests measured FVC and FEV1, dynamic balance ability was measured using TUG. Static and dynamic balance ability was measured using BBS. The experimental group performed exercises during a period of 6 weeks, 5 times a week for 40 minutes, whereas the control group did not participate in regular exercise. The difference before and after the exercise was compared using paired t-test, difference in exercise before and after between groups was ANCOVA and level of significance was set at ${\alpha}=0.05$. Results: The changes in FVC and FEV1 within the group showed a significant difference only in the experimental group (p<0.001) (p<0.01), between-group difference was statistically significant only in FVC and FEV1 changes in the experimental group (p<0.001). The TUG changes within the group showed a significant difference in the experimental group and control group (p<0.001) (p<0.05), while BBS changes showed a significant difference only in the experimental group. Between-group difference was statistically significant only in TUG and BBS changes in the experimental group. The experimental group showed a more effective significant difference than the control group (p<0.001). Conclusion: Can exercise involving a deep abdominal muscle strengthening program be applied in patients with stroke with difficulty in control of trunk and decreased breathing ability?

• 한국운동역학회지
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• 제17권1호
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• pp.111-119
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• 2007

The purpose of this study was to investigate muscle activity and gait pattern in lower limb depending on the outsole of heel rockers. Fifteen healthy men volunteered for this experiment. Each subject performed totally three trails with two pairs of different heel rocker shoes and a pair of normal running shoes at speed of 1.33m/s for 1 minute during walking on a treadmill. Kinematic data gathered in 100Hz was recorded and analyzed by using the 3D motion capture system to measure the trunk tilt and joint angle of the right lower limb. And the lower extremity muscle activities were simultaneously recorded in 1000Hz and assessed by using EMG. The statistical analysis was the one-way ANOVA with the repeated measures to compare among the three kinds of shoes. The level of statistical significance for all tests was 0.05. Joint angle of lower limb was showed statistically significant different in MST(hip joint), LHS(ankle joint), and RTO(knee and ankle joint). Muscle activity of rectus femoris and biceps femoris was statistically increased in both heel rocker shoes during gait cycle on treadmill. The maximum peak time of tibialis anterior in the negative heel rocker showed the delay of approximately 23.8%time than normal shoes. Gait pattern variability of the negative heel rocker was increased in the first half of the stance phase and the variability of the positive heel rocker was increased in the terminal stance phase. In Conclusion, stability was decreased in between joints of lower limb on positive heel rocker than negative heel rocker. This study found that there were different joint angle, muscle activity, gait pattern and coordinate system of the lower limb in each kind of shoes. These unstability affected the lower extremity and the whole body. A further study has to be continued with study of rehabilitation and exercise for a long-term.

• Physical Therapy Rehabilitation Science
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• 제4권1호
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• pp.11-16
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• 2015

Objective: Prone bridge exercise is one of the core strengthening exercise for improving abdominal, lower and upper extremity muscles. In addition, coactivation of the trunk muscles and extremities is important for treatment of low back pain. This study aimed to investigate the correlation between the thickness, cross-sectional area of the target muscle, and endurance during prone bridge exercise. Our hypothesis was that an increase in muscle thickness is positively related to the hold time for the static prone bridge exercise. Design: Cross-sectional study. Methods: Fourteen healthy university students (8 men and 6 women) voluntarily participated in the study at Sahmyook University. Hold time for the prone bridge with one and both legs was measured. The resting and contracted thickness of the lateral abdominal, rectus femoris, and triceps muscles was measured using rehabilitative ultrasound imaging. The correlation between muscle thickness and endurance for maintenance time was evaluated. Results: The prone bridge with both legs and the contraction thickness of the triceps muscle showed a positive correlation (r=0.692, p<0.05); the prone bridge with one leg and the contraction thickness of the internal oblique and transversus abdominis muscles showed a positive correlation (r=0.545, 0.574, p<0.05, 0.05, respectively). Conclusions: Endurance for the prone bridge exercise with a stable support surface is correlated with the contraction thickness of arm muscles; the prone bridge exercise with an unstable support surface is correlated with the contraction thickness of the deep abdominal muscles.