• Journal of the Ergonomics Society of Korea
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• v.28 no.3
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• pp.41-47
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• 2009

The purpose of this study, during the lifting task was researching the difference and a relationship between the ground reaction force and the grip strength by change of position. After grip strength has measured in symmetry position and asymmetry position at 45cm and 75cm of height of hand, ground reaction force was measured by same attitude lifting wooden box. We analyzed the difference of grip strength and ground reaction force in each position change. The results of grip strength, the grip strength of both hand were significant difference that in study subject symmetry and asymmetry position (p<0.01). The results of symmetry lifting task, the study subjects was significant difference of the ground reaction force difference by height (p<0.05). Asymmetry lifting task was significant difference of ground reaction force difference by direction of rotation was changed (p<0.01). The result of it will rotate with non-dominant hand side of lifting tasks from height 75cm where it easily maintains a balance possibility and decreasing the load of the hand. Therefore, from the workshop in the work people, it will be between the height 75cm and non-dominant hand side of trunk rotatory direction in the lifting tasks. Future study is necessary researched about the change of grip strength when the height of the hand is higher, and the difference of the ground reaction force when the change of weight.

• Physical Therapy Rehabilitation Science
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• v.6 no.1
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• pp.1-6
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• 2017

Objective: There are many types of exercises with upper and lower-limb action for activation of abdominal muscles for trunk stabilization. A comparison of the different exercise methods been very useful to enhance the result from the exercise for treatment. The purpose of this study was to investigate through surface electromyography (EMG) the changes in abdominal muscle activity during the performance of three different dead-bug exercise methods performed at three different speeds. Design: Cross-sectional study. Methods: The subjects were 30 healthy adults (13 males and 17 females). We instructed the subjects to perform three different dead-bug exercises. We also applied three different speeds to the dead-bug exercises; 60 bpm, 90 bpm, and 120 bpm with use of a metronome. The assessment of EMG was percentage of maximal voluntary isometric contraction on the rectus abdominis (RA), external oblique (EO), and internal oblique (IO). Results: EMG activation of the RA, EO and IO muscles was significantly greater at the higher speed (p<0.05). There was a significant increase in abdominal muscle activity during the dead-bug exercise performed with both the upper and lower extremities compared to that with only the upper extremity or the lower extremities (p<0.05). Conclusions: These findings demonstrate that the performance of the dead-bug exercise with both the upper and lower extremities combined at a high speed is more effective compared to other exercises. Therefore, it is suggested that more favourable and effective outcomes may occur when the type and speed of the exercise is chosen appropriately.

• Physical Therapy Rehabilitation Science
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• v.10 no.2
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• pp.167-174
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• 2021

Objective: Single leg bridge exercise (SLBE) improves trunk muscle activation and provides muscle stability by aligning joints related to posture. This preliminary study aimed to investigate the effects of SLBE on abdominal muscle activation in subacute stroke patients. Design: Cross-sectional study. Methods: Fifteen subacute stroke patients (9 males, 6 females) voluntarily participated in this study. SLBE was performed on the affected side. Each individual patient performed an SLBE ten times in three sets and was asked to hold their position for 5 s. Muscles activity was recorded using a surface electromyography (EMG) system before and after the SLBE. A surface EMG system was used to analyze the muscle activity during general bridge exercise, including the rectus abdominis (RA), internal oblique (IO), and external oblique (EO) abdominal muscles. Results: Muscle activity of both EO and IO on the affected side significantly increased (p<0.05), whereas the muscle activity of the RA and the three muscles on the unaffected side did not show a significant difference. In addition, improvement in muscle asymmetry of the EO and IO showed a significant change after SLBE (p<0.05). Conclusions: SLBE is effective in activating the abdominal muscles of stroke patients on the affected side and is a helpful exercise intervention that activates the muscles to transform asymmetric abdominal muscles into symmetric patterns.

• International journal of advanced smart convergence
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• v.9 no.4
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• pp.26-33
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• 2020

This study measured the downward stepping movement relative to weight change (no load, and 10%, 20%, 30% of body weight respectively of adult male (n=10) from standardized stair (rise of 0.3 m, tread of 0.29 m, width of 1 m). The 3-dimensional cinematography and ground reaction force were also utilized for analysis of leg stiffness: Peak vertical force, change in stance phase leg length, Torque of whole body, kinematic variables. The strategy heightened the leg stiffness and standardized vertical ground reaction force relative to the added weights (p<.01). Torque showed rather larger rotational force in case of no load, but less in 10% of body weight (p<.05). Similarly angle of hip joint showed most extended in no-load, but most flexed in 10% of body weight (p<.05). Inclined angle of body trunk showed largest range in posterior direction in no-load, but in vertical line nearly relative to added weights (p<.001). Thus the result of the study proved that downward stepping strategy altered from height of 30 cm, regardless of added weight, did not affect velocity and length of lower leg. But added weight contributed to more vertical impulse force and increase of rigidity of whole body than forward rotational torque under condition of altered stepping strategy. In future study, the experimental on effect of weight change and alteration of downward stepping strategy using ankle joint may provide helpful information for development of enhanced program of prevention and rehabilitation on motor performance and injury.

• Physical Therapy Rehabilitation Science
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• v.10 no.2
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• pp.205-211
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• 2021

Objective: This study aimed to identify the effects of assuming different knee angles and hip abduction during bridge exercise and hip thrust exercise on lower body muscle activity. Design: Cross-sectional study Methods: Thirty-three healthy adults (18 men and 15 women) were instructed to perform the bridge and hip thrust exercises while randomly assuming 120°, 90° and 60° of knee flexion and 0° and 30° of hip abduction. EMG data (%maximum voluntary isometric contraction) were recorded three times from the erector spinae (ES), gluteus maximus (GM) and biceps femoris (BF) muscles of participant's dominant side and the mean values were analyzed. Results: The results showed that, during the hip thrust compared to the bridge exercise, there was significantly greater gluteus maximus muscle activity in all hip conditions while the biceps femoris activity was significantly less, and the erector spinae muscle activity was significantly greater with 30° of hip abduction (p<0.05). With all exercises, the erector spinae and the biceps femoris exhibited significantly greater muscle activity with 60° of knee flexion compared to 90° and 120° of knee flexion (p<0.05), and significantly greater muscle activity with 90° compared to 120° of knee flexion (p<0.05). In the case of the gluteus maximus, greater muscle activity was exhibited with 120° compared to 60° of knee flexion with all hip abduction conditions (p<0.05). Conclusions: It was effective for muscle activation of main agonists such as the gluteus maximus and erector spinae during thrust exercise, and the change in knee flexion angle was effective for muscle activation of the gluteus maximus. Therefore, it is considered that this study can be used as a selective indicator of the target movement angle during hip strengthening exercise for specific muscles.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.4
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• pp.1-17
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• 2023

PURPOSE: The purpose of this study was to compare how the shoulder height and respiratory function are affected by applying shoulder stabilization exercises and core stabilization exercises that are effective for strengthening the trunk muscles and postural stability for adults with a round shoulder posture (RSP). METHODS: The participants were 28 young adults with RSP. They were assigned randomly to two groups: shoulder stabilization exercise and core stabilization exercise. They performed the exercises for 30 minutes twice a week for four weeks. They measured the shoulder height and respiratory function before and after exercise. RESULTS: No significant difference in shoulder height was found between the groups. A significant decrease in shoulder height was found in the shoulder stabilization exercise group after exercise. The core stabilization exercise group showed a significant decrease after exercise. In respiratory function, no significant difference was found between the groups. The forced vital capacity (FVC) and forced expiratory volume in one second (FEV₁) were increased significantly in the shoulder stabilization exercise group before and after exercise. The FEV₁, FEV₁/FVC, and peak expiratory flow were significantly higher in the shoulder stabilization exercise group after exercise than in the core stabilization exercise group. CONCLUSION: Shoulder stabilization exercise and core stabilization exercise improved the postural alignment and pulmonary function, and the exercises could be helpful in shoulder rehabilitation as well as the clinical part of the treatment of rounded shoulder posture.

• The Journal of Korean society of community based occupational therapy
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• v.4 no.1
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• pp.75-84
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• 2014

Objective : This study intends to suggest an effective clinical intervention method for stroke patients by applying a trunk stabilization training program to a single stroke patient and investigating and analyzing the effects of the program on postural control and activities of daily living. Methods : The subject of this study was a 75 year-old female stroke patient hospitalized in C Hospital located in Gyeongju, Gyeongsangbuk-do. As for the research design, A-B-A reversal design was used with a single subject design; and the research period was a total of five weeks from April 21, 2014 to May 23, 2014. As for the research process, a total of 15 sessions were carried out including three sessions of baseline(A), nine sessions of an intervention period(B), and three sessions of maintenance(A'); and the trunk stabilization program was applied during the intervention period. To evaluate the participant's postural control and activities of living life, the Postural Assessment Scale for Stroke(PASS) and the modified Barthel Index(MBI) were used. Visual analysis was used in which collected data were plotted on a graph, using Microsoft Office Excel 2013. Results : In the postural control test, the mean scores improved from 11.7 in the baseline phase to 14.8 in the intervention phase and 15.3 in the maintenance phase. In the evaluation of activities of daily living, the score improved from 66(medium dependence) during the baseline period to 80(low dependence) after intervention and at the maintenance phase. Conclusion : It was found that the trunk stabilization training program showed effects on the stroke patient's postural control or alignment, and furthermore a beneficial improvement in the patient's performing the activities of daily living, as well.

• Journal of Korean Physical Therapy Science
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• v.6 no.3
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• pp.25-40
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• 1999

The hub of weight bearing in the human body for both static and dynamic activities is the lumbopelvic region. It is a key region of extraordinary stability, since the trunk and ground forces converage in this region. The two sacroiliac joints form an integral part of this lumbopelvic unit. Considerable effort has been expended to study and quantify the normal range of movement of the sacroiliac joints Mitchell suggests that the ilium rotates in a posterior direction at heel strike and progresses in an anterior direction as the individual passes through the stance phase. The overall key appears to lie in determining the weight-bearing pattern of the sacroiliac (lumbopelvic) region from above and below that results in the familiar pain of sacroiliac dysfunction, assessing the status of the injured tissues, and intervening with the proper treatment protocols that maximize the body's healing processes. The purpose of this chapter is to provide a comprehensive overview of the sacroiliac joint's tissues and biomechanics, as well as concepts of evaluation and treatment. This overview is aimed at assisting the clinician in identifying the forces that are potentially destructive to the lumbopelvic tissues.

• Journal of Electrical Engineering and Technology
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• v.10 no.6
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• pp.2413-2419
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• 2015

Core spinal muscles are related to trunk stability and assume the main role of stabilizing the spine during daily activities; strengthening of core muscles around the spine can therefore reduce the chance of back pain. The objective of the study was to investigate the effect of core muscle strengthening in the spine during spine stabilization exercise using a whole body tilt device. To achieve this, a validated musculoskeletal (MS) model of the whole body was used to replicate the input motion from the whole body tilting exercise. An inverse dynamics analysis was executed to estimate spine loads and muscle forces depending on the tilting angles of the exercise device. The activation of long and superficial back muscles such as the erector spinae (iliocostalis and longissimus) were mainly affected by the forward direction (-40°) of the tilt, while the front muscles (psoas major, quadratus lumborum, and external and internal obliques) were mainly affected by the backward tilting direction (40°). Deep muscles such as the multifidi and short muscles were activated in most directions of the rotation and tilt. The backward directions of the tilt using this device could be carefully applied for the elderly and for rehabilitation patients who are expected to have less muscle strength. In this study, it was shown that the spine stabilization exercise device can provide considerable muscle exercise effect.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.415-425
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• 2000

It is well known that the lifetime incidence of low back pain is extraordinarily high, but those who incur the majority of the cost, both personally and financially, are the chronic pain. Stabilization programmers attracted our interest, with their aims of using the muscle system to protect spinal joint structures from further repetitive microtrauma, recurrent pain and degerative change. In overviewing the stabilizing role of the trunk and back mucles our attention became focused on muscles which controlled the lumbar and lumbosacral joints rather than on muscles which span the spine from the thorax to pelvis. It was considered that muscles such as the lumbar multifidus, transversus abdominis, and possibly also parts of the obliquus internus abdominis, would most likely function to stabilize the segments of the lumbar spine. In order to check if these muscles were functioning in low back pain patients, it was necessary to devise specific muscle tests. The new concept involves exercises using only relatively low activity levels in the muscles. More emphasis is placed on a motor skill which has to be relearned, practised and then gradully incorporated back into functional movement.