• Journal of The Korean Society of Integrative Medicine
• /
• v.7 no.3
• /
• pp.171-180
• /
• 2019

Purpose : The purpose of this study was to investigate the difference in motor cortical excitability during mental practice and action observation in subjects with forward head posture. Methods : This study was performed in two groups, a forward head posture group (n=17) and a normal posture group (n=17). Electroencephalography (EEG) was conducted to investigate cerebral cortex activity, and six electrodes were attached to Fp1, Fp2, C1, C2, C3, and C4 to measure the relative alpha power, relative beta power, relative gamma power, and mu rhythms. The subjects were requested to perform the four different conditions, which were eye opening, eye closing, mental practice, and action observation for 300 seconds. Results : The results showed that the relative alpha waves showed a significant difference between the normal and forward head posture groups in the C1, C2, C3, and C4 regions with the eyes open (p<.05). The relative beta waves also showed a significant difference between the two groups in the Fp1 and Fp2 regions during action observation (p<.05). The relative gamma waves were significantly different between the normal and forward head posture groups in the Fp1 and Fp2 regions during action observation (p<.05) in C1, C2, and C3 with eyes closed (p<.05) and in C1, C2, C3, and C4 with eyes open (p<.05). Conclusion : The results of this study showed that EEG change in the forward head posture group was different from that in the normal control group in action observation rather than in mental practice. Therefore, we are expected to provide a neurophysiological basis for applying action observation to motor skill learning during exercise for correcting forward head posture.

• The Journal of Korean Physical Therapy
• /
• v.33 no.1
• /
• pp.16-20
• /
• 2021

Purpose: This study examined the effects of the type of video contents used for action observations on the ability to control posture. Methods: The participants were 48 healthy adults. The two hands of the participants were crossed on both shoulders, and the other foot was placed in a straight line in front of the target to allow them to watch a video of the monitor. The videos were presented in random order with three video contents (natural, stable balance posture, and unstable balance posture) consisting of 30 seconds each. A 15-second resting time was given between each video. During action observation using various video content forms, the posture control ability was measured using a TekScan MetScan^® system. Results: The results revealed statistically significant differences in the area of movement and the distance by COP and distance by the type of action-observation videos, and the distance by the anteroposterior and mediolateral sides (p<0.05). The stable balance posture and unstable balance posture video showed significant differences in the distance by the COP, anteroposterior, and mediolateral distance. (p<0.05) Conclusion: This study suggests that choosing the contents of the videos is important during action-observation training, and action-observation training can help improve postural control.

• Journal of the Korea Convergence Society
• /
• v.9 no.12
• /
• pp.123-128
• /
• 2018

The aim of this study was to determine the effects of the action observation and visual feedback on the alignment, pain and function of forward head posture(FHP) and round shoulder(RS). A total of 24 participants with FHP and RSP were randomly assigned to general exercise(GE, n=8), action observation(AO, n=8), and visual feedback(VF, n=8). All subjects were exercised three times a week for four weeks. The groups were assessed for craniovertebral angle(CVA), round shoulder posture(RSP), visual analog scale(VAS), and neck disability index(NDI) before and after exercise, There was a significant difference in CVA in the GE, AO and RSP, VAS and NDI were significantly different in all groups. AO was more effective than GE, VF for VAS. The results of this study suggest that action observation may be effective to improve the FHP and RS.

• Journal of The Korean Society of Integrative Medicine
• /
• v.8 no.1
• /
• pp.113-124
• /
• 2020

Purpose : The purpose of this study was to investigate the effects of exercise intervention combined with 3D visual feedback and motion observation on postural alignment and cerebral cortical activity in subjects with forward head posture (FHP). Methods : The study included 28 participants with FHP, randomly divided into a 3D visual feedback plus motion observation group (n=14) or control group (n=14). The experimental group received corrective exercise combined with 3D visual feedback and motion observation for FHP, three times a week for four weeks. We examined cervical spine radiographs in the lateral standing position with both arms crossed to measure the craniovertebral angle (CVA) and cervical lordosis (CL). Relative alpha (RA) and beta waves (RB) were measured by wireless dry EEG. Results : The CVA value was significantly different between the groups, and the CL value was significantly different only in the experimental group. RA and RB values were not significantly different before and after intervention in the control group. RB values were significantly decreased before and after intervention in the experimental group. Conclusion : Based on the results of this study, we suggest that interventions combined with motion observation and 3D visual feedback may be effective as exercise methods to improve postural alignment and cerebral activity in subjects with FHP. Further research is required to generalize our results on technical supplementation complemented with 3D visual feedback devices.

• Journal of the Korean Society of Physical Medicine
• /
• v.10 no.3
• /
• pp.9-17
• /
• 2015

PURPOSE: This paper aims to present the available angle to evaluate the severity of forward head posture (FHP) with the observation method and photographic method. METHODS: A cross-sectional observation research design study consisted of 29 subjects who was divided two groups (slight FHP group, moderate FHP group) in Eulji university was used. We evaluated the FHP and the angles including CranioVertebral Angle (CVA), Head Tilting Angle (HTA), Head Position Angle (HPA) and Forward Shoulder Angle (FSA) with the Body style S-8.0 (South Korea, LU Commerce). RESULTS: The mean of CVA, FSA from the slight FHP group was shown higher than moderate severe FHP group. According to independent t-test result, but there was no difference among all angles in two groups. The linear discriminate analysis showed the size of distinction of FSA was the biggest, and then CVA, HTA and HPA were in the order. 55.6% of FSA is properly classified in the slight FHP group. CONCLUSION: The FSA is the best to distinguish the severity of FHP and then CVA as the second best. Therefore, FSA is recommended to check the FHP.

• Journal of the Ergonomics Society of Korea
• /
• v.33 no.2
• /
• pp.167-174
• /
• 2014

Objective: This research focuses on the working environment of office workers and aims to propose an ideal seating posture and chair design. Background: Generally, office workers having to seat in a fixed posture for long periods of time tend to suffer from an increased rate of musculoskeletal disorders. Method: The measurement and survey of 123 office workers on their working conditions and literature survey will lead to a suggestion of an ideal seating posture and workstation design theory. Results: Work environment satisfaction appeared low for chair and desks. Work-related pain over the last year was experienced among 47.2% of the respondents in shoulder (34.2%), neck (30.9%). Observation of working posture revealed that only 27.6% of workers utilize backrest during work. Conclusion: Office work embodies many situations where risks of musculoskeletal disorders may be high. Thus, the seated workplace must be set up to allow proper seating posture for workers. Application: The results of this study can be applied as baseline data for preventing musculoskeletal disorders of office workers.

• Journal of the Ergonomics Society of Korea
• /
• v.25 no.2
• /
• pp.51-62
• /
• 2006

In assessing risks related to working posture, pictures of postures are taken from various directions, which can be a source of observation error. Joint postures of the neck, lower back, knee, shoulder, and elbow were taken from 7 different viewing angles and 19 observers estimated joint angles by observing the pictures in 2-dimensional display. The joint angles were also measured using an optoelectronic motion measurement system. The estimation error increased as the viewing angle varies from the right side of the human body, but the patterns differ according to which joint angles were being observed. Guidelines to increase the validity of observation of joint angles were presented based on the results. In general, it is recommended to maintain the viewing angle within 20 degrees from the right side of the human body, while different ranges of viewing angle are recommended for each joint angle.

• Safety and Health at Work
• /
• v.7 no.4
• /
• pp.389-393
• /
• 2016

Job hazard analyses were conducted to assess exposure to musculoskeletal disorder (MSD) risk factors in seven workers of three dry-cleaning establishments. In accordance with the Washington State Ergonomics Rule, the analyses were performed in two separate steps: (1) observation and checklist approaches were made to identify a "caution zone job" in the seven workers' pressing operations across the three shops; and (2) detailed posture and motion analyses were undertaken to determine a "MSD hazard" in one worker's operation using a video technique. One "caution zone job" was identified and it was the pressing operation job in which five physical risk factors were found in the pressing operations. The detailed analyses confirmed that one "MSD hazard", i.e., awkward posture in shoulders, was prevalent in the pressing operations of the three dry-cleaning facilities. It would be desirable to reduce MSD risk factors including awkward shoulder posture in the dry-cleaning industry.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.06a
• /
• pp.277-278
• /
• 2008

• Journal of the Institute of Electronics and Information Engineers
• /
• v.52 no.6
• /
• pp.117-125
• /
• 2015

In the modern age, it is important for people to maintain a good sitting posture because they spend long hours sitting. Posture correction treatment requires a great deal of time and expenses with continuous observation by a specialist. Therefore, there is a need for a system with which users can judge and correct their postures on their own. In this study, we collected users' postures and judged whether they are normal or abnormal. To obtain a user's posture, we propose a four-joint motion capture system that uses inertial sensors. The system collects the subject's postures, and features are extracted from the collected data to build a database. The data in the DB are classified into normal and abnormal postures after posture learning using the K-means clustering algorithm. An experiment was performed to classify the posture from the joints' rotation angles and positions; the normal posture judgment reached a success rate of 99.79%. This result suggests that the features of the four joints can be used to judge and help correct a user's posture through application to a spinal disease prevention system in the future.