• Physical Therapy Korea
• /
• v.9 no.2
• /
• pp.43-50
• /
• 2002

This study was designed to identify the effects of walking conditions (normal walking vs. toe-walking) on electromyographic (EMG) activity of gastrocnemius, tibialis anterior, and soleus muscle. Seven healthy adult males participated in this study. The exclusion criteria were orthopedic or neurologic disease, congenital anomaly or acquired deformity, or pain in low back or lower extremities. The maximal voluntary isometric contraction for each muscle was used for the reference contraction, and EMG activity of each muscle during normal walking and toe-walking was expressed as a percentage of reference contraction. The gait cycle was determined with two foot switches, and gait was normalized as 100% gait cycle for each condition. The maximal values of EMG activity in terminal stance (30~50% of gait cycle) of each condition were compared for data analysis. No significant differences were found in EMG activity of the tibialis anterior and soleus (p>.05), whereas significant decrement was found in EMG activity of gastrocnemius during toe-walking compared to normal walking (p<.05). There is a limitation to generalize the results of this study, because small number of subjects participated for this study and only EMG was used for data collection. The treatment methods should be developed to improve gait efficiency by substituting the weakened muscles secondary to upper motor neuron, or by strengthening the distal muscles in lower extremity.

• Journal of the Korea Safety Management & Science
• /
• v.4 no.2
• /
• pp.11-22
• /
• 2002

In this study, an asymmetric lifting posture prediction model was developed, which was a three-dimensional model with 12 links and 23 degrees of freedom open kinematic chains. Although previous researchers have proposed biomechanical, psychophysical, or physiological measures as cost functions, for solving redundancy, they lack in accuracy in predicting actual lifting postures and most of them are confined to the two-dimensional model. To develop an asymmetric lifting posture prediction model, we used the resolved motion method for accurately simulating the lifting motion in a reasonable time. Furthermore, in solving the redundant problem of the human posture prediction, a moment weighted Joint Range Availability (JRA) was used as a cost function in order to consider dynamic lifting. However, it is known that the moment weighted JRA as a cost function predicted the lower extremity and L5/S1 joint motions better than the upper extremities, while the constant weighted JRA as a cost function predicted the latter better than the former. To compensate for this, we proposed a hybrid moment weighted JRA as a new cost function with moment weighted for only the lower extremity. In order to validate the proposed cost function, the predicted and real lifting postures for various lifting conditions were compared by using the root mean square(RMS) error. This hybrid JRA reduced RMS more than the previous cost functions. Therefore, it is concluded that the cost function of a hybrid moment weighted JRA can be used to predict three-dimensional lifting postures. To compare with the predicted trajectories and the real lifting movements, graphical validations were performed. The results also showed that the hybrid moment weighted cost function model was found to have generated the postures more similar to the real movements.

• Physical Therapy Korea
• /
• v.14 no.3
• /
• pp.64-71
• /
• 2007

The purposes of this study were to determine correlations between the Berg Balance Test (BBS), Timed -UP & Go Test, Fugl Meyer-L/E, Balance, Sensory (FM-L/E, B, S), Motor Assessment Scale-Gait (MAS-G), Comfortable maximal Gait Speed (C MGS), and the Modified Barthel Index (MBI). The subjects were 40 stroke patients of the Korea National Rehabilitation Center in Seoul. Main outcome measures were Balance control (BBS, FM-B), Gait (TUG, C MGS, MAS-G), ADL (MBI) and Motor Function of Lower Extremities (FM-L/E, S). The data were analyzed using Pearson product correlation. FM scales between other clinical and instrumental indexes and multiple stepwise regression analyses were performed to identify prognostic factors for Balance, Gait and ADL Motor Function of Lower Extremity inclinations. The results of this study were as follows: The BBS, FM-L/E, balance, sensory and MBI showed positive correlation relations, but TUG and C MGS showed negative correlations. The sensory factor of the FM-scale showed the strongest variance in predicting BBS. However the FM-balance showed the strongest variance in predicting TUG, MAS-G and C MGS. The use of both quantitative and qualitative scales was shown to be a good measuring instrument for the classification of the general clinical performance of the patients.

• Journal of the Korean Society of Safety
• /
• v.26 no.5
• /
• pp.81-88
• /
• 2011

The goal of this study was to determine whether food industry workers are exposed to musculoskeletal loads due to the work time, frequency, awkward postures and inappropriate workspace design. Three catering workers were evaluated based on job analysis and posture analysis. The results showed that the four most time-consuming tasks were arranging(17%), cooking(16%), handling before cooking(15%) and cutting(15%), and the four most frequent tasks were arranging(21%), cooking(18%), handling after cooking(16%) and handling before cooking(13%). The most common posture was a standing posture(73%) with neutral back(73%), and bent head(50%), left lower arm(71%), right lower arm(78%) and right hand(60%). The comparative analysis of subtasks for the risk levels of musculoskeletal disorders was conducted using the work time, frequency and cumulative time of the postures. The 'displaying' and 'handling after cooking' showed higher risk levels than other subtasks. In addition, the height and length of the tables were evaluated to be inadequate for the workers. It can be concluded that the working environments for catering workers of restaurants should be improved due to the high cumulative time of awkward postures of upper extremities.

• Korean Journal of Applied Biomechanics
• /
• v.23 no.2
• /
• pp.159-167
• /
• 2013

The purpose of this study was to evaluate the gender differences on gait pattern and the kinetics on lower extremities according to the different gait speed. Ten collegiate male students (age : $23.80{\pm}2.94$ yrs, height : $179.40{\pm}5.04$ cm, weight : $66.57{\pm}5.64$ kg) and ten female students (age : $23.40{\pm}2.91$ yrs, height : $166.06{\pm}5.61$ cm, weight : $53.76{\pm}2.75$ kg) participated in this study. To investigate the role, the ratio of the use, and the effectiveness of each joint during gait, we examined the joint work and the contribution to total work. The results of this study were as follows: First, gait pattern was not differ between male and female, hip joint ROM increased with the increase of gait speed both male and female. Second, the eccentric work of the ankle joint decreased with the increase of the gait speed both male and female, on the other hand increased on the knee joint. Third, in the result of the contribution to total eccentric work, male in both the two gait speed was the biggest on the hips joint. However, female in normal gait speed was the greatest on the ankle joint, was the most on the knee joint in the fast gait speed. Forth, the concentric work on the ankle and hip joint increased with the increase of gait speed both male and female. Fifth, in the result of the contribution to total concentric work, there is no difference in the male both the two gait speed, however decreased in the female on the knee joint with the increase of the gait speed, on the other hand increased on the ankle joint.

• PNF and Movement
• /
• v.13 no.2
• /
• pp.89-93
• /
• 2015

Purpose: This study aimed to verify the effect of integrated patterns (IPs) of PNF on individuals with malalignment using upper extremity and lower extremity patterns simultaneously. This information was then compared to the effect of bowling exercises on malalignment. The study population included individuals in their twenties with malalignment in their posture. Methods: Individuals with malalignment (40 participants in total) were divided into 2 groups based on trunk inclination and side deviation. In one group, IPs of PNF were used as interventions, while the other group used bowling exercises. This process was completed over the course of four weeks. The IP group used two patterns simultaneously: flexion-adduction-external rotation and extension-abduction-internal rotation. These patterns were used in the upper and lower extremities and were crossed diagonally. Results: The trunk inclination decreased in the IP and the bowling group. In the IP group, the degree of inclination decreased from 0.94 to 0.33. The side deviation also decreased to 1.53 (p < 0.05). In the bowling group, the two measured values decreased significantly (p < 0.05). Conclusion: Compared to the bowling exercises used in the bowling group, the results of this study indicate that the use of IPs had a significant effect on trunk inclination and side deviation for malalignment posture patients. Individuals can easily improve malalignment using IPs of PNF (for example, at home or at their office), which suggests that they are not required to seek assistance from a fitness or bowling center, which may save them time.

• The Journal of Korean Physical Therapy
• /
• v.30 no.6
• /
• pp.234-238
• /
• 2018

Purpose: Aim of this study was to investigate whether there are ipsilateral motor deficits for visuospatial accuracy and fine movements by making a comparison between stroke patients and healthy subjects. We examined whether ipsilateral motor deficits are influenced by the level of functional movements and muscle strength of the upper and lower extremities of the affected side. Methods: Thirty post-stroke subjects and 20 normal aged matched subjects were recruited. Outcome measures for less-affected side were the tracking task and nine-hole pegboard test. Fugl-Meyer test and motricity index were applied for the measurement of functional movements and muscle strength of affected side. Results: Tracking task and nine-hole pegboard test was significantly different between control and experimental group. In terms of accuracy index according to tracking, the experimental group showed a lower accuracy index in the MCP joint than the control group. However, there were no significant difference relation between the level of motor function of the affected side and the motor deficit level of ipsilateral side. Conclusion: Ipsilateral motor deficits may have significant clinical implications. It needs to be noted that although many patients, families, and medical staff are focused only on motor deficits of the affected side, motor deficits of the sound side can cause difficulties in daily living movements requiring delicate movements. In addition, there was no significant correlation between the level of motor function of the affected side and motor deficits of the sound side.

• Physical Therapy Rehabilitation Science
• /
• v.7 no.4
• /
• pp.154-163
• /
• 2018

Objective: The purpose of this study was to investigate the effects of eccentric contraction training (ECT) and concentric contraction training (CCT) on the muscle thickness (MT), muscle strength (MS) and delayed onset of muscle soreness (DOMS) of the lower extremities in persons with chronic stroke. Design: Randomized controlled trial. Methods: Thirty persons with chronic stroke were randomly assigned to the ECT or the CCT group. The ECT was performed in a specially designed system of eccentric contraction of both legs and, the CCT was performed using a traditional stepper system for concentric contraction of both legs. The training was performed for 30 min/times, 3 times/wk for 6 weeks. Rehabilitation ultrasound imaging was used to measure MT of the vastus medialis/lateralis (VL), and soleus (SOL), a digital muscle tester was used to measure MS, and a visual analog scale was used to assess DOMS. Results: In the ECT group, MT was significantly improved except for SOL resting (p<0.01). In the CCT group, the MT was significantly improved except for VL contraction (p<0.05). The MS was significantly improved in both groups, especially in the ECT group (p<0.01). In the ECT group, muscle soreness was highest in the first week after training but gradually decreased, and in the CCT group, it was highest in the second week of training but gradually decreased (p<0.01). Conclusions: ECT can improve lower limb MT, MS, and DOMS of chronic stroke survivors. Therefore, it is recommended that ECT be used in the rehabilitation of persons with chronic stroke.

• Physical Therapy Korea
• /
• v.30 no.3
• /
• pp.211-220
• /
• 2023

Background: Smartphone addiction has emerged as a significant social problem. Numerous studies have indicated the association between smartphone use and discomfort in the musculoskeletal system of the upper extremities. Objects: This cross-sectional survey aimed to compare the characteristics of musculoskeletal pain in the neck, trunk, and upper limbs between individuals with smartphone addiction and those without addiction. Methods: We collected a total of 326 healthy individuals' data from China and Korea who had owned and used smartphones for more than 5 years between 20-50s through an online questionnaire consisting of 84 questions in four major sections. The first part contained basic information on the participant's personal characteristics and smartphones. The second part contained questions about smartphone use and posture. The third part was the smartphone addiction. The fourth part was to investigate musculoskeletal pain in various upper body parts. Results: Smartphone addiction has a weak negative correlation with age (r = -0.20, p < 0.01) and a weak positive correlation with the hours of smartphone use (r = 0.376, p < 0.01). Frequent musculoskeletal pain symptoms related to smartphone use were observed in the neck, shoulder, lower back, and wrists. The hours of smartphone use was slightly positively associated with the prevalence of musculoskeletal pain in the shoulder (r = 0.162, p < 0.05) and lower back (r = 0.125, p < 0.05). The prevalence of musculoskeletal pain in the neck (χ² = 3.993, p < 0.05), shoulder (χ² = 6.465, p < 0.05), and wrist (χ² = 4.645, p < 0.05) was significantly higher among females than males. Conclusion: The results suggest that smartphone addiction should be recognized as a dual concern encompassing both physical health and psychosocial aspects. Furthermore, healthcare professionals, including physicians and physical therapists, should consider clients' smartphone usage patterns when assessing and treating with musculoskeletal pain.

• Journal of the Korean Society of Physical Medicine
• /
• v.18 no.4
• /
• pp.89-96
• /
• 2023

PURPOSE: To investigate the effects of the underwater Ai-Chi exercise on the joint range of motion, balance and posture. METHODS: Thirty-six college students (30 men, 6 women) were divided into a 'low physical activity' groups (Group I). and an 'appropriate physical activity' groups (Group II). The Ai-Chi underwater exercise was conducted three times a week for two weeks for both groups. A goniometer was used to measure the range of motion of the hip joint, and Y-Balance and the posture screen mobile were used to measure the stability of the lower extremities. RESULTS: An evaluation of the range of motion of the hip joint before and after the Ai-Chi exercise showed significant results in the low physical activity group. However, the flexural range showed a significant increase after exercise, but not significant result. In the comparison of the mean increase between groups, only the right hip joint showed a significant difference in both groups. Also, in the comparison of the Y balance test and posture screen test before and after exercise, both groups showed significant. CONCLUSION: The Ai-Chi underwater exercise helped improve the range of motion of the hip joint and the ability to balance. Also It helped improve posture alignment. In addition, although the increase in all physical activity groups lower than the appropriate physical activity groups was greater in all figures, the increase in the number of samples, the extension of the experimental period, and various variables could be obtained.