• Physical Therapy Korea
• /
• v.2 no.1
• /
• pp.44-50
• /
• 1995

The purpose of this study was to investigate which of 4 positions produced the highest action potential in the rectus femoris muscle of normal adult subjects. Testing was performed in supine with the right leg performing a simple straight leg raise with the knee fully extended. The left leg, however, was placed in 4 different positions: 1. Full support with $0^{\circ}$ flexion. 2. Flexed on the plinth with $60^{\circ}$ knee flexion and foot flat. 3. Same as N0.2 but with $90^{\circ}$ knee flexion. 4. Left leg hanging over the end of the plinth with $90^{\circ}$ knee flexion, $0^{\circ}$ hip flexion and no foot support. This study was designed to compare the level of electromyographic activity of the rectus femoris under 4 positions. Fourty-three healthy young adults performed three trials of each exercise condition in random order in the supine position. Electromyographic activity was recorded from surface electrodes. Rectus femoris action potentials in all 4 positions were significantly different. The highest action potential at the end of movement of the right leg occurred with the left leg hanging over the end of the plinth with $90^{\circ}$ knee flexion. It is therefore recommended the straight leg raising be performed with the contralateral leg flexed at $90^{\circ}$ over the end of the supporting surface to obtain a maximum rectus femoris isometric contraction.

• Korean Journal of Applied Biomechanics
• /
• v.25 no.3
• /
• pp.257-263
• /
• 2015

Objective : The purpose of this study was to investigate the effect of genu valgum on the body mass index, movement of lower limb joints, and ground reaction force. Methods : Gait patterns of 30 college students with genu valgum were analyzed and the static Q angle of the femur was measured for selecting genu valgum of the subjects. To analyze the kinetic changes during walking, the six-camera Vicon MX motion analysis system was used. The subjects were asked to walk 12 meters using the more comfortable walking method for walking. After they walked 12 meters more than 10 times, their most natural walking patterns were chosen three times and analyzed. Results : As a result of measuring a relationship between genu valgum and Q-angle, as the Q-angle increases, it showed a genu valgum also increased. Body Mass Index showed a significant difference between the groups was higher in the genu valgum group.(p<.001). The analysis result showed that genu valgum had a significant effect on the internal rotation moment in the hip joint(p<.05). Also, genu valgum had a significant effect on the internal rotation moment of the knee joint(p<.05). The comparative analysis of the Medial-Lateral ground reaction force in the genu valgum group showed a tendency to increase the medial ground reaction force(p<.05). The vertical ground reaction forces of the middle of the stance phase(Fz0) showed a significant increase in genu valgum group(p<.05), in particular the results showed a decrease in the early stance phase(p<.001). Conclusion : In conclusion, the change in body mass is considered to be made by proactive regular exercise for improvement of the genu valgum. In addition, the prevention of the deformation caused by secondary of the genu valgum in this study may be used as an indicator of the position alignment rehabilitation for structural and functional improvements. Applying a therapeutic exercise program for the next lap will require changes in posture alignment.

• Physical Therapy Korea
• /
• v.9 no.1
• /
• pp.1-15
• /
• 2002

The purpose of this study was to compare the balance and gait between fallers and non-fallers in elderly. A brief questionnaire was used to obtain the fall history. Twenty-seven women subjects were evaluated in this study. Eleven subjects and a mean age of 84.5 years (SD=4.6) were designated as the faller group. Sixteen subjects and a mean age of 80.3 years (SD=5.3) were designated as the non-faller group. The fall-related factors (mental status, balance, range of motion and muscle strength of lower extremity, sensation of foot, and cadence, walking velocity, stride length) were compared between faller group and non-faller group and measured. The results showed that faller group had significantly less range of motion of the hip flexion and knee extension, and strength of the knee extensor and ankle dorsiflexor and plantar flexor than non-faller group. The scores of the Functional reach test and One leg standing were significantly less in faller group than in non-faller group. Faller group showed less walking velocity and stride length compared to non-faller group. However, there was no significant difference in cadence during comfortable waking and fast walking between two groups. There were no significant differences in pressure, position sensory between two groups. These results suggest that exercise for improving the flexibility, muscle strength of the lower extremity and balance may be useful strategies to prevent fall in elderly. Further studies are needed to identify which specific factors are related to fall in the elderly population.

• Physical Therapy Korea
• /
• v.6 no.3
• /
• pp.11-21
• /
• 1999

Human balance is maintained through a complex process involving sensory detection of body motions, integration of sensorimotor information within the central nervous system, and execution of appropriate musculoskeletal responses. The basic task of balance is to position the body center of gravity (COG) over some portion of the support base. When the COG extends beyond the base of support, the person has exceeded the limits of stability (LOS). At this point, a step or stumble is required to prevent a fall. Automatic postural responses operate to keep the COG over the base of support. They are a set of functionally organized, long-loop responses that act to keep the body in a state of equilibrium. There are four commonly identified automatic postural responses, or strategies. These are ankle strategy, hip strategy, suspensory (knee) strategy, and stepping strategy. Thus, the purpose of this study was to evaluate the LOS using various knee strategies. Forty subjects participated in this study. The subjects were comprised of 20 males and 20 females who were without neurologic, orthopaedic or balance performance impairments. The LOS was measured with a Balance Performance Monitor (BPM) Dataprint Software Version 5.3. The results of this study were as follows: 1) Knee joint angle which is to increase stability of standing balance with using knee strategy was at mid-range. 2) There were statistically significant differences in anteroposterior LOSs according to the knee strategy. 3) There were no statistically significant differences in mediolateral LOSs according to the knee strategy. 4) There were statistically significant differences of anteroposterior LOSs with using knee strategy according to gender. 5) There were no statistically significant differences in mediolateral LOSs with using knee strategy according to gender.

• Korean Journal of Applied Biomechanics
• /
• v.26 no.3
• /
• pp.243-248
• /
• 2016

Objective: The aim of this study was to determine the kinematical characteristics of somersault with twist in the Lou Yun and Akopian motions and to provide useful information to gymnastic athletes in men's vault. Method: The study subjects were 12 male adult top athletes. After 12 trials (7 Lou Yun and 5 Akopian trials) filmed by using two digital high-speed camcorders set at 90 frames/sec, kinematical data were collected through the direct linear transformation (DLT) method. The mean differences in biomechanical variables were compared during the second flight upward phase. The kinematic characteristics of somersault with twist in the Lou Yun and Akopian motions were identified. Results: In Lou Yun motion, the vertical release velocity through horse breaking was not difficult to obtain, so the athletes had enough time to prepare for the twist. Therefore, the Lou Yun motion has an advantage to make a cat twist in the pike posture. In the Akopian motion, obtaining the horizontal velocity through horse pushing was so easy that the Akopian athletes attained a large angular impulse and angular momentum. Therefore, the Akopian motion has an advantage to making a tilt twist in the body tilting posture. Conclusion: This study suggests that gymnastic athletes should control their body segment movements in order to increase the twisting angular velocity of the whole body, which requires regulation of the longitudinal moment of inertia of the body. Moreover, athletes should prepare for the shoulder and hip twists early in order to make the landing position in advance.

• Journal of Korean society of Dental Hygiene
• /
• v.9 no.2
• /
• pp.45-56
• /
• 2009

The purposes of this study were to investigate the relationships between the degree of physical pain and the knowledge and preventive actions of musculoskeletal diseases among dental hygiene students with a potential risk of contracting those diseases and thus to help them prevent them. A survey was taken among 207 sophomores and juniors specializing in dental hygiene at S1 and S2, Gyeonggi Province in the area of physical pain, knowledge of musculoskeletal diseases, and preventive actions against them. The findings were as follows: 1. The mean scores of the sophomore in the knowledge of musculoskeletal diseases were $6.20{\pm}2.21$, and those of the juniors were $6.72{\pm}2.29$. The mean scores of the sophomores and juniors in the preventive actions against musculoskeletal diseases were $22.50{\pm}2.37$ and $22.29{\pm}3.01$, respectively. 2. The subjects displayed severe physical pain in the lower back, shoulder, and neck in the descending order and medium physical pain in the neck, shoulder, and lower back in the descending order. 3. The higher level knowledge of musculoskeletal diseases they had, the less physical pain they felt. And there were significant differences among the shoulder, lower back, hip, ankle, and foot. 4. There were relationships between physical pain and the preventive actions against musculoskeletal diseases in "placing the hands at the height of the elbows during treatment", "reducing such positions as bending and extending during treatment", "narrowing the distance with the patient", "taking regular breaks during treatment for recovery", "trying not to incline the neck, back, arm, and wrist as much as possible", and "trying to keep the torso in the neutral position." 5. As for the education about musculoskeletal diseases, 74 sophomores(88.10%) and 102 juniors(89.74%) answered they received no such education. The results suggest that there should be some instructions to help dental hygiene students practice the preventive actions against musculoskeletal diseases and further prevention programs against those diseases.

• Journal of Korean Medicine Rehabilitation
• /
• v.19 no.2
• /
• pp.289-302
• /
• 2009

Objectives : This study was performed in order to investigate the relation of body composition analysis and radiological parameter(lumbosacral angle, lumbar lordortic angle, lumbar gravity line). Methods : This study was carried out with the data from comprehensive medical testing. 75 subject aged 20-59 performed the segmental bioelectrical impedance analysis, questionnaire. And lumbosacral angle, lumbar lordortic angle and lumbar gravity line were measured in the standing position x-ray. Then we analyzed the data. Results : Low back pain(LBP) prevalence in high obesity index(Body Mass Index(BMI), Percentage of Body Fat(PBF), Waist Hip Ratio(WHR)) group was higher than LBP prevalence in normal obesity index group(p<0.01). In LBP group, lumbosacral angle, lumbar lordortic angle were significantly lager than Non-LBP group(p<0.001). And 75% of LBP group indicated abnormal lumbar gravity line ratio(0.67 < Normal lumbar gravity line ratio <1.00). When it comes to analyze relation between obesity index and radiological parameter, no-significant change was seen. Conclusions : This study carried as following research after the study on relation of obesity, LBP and trunk muscle strength. Results from this investigation showed positive correlation between obesity and LBP prevalence. But obesity index didn't indicate significant correlation with structural changes of lumbar vertebrae. When considering prior research, trunk muscle strength changes were more related to LBP prevelence in obese people. This results are expected to explain causes of LBP in obese group.

• The Research Journal of the Costume Culture
• /
• v.14 no.3 s.62
• /
• pp.387-403
• /
• 2006

The purpose of this study was to develop a new torso pattern for the schoolgirl of a tween generation who had different somatotype from children and teenagers. The subjects in this study were female elementary school students of fifth or sixth grade. Through a sensory evaluation of four existing torso patterns, the first research torso pattern was developed. Drafting methods of each item, which closed to the optimum value three, were selected. The differences between the values of the selected drafting methods and the optimum three were verified through a Wilcoxon's ranked sum test. The final research torso pattern was developed through adjusting the drafting methods according to the deviation from the optimum value three. The schoolgirl of a tween generation is at the time to show the remarkable breast development compared with a waist circumference, so the bust drafting was defined as B/4+ 1.25cm separately front and back. The drafting of a waist circumference was defined as W/4+1cm separately front and back which taken the ease amounts of the somatotype into consideration of the schoolgirl of a tween generation. A princess line was used instead of a waist dart because their hip circumference was more developed than a waist circumference. The crossed amount of a front hemline was 0.3cm and that of a back hemline was 0.7cm. and the princess line of the position was drawn with a straight line at a right angle of the back waistline. The armhole depth was determined B/4-1cm in consideration of the aesthetic and the trend, although the effective movement of upper arm was required.

• Journal of Korean Academy of Nursing
• /
• v.24 no.1
• /
• pp.115-128
• /
• 1994

The purpose of this study was to observe the change of circumference, volume and strength of normal and operated lower extremities on 3rd, 7th, 10th, and 14th days of postoperation following THRA compared with their condition on preoperation day. Subjects consisted of 13 male and 7 female Patients operated with THRA between the age of 20 and 69 years with a mean age of 38.55(SD=15.1). Circumference of upper and lower leg was measured by tape, leg volume was determined according to formula (Moor & Thornton, 1987) with measurement of 8 circumferences of leg. Leg strength was measured by pressing the center of digital health meter in supine position. The results can be summarized as follows : 1. Circumference of operated thigh decreased significantly at 14 following THRA compared with preoperative value, while that of normal thigh decreased significantly at day 3, 7, 10 and 14 after THRA compared with preoperative value. 2. Circumference of midcalf in both operated and normal limb decreased significantly at day 3, 7, 10 and 14 following THRA compared with preoperative value. 3. Leg volume of operated lower limb decreased significantly at 10, 14 following THRA compared with preoperative value, while that of normal limb decreased significantly at day 7 & 10 after THRA compared with preoperative value.4. Leg strength of operated limb decreased significantly at day 3, 7, 10, 14 following THRA compared with preoperative value. No significant difference of normal leg strength was shown following THRA. 5. Circumference of midcalf differed significantly at day 14 after THRA between normal and operated extremity. From these results, it can be suggested that a decreased activity after THRA caused muscle atrophies in normal and operated extremity.

• Journal of the Korean Dietetic Association
• /
• v.22 no.3
• /
• pp.214-224
• /
• 2016

The purpose of this study was to assess the physical activity of preschool children using an accelerometer and investigate differences related to epoch length setting during use of the accelerometer. Subjects of the study were 26 children (12 boys and 14 girls) at the age of 5, enrolled in one preschool located in Gangneung. From 9:00 a.m. to 4:00 p.m. (7 hours period), every child wore a total of four accelerometers (ActiGraph $GT3X^+$, USA), including three attached to the left hip (with epoch length set at 5 seconds, 15 seconds, and 30 seconds). For comparison purposes, a forth was attached to the opposite position, with epoch length set at 5 seconds. Data collected using 15s epoch and 30s epoch (single larger epoch) were compared with those obtained after reintegration of 5s to 15s epoch, 5s to 30s epoch, and 15s to 30s epoch, respectively (smaller epochs reintegrated). According to the results of this study, there were no significant differences in VM between 30s epoch and 5s to 30s epoch reintegrated and in MVPA (moderate-to-vigorous physical activity), between 15s epoch and 5s to 15s epoch reintegrated. From the Bland-Altman plot, reintegration of 15s to 30s epoch in VM and reintegrations of 15s to 30s epoch and 5s to 15s epoch in MVPA can be recommended for assessing physical activity in preschool children. Further research is needed into the reintegration method while using an accelerometer for assessment of energy expenditure in children.