• Korean Journal of Applied Biomechanics
• /
• v.22 no.3
• /
• pp.325-332
• /
• 2012

This study aimed to analyze the effects of external load between male and female on angular velocity, moment, and absorbed energy of the lower-extremity joints during drop landing. The study subjects were 9 male($mass=70.82{\pm}4.64kg$, $height=1.71{\pm}0.04m$, $age=24.5{\pm}1.84years$), 9 female($mass=50.14{\pm}4.09kg$, $height=1.61{\pm}0.03m$, $age=23.6{\pm}2.62years$), without any serious musculoskeletal, coordination, balance, or joint/ligament problems for 1 year before the study. The angular velocity, flexion/extension and abduction/adduction moments, and absorbed energy of the lower-extremity joints were compared between the men and women during drop landing under 4 different conditions of external load(0%, 8%, 16%, and 24%) by using two-way repeated ANOVA(p < .05). The women landed with a greater peak angular velocity of the ankle joint, greater peak inversion moment, and lower peak hip-extension moment than the men did, under all 4 conditions. Additionally, the landing characteristics of the women were distinct from those of the men; the women showed a greater peak knee-adduction moment and greater absorbed energy of the knee joint. These differences indicate that anterior cruciate ligament(ACL) strain was greater in the women than in the men and therefore, women may be at a higher potential risk for noncontact injuries of the ACL with an increase in external load.

• Korean Journal of Human Ecology
• /
• v.17 no.1
• /
• pp.115-126
• /
• 2008

The construction of an athlete's tight-fitting garments is very important to the wearer in terms of athletic performance. Therefore pattern development of tight-fitting garments must allow for the full range of human movement and postures. In this study the relationship between the construction of a skate pants pattern and clothing fitting was explored with the aim of improving the comfort of the clothing. The four male subjects were university students between the ages of 20 to 24. Subjective wear sensations of the experimental garments were rated using a seven-point Likert scale on four consecutive days. While wearing the garments, subjects were asked to take five different postures including waist flexion, sitting and others. A Likert-type scale was used for the evaluation, with 7 points indicating the best fit in tight-fitting pants. Results showed differences in the front-rise length and back-rise length between basic pants(A) and modified pants(B,C,D) were -5.16cm and +5.64cm. Comparing the basic pants pattern(A) with modified pants pattern(B), the latter was superior to basic pants(A) in terms of pressure sensation and closeness of fit, but there was no significant difference. Among the four tight-fitting skate pants, A and B pants were superior to the others in terms of fitting and stability of waist and hip sections. In the case of the skate pants, the number of cutting lines in the pattern had an influence on clothing comfort. A minimum cutting line for tight skate pants was better than a maximum cutting line in terms of clothing comfort.

• Korean Journal of Applied Biomechanics
• /
• v.18 no.4
• /
• pp.179-189
• /
• 2008

The purpose of this study was to investigate interjoint and intersegmental coordination of lower segments in skill process. For the investigation, we examined the difference of resultant linear velocity of segments and angle vs angle graph. Novice subjects were 9 male middle school students who have never been experienced a taekwondo. We analyzed kinematic variables of Side Kick motion through videographical analysis. The conclusions were as follows. 1. Examining the graph of novice subjects' maximal resultant linear velocity of the thigh, shank, and foot segment, as it gets closer to the end of the training, the maximal resultant linear velocity in each segment increases which can be assumed to be a result of the effective momentum transfer between adjacent segments. 2 This research showed a sequential transfer from trunk, to thigh, and then to shank as it gets closer to the end of learning at intersegment angular velocity, and it also showed pattern of throwlike motion and pushlike motion. 3. In three dimension of flexion-extension, adduction-abduction and internal-external rotation of the thigh and shank segment, the angle-angle diagram of knee joint and of hip joint showed that dynamic change was indicated at the beginning of learning but stable coordination pattern was indicated like skilled subject as novice subjects became skilled.

• Physical Therapy Korea
• /
• v.9 no.3
• /
• pp.47-65
• /
• 2002

This study examined the correlations among the Berg Balance Scale, which is a clinical tool used to evaluate balance ability, spatiotemporal parameters of gait, and falling; determined the parameters most closely related to falling; and identified a discriminatory parameter and its predictability. Thirty-four subjects aged 72 to 92 years participated in this study. Following a questionnaire survey about falling, the Berg Balance Scale and spatiotemporal parameters of gait were measured. The results revealed that the incidence of falls increased with aging and an accompanying reduction in the flexion range of motion of the hip joint. The gait characteristics of elderly people who fell easily included a slower walking speed, shorter stride, and longer stance time than other elderly. When the cutoff score was set at 45, the Berg Balance Scale was able to identify correctly those individuals who truly have experience of falling than when the cutoff score was set at 39. But when the cutoff score was set at 39, the scale's specificity identifying correctly those individuals who truly have not experience of falling was higher than at the cutoff score of 45. Therefore, the Berg Balance Scale is an appropriate screening method in a clinical setting for the early detection of elderly people at risk of falling. In conclusion, elderly people with a Berg Balance Scale score. below 45 are the most likely to fall owing to their decreased balance ability.

• 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.

• Korean Journal of Human Ecology
• /
• v.24 no.2
• /
• pp.255-266
• /
• 2015

In this study, we have developed the ergonomic pattern from the 3D human body reflecting cycling posture and extensibility of the stretch fabrics. Adjusting pressure level in the construction of athlete's tight-fitting stretch garments by reducing the original pattern is a challenging subject, which influence on the performance of the wearer directly. Therefore, in this study, relationships between the reduction rates of the 2D pattern obtained from the 3D human scan and resultant clothing pressure were explored to improve the fit and pressure exerted by reduced clothing pattern. Subjective wear sensations of the experimental garments were rated using a seven-point Likert scale on two consecutive days. While wearing the garments, subjects were asked to take five different postures including waist flexion, sitting and others. A Likert-type scale was used for the evaluation, with 7 points indicating the best fit in tight-fitting pants. Comparing 2/3T-pattern with T-pattern, the latter was superior to 2/3T-pattern in terms of adhere well to the waist and hip area in the 0.032 significance level. T-pattern was superior to 2/3T-pattern in terms of fitting and wear comfort. As results, the pattern obtained from the flexed body reflecting cycling posture already included the contraction and extension of the skin while cycling posture, so that the extra ease for movement and good fit was not need to be considered. The optimized reduction rates were determined with the proposed reduction rate, the resultant pressure range was within the range of $0.5{\sim}3.0gf/cm^2$ at eight locations on the body except front waist band and thigh band.

• Journal of Korean Physical Therapy Science
• /
• v.16 no.1
• /
• pp.11-20
• /
• 2009

Background: The purpose of this study was to investigate the effect of stretching and strengthening exercise on the static flexibility and pain intensity for the iliopsoas muscle, which is one of the main reasons for the chronic low back pain. Methods: The subjects of this study were 15 male adult patients with showed 6 score or higher in the visual analogue scale(VAS) and complained of low back pain over three months who visited department of the physical therapy, KIA motors Industrial Health Center, from October, 2008 through December, 2008. Fifteen subjects were trained stretching, mat exercises and sling exercises for iliopsoas muscle at 4-5 times a week for 4 weeks. I measured the changes on the extensibility of iliopsoas muscle, static flexibility of low back and VAS between pre- and post exercise treatment. Date were analyzed using the Wilcoxon's signed rank test considering the size of the samples. Results: 1. The angle of the hip joint that showed the extensibility of iliopsoas muscle was relieved, which was significant statistically (p<.05). 2. The static flexibility was statistically significantly improved in the trunk flexion test, trunk extension test and Schober-Test (p<.05). 3. The VAS showed decrease, which is significant statistically (p<.05). Conclusion: It is believed that the exercise treatment of iliopsoas muscle has the significant effects on the improvement of static flexibility and decrease of pain intensity for the chronic low back pain patients.

• Journal of Korean Physical Therapy Science
• /
• v.24 no.2
• /
• pp.45-52
• /
• 2017

Purpose : Most of the moderns have been spent sedentary life style in front of desk or on the chairs, so that their hamstring muscles are shorted commonly and the shortness of hamstring muscles are caused to some problems in functional activities. The purpose of this study was to compare the effectiveness of thermotherapy with hot-pack and ultrasound on the tightness of hamstring muscles in individuals with hamstring tightness. Method : Twenty-eight persons with hamstring tightness participated in this study. They were randomly assigned to three exercise groups: stretching group(n=10), hot-pack group(n=9), and ultrasound group(n=9). Before experiment, this study measured the angle of hip flexion using a inclinometer in all participants. Stretching group conducted actively stretching on their shorted leg for 30 seconds, 3 times, and rest for 10 seconds between each exercises. Hot-pack group have applied hot-pack($70{\sim}75^{\circ}C$) on shorted hamstring muscles for 20 minutes before stretching exercise. Ultrasound group have applied therapeutic ultrasound(1 MHz and 1.5W/cm2) on shorted hamstring muscles for 10 minutes before stretching exercise. All data was analysed using one-way repeated ANOVA. Result : The results revealed that ultrasound therapy before stretching is more effective to the flexibility on hamstring muscles than hot-pack before stretching and stretching only. Conclusion : The results of this study show that thermotherapy with therapeutic ultrasound will be effective on the shortness of hamstring muscles before stretching exercise.

• Korean Journal of Applied Biomechanics
• /
• v.19 no.1
• /
• pp.107-115
• /
• 2009

The purpose of this study were to investigate the effects of muscle, balance and walking training on muscle, balance and gait kinematics in children with Down syndrome. Nine children ($9{\sim}12$ years old) with Down syndrome participated in this study. The participant with Down syndrome participated in muscle, balance and walking training for 12 weeks, three times a week Kinematic variables of gait were measured 3-dimentional motion capture system. The results indicated that the pelvis rotation decreased, the knee and hip flexion increased, decreased leg sway during the swing phase, the cadence increased, and the stride length decreased after the muscle, balance and walking training. In conclusion, Down syndrome's gait kinematic variables improved after the muscle, balance and walking training.

• Journal of Korean Physical Therapy Science
• /
• v.10 no.1
• /
• pp.7-17
• /
• 2003

The purpose of this study was to investigate the effect of the involved lower limb weight bearing training on symmetrical weight supporting rate improvement and gait characteristics of patients with hemiplegia including their gait velocity, cadence, stride length, step length of the non affected side, step length of the affected side, foot angle of the non affected side, foot angle of the affected side, base of support, and so on. The subject of the study was 28 men and women patients with hemiplegia from 22 to 77 age, among patients who doctor diagnosed as hemiplegia due to stroke or traumatic brain injury, were possible to do independent gait more than 45m without others assistance, the flexion contracture of hip pint was less than $15^{\circ}$, did not have contracture for knee pint and one more than $5^{\circ}$ for ankle joint, did not have contraindication for exercise or gait did not show visual defect due to brain injury. The patients, the subject of the study, were classified into 14 patients of treatment. group applying continuous involved weight bearing with general therapeutic exercise and 14 patients of control group applying general therapeutic exercise, and then analyzed their gait before and after exercise. Temporal distance gait analysis(Boening, 1977) was used to analyze their gait, and ink foot-print was applied as one of measurement methods. However, it was statistically signifiant in the change rate(%) of gait characteristics, and treatment group's patients with hemiplegia had been highly changed in gait characteristics in comparison with control group. From the above-mentioned results, could find that continuous involved weight bearing training for patients with hemiplegia was effective to improve their gait ability and it could increase the ability in comparison with general exercise.