• Carbon letters
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• v.12 no.2
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• pp.107-111
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• 2011

Polyacrylonitrile (PAN) fibers were pre-oxidized in a temperature range of 180-275$^{\circ}C$. The effects of positive and negative stretching on the structure and morphology of PAN fiber in the pre-oxidation process were studied by FTIR spectroscopy, XRD, and SEM. Mechanical property changes were also investigated. No changes in the movement and intensity of functional groups of PAN fibers were caused by positive stretching of up to 10% and negative stretching down to -8%. The crystal structure can be affected by the positive stretching and negative stretching. The maximum strength is 479.81 MPa when the stretching is positive, and the maximum strength is 420.55 MPa when the stretching is negative.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.4
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• pp.19-27
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• 2019

PURPOSE: This study examined which stretching exercise had the most positive effect on increasing the range of motion (ROM) of the knee joint in healthy people and whether there was a difference between continuous stretching and intermittent stretching. METHODS: This study included 30 healthy university students from OOO University. The subjects were asked to sit on a mat and perform hamstring-stretching exercise during which the ROM and muscle tone were measured with pre and post-tests. Each subject was assigned randomly to a continuous stretching group (stretching without relaxation time group, n=10, G1) or intermittent stretching group (stretching with 10s relaxing time group, n=10, G2; and stretching with 20s relaxing time group, n=10, G3). The participants conducted hamstring stretching exercises with a sit-and-reach box at three different rest times (0s, 10s, and 20s). Subsequently, they underwent passive knee extension (PKE) tests, in which the ROM of the knee joint was measured with a goniometer, and the muscle tone was evaluated using a MyotonPro. RESULTS: Significant differences in muscle tone, stiffness, and ROM were observed between pre-test and post-test in each groups (p<.05). Although the post hoc tests indicated no significant differences in muscle tone and ROM between the continuous stretching group and intermittent stretching group (p>.05), the rate of change of the ROM showed that the intermittent stretching group developed more effective maintenance of the hamstring flexibility. CONCLUSION: No significant differences in the muscle tone of the hamstring and ROM of the knee joint were observed according to the hamstring stretching exercises with three different rest times. On the other hand, the rate of change of the ROM showed that intermittent stretching maintained the hamstring flexibility more effectively.

• Physical Therapy Korea
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• v.26 no.4
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• pp.63-69
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• 2019

Background: Both the rapid concentric and eccentric contractions during exercise repeatedly impose excessive stress on muscle tissue. The hamstring muscles are very susceptible to injury due to the tensile stress. Various interventions are currently being undertaken to prevent strain injury before exercise. Stretching is the most common method and is known to have a positive effect on flexibility and muscle performance. However, relatively few studies have investigated the potential negative factors of stretching. Objects: The purpose of this study was to examine changes in pain following the different intensity of the stretching and types of physical stress. Methods: The subjects were divided into three groups based on the intensity of stretching: 100% (S100), 75% (S75), and 50% (S50) of the measured force at the point of discomfort in static stretching and 100% (P100), 75% (P75), and 50% (P50) of the maximum voluntary isometric contraction in Proprioceptive Neuromuscular Facilitation (PNF) stretching. The pain individual subjects perceived after stretching was measured via a Visual Analog Scale (VAS) and compared between the groups Results: Despite the decrease in the intensity of static stretching, no decrease in VAS value was observed. In PNF stretching, a significant decrease was observed at P50 compared to P100. S100 was significantly higher than P75 and P50. Conclusion: Previous studies have shown that PNF has a superior or the same effect on flexibility in comparison with static stretching. This effect was maintained even in moderate intensity. PNF stretching performed under moderate rather than high intensive static stretching, which causes pain and discomfort, might be recommended in clinical settings.

• The Journal of Korean Physical Therapy
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• v.17 no.4
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• pp.559-567
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• 2005

The purpose of this research is to study how the stretching exercise along with heat and electric therapy can effect on Angle of Lumbar Flexion and Reduction of Pain against the Hamstring Construction Symptom that can be found in the Chronic Low Back Patients. The target of research was 28 person selected out of the patients diagnosed as Lumbar Sprain and Lumbar Syndrome, who have positive from the active test of Hamstring construction and passive test. Their age range is 20 to 60 years old, 14 male and 14 female. As a research method, simple heat and electric therapy was applied to counter part while Hamstring Stretching Exercise including simple heat and electric therapy was applied to the experimental part. After 6 weeks treatment for each part, the results of effect on Angle of Lumbar Flexion and Pain Reduction was compared and analysed on the basis of the gravity angle meter and Visual Analogue Scale (VAS). The outcome of research is as follows: 1. Angle of Lumbar Flextion increased effectively not in the conventional counter group but the experimental group to which Hamstring Stretching was applied simultaneously. 2. remarkable effect was shown in the experimental part applied Hamstring Stretching. Consequently from the results of this study, we could find out the fact that the therapy combined preserve treatment and hamstring stretching not only produced increasing Lumbar Flexion Angle but also was more effective on reducing pain of the patients according to it than the conventional or preserve therapy.

• Physical Therapy Korea
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• v.16 no.1
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• pp.34-41
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• 2009

The purpose of this study is to compare the outcomes of manual stretching treatment with those of motor development and positioning physical therapy (MDPPT) for congenital muscular torticollis (CMT). This study was designed to be randomized controlled trials and to evaluate the outcomes of 43 consecutive patients with CMT who were first seen when they were average 26 days old. Before treatments, the patients were unintentionallv classified into two clinical groups along with the treatment methods. Among the 43 patients, 22 were classified to the manual stretching group and 21 to the MDPPT group. By means of independent t-test on the result. the duration of treatment according to methods was not significantly different in two groups (p>.05). The duration of treatment in accordance with head tilt level was not significantly different in two groups (p>.05). There was change of mass diameter, between at the beginning day of treatment and after treatment in manual stretching group with a strong positive linear correlation (p=.000, r=.734), but slightly positive linear correlation in MDPPT group. The result of this study indicates that two therapeutic methods make little difference in effectiveness.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.525-535
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• 2016

The purpose of this study was to evaluate the effect of thoracic dynamic stretching with elastic band on the ROM and ball speed for baseball player. For this purpose, 11 baseball players of the I city high school and university performed thoracic dynamic stretching with elastic band before throwing a ball. After stretching, we measured the ROM and ball speed and compared. The results were as follows. First, ROM after stretching showed a significant increase immediately compared with before stretching. Second, the speed of the ball was significantly increased after stretching compared with before. These results indicated that thoracic dynamic stretching with elastic band for baseball players might have a positive effect on ball speed as well as ROM.

• The Journal of Korean Physical Therapy
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• v.31 no.5
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• pp.266-272
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• 2019

Purpose: This study compared the effects of Static stretching and Mulligan's Two-leg rotation about the Hamstring flexibility, Hip range of motion, and pain. Methods: The subjects were allocated randomly into two groups: Static stretching group (n=13) and Mulligan's two leg rotation group (n=14). The study was designed with stretching protocols for four minutes and thirty seconds per day five times a week for three weeks in total. Measurements, including the Sit and reach test, Active/Passive Straight leg raise, and Visual analogue scale, were conducted before and after the intervention. The data were analyzed using a paired t-test and independent t-test. Results: The flexibility of the two leg rotation group was higher than the static stretching group after the intervention. The post-sit and reach test value of the two leg rotation group was significantly higher than the pre-sit and reach test value of the static stretching group. In addition, the variance of the sit and reach test of the two leg rotation group was significantly higher than that of the static stretching group. Conclusion: These results showed that two leg rotation techniques have a positive effect on the changes in the sit and reach test and active straight leg raise test. Two leg rotation techniques can be recommended as a self-stretching and easier way to stabilize the lumbopelvic rhythm, reduce the stiffness of the muscle and relieve pain. This is effective in preventing muscle damage, enabling muscle relaxation and reducing the risk of injury to the spine during daily lives and in sports activities.

• Korean Journal of Occupational Health Nursing
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• v.24 no.1
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• pp.11-18
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• 2015

Purpose: The purpose of this study was to test effects of fatigue reduction program for women workers at a food production company. Methods: A quasi-experimental design was conducted. Eighteen workers in vitamin E group, 16 workers in vitamin E and stretching group, and 18 workers in stretching only group participated. Participants were evaluated at baseline and 8 weeks. Results: The results showed that stretching only group had a significant impact on reducing of fatigue level compared to those of a vitamin E group. Conclusion: Although vitamin E supplement has not shown decreasing fatigue level, the positive effect of stretching exercise may have high applicability to a workplace.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.93-99
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• 2018

The purpose of this study was to prove the effect of passive stretching after delayed muscular pain induction in university students and to propose a rehabilitation exercise program for effective pain relief and prevention in case of injury. Subjects were divided into passive stretching group and control group. Passive stretching group was performed passive stretching after delayed muscular pain induction and control group did not perform any treatment after delayed muscular pain induction. The delayed muscular pain induction method was induced by bench step motion. The height of the step box was 50cm. The data were analyzed by two-way RGRM ANOVA for comparison of passive stretching group and control group. In conclusion, passive stretching after delayed myalgia has a positive effect on blood fatigue (CRP, LDH) and subjective pain scale(VAS).

• Korean Journal of Applied Biomechanics
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• v.28 no.4
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• pp.207-211
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• 2018

Objective: The purpose of this study was to examine the effects of an 8-week SMR, stretching, and band program on lower limb alignment (distance between the knees, Q angle) and gait (gait speed, stride length, impulse, and peak pressure) in female in their 20s who have genu varum. Method: The participants, female in their 20s who had genu varum, were randomly divided into the SMR, Stretching, and Band group (SSB, n=9), Stretching and Band group (SB, n=9), and Control Group (CG, n=9). Experimental group A (SSB) performed 3 50-minute sessions of the program per week for 8 weeks while the experimental group B (SB) performed stretching and band correctional exercise in 3 40-minute sessions per week for 8 weeks. The control group had no correctional exercise program. Results: Only the SSB group showed a significant increase in gait velocity and stride length in this study. The SSB and SB group showed a significant decrease of impulse on the forefoot after exercise program suggests that SMR and elastic band exercise had a positive effect on the distribution of foot pressure. Conclusion: We concluded that 8-week genu varum correctional exercise program had beneficial effects on the gait parameters (gait velocity, stride length, impulse, peak pressure) in 20s women with genu varum.