• The Journal of Korean Physical Therapy
• /
• v.30 no.1
• /
• pp.23-28
• /
• 2018

Purpose: This study examined the effectiveness of iliopsoas self-stretching on the hip extension angle, gluteus maximus (GM) activity, and pelvic compensated angle during prone hip extension (PHE) in subjects with iliopsoas shortness. Methods: Twenty-healthy subjects with iliopsoas shortness were recruited. Electromyography (EMG) was used to examine erector spinae (ES), multifidus (MF), GM, and biceps femoris (BF) while performing PHE. An electromagnetic tracking motion analysis device was used to measure the pelvic compensations. The pelvic compensations while performing PHE were considered to be anterior tilting and rotation. A modified Thomas test was used to monitor the hip extension angle before and after iliopsoas self-stretching. A paired t-test was used to investigate the significant difference after iliopsoas self-stretching during PHE. The level of statistical significance was set to ${\alpha}=0.05$. Results: Muscle activity of GM and hip extension angle were significantly greater after iliopsoas self-stretching compared to that before iliopsoas self-stretching during PHE (p<0.05). BF and pelvic rotation angle were significantly lower after iliopsoas self-stretching compared to that before iliopsoas self-stretching during PHE (p<0.05). The muscle activity of ES was not significantly different between PHE before and after iliopsoas self-stretching (p>0.05). Conclusion: Iliopsoas self-stretching can be effective in selectively strengthening the GM muscles with minimized pelvic compensation in subjects with iliopsoas shortness.

• Journal of The Korean Society of Integrative Medicine
• /
• v.8 no.2
• /
• pp.21-27
• /
• 2020

Purpose : The purpose of this paper is to compare the immediate effects of tensor fascia latae (TFL) stretching with weight bearing (standing position) or non-weight bearing (side-lying position). Methods : The study was conducted on 30 adults (12 men, 18 women) in their 20s. Modified Thomas's test was conducted to find out if the TFL muscle has a tightness for current study. This study randomly divided the subjects into two groups and set the standing stretching group (n=15) or the side-lying stretching group (n=15). Both groups applied self-stretching under the therapist's supervision. TFL stretching in each positions was performed 30 seconds per set, 3 times, and 30 seconds per set could rest. The Ober test were conducted to investigate the effect of TFL stretching in each positions. Results : For the Ober test measurements within each group, both groups significantly increased after intervention compared to before (p<.05). There was no significant difference between the groups (p>.05). Conclusion : TFL stretching in standing position and side-lying position increased the range of motion of the TFL muscle. Therefore, if it is difficult to apply TFL stretching in standing position (weight bearing) due to pain or other reasons, it will be able to TFL stretching in side-lying position (non-weight bearing).

• Journal of International Academy of Physical Therapy Research
• /
• v.11 no.3
• /
• pp.2102-2106
• /
• 2020

Background: Static hamstring stretching exercises have been widely used to improve flexibility of the hamstring muscles. However, few studies have examined the influence of standing static hamstring stretching (e.g., jack-knife stretching) on movements of the lumbopelvic-hip complex. Objectives: To examine the short-term effects of jack-knife stretching on movements of the lumbopelvic-hip complex. Design: Case series. Methods: Fourteen participants with hamstring tightness (8 male, 6 female) were recruited. Participants performed jack-knife stretching for 150 s. Before and after stretching, participants performed the finger-to-floor distance (FFD), sit and reach (SRT), active knee extension (AKE), passive straight leg raising (PSLA), and active straight leg raising (ASLR) tests as well as pelvic tilt while standing to identify the effects of stretching. Results: There were significant improvements in the FFD, SRT, AKE, PSLA, and ASLR tests after stretching. However, pelvic tilt angle while standing did not significantly change. Conclusion: Jack-knife stretching can be a useful exercise to improve flexibility of the hamstring muscles, but not pelvic alignment while standing.

• PNF and Movement
• /
• v.20 no.3
• /
• pp.351-358
• /
• 2022

Purpose: This study aims to determine the correlation between the effects of contract-relax-antagonist-contract (CRAC) and contract-relax (CR) forms of proprioceptive neuromuscular facilitation (PNF) stretching on balance during single-leg standing in elderly people. Methods: The participants were 20 elderly people in healthy condition and divided equally into two groups: the CRAC stretching group and the CR stretching group. Subjects were made to walk on a treadmill for 6 minutes before the stretching as a warm-up. CR and CRAC stretching were performed on the soleus. The dependent variables used to assess single-leg standing balance were overall stability(OSI), anterior/posterior(A/P) movement, and medial/lateral(M/L) movement. The statistical methods used to assess the differences between groups were verified using the Mann-Whitney U test and the Wilcoxon signed-rank test. Results: The CRAC group had significantly increased OSI, A/P and M/L after the PNF stretching intervention (p < 0.05). The CR group had significantly increased OSI and A/P after the PNF stretching intervention (p < 0.05), but M/L did not significantly increase (p > 0.05). There was no significant difference in stretching between CRAC and CR (p > 0.05). Conclusion: The results of this study revealed that CR and CRAC PNF stretching improved single-leg standing balance. CARC stretching before exercise is helpful for elderly people, as it improves balance.

• PNF and Movement
• /
• v.20 no.1
• /
• pp.83-90
• /
• 2022

Purpose: The purpose of this study was to investigate the immediate effects of hip flexor stretching with pelvic fixation on the flexibility of hip extension and gait capacity in subjects with limited hip extension flexibility. Methods: Twenty-six subjects with limited hip extension flexibility were divided into two groups: a hip flexor stretching with pelvic fixation group (n = 13) and a hip flexor stretching without pelvic fixation group (n = 13). The subjects were assessed based on flexibility of hip extension, stride, and gait velocity after applying hip flexor stretching. Results: The hip flexor stretching with pelvic fixation group showed significantly improved flexibility of hip extension, stride, and gait velocity compared with hip flexor stretching without pelvic fixation group (p <0.05). The flexibility of hip extension was significantly improved after application of hip flexor stretching in both groups; however, stride and gait velocity were significantly improved only in the hip flexor stretching with pelvic fixation group. Conclusion: Hip flexor stretching with pelvic fixation is an effective intervention for improving the flexibility of hip extension and gait capacity.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.8
• /
• pp.1271-1276
• /
• 2013

This study selected 22 male subjects to examine the maintenance period of static and ballistic stretching applied to rectus femoris, divided them into 11 static stretching group and 11 ballistic stretching group and analyzed changes in median frequency and in maximal voluntary isometric contraction before stretching and at 30 sec, 1 min, 3 min, 5 min, and 10 min after stretching. Median frequency showed significant differences in changes according to time and groups after the test of main effects. It was reduced after 3 min. in both static stretching and ballistic stretching groups and then increased again. Maximal voluntary isometric contraction showed significant differences in changes according to time and groups from the results of the main effect test. Static stretching group was reduced at 3 min after the experiment and then increased after that and ballistic stretching group was reduced at 5 min after the experiment and then increased again. In conclusion, changes were shown according to time after stretching and the effects of ballistic stretching were maintained a little longer than those of static stretching.

• Journal of International Academy of Physical Therapy Research
• /
• v.7 no.1
• /
• pp.919-924
• /
• 2016

In this study, 20 men and women in their 20s were divided into a footboard passive stretching group and a manual passive stretching group. After stretching was applied to the soleus for 5 weeks, a comparative analysis was performed on the range of motion(ROM) of the ankle joint to determine changes in the flexibility of the soleus. Both the footboard stretching group and manual stretching group first performed stretching for 15 sec, followed by a 10-sec break. One set consisted of performing the above process twice consecutively, and each group had to perform five sets in total. A goniometer was used as a measuring instrument. The results of the experiment were analyzed using a nonparametric analysis, Wilcoxon signed rank test, and Mann-Whitney test. SPSS WIN 18.0 was employed for the statistical analysis. In terms of the comparison of the flexibility before and after the experiment according to the different interventions, the application of footboard stretching to the soleus for 5 weeks resulted in $3.2^{\circ}$ right dorsiflexion (p=.009), $6.98^{\circ}$ right plantar flexion(p=.008), $4.14^{\circ}$ left dorsiflexion(p=.005), and $10.97^{\circ}$ left plantar flexion(p=.007), which were all statistically significant increases. The application of manual stretching led to $6.04^{\circ}$ right dorsiflexion(p=.005), $12.14^{\circ}$ right plantar flexion(p=.005), $7.00^{\circ}$ left dorsiflexion (p=.008), and $16.38^{\circ}$ left plantar flexion(p=.005). Therefore, both footboard stretching and manual stretching were effective in enhancing the flexibility of the soleus. However, statistically significant larger increases in the ROM of the ankle joint were observed in the manual stretching group.

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

• PNF and Movement
• /
• v.19 no.2
• /
• pp.195-203
• /
• 2021

Purpose: Neurodynamic tests are used to examine neural tissue in patients with neuro-musculoskeletal disorders, although this has not yet been established in the intensity of nerve tension application. This study aimed to investigate the acute effects of neural stretching intensity on nerve excitability using the latency and amplitude of nerve conduction velocity test (NCV) analysis. Methods: Thirty young, healthy male and female subjects (mean age = 21.30 years) voluntarily participated in this study. Nerve excitability was assessed using the median sensory NCV test. The latency and amplitude of the NCV test were measured under four different conditions: reference phase (supra-maximal stimulus, without neural stretching), baseline phase (2/3 of the supra-maximal stimulus, without neural stretching), weak stretch phase (2/3 of the supra-maximal stimulus, with weak neural stretching), and strong stretch phase (2/3 of the supra-maximal stimulus, with strong neural stretching). Results: The NCV latency was significantly delayed after one minute of neural stretching at the baseline, weak phase, and strong phase in comparison with the reference phase. The NCV latency was significantly delayed by increasing the strength of neural stretching. Furthermore, the NCV amplitude was significantly increased at the weak and strong phases, which were under neural stretching, in comparison with the baseline phase. The NCV amplitude was significantly increased by increasing the strength of the neural stretching. Conclusion: Transient neural stretching as a neurodynamic test can increase the sensitivity of the nerve without negatively affecting the nervous system. However, based on the results of this study, strong neural stretching in the neurodynamic test may delay the transmission of nerve impulses and hypersensitivity.

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