Background: Muscle thickness (MT) measurement using ultrasound image is emerging as a useful method to assess muscle mass during stretching. Traditionally, range of motion (ROM) measurements assessed by digital inclinometer are considered reliable and valid parameter for monitoring muscle flexibility. The ultrasound-based measurement for MT to monitor muscle flexibility has yet to be validated. Objects: This study aimed to determine whether ultrasound measurement can serve as a valid alternative to a digital inclinometer for assessing muscle flexibility following stretching interventions. Methods: A randomized crossover design study was conducted with 20 healthy young participants. The stretching exercise program was carried out passive static and hold-relax proprioceptive neuromuscular facilitation stretching exercises applied on gastrocnemius-soleus muscle group with 3 times a week for 2 weeks. Data were collected 3 times for pre- and post-tests. Dorsiflexion ROM was measured by a digital inclinometer and the MT of gastrocnemius muscle by the ultrasound. Intraclass correlation coefficient (ICC) analysis for test-retest reliability, Wilcoxon sign rank test for stretching effects, and Spearman’s correlation analysis for determining the concurrent validity of two measurements. Results: ICC values of pre- and post-tests in both ROM and MT measurements were showed good to excellent intra rater reliabilities ranging from 0.782 to 0.968 (p < 0.001). A significant increase in the ROM measurements was observed following the stretching program (p < 0.01), whereas no significant change in the MT measurement was showed. Spearman’s correlations revealed weak relationships between the ROM and MT measurements (r = –0.217 for pre-test, r = –0.259 for post-test, r = –0.282, p < 0.05 for changes). Conclusion: These findings suggest that both the MT and ROM measurements were not compatible for monitoring muscle flexibility following stretching exercises regardless of their good reliabilities. Further investigations may be required to the MT measurement alone to be an alternative method.

Background: When shorter muscles are restored to normal, non-specific low back pain, which is the mechanism that causes pain along with muscle relaxation, disappears. Among the stretching methods, self-stretching is a good exercise method not only for treatment but also for preventive purposes. Objectives: To find out what is the most effective method of self-stretching, which is often used in treatment and preventive arbitration, which can reduce muscle activity and increase spinal flexibility in patients with non-specific back pain. Design: Randomized controlled trials. Methods: Three self-stretching exercise methods for erector spinae are randomly assigned to 13 people each, and three self-stretching exercise methods are performed for each study subject. Surface electromyography using, was performed to measure the erector spinae muscle activity. flexibility was measured through Trunk flexion test in a standing position. Muscle activity and flexibility were measured before and after stretching. Results: The difference in muscle activity and flexibility in the three groups, including cat stretching, seated stretching, and Reclining stretching, all showed statistically significant differences. There was no statistically significant difference in comparison between the three groups of stretch muscle activity. However, a statistically significant difference was shown in the comparison of the variability between the three groups of flexibility. In a post-mortem analysis comparing the amount of change in flexibility, the flexibility of the seated stretching in the chair increased significantly compared to the cat stretching group. Conclusion: It can be confirmed that the stretching method of the erector spinae, cat stretching, seated stretching, and Reclining stretching, all have positive effects on muscle activity and flexibility.

Background: Self-myofascial release using a foam roller has short-term effects for improving muscle function and joint range of motion (ROM) and reducing delayed onset muscle soreness (DOMS) after exercise. Objectives: The purpose of our study was to examine the muscle physiological changes for each set in self-myofascial release of the hamstring muscles using a foam roller in order to provide basic data for the most effective program composition for improving muscle tension, stiffness, and flexibility of the hamstring muscles. Design: A quasi-experimental clinical trial. Methods: To confirm the effect of self-myofascial release of the hamstring muscles using a foam roller, muscle tone and stiffness of the hamstring muscles were measured. As an intervention method, the study subject performed four sessions of self-myofascial release by moving a foam roller back and forth on the posterior thigh muscle of the right leg. Results: There were statistically significant changes in the stiffness of the biceps femoris and the flexibility of the hamstring muscles. Conclusion: Self-myofascial release with foam rolling is an effective intervention method for increasing hamstring flexibility and ROM, and it is recommended as effective to perform self-myofascial release for three to four sessions to maintain normal muscle tone and stiffness of the hamstring muscles.

Purpose: 본 연구의 목적은 4주기간동안 횡격막 호흡을 적용한 기구 필라테스 운동이 20대 성인의 유연성, 복부 근 두께, 근육량, 체지방, 호흡에 미치는 영향에 대해 알아보고자 하는 것이다. Methods: 근골격계 질환이 없는 대상자 35명을 대상으로 수행하였으며, 횡격막 호흡을 하는 그룹과 횡격막 호흡을 하지 않는 그룹으로 나누었으며, 두 그룹 모두 필라테스를 수행하였다. 실험에 사용한 기기로는 Ultrasonography(US), Pulmonary function tests(FEV1 / FVC), Bioeletic Impedance Analysis, Sit and reach test를 사용하였다. 정규성 검증을 실시한 후, 반복측정분산분석 (repeated measures of ANOVA)를 사용하여 운동 전, 호흡을 적용한 운동, 호흡 비적용 운동을 비교하였다. 사후 분석을 위해 Fisher’s LSD를 실시하였다. Results: 필라테스 운동은 복근의 두께와 유연성에 긍정적인 영향을 미쳤습니다. SaR test는 운동 전과 호흡을 적용한 운동과 호흡을 적용하지 않은 운동 사이에 유의한 유의성을 보였다(P <0.05). 근육두께 측정 TRA, EO, IO 모두 운동 전보다 호흡 적용 운동과 비호흡 운동에서 유의한 차이가 있었고(P <0.05), TRA와 IO에서는 추가 시간 사이에 유의한 차이가 없었다. 호흡하지 않는 운동(P >0.05). 그러나 EO에서는 호흡운동을 추가한 시간과 호흡운동을 하지 않은 시간 사이에 유의한 차이가 있었다( P <0.05). Conlusion: 결론적으로, 횡격막 호흡을 이용한 필라테스 운동과 횡격막 호흡이 없는 필라테스 운동은 복근의 두께와 유연성에 긍정적인 영향을 미치는 것으로 나타났다. 그러나 횡격막 호흡과 비횡격막 호흡 사이에는 큰 차이가 없었다.

Background: Although rectus femoris (RF) eccentric training and static stretching (SS) have been reported effectively on lumbar flexibility, and muscle architecture, most studies are results using machines and long-term effects. Therefore, we want to investigate the effect of Reverse Nordic Hamstring Exercise (RNHE), a self-eccentric training, by immediately comparing it with SS. Objectives: To compare the RNHE and SS of RF to show the effects of lumbar flexibility, and fascicle length (FL). Design: Randomized controlled trial. Methods: A total of 30 study subjects were randomly allocated into an experimental group(Reverse Nordic Hamstring Exercise) and a control group(Static Stretching). Before and after the intervention, the subject performed fingertip to floor test (FFT) to evaluate the flexibility of the lumbar spine and measured FL through the SONON 300L (Healcerion Inc., Seoul, South Korea). Results: There was a significant effect on lumbar flexibility within both groups (P<.05), also there were clear results between the two groups (P<.05). FL showed a significant increase in RNHE (P<.05), but not in SS, and there was a no significant difference between the two groups. Conclusion: RNHE is effective in improving lumbar flexibility, and FL of RF muscle.

Background: The gastrocnemius (GCM) is one of the lower extremity muscles that tend to tighten easily. GCM tightness results in limited ankle dorsi-flexion (DF), especially when the knee joint is fully extended. Joint flexibility is determined by the morphological and physiological characteristics of joints, muscles, tendons, and ligaments. Impaired joint flexibility can be attributed to increased susceptibility to muscle injury. High-frequency diathermy is clinically used to reduce pain and muscle tightness and to improve limited range of motion. Objects: This study aimed to investigate the immediate effects of high-frequency therapy in subjects with GCM tightness. Methods: The study was designed as a one-group before–after trial. The subjects included 28 volunteers with GCM tightness (an active ankle DF angle of less than 12°) without any known neurological and musculoskeletal pathologies in the ankle and calf areas. WINBACK Transfer Electrode Capacitive and Resistive Therapy equipment was used to apply high-frequency therapy to the subjects’ GCMs for 10–15 minutes. The pennation angle and the fascicle length of the GCM were measured using ultrasonography. The flexibility of the ankle joint, peak torque to the passive ankle DF (Biodex), and soft tissue stiffness (MyotonPRO) were also measured. Results: The pennation angle was significantly decreased following the treatment; however, no significant difference in the fascicle length was found (p < 0.05). The flexibility was significantly increased and both the passive peak torque to passive ankle DF and the soft tissue stiffness significantly decreased (p < 0.05). Conclusion: High-frequency therapy is immediately effective for improving the muscle’s architectural properties and functional factors in subjects with GCM tightness. Further longitudinal clinical studies are required to investigate the long-term effects of high-frequency therapy on subjects with GCM tightness from various causes.

Background: Effect of cervical and lumbar tractions on the reduction in the angle of curvature and the effect of a correction exercise or a general traction method on balance, muscle strength, pain, and body alignment, however insufficient research has been undertaken on self traction exercises targeting patients with scoliosis. Purpose: To determine the effect of cervical and lumbar tractions on the reduction in the angle of curvature and the effect of a correction exercise or a general traction method on balance, muscle strength, pain, and body alignment. Design: Randomized controlled clinical trial (single blinded) Methods: Twelve adults(20s) with scoliosis were included in this study and performed a traction program that was composed of a 5-min warm-up exercise, a 15-min main exercise, and a 5-min cool-down exercise (25 minutes in total), three times a week for four weeks. The Chiro traction machine was used for the self-traction exercise. Vertebral alignment, muscle strength, and flexibility were compared before and after the intervention using the paired T-test. Results: The scoliosis angle, pelvic torsion, and lumbar extensor were significantly changed by intervention; however, there was no significant difference in flexibility. Conclusion: The results revealed that self-traction exercise activated blood flow through the extension and contraction of muscles, effectively increasing the function of the muscles around the vertebrae.

Background : Several studies have suggested different arguments for the effect of stretching exercises and core muscle exercises on flexibility and balance ability. Objective : To determine the effects of stretching exercises and core muscle exercise on flexibility and balance ability. Design : Quasi experimental research Method : The study applied exercise interventions (three sessions per week for 6 weeks) on 40 subjects. The subjects were divided into stretching and core muscle exerciseing groups to identify the change of flexibility and balance ability. Sit- and- reach test results and hip hyperextension were measured for identifying changes in flexibility, and the Romberg test and Pedalo stabilizer were used for changes in balance ability. Results : Both the stretching exercise and core muscle exercise groups showed a statistically significant increase in flexibility (p<.05). However, the stretching exercise group showed a statistically significant increase in balance ability (p<.05), whereas the core muscle exercise group showed partially statistically significant differences in this par t(p>.05). In the analysis of the differences in the amount of change in flexibility, based on the types of exercise, stretching exercises showed a significant difference (p<.05), whereas a significant difference was not found in the amount of change in balance ability (p>.05). Conclusions : These findings indicate that stretching exercises are the more effective intervention for improving and maintaining flexibility, whereas there is no difference between stretching and core muscle exercises with respect to improving balance ability.

Background: Flexion-relaxation phenomenon (FRP) was a term which refers to a sudden onset of myoelectric silence in the erector spinae muscles of the back during standing full forward flexion. Hamstring muscle length may be related to specific pelvic and trunk movements. Many studies have been done on the FRP of the erector spinae muscles. However, no studies have yet investigated the influence of hamstring muscle flexibility on the FRP of the hamstring muscle and lumbopelvic kinematics during forward bending. Objects: The purpose of this study was to examine the flexion-relaxation ratio (FRR) of the hamstring muscles and lumbopelvic kinematics and compare them during forward bending in subjects with different hamstring muscle flexibility. Methods: The subjects of two different groups were recruited using the active knee extension test. Group 1-consisted of 13 subjects who had a popliteal angle under 30°; Group 2-consisted of 13 subjects who had a popliteal angel above 50°. The kinematic parameters during the trunk bending task were recorded using a motion analysis system and the FRRs of the hamstring muscles were calculated. Differences between the groups were identified with an independent t-test. Results: The subjects with greater hamstring length had significantly less lumbar spine flexion movement and more pelvic flexion movement. The subjects with greater pelvic flexion movement had a higher rate of flexion relaxation during full trunk bending (p<.05). Conclusion: The results of this study suggest that differences in hamstring muscle flexibility might cause changes in people’s hamstring muscle activity and lumbopelvic kinematics.

This study aims to identify the effects of extracorporeal shock wave therapy and stretching technique on flexibility, muscle tone and pressure pain threshold of a shortened hamstring. A total of 40 patients with hamstring shortening was randomly assigned to either the extracorporeal shock wave therapy group (n=20) or extracorporeal shock wave therapy with stretching technique group (n=20) to identify the effects of the two different forms of physical therapy intervention. All the participants underwent extracorporeal shockwave therapy twice a week for 3 weeks, and the extracorporeal shockwave therapy with stretching technique group performed stretching techniques with the same frequency for 3 weeks. To measure hamstring flexibility before and after intervention, the passive straight leg raising test was performed, and muscle tone and pressure pain threshold were assessed. The flexibility of the hamstrings significantly improved, while the pressure pain threshold increased in both groups. These findings suggest that the effective in improving hamstring flexibility, reducing muscle tone, and increasing pressure pain threshold in adults with hamstring shortening.

The objective of this study was to determine the duration of maintained calf muscle flexibility gained in young adults with calf muscle tightness, as measured by increases in ankle active and passive dorsiflexion range of motion (DFROM) after three stretching interventions. Twenty subjects (5 men and 15 women) with calf muscle tightness received the following three stretching interventions in one leg (assigned at random): static stretching (SS), eccentric training on stable surface (ETS), and eccentric training on unstable surfaces (ETU). The subjects received all three interventions to the same leg, applied in a random order. Each intervention had a break of at least 24 h in-between, in order to minimize any carryover effect. Each intervention used two types of stretching: with the calf muscle stretched and both knees straight, and with the knee slightly bent in order to maximize the activation of the soleus muscle. All three interventions were performed for 200 seconds. We measured the duration of maintained calf muscle flexibility through active and passive ankle DFROM before intervention, immediately after intervention (time 0), and then 3, 6, 9, 15, and 30 min after intervention. We found a difference in the duration of maintained calf muscle flexibility between the three interventions. In the ETS and ETU interventions, a significant improvement in calf muscle flexibility, both ankle active and passive dorsiflexion ranges of motion (ADFROM and PDFROM), was maintained for 30 min. In the SS intervention, however, ADFROM before 9 min and PDFROM before 6 min were statistically different from the baseline. Our results suggest that ETS and ETU may be more effective than SS for maintaining calfmuscle flexibility in young adults.