• Physical Therapy Korea
• /
• v.10 no.2
• /
• pp.11-22
• /
• 2003

The purpose of this study was to analyze the effects of three different pelvic tilts on a sit-to-stand (STS) and to suggest a new assessment approach based on biomechanical analysis. The three difrent pelvic tilts were: (1) comfortable pelvic tilt sit-to-stand (CPT STS), (2) posterior pelvic tilt sit-to-stand (PPT STS) and (3) anterior pelvic tilt sit-to-stand (APT STS). To determine the onset time of muscle contraction surface electrodes were applied to the rectus femoris muscle (RF), vastus lateralis muscle (VL), biceps femoris muscle (BF), tibialis anterior muscle (TA), gastrocnemius muscle (GCM), and soleus muscle (SOL). The ICC was used for functional linkage analysis. The findings of this study were as follows. First, significant differences were found in kinematic variables and in muscle activation pattern among the three activities. Second, the results of functional integrated analysis revealed that recruited muscle activation patterns changed when the thigh-off was viewed as a reference point. Third, there were independent functional units between the thigh-off and the VL and between the thigh-off and the RF in the functional linkage analysis. The VL and RF acted as prime mover muscles, and more postural adjustment muscle recruitment was required as the demand of postural muscle control increased (PPT STS, APT STS, and CPT STS in order). In conclusion, the findings of this study suggest the following evaluative and therapeutic approach for STS activity. APT STS can be introduced for movement efficiency and functional advantage when abnormal STS is treated. However, excessive APT would change the muscle activation patterns of BF and SOL and require additional postural muscle control to cause abnormal control patterns.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.29 no.1
• /
• pp.41-52
• /
• 2023

Background: Bulgarian split squat (BSS) is beneficial to improve dynamic balance ability and muscle activity of lower extremities, however its effects have not been fully investigated. Therefore, this study aimed to compare changes in dynamic balance ability and muscle properties according to various modifications of BSS exercises. Methods: Thirty healthy male volunteers participated in this study, and they were randomly divided into three different groups. The subjects performed the BSS exercise either on a stable surface with the eyes opened (n=10) or eyes closed (n=10), and on an unstable support plane with eyes opened (n=10) conditions, respectively. Dynamic balance ability was measured via Biodex balance system under the eyes-opened and closed conditions. Additionally, muscle properties of the rectus femoris (RF), vastus medialis (VM) and vastus lateralis (VL) were evaluated. Results: Dynamic balance ability did not show the significant differences among the groups that performed the BSS exercises. However, in the Unstable group, there were significant differences in the overall stability index and anterior posterior stability index under the eyes-closed condition between pre-exercise and post-exercise. In comparison of muscle properties according to the groups, RF muscle showed a significant difference in amount of change of elasticity (p=.038). Additionally, there were significant changes in post measurements of VM muscle tone (p=.016), stiffness (p=.012) and elasticity (p=.002). VL muscle, however had no significant differences in muscle properties. Conclusion: These results indicate that BSS exercises could induce the alteration of RF and VM muscle properties, in particular VM muscle which is susceptible to weakness. Thus, BSS could be applied in various ways as an effective rehabilitation exercise.

• Journal of Acupuncture Research
• /
• v.22 no.5
• /
• pp.29-36
• /
• 2005

Objectives : This study is performed to understand the interrelation between 'Foot soyang muscle of the Gall bladder channel' and 'muscular system' on the basis of the link between meridian muscle theory and myofascial pain syndrome. Methods : We have researched some of oriental medical books about meridian muscle theory and western medical books about anatomical muscular system. Results & Conclusion : 1. Myofascial pain syndrome is the medical treatment which finds the start point of the pain in fascia and then treats it on the basis of object and concrete anatomical theory, so its application is needed for objectification of the oriental medicine. 2. There is a wide difference between myofascial pain syndrome and meridian muscle theory in that the former explains each muscle individually, while the latter classifies muscles systematically in the view of organism. 3. Foot soyang muscle contains Dorsal interosseous m, Extensor digitorum longus m, Musculus peroneus brevis, longus and, tertius, lliotibial tract, Vastus lateralis m, Gluteus m, Aximus m, Piriformis m, Tensor fasciae latae m, Gluteus minimus m, Obliquus internus & externus abdominis m, External & Internal intercostal m, Serratus anterior m, Pectoralis major m, Sternocleidomastoid m, Auricularis posterior m, Temporalis m, Masseter m, Orbicularis oculi m etc. on the basis of function and the nature of a disease reflected in muscle. 4. Foot soyang muscle keeps the balance of left md right of the body on the outside, while the Gall bladder keeps the balance of the JangBuKiHyeul(臟腑氣血) on the inside.

• Physical Therapy Rehabilitation Science
• /
• v.7 no.4
• /
• pp.154-163
• /
• 2018

Objective: The purpose of this study was to investigate the effects of eccentric contraction training (ECT) and concentric contraction training (CCT) on the muscle thickness (MT), muscle strength (MS) and delayed onset of muscle soreness (DOMS) of the lower extremities in persons with chronic stroke. Design: Randomized controlled trial. Methods: Thirty persons with chronic stroke were randomly assigned to the ECT or the CCT group. The ECT was performed in a specially designed system of eccentric contraction of both legs and, the CCT was performed using a traditional stepper system for concentric contraction of both legs. The training was performed for 30 min/times, 3 times/wk for 6 weeks. Rehabilitation ultrasound imaging was used to measure MT of the vastus medialis/lateralis (VL), and soleus (SOL), a digital muscle tester was used to measure MS, and a visual analog scale was used to assess DOMS. Results: In the ECT group, MT was significantly improved except for SOL resting (p<0.01). In the CCT group, the MT was significantly improved except for VL contraction (p<0.05). The MS was significantly improved in both groups, especially in the ECT group (p<0.01). In the ECT group, muscle soreness was highest in the first week after training but gradually decreased, and in the CCT group, it was highest in the second week of training but gradually decreased (p<0.01). Conclusions: ECT can improve lower limb MT, MS, and DOMS of chronic stroke survivors. Therefore, it is recommended that ECT be used in the rehabilitation of persons with chronic stroke.

• Journal of the Korean Society of Physical Medicine
• /
• v.10 no.4
• /
• pp.107-112
• /
• 2015

PURPOSE: This study investigated the effects of lower limb and trunk muscles activation on seat angle and height during sit to stand and stand to sit. METHODS: Subjects were instructed to sit and stand on different angles and heights; $0^{\circ}$(43cm), $5^{\circ}$(48cm), $10^{\circ}$(51cm) and $15^{\circ}$(58cm). Measurements were conducted from sit to stand and stand to sit for external oblique, transversus abdominis, rectus femoris, vastus medialis, vastus lateralis, tibialis anterior and gastrocnemius muscle activation by surface EMG. The muscle activation was measured three times for five seconds in each posture, and the %RVC value was calculated after the exclusion of one second before and after this measurement. This calculation standardized the data from each participant so it could be comparatively analyzed. RESULTS: The external oblique, tibialis anterior, and erector spinae muscles showed significant difference in $10^{\circ}$(51cm), $15^{\circ}$(58cm) and $0^{\circ}$(43cm), rectus femoris, in $15^{\circ}$(58cm) and $0^{\circ}$(43cm)(p<.05) during sit to stand. The external oblique, tibialis anterior, and rectus femoris muscles showed significant difference in $0^{\circ}$(43cm) and $15^{\circ}$(58cm), erector spinae and vastus medialis muscles showed significant difference in $10^{\circ}$(51cm), $15^{\circ}$(58cm) and $0^{\circ}$(43cm)(P<.05) during stand to sit. CONCLUSION: The present study findings indicate that the toilet seat angle and height could affect muscle activities of the lower limb and trunk.

• Journal of the Korean Academy of Clinical Electrophysiology
• /
• v.3 no.1
• /
• pp.49-59
• /
• 2005

This study assigns each 8 of 24 normal persons to control group(Group I), strength increase group(Group II) and endurance increase group(Group III) to analyze differences in changes of strength and endurance with surface electromyography and kinetics according to application modes of neuromuscular electrical stimulation(NMES). Group I had not any treatment, group II performed 15 repeated contraction with 60% intensity of maximal voluntary isometric contraction(MVIC) by setting 10-sec on time and 50-sec off time and group III conducted 30 repeated contraction with 30% intensity of MVIC by setting 10-sec on time and 20-sec off time. For neuromuscular electrical stimulation, 2,500 Hz of Russian current, 35 pps of pulse rate and 200 of pulse width. Neuromuscular electrical stimulation was conducted by five times for total 4 weeks. Before and after experimentmotor unit action potential of vastus medialis, rectus femoris and vastus lateralis were measured with sEMG, median frequency(MDF) was analyzed, and thus the following results were obtained. There was significant difference in the period of measuring vastus medialis and rectus femoris in change of MDF and interaction among groups with analysis of surface electromyography before and after neuromuscular electrical stimulation(p<.001) and in particular, there was a remarkable change among groups according to the period of measurement. In conclusion, NMES influenced changes of strength and endurance according to its application modes and in particular, it was found that strength increment application had a significant influence on strength increment in applying short-time NMES.

• Physical Therapy Korea
• /
• v.10 no.2
• /
• pp.99-110
• /
• 2003

The purpose of this study was to analyze the effects of three different pelvic tilts on sit-to-stand ativities and to suggest a new therapeutic approach for movement reeducation in patients who have difficulty with sit-to-stand activities. The three different pelvic tilts were: (1) comfortable pelvic tilt sit-to-stand (CPT STS), (2) posterior pelvic tilt sit-to-stand (PPT STS) and (3) anterior pelvic tilt sit-to-stand (APT STS). To analyze the kinematic component of STS, a motion analysis system (Zebris) was applied to the ankle, knee, hip joint, and thigh-off area. Also, to determine the onset time of muscle contraction, surface electrodes were placed to the rectus femoris muscle (RF), the vastus lateralis muscle (VL), the biceps femoris muscle (BF), the tibialis anterior muscle (TA), the gastrocnemius muscle (GCM), and the soleus muscle (SOL). One-way repeated ANOVA was used for the statistical analysis. First, significant differences were found in kinematic variables for the hip, knee, ankle joint, and thigh-off among the three activities. Second, there was significant difference in muscle activation pattern in TA. VL. and BF among three activities. In conclusion, the findings of this study suggest the following evaluative and therapeutic approach for STS activity: (1) Changes in knee and ankle joints should be prioritized and recruitment order differences in VL and RF can be generated to accomplish abnormal STS activity. (2) APT STS can be introduced for movement efficiency and functional advantage when abnormal STS is treated.

• The Journal of Korean Physical Therapy
• /
• v.23 no.4
• /
• pp.37-44
• /
• 2011

Purpose: The aim of this study was to investigate the effects of an exercise program using a virtual reality game and a gait exercise program using a treadmill on % maximum voluntary isometric contraction (%MVIC) and static and dynamic balancing capabilities. Methods: A total of 26 elderly women were included in the study. 13 women were assigned to an exercise program using a virtual reality game, and 13 to a gait exercise program using a treadmill. The subjects performed the exercise for 40 min per session, three sessions per week, for eight weeks. Results: The %MVIC of the vastus medialis was significantly increased from $28.91{\pm}2.03%$ to $32.98{\pm}2.6%$ in the virtual reality game exercise group (p<0.00). The %MVIC of the vastus lateralis was significantly increased from $27.17{\pm}1.93%$ to $31.50{\pm}2.18%$ (p<0.00) in the gait exercise program group. The whole path length with both feet on the floor and eyes open was significantly decreased from $1570.92{\pm}820.6mm$ to $1343.62{\pm}242.41mm$ (p<0.00). The whole path length with both feet on the floor and eyes closed was significantly decreased from $1819.85{\pm}361.14mm$ to $1581.05{\pm}285.11mm$ (p<0.00). The length of a functional reach was significantly increased from $25.2{\pm}4.23cm$ to $27.68{\pm}4.04cm$ (p<0.00). Conclusion: The exercise program using a virtual reality game is effective for improving the %MVIC and static and dynamic balancing capabilities in elderly women aged 65 years and more.

• PNF and Movement
• /
• v.19 no.1
• /
• pp.79-86
• /
• 2021

Purpose: The purpose of this study was to investigate muscle activity according to knee flexion angle during single-limb-deadlift exercises. Methods: In total, 26 healthy volunteers participated. The single-limb-deadlift consisted of 0˚, 15˚, and 30˚ knee joint bending. The electromyography data were collected from the semitendinosus (SM), the biceps femoris (BF), the rectus femoris (RF), the vastus lateralis (VL), and the vastus medialis (VM). In addition, hamstrings and quadriceps (HQ) ratio was measured during the single-limb-deadlift using electromyography. Results: During the single-limb-deadlift, RF, VL, and VM were significantly higher at 30˚ bending angles compared to muscle activity of 0˚ and 15˚ knee-joint bending. The HQ ratio had significant differences in all three knee joint bending angles. In particular, the single-limb-deadlift carried out to a 30˚ knee-joint bend showed the closest value to 1. Conclusion: The most balanced coactivation ratios were observed during a single-limb-deadlift to a 30˚ knee-joint bend angle. A single-limb-deadlift at a knee-bend angle of less than 30˚ could be used as an exercise to prevent ACL injury. It could also be used for post-injury rehabilitation programs by increasing knee-joint stability.

• Journal of the Korean Society of Radiology
• /
• v.82 no.6
• /
• pp.1556-1564
• /
• 2021

Purpose This study aimed to apply MR elastography (MRE) to achieve in vivo evaluation of the elastic properties of thigh muscles and validate the feasibility of quantifying the elasticity of normal thigh muscles using MRE. Materials and Methods This prospective study included 10 volunteer subjects [mean age, 32.5 years, (range, 23-45 years)] who reported normal activities of daily living and underwent both T2-weighted axial images and MRE of thigh muscles on the same day. A sequence with a motion-encoding gradient was used in the MRE to map the propagating shear waves in the muscle. Elastic properties were quantified as the shear modulus of the following four thigh muscles at rest; the vastus medialis, vastus lateralis, adductor magnus, and biceps femoris. Results The mean shear modulus was 0.98 ± 0.32 kPa and 1.00 ± 0.33 kPa for the vastus medialis, 1.10 ± 0.46 kPa and 1.07 ± 0.43 kPa for the vastus lateralis, 0.91 ± 0.41 kPa and 0.93 ± 0.47 kPa for the adductor magnus, and 0.99 ± 0.37 kPa and 0.94 ± 0.32 kPa for the biceps femoris, with reader 1 and 2, respectively. No significant difference was observed in the shear modulus based on sex (p < 0.05). Aging consistently showed a statistically significant negative correlation (p < 0.05) with the shear modulus of the thigh muscles, except for the vastus medialis (p = 0.194 for reader 1 and p = 0.355 for reader 2). Conclusion MRE is a quantitative technique used to measure the elastic properties of individual muscles with excellent inter-observer agreement. Age was consistently significantly negatively correlated with the shear stiffness of muscles, except for the vastus medialis.