• Journal of Digital Convergence
• /
• v.15 no.2
• /
• pp.411-419
• /
• 2017

This study was to investigate whether a trunk correction taping plus scapular setting exercises has an effect on trunk muscle activation and trunk balance and upper extremity function in patients with stroke. Twenty stroke patients were randomly divided into a trunk correction taping with scapular setting exercise group (n=10) and a scapular setting exercise group (n=10), and each group performed given interventions for 30 minutes for 4 weeks. In the experimental group, there were significant increases in muscle activation, K-TIS, and MFT (p<.05), and a significant improvement was detected in K-TIS and MFT compared to the control group (p<.05). This study suggests that a trunk correction taping with scapular setting exercises was more effective on trunk muscle activation, trunk balance, and upper extremity function in stroke patients compared to a scapular setting exercise. It could be clinically more significant if the change in the onset time of muscle activity is confirmed in the further researches.

• Physical Therapy Korea
• /
• v.26 no.4
• /
• pp.29-34
• /
• 2019

Background: The serratus anterior is one of the most important muscle for maintaining good scapular alignment in the shoulder joint. The pectoralis major and upper trapezius may also compensate for weak serratus anterior muscles. The push-up plus exercise has been identified as the optimal exercise for maximum activation of the serratus anterior. Objects: The purpose of this study was to examine differences in surface electromyography (EMG) activity of upper trapezius, pectoralis major, and serratus anterior muscles during push-up plus exercises on variously angled surfaces in subjects with winged scapula. Methods: Sixteen subjects with winged scapula (male=5, female=11) volunteered for this study. The subjects performed push-up plus exercise on four different tilt angles, namely $0^{\circ}$, $30^{\circ}$, $60^{\circ}$, and $90^{\circ}$. EMG activities in the serratus anterior, upper trapezius, and pectoralis major muscles during performance of push-up plus exercise were measured in all subjects. Data were processed from repeated measures one-way analysis of variance. Results: There was significant difference in the muscle activity of the serratus anterior on the different surface angles (p<.05). The results of the post-hoc analysis showed significantly greater serratus anterior muscle activity on a surface at a $0^{\circ}$ angle than at others tilt angles (p<.05). There was also significant difference in the ratio of serratus anterior to upper trapezius and serratus anterior to pectoralis major across the four surfaces (p<.05), and post-hoc analysis showed significantly greater values on the $0^{\circ}$ surface than on other tilts (p<.05). Conclusion: This study found that performing push-up plus exercises on a flat surface with $0^{\circ}$ and $30^{\circ}$ tilt angle achieves high activation of the serratus anterior muscle for selective strengthening. It can also take into account the sequential application, which is first performed at a $30^{\circ}$ and at a $0^{\circ}$ tilt angle for and effective but not excessive muscle activation.

• Journal of the Korean Society of Physical Medicine
• /
• v.13 no.4
• /
• pp.67-74
• /
• 2018

PURPOSE: This study was conducted to investigate the effects of vibration frequency and amplitude on scapular winging during the knee push-up plus exercise. METHODS: A total of 26 female subjects with scapular winging were evaluated while performing the knee push-up plus exercise with no vibration, low-frequency/low-amplitude (5 Hz/3 mm) vibration, low-frequency/high-amplitude (5 Hz/9 mm) vibration, high-frequency/low-amplitude (15 Hz/3 mm) vibration, and high-frequency/high-amplitude (15 Hz/9 mm) vibration. The surface EMG of the serratus anterior (SA) muscle was compared between the vibration frequency and amplitude. The EMG amplitude was normalized using the maximal voluntary isometric contraction (MVIC). The statistical significance of the results was evaluated using one-way ANOVA. RESULTS: The SA muscle EMG values increased at low-frequency/low-amplitude vibration and at low-frequency/high-amplitude vibration compared to no vibration. Furthermore, the same values increased at high-frequency/low-amplitude vibration and high-frequency/high-amplitude vibration compared to no vibration. In general, a higher vibration frequency and amplitude was associated with higher EMG values of the SA muscle, with particularly greater increases observed during high-frequency/high-amplitude vibration. There was also a significant difference between each condition with a high-frequency/high-amplitude vibration (p<.05). CONCLUSION: This study suggests that there were remarkable clinical effect of the knee push-up plus exercise with vibration, which enhanced the SA muscle activation in persons with scapular winging. Furthermore, applying a higher vibration frequency and amplitude more effectively increased for increasing SA muscle activation.

• Korean Journal of Applied Biomechanics
• /
• v.32 no.1
• /
• pp.31-36
• /
• 2022

Objective: The purpose of this study was to investigate muscle activation according to the four strap lengths in the TRX plank exercise to provide scientific and accurate data on effective training methods. Method: Twenty healthy men who had at least 6 months of weight training experience and could fully adjusted plank exercise, were participate in this study (age: 25.2 ± 3.7 yrs., height: 174.2 ± 3.9 cm., weight: 71.2 ± 9 kg). To pursue the study purpose, surface electrodes were attached to trunk muscles (pectoralis major, rectus abdominis, external oblique, internal oblique, erector spinae, latissimus dorsi) and lower extramity muscles (gluteus maximus, rectus femoris, gastrocnemius), and the muscle activity was measured using 11-channel electromyography equipment. In order to verify the muscle activation according to the four strap lengths during TRX plank exercise, an one-way ANOVA with repeated measure was used with statistical significance level set at as α=.05. Results: First, there were statistically significant differences in pectoralis major, rectus abdominis, external oblique, internal oblique, and erector spinae among TRX strap lengths. Second, there were statistically significant differences in gluteus maximus, rectus femoris, and gastrocnemius among TRX strap lengths. Third, even though no statistically significant difference found in latissimus dorsi, but increased muscle activation tendency was showed as the length of the strap increased. Conclusion: From the results of this study, it may be possible that TRX exercise prevent injuries and improve lower extremity muscle as well as trunk muscles by setting appropriate length of strap.

• Korean Journal of Applied Biomechanics
• /
• v.32 no.4
• /
• pp.128-133
• /
• 2022

Objective: This study was executed to compare and analyze shoulder muscle activation while using an inelastic bar and elastic bar during overhead press exercise. The stability and coordination of shoulder joints will be investigated by measuring and analyzing the EMG of the upper and lower arm muscles. Method: A total of 20 university male students were recruited by dividing into 2 groups; 10 elastic bar participants (age: 20.17 ± 0.41 yrs, height: 174.31 ± 3.34 cm, weight: 74.68 ± 5.65 kg) and 10 inelastic bar participants (age: 20.09 ± 0.23 yrs, height: 173.53 ± 4.11 cm, weight: 75.32 ± 3.31 kg) participated in this study. Results: The EMG analysis results of the four muscles measured in this study showed that there was no difference between the left and right muscles between the groups in Upper Trapezius muscle. In Deltoid, Infraspinatus, and Rectus Abdominis muscles, the elastic bar group was significantly higher than the inelastic bar group between groups, and there was no difference between left and right. Conclusion: Among the four muscles measured in this study, there was no difference between left and right in Deltoid, Infraspinatus, and Rectus Abdominis, but the elastic bar showed significantly higher muscle activity than the inelastic bar. Therefore, it was found that the elastic bar increases muscle activation during exercise than the inelastic bar, and in particular, it further increases muscle activation of the arms and torso, and exercise using the elastic bar can increase neuromuscular stabilization.

• Journal of the Korean Society of Physical Medicine
• /
• v.7 no.2
• /
• pp.199-203
• /
• 2012

Purpose : Bridging exercise was used most frequently of lumbar stabilization exercise. There has been no reserch regarding the bridging exercise according to hip abductor activation or hip adductor activation. The purpose of this study is to determine correlation of hip abductor, adductor and abdominal muscles, lower limb muscle. Methods : Participants who met the criteria for this study (n=45). Participants performs bridging exercise on three types (normal bridging exercise, bridging exercise with hip abductor contraction, bridging exercise with hip adductor contraction) for evaluate correlation of each muscles. Results : There was a significant negative correlation between adductor magnus and gluteus medius, adductor magnus and rectus femoris. And there was a positive correlation between gluteus medius and rectus femoris on normal bridging exercise (p<0.05). There was a significant positive correlation between adductor magnus and gluteus medius, transverse abdominis, and between gulteus medius and transverse abdominis on bridging exercise with adductor magnus activation (p<0.05). There was a significant positive correlation between adductor magnus and gluteus medius, rectus femoris, and between gulteus medius and rectus femoris on bridging exercise with gluteus medius activation (p<0.05). Conclusion : When we perform bridging exercise for transverse abdominis activation and increase pressure in the abdmen, bridging exercise with hip adductor contraction is more effective than normal bridging exercise and bridging exercise with hip abductor contraction.

• Journal of Korean Physical Therapy Science
• /
• v.13 no.3
• /
• pp.15-25
• /
• 2006

The purpose of this study was to investigate effects of different chair type (with backrest chair and without backrest chair) and pelvic position (anterior pelvic tilting and posterior pelvic tilting) on three abdominal muscles (upper rectus abdominis, external oblique, internal oblique) and back extensor activation during lower extremity exercise. The four different conditions during bilateral knee extension exercise were: (1) leaning on backrest chair with anterior pelvic tilting, (2) leaning on backrest chair with posterior pelvic tilting, (3) anterior pelvic tilting without backrest chair, and (4) posterior pelvic tilting without backrest chair. Fifteen healthy male subjects with no history of neuromusculoskeletal disease voluntarily participated in this study. Electromyography (EMG) was used to collect muscle activation data, and muscle activation data was expressed as a percentage of maximal voluntary isometric contraction (%MVIC). One-way repeated analysis of variance (ANOVA) was used to determine the statistical significance, and Bonferroni comparison was used as a post hoc test. The results of this study were the following: (1) Erector spinae activation was significantly lower in posterior pelvic tilting without backrest compared with that in leaning on backrest chair with anterior pelvic tilting. (2) Upper rectus abdominis activation was significantly lower than erector spinae in all four different chair type and pelvic tilting conditions.

• Journal of the Korea Convergence Society
• /
• v.9 no.11
• /
• pp.385-391
• /
• 2018

The purpose of this study was to examine the lower-extremity muscle activation of flat-footed and normal-footed subjects descending stairs while wearing high-heels, thereby identifying any imbalance between the medial and lateral muscles.Thirty female students volunteered to participate in this study. The navicular drop test (NDT) was applied to the selection criteria for the flat-footed group and the normal-footed group. Surface electromyographic data was collected from the medial and lateral quadriceps, hamstrings, and gastrocnemius. Activation of MG and LG was significantly lower in the flat-footed group than in the normal-footed group. Both groups showed significant increases in MQMH and MHMG, but the co-activation in the medial and lateral muscles was lower in the flat-footed group. The co-activation ratios showed a significantly greater MQMH/LQLH in the flat-footed group. Flat-footed subjects who wear high-heels are more likely to experience impaired knee joint alignment than normal-footed subjects. Therefore, flat-footed subjects should use caution when descending stairs while wearing high-heels.

• PNF and Movement
• /
• v.13 no.2
• /
• pp.81-88
• /
• 2015

Purpose: The purpose of this study was to analyze the effect of normal timing according to angular motion in PNF patterns on electromyography (EMG) activity in rectus abdominis, internal oblique abdominal muscle, external oblique abdominal muscle, and erector spinae. Methods: Ten healthy adults volunteered to participate in this study. The participants were required to complete following two PNF extremity patterns; upper extremity extension- adduction-internal rotation pattern with $180^{\circ}$, $90^{\circ}$, $30^{\circ}$ and lower extremity flexion- adduction-external rotation pattern with $0^{\circ}$, $60^{\circ}$, $90^{\circ}$. A paired t-test was used to determine the influence of the two PNF patterns on muscle activity in each muscle. Descriptive statistics were used to determine the ratio of local muscle activity to global muscle activity. Results: In terms of their effect on applied normal timing, the upper and lower extremity pattern significantly affected the rectus abdominis, internal oblique, external oblique, and erector spinae (p < .05). The upper extremity pattern (at an extension angle of $30^{\circ}$) and the lower extremity pattern ((at a flexion angle of $90^{\circ}$) influenced the rectus abdominis, internal oblique, external oblique, and erector spinae (p < .05). Conclusion: The effect of the upper and lower extremity patterns on applied normal timing was significant in that these patterns increased trunk muscle activation. The upper extremity pattern (at an extension angle of $30^{\circ}$) and the lower extremity pattern (at a flexion angle of $90^{\circ}$) increased trunk muscle activation. Normal timing is required to increase trunk muscle strength and extremity movement.

• The Korean Journal of Physiology and Pharmacology
• /
• v.5 no.4
• /
• pp.287-297
• /
• 2001

Contraction of smooth muscle is initiated by an increase in cytosolic $Ca^{2+}$ leading to activation of $Ca^{2+}$/ calmodulin-dependnet myosin light chain (MLC) kinase and phosphorylation of MLC. The types of contraction and signaling mechanisms mediating contraction differ depending on the region. The involvement of these different mechanisms varies depending on the source of $Ca^{2+}$ and the kinetic of $Ca^{2+}$ mobilization. $Ca^{2+}$ mobilizing agonists stimulate different phospholipases $(PLC-{\beta},\;PLD\;and\;PLA_2)$ to generate one or more $Ca^{2+}$ mobilizing messengers $(IP_3\;and\;AA),$ and diacylglycerol (DAG), an activator of protein kinase C (PKC). The relative contributions of $PLC-{\beta},\;PLA_2$ and PLD to generate second messengers vary greatly between cells and types of contraction. In smooth muscle cell derived form the circular muscle layer of the intestine, preferential hydrolysis of $PIP_2$ and generation of $IP_3$ and $IP_3-dependent\;Ca^{2+}$ release initiate the contraction. In smooth muscle cells derived from longitudinal muscle layer of the intestine, preferential hydrolysis of PC by PLA2, generation of AA and AA-mediated $Ca^{2+}$ influx, cADP ribose formation and $Ca^{2+}-induced\;Ca^{2+}$ release initiate the contraction. Sustained contraction, however, in both cell types is mediated by $Ca^{2+}-independent$ mechanism involving activation of $PKC-{\varepsilon}$ by DAG derived form PLD. A functional linkage between $G_{13},$ RhoA, ROCK, $PKC-{\varepsilon},$ CPI-17 and MLC phosphorylation in sustained contraction has been implicated. Contraction of normal esophageal circular muscle (ESO) in response to acetylcholine (ACh) is linked to $M_2$ muscarinic receptors activating at least three intracellular phospholipases, i.e. phosphatidylcholine-specific phospholipase C (PC-PLC), phospholipase D (PLD) and the high molecular weight (85 kDa) cytosolic phospholipase $A_2\;(cPLA_2)$ to induce phosphatidylcholine (PC) metabolism, production of diacylglycerol (DAG) and arachidonic acid (AA), resulting in activation of a protein kinase C (PKC)-dependent pathway. In contrast, lower esophageal sphincter (LES) contraction induced by maximally effective doses of ACh is mediated by muscarinic $M_3$ receptors, linked to pertussis toxin-insensitive GTP-binding proteins of the $G_{q/11}$ type. They activate phospholipase C, which hydrolyzes phosphatidylinositol bisphosphate $(PIP_2),$ producing inositol 1, 4, 5-trisphosphate $(IP_3)$ and DAG. $IP_3$ causes release of intracellular $Ca^{2+}$ and formation of a $Ca^{2+}$-calmodulin complex, resulting in activation of myosin light chain kinase and contraction through a calmodulin-dependent pathway.