• Physical Therapy Korea
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• v.15 no.2
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• pp.11-19
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• 2008

Studies of attentional focus effects, have shown that the performer's attentional focus plays an important role in the performance and learning of motor tasks. We examined the influence of attentional focus on the performance of dual tasks (a postural task and a suprapostural task) and used electromyography (EMG) to examine whether the differences between external and internal focus were also manifest at the neuromuscular level. The subjects (n=40) stood on a balance board (postural task) and held a bar horizontally (suprapostural task). All of the subjects performed under different attentional focus conditions: external (balancer on balance board) or internal (feet) focus on the postural task, and external (balancer on bar) or internal (hand) focus on the suprapostural task. The mean displacement velocity of the bar and the percent reference voluntary contraction (%RVC) of the biceps brachii were reduced when the subjects adopted an external focus on the suprapostural task (p<.05). In addition, the mean displacement velocity of the balance board and %RVC of the tibialis anterior were reduced when the subjects adopted an external focus on the postural task (p<.05). When the subjects adopted an external focus on the suprapostural task, the mean displacement velocity of the balance board and %RVC of the tibialis anterior were also reduced (p<.05). When the subjects' attentional focus was on the postural task, there were no differences in the mean displacement and %RVC of the biceps brachii between attentional focuses. The performance of each task was enhanced when subjects focused on the respective task. The suprapostural task goals had a stronger influence on postural control than vice versa. These results reflect the propensity of the motor system to optimize control processes based on the environmental outcome, or movement effect, that the performer wants to achieve.

• Korean Journal of Applied Biomechanics
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• v.21 no.4
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• pp.467-477
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• 2011

This study was performed to investigate the effects of tibial rotation while going up stair on muscle activity of vastus medialis oblique and vastus lateralis, and on patellar displacement. The subjects included 30 people (male: 15; female: 15) who were randomly assigned to the tibial internal-rotation, neutral-rotation, and external-rotation groups. The subjects went up the stair while performing the assigned rotations, and the rotation of the hip and the displacement of the patella were measured using a 3D motion analyzer. In addition, the maximum voluntary isometric contraction (MVIC) of the vastus medialis oblique and vastus lateralis were measured using surface electromyogram. On the tibial internal rotation, the hip rotation significantly appeared in the same direction and so did on the tibial neutral and external rotations(p<.001). Although the MVIC of the vastus medialis oblique and vastus lateralis did not significantly differ by tibial rotation during the stair ascent, the MVIC of the vastus medialis oblique was higher than that of the vastus lateralis during the internal and neutral rotations (p<.05). In addition, during the stair ascent, the displacement of the patella was more significant during the tibial external rotation than during the tibial internal and neutral rotations(p<.001). Thus, patients with patellofemoral pain are required to be considered the effects of tibial rotation for their rehabilitation.

• The Journal of Korean Physical Therapy
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• v.32 no.3
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• pp.157-162
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• 2020

Purpose: This study was to evaluate several tasks performed at a high intensity in terms of their ability to elicit EMG activity in the serratus anterior by comparing the EMG activities of the serratus anterior, upper trapezius, and lower trapezius muscles during six tasks combined shoulder flexion with rotation. Methods: Fifteen healthy males were recruited to this study. Each subject was instructed to assume a sitting position without back support and asked to flex (90° or 120°) the right shoulder and protract the scapula in the sagittal plane with maximal external rotation; to assume a neutral position; or to internally rotate the glenohumeral joint. The EMG data were collected from the serratus anterior (SA), upper trapezius (UT), and lower trapezius (LT) muscles were normalized to maximum voluntary isometric contraction. The UT/LT and UT/SA muscle activity ratios in each task were assessed by calculating the surface EMG. Data were analyzed by two-way repeated-measures analysis of variance, with the level of significance set at p<0.05. Results: The results of this study, shoulder flexion with external rotation resulted in low upper trapezius/serratus anterior and upper trapezius/lower trapezius ratios and a relatively high level of serratus anterior activation. Conclusion: Shoulder flexion with external rotation used herein may be considered as important for clinical interventions aimed at selectively increasing SA strengthen and clinical selection of exercises for improving glenohumeral joint and scapulothoracic control.

• Journal of Korean Medical classics
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• v.26 no.2
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• pp.133-174
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• 2013

Objective : Malaria(瘧疾) is a disease that's main symptom is paroxysm - a cyclical occurrence of sudden coldness followed by rigor and then fever. Since the introduction of the cause and mechanism of malaria(瘧疾) in the "Suwen(素問)", including Cold malaria(寒瘧), Warm malaria(溫瘧), Heat malaria(癉瘧) and Wind malaria(風瘧), there has been over 20 different kinds of malaria, each of which are introduced in multiple medical texts. Method : Through comparison between "Suwen(素問)" and other medical texts, the categories, causes and mechanisms of malaria can be analysed and organized to overview the whole feature of it. Results & Conclusion : External pathogens of malaria(瘧疾) are wind(風), cold(寒), summerheat (暑), dampness(濕), miasmic toxin(瘴), pestilence(疫), ghost(鬼). Internal pathogens of malaria(瘧疾) are dietary irregularities(飮食不節), overexertion and fatigue(勞倦), phlegm(痰), seven emotion(七情). Malaria can be categorized into four groups according to the pathological mechanism that leads to paroxysm. They are latency of disease(伏氣), external contraction(外感), internal damage(內傷), and combination of disease(合病). Malaria-Paroxysm(瘧疾發作) occurs when the three following factors collide strongly : defense qi(衛氣), latent qi(伏邪) and external pathogen(新邪). When collision of the three factors takes place in the interior(裏), the body experiences chills. When it takes place in the exterior(表), the body experiences fever. The cyclical occurrence of Malaria-Paroxysm follows the circulation of defense qi.

• Physical Therapy Rehabilitation Science
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• v.4 no.2
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• pp.108-114
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• 2015

Objective: The purpose of this study was to examine the effect on vital capacity (VC) and inspiratory muscle activation according to the anterior and posterior pelvic tilt positions. Design: One group pretest-posttest design. Methods: Twenty-six healthy adult men and women, age 19 to 27 years, volunteered to participate in this study. Forced vital capacity (FVC), and forced expiratory volume in 1 second ($FEV_1$) were measured by desktop spirometer in the pelvic positions during respiration, and muscle activation was recorded from sternocleidomastoid, upper trapezius, external intercostal, rectus abdominis, and external oblique muscles by surface electromyography (EMG) at the same time. EMG values were normalized by maximum muscle contractions (% maximum voluntary isometric contraction). Subjects were to breathe in as much air as possible and then exhale as quickly as possible in both anterior and posterior pelvic tilt positions. To measure lung capacity, inspiration was measured for 5 seconds and expiration was measured for 7 seconds with data collection taken place during the middle three seconds. Lung capacities were measured in each position three times. Results: For the results of this study, there was a significant increase in both FVC and $FEV_1$ values during the anterior pelvic tilting compared to the posterior pelvic tilting posture (p<0.05). The sternocleidomastoid, upper trapezius muscle, rectus abdominus and external oblique muscle activation was significantly increased during anterior pelvic tilt compared to the posterior pelvic tilt position (p<0.05). Conclusions: These findings suggest that pelvic anterior tilt position could be more effective for vital capacity and respiratory muscles activation during respiration.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.63-73
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• 2015

The purpose of this study was to examine EMG activities and VMO/VL ratio of the vastus medialis oblique, and vastus lateralis during step up exercise according to ankle and knee positions in soccer players with patellofemoral pain syndrome. Methods: Subject(patellofemoral pain syndrome, PFPS: n=8 and without PFPS, non PFPS; NPFPS: n=8) perfomed step up exercise at each knee and ankle position(knee flexion $30^{\circ}$, $60^{\circ}$, and $90^{\circ}$, ankle internal rotation $30^{\circ}$, neutral, and external rotation $30^{\circ}$) while EMG activity was collected. The EMG signals were expressed by the % maximal voluntary isometric Contraction(%MVIC) values. Statistical analysis consisted of two way repeated measures analysis of variance with post hoc analysis. Results: Main results were as follows: 1) EMG of VMO, and VL was tend to be lower in PFPS compared to NPFPS. 2) EMG of VMO and VL with knee flexrion $60^{\circ}$ was significantly higher the results with knee flexion $30^{\circ}$, and $90^{\circ}$. VMO and VL with ankle external rotation $30^{\circ}$ was significantly higher the results with internal rotation $30^{\circ}$ and neutral position. Conclusion: Considering the EMG activity was reduced due to the to the PFPS and that performing step up with knee flexion $60^{\circ}$ with ankle external rotation $30^{\circ}$ position may provide the most effective condition for patients with patellofemoral pain syndrome.

• Physical Therapy Korea
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• v.16 no.1
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• pp.18-24
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• 2009

The purpose of this study was to assess the effect of bridging stabilization exercises on trunk muscles activity on and off a Swiss ball. 20 healthy university students volunteered to participate in this study. Subjects were required to complete following four exercises: exercise 1, single bridging exercise; exercise 2, feet on ball bridging exercise; exercise 3, calf on ball bridging exercise; exercise 4, back on ball bridging exercise. Surface electromyography from selected trunk muscles was normalized to maximum voluntary isometric contraction. A repeated measures of ANOVA with post-hoc Bonferroni's correction was used to determine the influence of exercise type on muscle activity for each muscle and descriptive statistics was used to determine local/global muscle ratios. The rectus abdominis of exercise 4 showed significantly higher muscle activity than rectus abdominis of exercise 1, 2, 3 (p<.05). The external oblique of exercise 2, 4 showed significantly higher muscle activity than external oblique of exercise 1 (p<.05). The internal oblique of exercise 2, 4 showed significantly higher muscle activity than internal oblique of exercise 1 (p<.05). The erector spinae of exercise 2, 3, 4 showed significantly higher muscle activity than erector spinae of exercise 1 (p<.05). Median of internal oblique/rectus abdominis ratio of exercise 1 was 1.16, exercise 2 was 2.43, exercise 3 was 2.45, exercise and 4 was 1.27. Median of internal oblique/external oblique ratio of exercise 1 was 1.01, exercise 2 was .91, exercise 3 was .99, and exercise 4 was .93. Muscle activity can be influenced by addition of a Swiss ball in bridging exercises. It is recommend to use a Swiss ball for trunk stabilization exercise.

• PNF and Movement
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• v.18 no.1
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• pp.35-44
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• 2020

Purpose: The purpose of this study was to investigate the effect of the simultaneous abdominal drawing-in maneuver (ADIM) on the muscle activity of the ipsilateral trunk and leg during proprioceptive neuromuscular facilitation (PNF) leg flexion, adduction, and external rotation with knee flexion (D1) patterns. Methods: The participants were 20 healthy adult males and females (18 males and 2 females). The maneuvers were performed by a physical therapist who fully understands the PNF leg patterns (D1) and their application in clinical practice. The participants were trained and allowed to practice for 15 minutes prior to applying ADIM, to ensure adequate learning as evidenced by the pressure biofeedback unit. In this study, we measured the muscle activity of the trunk and leg when the PNF leg pattern (D1) was performed by the physical therapist either sustaining or releasing the ADIM. Muscle activity was measured on the right transverse abdominis muscle (TRA), the external abdominal oblique muscle (EO), the internal abdominal oblique muscle (IO), the erector spinae muscle (ES), the vastus medialis oblique muscle (VMO), the vastus lateralis oblique muscle (VLO), and the tibialis anterior muscle (TA) and compared using the mean values from averaging three repeated measurements. Results: The muscle activity of the transversus abdominis, the external abdominal oblique, the internal abdominal oblique, the vastus medialis oblique, and the vastus lateralis oblique was significantly greater (p < 0.05), and the muscle activity of the erector spinae was significantly less (p < 0.05) during PNF leg pattern (D1) when the ADIM contraction was sustained compared to when it was not. Conclusion: These results suggest that sustaining ADIM during PNF leg pattern (D1) training increases the trunk and leg muscle activity, resulting in more effective training.

• Physical Therapy Rehabilitation Science
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• v.13 no.1
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• pp.78-85
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• 2024

Objective: This Study aimed to examine the changes in muscle activity of trunk muscles by performing three squat exercises on normal adults. Design: cross-sectional study Methods: Thirty-two adult subjects participated in this study. General squat, overhead squat, and overhead squat combined with abdominal stabilization were randomly performed for 5 seconds, 3 times, to calculate the average muscle activation. Muscle activation was normalized using electrodes on the rectus abdominis, external oblique, internal oblique, and erector spinae muscles to measure maximum voluntary isometric contraction (MVIC) for 5 seconds, repeated 3 times each. Results: There was a significant difference in the mean and maximal muscle activity of the bilateral erector spinae (ES) when comparing the squat to the overhead squat (p<0.05). There was a significant difference (p<0.05) in the mean and maximal muscle activity of the bilateral external oblique (EO) when comparing the overhead squat to the overhead squat combined with the abdominal stabilization technique. When comparing the squat to the overhead squat with abdominal stabilization, there was a significant difference in the mean and maximum muscle activity of the bilateral RA, EO, and left Internal oblique (IO) (p<0.05), and there was a significant difference in the maximum muscle activity of the bilateral erector spinae (ES) (p<0.05). Post hoc tests showed significant differences between squatting methods for the RA, EO, IO, and ES (p<0.017). Conclusion: The results of this study showed that squats combined with abdominal stabilization were more effective at activating core muscles than squats or overhead squats alone.

• PNF and Movement
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• v.16 no.2
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• pp.301-306
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• 2018

Purpose: This study aimed to describe and identify the relationship between gait and contracted ratios of the transverse abdominal (TrA), internal oblique (IO), and external oblique (EO) muscles. Methods: This study was conducted on 50 elderly people. The contracted ratios of the lateral abdominal muscles (LAM) were measured using the abdominal drawing-in maneuver (ADIM) and ultrasonographic imaging. Gait was measured using the timed up and go test and the 10 m walk test. Results: The contracted ratios of the TrA and IO muscles significantly increased after ADIM. Those of the TrA muscles showed a significant correlation with gait in the limited community ambulatory group. The contracted ratios of the IO and EO muscles showed a significant correlation with gait in the community ambulatory group. Conclusion: Our findings suggest a specific training on the relationship between gait speed and the activation of the LAM in elderly people.