In dancers, intact muscular coordination is a well balanced antagonist, which could be a decisive factor in protection against injury as dancers often have hypermobile joints and their ankle joints often bear their full body weight in extreme positions. The purposes of this study were to identify the isokinetic strength to the knee and ankle and the isometric strength of the trunk in female collegiate dancers and controls. Furthermore, the study aimed to investigate the peak torque ratio of knee extension to flexion, ankle plantarflexion (PF) to dorsiflexion (DF), and dominant legs to nondominant. Twenty-one female collegiate dancers (20.0 years of age) and twenty-one female collegiate students (19.3 years of age) performed isokinetic maximum efforts of the knee extensors and flexors at and , the ankle plantarflexors and dorsiflexors at and and isometric maximum efforts of the lumbar extensors at 0˚, 12˚, 24˚, 36˚, 48˚, 60˚, and 72˚. The results were as follows: The isokinetic peak torque of the knee extensors and the ratio of knee extensors to flexors of dancers were significantly higher than those of controls (p<.01). However, the isometric peak torque of the back extensors (p<.01) and isokinetic peak torque of the ankle plantarflexors and dorsiflexors (p<.05) of dancers were significantly lower than those of controls. Further studies are needed to identify the difference in proprioception of the joints between dancers and controls.

The aim of this study was to investigate the effect of abdominal drawing-in maneuver (ADIM) on peak exploratory flow (PEF), forced exploratory volume in 1 second (FEV1), and low back pain during forced expiration. Twenty-two subjects (14 subjects in experimental group, 8 subjects in control group) participated in this study. The stabilizer was used for ADIM training for five consecutive days. Vitalograph PEF/FEV1 DIARY and visual analogue scale (VAS) were used to determine forced expiratory pulmonary function and low back pain, respectively. Independent t-test and analysis of covariance were used for statistical analysis with a significance level of .05. The findings of this study were as follows: 1) There were no significant differences of ADIM effect on PEF and FEV1 between experimental group and control group. 2) There was a significant pain reduction in experimental group with ADIM. 3) PEF and FEV1 increased significantly in the fifth day compared with the first day pre-exercise baseline. Therefore, it is concluded that ADIM was effective in improving PEF and FEV1, and reducing VAS during forced expiration in patients with chronic low back pain.

An abdominal drawing-in maneuver (ADIM) with a pressure biofeedback unit can be used to prevent excessive lumbar lordosis during bridging exercise. Therefore, in this research, the effects of an ADIM on lumbar lordosis and lower extremity muscle activity during bridging exercise were investigated in thirty healthy adults. Surface electromyography (EMG) and VICON system were used to collect kinematic data and muscle activity, respectively. A paired t-test was used to determine a statistical significance. The results showed as follows: (1) When performing bridging exercise with an ADIM, the height of the anterior superior iliac spine and greater trochanter decreased significantly (p<.05). (2) When performing bridging exercise with an ADIM, the trunk extension angle and pelvic angle increased significantly (p<.05). (3) When performing bridging exercise with an ADIM, the EMG signal amplitude increased significantly in the rectus abdominis, internal oblique abdominis, external oblique abdominis, medial hamstring, and lateral hamstring (p<.05). (4) When performing bridging exercise with an ADIM, the EMG signal amplitude decreased significantly in the erector spinae (p<.05). From the result of this research, an ADIM trained with pressure biofeedback unit during bridging exercise is effective to prevent excessive contraction of erector spinae, to limit excessive motion of pelvis from sagittal plane and to increase muscle activity of abdominal muscles and hamstring muscle.

목적 : 본 연구의 목적은 손가락 폄근에 실시한 근전도 유발 전기자극 치료가 편마비 환자의 손기능 회복에 미치는 영향을 알아보고자 하였다. 연구 방법 : 20명의 뇌졸중 환자를 무작위로 EMG-stim군과 대조군에 각각 10 명씩 배정하였다. EMG-stim 군은 하루에 30분씩 2회, 주 5일, 10주 동안 (총 100회) 손가락 폄근에 EMG-stim 치료를 실시하였다. 반면, 대조군에게는 어떠한 치료도 실시하지 않았다. 손 기능을 검사하기 위하여 치료 전·후에 적분 EMG, 관절 운동 범위, 퍼듀 페그보드 검사를 EMG-stim군과 대조군 모두 실시하였다. 결과 : 치료 전·후 EMG-stim군은 적분 EMG, 관절 운동 범위, 퍼듀 페그보드 검사에서 유의하게 개선되었다(p<.05). 그러나 대조군은 유의한 차이가 나지 않았다(p>.05). 또한 집단 간 비교에서 EMG-stim 군은 대조군에 비하여 모든 종속 변수에서 유의하게 개선되었다(p<.05). 결론 : 본 연구에서 장기간 동안 집중적으로 실시한 EMG-stim 치료는 뇌졸중 환자의 손기능 회복에 효과적이라는 결론을 내릴 수 있다.

The purpose of this study was to examine the effect of the hip internal rotation on knee extensor and hip abductor electromyographic (EMG) activity during stair up and stair down mobility. Eighteen healthy subjects were recruited. All subjects performed stair up and down movements on a step of 30cm height while maintaining the hip in neutral (condition 1) and hip in internal rotation (condition 2). Surface EMG activity was recorded from five muscles (gluteus maximus, vastus lateralis (VL), vastus medialis oblique (VMO), posterior gluteus medius (Gmed), and tensor fascia latae (TFU)) and hip internal rotation angle was measured using a three dimensional motion analysis system The time period for stair up and down was normalized using the MatLab 6.5 program, and EMG activity was normalized to the value of maximal voluntary isometric contraction (%MVIC). The EMG activities according to the hip rotation (neutral or internal rotation) during the entire time period of stair up and down in each phase were compared using a paired t-test. During the entire period of stair up, the EMG activities of VL and TFL in condition 2 were significantly greater than in condition 1 (p<.05). During the entire period of stair down, the EMG activities of VL and TFL in condition 2 were significantly greater than in condition 1 (p<.05). However, the EMG activities of the other muscles were not significantly different between the conditions (p>.05). These results suggest that the stair up and down maintaining hip internal rotation was could be a contributing factor on patellar lateral tracking.

To reduce winging scapula, various exercise protocols have been widely used by clinicians. Selective serratus anterior strengthening, and restoring balanced function, are especially recommended to reduce winging scapula. The purpose of this study was to investigate visual biofeedback using a real time video camera display system for monitoring scapular winging during arm lowering. For this study, 13 males with winging scapular were recruited during arm lowering. Electromyography (EMG) activity was recorded from the serratus anterior (SA) and upper trapezius (UT) of the right side and compared with normal EMG activity using a paired t-test. The study showed, through visual biofeedback, that EMG activity significantly increased in the SA and significantly decreased in the UT (p<.05). These results suggest that visual biofeedback can be recommended as an effective method for scapular eccentric control, to prevent scapular winging during arm lowering.

The purpose of this study was to assess the influence of two shoe size conditions on foot pressure, ground reaction force (GRF), and lower extremity muscle fatigue. Seven healthy men participated. They randomly performed walking and running in two different conditions: proper shoe size and 10 mm greater than proper shoe size. Peak foot pressure, and vertical, anterior and mediolateral force components were recorded with the Parotec system and Kisler force platform. To assess fatigue, the participants performed treadmill running for twenty-five minutes twice, each time wearing a different shoe size. Surface electromyography was used to confirm localized muscle fatigue using power spectral analysis of four muscles (tibialis anterior, gastrocnemius medialis, rectus femoris, and biceps femoris). The results were as follows: 1) In walking conditions, there was a significantly higher peak pressure in the 10 mm greater than proper shoe size insole sensor 1, 2, 14, and 18 (p<.05). 2) In running conditions, there was a significantly higher peak pressure in the 10 mm greater than proper shoe size insole sensor 5, 14, and 15 (p<.05). 3) In walking conditions, there was a significantly higher first maximal vertical GRF in the 10 mm greater than proper shoe size (p<.05). 4) In running conditions, no GRF components were significantly different between each shoe size condition (p>.05). 5) Muscle fatigue indexes of the tibialis anterior and rectus femoris were significantly increased in the 10 mm greater than proper shoe size condition. These results indicate that wearing shoes that are too large could further exacerbate the problems of increased foot pressure, vertical GRF, and muscle fatigue.

The purpose of this study was to determine the influence of muscle fatigue in elbow flexors on the sense of force reproduction. Fifteen healthy subjects were recruited for this study. Maximum voluntary force (MVF) of elbow flexor muscles was measured by a digital tensiometer. Force errors were measured to test accuracy of the sense of force reproduction in elbow flexors. The subject was required to flex the elbow joint, to maintain and concentrate on about 20% of the MVF target force under visual feedback for 3 seconds. After a 5 second period rest, the subject was asked to duplicate the target force actively. Muscle fatigue was evoked with isometric contraction of the elbow flexors. Isometric contraction was continued until a 50% drop in MVF. The difference, in kilogram between the target force and the reproduced force was calculated for measuring force error. Force errors were compared between the non-fatigued condition and the fatigued condition by the paired t-test. Force errors were significantly increased in the fatigued condition compare to non-fatigued condition. This result suggests that the sense of force reproduction can be disturbed by localized muscle fatigue.

The purpose of this study was to investigate electromyographic activities of the flexor digitorum superficialis (FDS) and the flexor carpi ulnaris (FCU) by the shape of the ultrasound head. Twelve healthy subjects participated and performed ultrasound therapy with a round head and a long handled head during each 5-minute application. Electromyographic activities of the FDS and FCU were recorded by surface electrodes and normalized by maximal voluntary isometric contraction (MVIC) values. There was no difference in the muscular fatigue of FDS and FCU as determined by the shape of the ultrasound head (p>.05). Without the shape of head, the mean power frequency decreased with the time. There also was no difference in %MVIC of the FDS and FCU as determined by the shape of the ultrasound head (p>.05), but the force exerted exceeded 20%MVIC. There was however a significant difference in the amount of cumulative workload of the FDS and FCU as determined by the shape of ultrasound head (p<.05). The workload was however not affected by the shape of the ultrasound head. Constant static grasp of ultrasound transducer head during ultrasound therapy is considered a high risk factor of work-related musculoskeletal disease.

Reductions in strength and range of motion in older persons have been associated with decreased functional mobility and risk of falls. The purpose of this research was to investigate the effect of intensive dynamic balance exercise (DBE) during 8 weeks on onset time of medial gastrocnemius and tibialis anterior muscle contraction after perturbation in older women. Thirty subjects were randomly assigned into DBE group or control group. The DBE group participated in 50 minutes 3 days a week for 8 weeks. Surface electromyography (EMG) activity was recorded from the medial gastrocnemius and tibialis anterior muscles of left side. Outcome data were collected both groups at the pre-exercise and post-exercise. Independent t-test and paired t-test were used to determine the statistical difference. Results showed that the passive range of motion and functional reach test were significantly increased in the DBE group than the control group at the post-exercise (p<.05). The onset time of both muscles and discrepancy of onset time significantly reduced in the DBE group than the control group at the post-exercise (p<.05). The onset time of both muscles were significantly reduced in the post-exercise than the pre-exercise in the DBE group (p<.05). The discrepancy of onset time in the DBE group was significantly reduced in the post-exercise than the pre-exercise (p<.05). These findings suggest that intensive dynamic balance exercise for the eight weeks was effective in improving the postural control with older persons.

Muscle tone (stiffness/hardness) or muscle compliance changes during muscle contraction. The purposes of this study were to assess the intrarater and interrater reliabilities of the Myotonometer®, electronic device that quantifies muscle tone. Two raters used the Myotonometer to assess the right bicep brachia and quadriceps muscles of 30 voluntary persons without any orthopedic or neurological problems (age range, 18~21 yrs). Muscles were measured in a relaxed state and during brief sustained voluntary maximal isometric contraction. Intrarater correlation coefficients were calculated for each muscle and for each condition (relaxed and contracted). Intrarater reliabilities (intraclass correlation coefficients, ICCs) ranged from .778 to .954, relaxed, biceps brachia), .926 to .963 (contracted, biceps brachia), .935 to .990 (relaxed, quadriceps) and .679 to .952(contracted, quadriceps). Interrater reliabilities ranged from .652 to .790 (relaxed, biceps brachii), .813 to .907 (contracted, biceps brachii), .831 to .950 (relaxed, quadriceps) and .849 to .937 (contracted, quadriceps). Myotonometer measurements had high to very high intrarater and interrater reliability for measurements of the biceps brachia and quadriceps muscles.

The purpose of this study was to compare the onset times of muscle activities and the order of muscle firing in erector spinae, multifidus, rectus abdominis and biceps brachii during perturbation between subjects with and without work-related chronic low back pain (LBP). Twenty-nine subjects, 14 with and 15 without LBP, participated in this study. The muscle responses were measured by surface EMG (electromyography) during perturbation in eye opened and eye closed conditions. The EMG onset times of the erector spinae, multifidus, rectus abdominis and biceps brachii were similar between groups in eye closed condition. But the onset times of the erector spinae, multifidus, rectus abdominis were significantly delayed in subjects with LBP in eye opened condition. The results provide an evidence for impaired feed-forward control of the trunk muscles in subjects with LBP. Further studies are needed to identify whether the impaired feed-forward control of the trunk muscles is the contributing factor to LBP.

The purpose of this study was to find any correlations among Postural Assessment Scale for Stroke (PASS), Modified Barthel Index (MBI), Tone Assessment Scale (TAS), Motor Assessment Scale-Gait (MAS-G), Fugl Meyer-Balance (FM-B), and to predict MBI from subscales of the PASS. The subjects were 41 stroke patients of the Korea National Rehabilitation Center in Seoul. The main outcome measures were postural control (PASS), gait (MAS-G), Balance (FM-B), Tone (TAS), ADL (MBI). The data was analyzed using the Pearson product correlation. PASS scale was used between other clinical and instrumental indexes, multiple stepwise regression analyses were performed to identify prognostic factors for ADL incline, and Cronbach's alpha coefficient was used to identify internal consistency on PASS scale. The results of this study areas follows: 1. The highest level was sitting without support, the lowest level was standing on paretic leg on PASS scale. The highest level was chair/bed transfer, the lowest level was bathing on MBI. 2. All items of the PASS, except postural tone were significantly correlated with Gait, Balance, MBI (p<.01), 3. The Internal Consistency (Cronbach's alpha coefficient=.85) was very high, indicating that the PASS is homogeneous and is likely to produce consistent response. Furthermore, the sums of maintaining position items and of changing-position items were strongly correlated (r=.64, p<.05) and there were significant correlations between sums of PASS, sums of maintaining position items (r=.87, p<.01), and changing-position items (r=.93, p<.01). 4. The standing without support of the PASS items was the strongest variance (R²=.85) of the predicting ADL function. These findings provide strong evidence of the predictive value of the postural control on gait, Balance, ADL function in stroke patients and to can provide a reference for the successful therapeutic program and more improved functional recovery.

목적 : 본 연구는 만성 뇌졸중 환자를 대상으로 자세 조절이 일상생활동작 수행능력과 근 긴장도 변화 및 상지기 능 수행에 어떠한 영향을 미치는지 알아보고자 하였다． 연구방법 : 본 연구를 위하여 국립재활원에 입원한 41명의 뇌졸중 환자를 대상으로 모든 환자들은 자세조절 평가 척도(Postural Assessment Scale stroke, PASS), 일상생활동작 수행능력 측정 도구(Modified Barthel Index, MBI), 긴장도 사정 척도(Tone Assessment scale, TAS), Fugl-Meyer 평가 척도(Fugl-Meyer Assessment scale－upper extremity) 등을 이용하였고 자료 분석은 피어슨 상관분석(pearson correlation coefficient), 단계적 다중 회귀분석(stepwise multiple regression）을 실시하였으며 내적 일치도를 알아보기 위하여 Cronbach's alpha Coefficient를 구하였다． 결과 : PASS항목에서 가장 기능이 좋은 것은 지지하여 서기로 나타났으며，가장 기능이 낮은 것은 환측으로 서기였고，MBI항목에서 가장 기능이 좋은 것은 의자／침상 이동이며， 가장 기능이 낮은 것은 목욕하기로 나타났다．PASS의 모든 항목은 MBI, FM-UE, TAS와 유의한 상관관계(r=-33~91, p<.05~01）가 있으며，FM-U/E와 MBI(r=.35, p<.05), TAS- 안정(r=.-40, p,<．0.1), 연합항목(r=-.39,p<.05)에서 유의한 상관관계가 있는 것으로 나타났다．내적 일치도는 Cronbach's a=.86로 높게 나타났으며，PASS의 합과 자세유지 항목 (r=.90 p<.01)의 합，자세변화 항목(r=.93,p<.01)의 합은 유의한 상관관계가 있었으며，자세유지 항목의 합과 자세변화 항목의 합 간에는 유의한 상관관계(r=.69,p<.01)가 있었다．PASS 항목 중 누운자세에서 건측으로 돌기와 바닥에서 볼펜집어 올리기가 각각 ADL과 상지 기능을 예견하는데 가장 중요한 변수(R2=.95, R2=.56)임을 알 수 있었다． 결론 : PASS는 일상생활동작 수행 능력과 근 긴장도 및 상지기능수행 간에 유의한 상관관계가 있는 것으로 나타나 뇌졸중 환자의 기능적 독립성을 예측할 수 있는 지표가 될 수 있을 것이다．

The purpose of this study was to investigate the effect of submerged relaxation therapy for the spasticity on the affected side in three subjects with post-stroke hemiparesis. A single-subject alternating design with multiple baselines across individuals was employed in this study. Each subject alternately participated in a range of motion exercises on the mat and in the pool, and relaxation exercises in the pool. The muscle tone of the affected side was measured using the tone assessment scale (TAS). Measurements were made immediately and one hour following the intervention. The findings showed a therapeutic effect of submerged relaxation exercise on reducing spasticity for all subjects. The effect of submerged relaxation exercise on decreasing muscle tone was maintained for one hour measurements after the submerged relaxation exercise, although the mean TAS score assessed one hour after intervention was higher than that assessed immediately. The results of this study suggest that submerged relaxation exercise has a positive effect on decreasing spasticity on the affected side in persons suffering from post-stroke hemiparesis. Future research on submerged relaxation exercise should focus on objective evaluation and functional the aspects relevant to activities of daily living.

Ischemic stroke results from a transient or permanent reduction in cerebral blood flow that is restricted to the territory of a major brain artery. Thus, this study was performed to examine (1) the effects of swimming exercise on the improvement of muscle atrophy, and (2) exercise and HSP 70 expression in an ischemic stroke model induced by middle cerebral artery occlusion. The results of this study were as follows: One week after ischemic stroke was induced, changes appeared in the muscle weight of the gastrocnemius muscle due to muscle atrophy in the affected side. Group II showed statistically significant difference from group III eight weeks after ischemic stroke was induced. (p<.05). One week and eight weeks after ischemic stroke was induced there was significant decrease in the relative muscle weight of the gastrocnemius muscle in each group except Group IV, while there was statistically significant increase in group II eight weeks after ischemic stroke was induced, compared to group III (p<.05). For neurologic exercise behavior tests, Group II generally had the highest score, compared to other groups. In immunohistochemical observations, Group II showed a decrease in HSP 70. The above results suggest that swimming exercise improved muscle atrophy, changed the HSP 70 expression of ischemic stroke in rats, and contributed to the improvement of exercise function.

이 논문에서는 안정대륙권역(Stable Continental Regions, SCRs)에서의 중규모 지진에 의한 근단층지반운동(Near Fault Ground Motion, NFGM) 모델을 처음으로 제시한다. 근단층지반운동은 큰 진폭의 장주기 속도 펄스를 갖는 특징을 가지고 있다. 이 속도 펄스를 모델링하기 위해서는 그 주기와 진폭을 지진의 규모와 단층거리의 함수로 표현할 수 있어야 한다. 그런데 안정대륙권역에서는 관측 자료가 빈약하여 지진데이터로부터 이 관계식을 직접 유도하는 것은 어렵기 때문에 이 연구에서는 간접적인 접근법을 채택하였다. 속도 펄스의 주기와 진폭은 단층파열의 상승시간과 파열속도의 함수임이 알려져 있고 활성구조권역(Active Tectonic Regions, ATRs)에 속하는 미국 서부지역에서는 실험적 공식이 확립되어 있다. 안정대륙권역에서의 상승시간과 단층파열속도의 지진규모에 대한 함수관계는 WUS와 CEUS에서의 자료를 비교하여 도출하였다. 이 관계식들로부터 안정대륙권역에서의 NFGM의 속도 펄스의 주기와 진폭을 지진규모 및 단층 거리에 대한 관계식으로 유도하였다. 안정대륙권역에서의 NFGM의 가속도 시간이력은 추계학적으로 생성된 원역지진지반가속도에 새로운 관계식에 의한 속도 펄스를 중첩하여 얻어진다. 적용 예제로서 탄소성 단자유도 시스템의 근단층지반운동에 대한 응답을 분석하였다.

본 연구는 젊은층과 고령층을 대상으로 계단 상하행시 하지근군의 근전도(EMG; Electromyogram)를 측정하여 발휘근육부위와 근피로 정도와의 관계를 파악하기 위해 근전도 amplitude 분석을 실시하여, 비교하였다. 피험자는 젊은층과 고령층 각각 20명이었으며, 하지근 8부위(전경골근, 내측광근, 외측광근, 대퇴직근, 반건양근, 대퇴이두근, 내비복근, 외비복근)에 전극을 부착하여 계단 상하행 전후의 근전도를 측정하였다. 그 결과 젊은층은 계단 상하 보행 후 모든 측정 부위의 근전도 amplitude가 커졌으며, 고령층도 전경골근과 대퇴직근을 제외한 근육 6부위에서 근전도 amplitude가 커졌다. 또한 젊은층과 고령층의 amplitude 분석 값을 비교해 보면, 대퇴이두근과 내비복근을 제외한 모든 근육부위에서, 젊은층의 amplitude 값이 고령층에 비해 계단 상하 보행 전후 변화가 더 크게 나타났으며 특히 전경골근은 통계적 유의차가 인정되었다(p<0.05). 이와 같이 젊은층에 비해 고령층은 근육량이 적으므로 amplitude의 변화가 작은데, 노인들을 위한 제품 또는 환경 설계시 노인 근전도의 특성을 고려하여 측정하고 분석해야 할 것이다.

The purpose of this study was to identify the effect of the hip internal rotation on gluteal and erector spinae muscle electromyographic (EMG) activity during treadmill walking. Eleven healthy subjects were recruited. All subjects performed treadmill walking while maintaining the hip in neutral position (condition 1) and in internal rotation (condition 2). Surface EMG activity was recorded from four muscles (gluteus maximus (GM), gluteus medius (GMED), tensor fascia latae (TFL), and erector spinae (ES)) and the hip internal rotation angle was measured using a three dimensional motion analysis system. The gait cycle was determined with two foot switches, and stance phase was normalized as 100% stance phase (SP) for each condition using the MatLab 7.0 program. The normalized EMG activities according to the hip rotation (neutral or internal rotation) were compared using a paired t-test. During the entire SP of treadmill walking, the EMG activities of GM in condition 1 were significantly greater than in condition 2 (p<.05). The EMG activities of TFL and ES in condition 2 were significantly greater than in condition 1 (p<.05). The EMG activities of the GMED in condition 1 were significantly greater than in condition 1 (p>.05) except for 80~100% SP. Further studies need randomized control trials regarding the effect of hip internal rotation on the hip and lumbar spine muscle activity. Kinetic variables during gait or going up and down stairs are also needed.