Background: Forward head posture affects many individuals and can cause pain and dysfunction in the muscles and joints of the head, neck, and shoulders. Objectives: This study aimed to assess muscle activity and onset time of cervical and scapular muscles during 180° shoulder flexion and abduction in individuals with normal head posture (NHP) and in those with forward head posture (FHP), both before and after correction. Design: Cross-sectional study. Methods: Thirty-six individuals were divided into FHP and NHP groups. Muscle activity and muscle contraction onset time of the splenius capitis, sternocleidomastoid, upper middle and lower trapezius, and serratus anterior muscles were measured during shoulder flexion and abduction using wireless surface electromyography. Results: The FHP group exhibited increased muscle activity compared to the NHP group (P<.05), notably in the sternocleidomastoid and middle trapezius muscles, more so during shoulder abduction than flexion (P<.05). Regarding muscle contraction onset time, sternocleidomastoid onset was fastest during shoulder abduction in the FHP group (P<.05), while serratus anterior onset was slowest during both shoulder abduction and flexion (P<.05). Conclusion: These findings highlight distinct muscle activity and muscle contraction onset time patterns based on head posture and shoulder movement. Selective muscle activation strategies may help reduce heightened sternocleidomastoid and trapezius activity and enhance serratus anterior engagement in individuals with FHP.
P파와 S파의 도착시간 정보는 지진 발생위치 결정, 1차원 및 3차원 지하구조 등 지진학 연구 수행에 중요한 정보이다. 최근 지진관측소의 수가 비약적으로 증가함에 따라 관측망을 운영하면서 수동으로 지진파의 도착시간을 측정하는 것은 상당한 시간이 소요되는 일이 되었다. 본 연구에서는 진원요소에 대한 사전정보(지진 발생위치와 시간)를 확보 할 수 있는 경우 Akaike Information Criterion (AIC)을 적용하여 추가의 관측소에서 국지지진의 P파와 S파의 도착시간을 자동측정하였다. 해당 방법을 경산(DAG2) 지진관측소에 기록된 자료에 적용한 후 수동 측정한 값과 자동 측정한 값을 비교한 결과 P파의 경우 95.1%, S파의 경우 93.7%가 0.1초 이하의 차이를 보이면서 결정되는 것을 확인하였다. 자동측정결과의 높은 정확성은 향후 고밀도 지진관측망 운영에 성공적으로 적용될 수 있음을 시사한다.
The purpose of this study was to investigate the effects of vibration on Golgi tendon organ(GTO) and Hold-Relax of PNF in muscular activity and gait factors on Delayed Onset Muscle Soreness(DOMS). This study was conducted on 20 subjects. they were divided into two groups; Hold-Relax of PNF(n=10), Vibration on GTO(n=10). Both of the group was performed interventions 1 times a day for 3 days. The data was analyzed by the repeated-ANOVA for comparing before, after 24h and after 48h changes of factors in each group and the Independent t-test for comparing the between groups. The results are as follows. There was statistically significant difference of before, after 24h and after 48h vibration on GTO group and Hold-Relax of PNF group in muscular activity and gait factors on DOMS.(p<0.05). There was no statistically significant difference of between vibration on GTO group, but there was statistically significant difference Hold-Relax of PNF group in EMG, step width, step length, stride length(p>0.05). As a results of this study, Hold-Relax of PNF group are effective in improving muscular activity and gait factors
목적 : 생애사적 연구방법을 사용하여 근위축성측삭경화증 클라이언트의 삶을 이해하고 발병 후 겪게 되는 신체적, 심리적 경험들을 심도 있게 이해하고자 하였다. 이를 바탕으로 클라이언트에게 효과적인 작업치 료 중재방법을 위한 기초자료로 활용하고자 한다.
연구방법 : 근위축성측삭경화증이 진행되는 과정에서 변화하는 신체적 기능과 심리적 변화를 구술할 수 있 는 참여자 2명을 대상으로 하였다. 더 이상 새로운 것이 나오지 않을 때까지 심층면접을 30분씩 7~10 회 실시하였다.
결과 : 두 명의 참여자들은 체중의 변화, 사지의 변화, 호흡근의 변화와 연하장애 등 신체적인 경험은 같았 다. 심리적인 경험은 차이가 있었는데 진단을 받은 후 가족의 지지가 없던 참여자 김은 희망보다는 죽음 을 무덤덤하게 받아들였으나, 가족의 지지를 받고 있던 참여자 최는 죽음보다는 희망을 가지고 살아갔지 만 시간이 지남에 따라 죽음에 대해 준비하는 모습을 보였다.
결론 : 근위축성측삭경화증을 가지고 있는 클라이언트에게 작업치료사의 역할은 초기에는 신체적・심리・사 회적 기능 등의 변화에 대한 공감과 이해를 할 수 있는 재활전문가로서 수행을 하고, 말기로 진행되면서 호스피스 전문가로서의 역할을 수행해야 한다.
Delayed onset muscle soreness (DOMS) is a painful condition that arises from e+M8xercise-induced muscle damage after unaccustomed physical activities. Various therapeutic interventions have been applied to reduce the intensity and duration of DOMS-related symptoms. Recently, pulsed electromagnetic field (PEMF) intervention has been introduced as an alternative noninvasive treatment for DOMS. This randomized, double-blind, placebo-controlled experiment was conducted to examine the effects of PEMF therapy on DOMS in elbow flexors at 24, 48, and 72 hours after the experimental DOMS induction. Thirty healthy volunteers ( yrs, cm, and kg) participated in this study. Each was randomly assigned to a PEMF or placebo group. On the first day, DOMS was induced in the elbow flexors by repeated isokinetic motions at low () and fast () speeds in all subjects. Thereafter, the PEMF group received 15-min daily treatment with a PEMF device. The placebo group received sham treatment of the same duration. Overall, PEMF application was more effective than the sham treatment in reducing the physiological symptoms associated with the DOMS including perceived soreness, median frequency, and electromechanical delay of the surface electromyography. In addition, median frequency and isokinetic peak torque of the PEMF group recovered to the pre-DOMS induction level earlier than the placebo group. In conclusion, this study suggests that PEMF can be applied as a new recovery strategy in reducing DOMS symptoms. Further experiments are required to examine the effect of the PEMF treatment on different types of exercise conditions and to determine the optimal treatment dosage and duration in a real clinical setting.
The purpose of this study was to determine the effects of warm-up and cool-down exercises on pain and muscle activation of delayed onset muscle soreness after intense exercise. Delayed onset muscle soreness was caused by the eccentric exercise in the elbow flexor muscle of the non-dominant upper limb. Forty-four subjects volunteered to participate in this study and were randomly assigned to one of the following groups: warm-up and cool-down group, only warm-up group, only cool-down group, or control group with no intervention. The level of perceived pain using the visual analogue scale and electromyographic activation change in maximal voluntary isometric contraction were measured 4 times at the following times: 10 min, 24 hr, 48 hr, and 72 hr after the exercise. The results revealed the main effect between the groups and interaction effect between the group and measurement session (p<.05). The warm-up and cool-down group showed most favorable results with respect to reduced perceived pain level and increased muscle strength in most measurement sessions, and the only warm-up group showed significantly more decreased pain level than the control group at 24 hr and 48 hr and more increased muscle activation than the cool-down group at 48 hr (p<.05). However, there were no significant differences in pain level and muscle activation between the only cool-down group and control group at all measurement sessions (p>.05). The findings suggest that the warm-up exercise performed before an intense exercise had beneficial effects on the symptoms of delayed onset muscle soreness, whereas cool-down exercise performed after the intense exercise did not.
본 논문에서는 진동중인 교량 단면에 작용하는 풍하중을 산정하고 그에 따른 플러터 발생풍속을 예측하기 위하여 분산형 전산환경을 활용한 수치해석 연구를 수행하였다. 분산형 전산환경은 웹 포탈을 기반으로 수치해석 환경을 제공하는 일종의 수치풍동 시스템으로서, 전산유체역학 (CFD: Computational Fluid Dynamics) 에 대한 전문지식이 부족한 사용자들도 격자생성, 수치해석자를 이용한 계산, 가시화 등의 전 과정을 편리하게 수행할 수 있는 차세대 토목분야 계산 환경이다. 본 연구 환경의 검증을 위해 수치해석자에 적용된 지배방정식은 2차원 비정상 Navier-Stokes 방정식으로서, 교량의 움직임을 모사하기 위하여 동적격자 기법을 도입하였다. 또한 계산된 비정상공기력을 적용하여 플러터 발생풍속을 산정하였으며, 그 결과는 기존의 실험결과와 잘 일치함을 확인하였다.
목적: 근시발생 시점에 따른 굴절이상도와 안광학상수의 차이를 분석하여 근시 발생의 요인을 알아보고, 1년간의 변화를 분석하여 각 그룹의 근시진행 원인을 알아보고자 한다. 방법: 2008년 3월과 2009년 3월 2회에 걸쳐 76명(남 23명, 여 53명)을 대상으로 기본신체검사, 자동굴절검사, 각막곡률반경, 전방깊이, 안축장을 조절마비 상태에서 측정하고 등가구면 굴절이상도가 -0.50D 이상인 피검자(46명, 92안)를 대상으로 안경이나 콘택트렌즈로 교정한 시기에 따라 조기발생 근시군과 만기발생 근시군으로 구분하였다. 결과: 조기발생 근시군의 등가구면 굴절이상도는 -4.25±2.05D로 만기발생 근시군의 -2.63±1.69D보다 근시도가 컸으며 안축길이도 조기발생 근시군이 25.464±1.059 mm로 만기발생 근시군의 24.850±0.867mm보다 더 길었다. 1년간의 등가구면 굴절이상도 변화는 조기발생 근시군이 -0.08±0.28D, 만기발생 근시군이 -0.32±0.36D로 만기발생 근시군에서 근시도가 더 증가하였다. 조기발생 근시군에서 등가구면 굴절이상도 변화와 각막곡률반경 사이에는 양의 상관성(r=0.627, p=0.000)이 있었고 AL/CR비 변화와는 음의 상관성(r=0.487, p=0.000)이 있었다. 만기발생 근시군의 등가구면 굴절이상도 변화와 각막곡률반경 사이에는 양의 상관성을(r=0.651, p=0.000), AL/CR비 사이에는 음의 상관성을 보였다(r=0.710, p=0.000). 결론: 이상으로부터 근시발생 시점이 빠를수록 안축길이가 더 길었으며 근시도가 더 큰 것으로 나타났다. 근시도 증가는 조기발생 근시군에 비해 만기발생 근시군에서 더 크게 나타났다.
This study examined the vastus medialis oblique (VMO) and the vastus lateralis (VL) onset time differences (OTD) during quadriceps contraction in different hip positions. Twelve healthy subjects were recruited (four men, eight women). Surface EMG activities of the VMO and VL were measured during a quadriceps strengthening exercise in a long sitting condition and in a sitting at a chair with feet hanging condition. For each condition, subjects were tested in two hip positions (neutral and adduction). The OTD between the two muscles was calculated for each condition, by subtracting the onset time of the VL from the VMO. Therefore, the negative value of OTD represent earlier EMG onset of the VMO compared to the VL. The OTD was not significantly different between the hip neutral and the hip adduction position in the long sitting condition (p=.064). However, the OTD was significantly different between the hip neutral position (15.83±109.51 ms) and hip adduction position (-5.58±121.08 ms) during the sitting at a chair with feet hanging condition (p=.047). The negative OTD value in the hip adduction condition during quadriceps strengthening exercises is the result of earlier onset of the VMO than VL. Therefore, quadriceps contraction in the hip adduction position can prevent the risk of patella lateral tracking. We expect that quadriceps strengthening exercise in the hip adduction position will be a safe way to prevent patellofemoral pain syndrome resulting from abnormal patella lateral tracking.
This study examined the effects of hold-relax with agonist contraction (HR-AC) on the symptoms of delayed onset muscle soreness (DOMS) induced by intensive eccentric exercise of the non-dominant biceps brachii. Ten men (mean age=26.7 yrs, mean height=172.1 cm, mean weight=66.2 kg) and ten women (mean age=27.4 yrs, mean height=165.9 cm, mean weight=60.7 kg) who had not participated in a regular exercise program for the upper extremities in the previous six months were randomly assigned to one of two experimental groups: the HR-AC group, or the control group. We measured joint range of motion (ROM), maximal voluntary isometric contraction (MVIC), and muscle soreness before eccentric exercise, and 24, 48, and 72 hours after eccentric exercise. The subjects in the HR-AC group received the HR-AC technique in the non-dominant biceps brachii. The HR-AC technique was applied 24 and 48 hours after eccentric exercise. There was no significant difference between the HR-AC and the control group. However, the HR-AC group, compared to the control group, had a significant difference between the time points of the various parameters. Increased ROM (p<.05), decreased muscle soreness (p<.05), and reduced MVIC (p<.05) were found in the HR-AC group after 72 hours. Decreased ROM (p<.05) and MVIC (p<.05), and increased muscle soreness (p<.05) were observed in the control group. These findings suggest that the HR-AC technique effectively reduces muscle soreness and increases ROM 72 hours after eccentric exercise.
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.
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 investigate the effects of hip extension velocity (7.5 degree/second, 30 degree/second) on the relative onset time of the gluteus maximus in relation to the hamstring during hip extension in prone position. Thirteen healthy male subjects (mean age=22.6 years [SD=1.8], mean weight=73.4 kg [SD=10.3], mean height=176.1 cm [SD=6.3]) voluntarily participated in this study. Electromyographic data was collected on the gluteus maximus and hamstring to determine onset time. Statistical analyses were performed with the paired t-test. The results showed that the onset time of the hamstring was significantly faster than that of the gluteus maximus in both fast and slow hip extension velocity. The gluteus maximus began contraction .079 seconds later following the contraction of the hamstring. The onset time of the hamstring was significantly faster in fast hip extension velocity compared with slow hip extension velocity. In conclusion, it was determined that the onset time of the gluteus maximus was faster with fast hip extension velocity compared with slow hip extension velocity. There was a statistically significant difference between the onset times of the gluteus maximus and hamstring in relation to the two velocities (p<.05). Further study is needed to examine whether the velocity of hip extension can influence the onset time in a similar fashion in patients with low back pain.
The purposes of this study were to determine the effects of rehabilitation programs on functional performance of the lower extremities and whether additional therapeutic exercise with routine rehabilitative therapy improves functional performance more than just routine rehabilitative therapy by it self for inpatients who have suffered a stroke with below moderate severity within 3 to 6 months after the onset of the stroke. Fifty-eight subjects were divided into two groups. Group I was given routine rehabilitative therapy and group II was given additional therapeutic exercise along with the routine rehabilitative therapy. Each group received 6 weeks of rehabilitation. The timed get-up and go test (TUG), the Fugl-Meyer score (FMS), functional independence measure (FIM), functional reach (FR), gait velocity (GV), and the strength of knee extensor and flexor were selected to measure effect of rehabilitation programs. The main results were measured and analysed at baseline, 3 weeks, and 6 weeks after the start of the rehabilitation programs. The results revealed that all of functional performance of the lower extremities in 3 weeks after the start of the rehabilitation programs were significantly improved compared with before the rehabilitation programs in both groups. In 6 weeks, TUG, FIM, FR, GV, and the strength of knee extensor in group I, TUG, FMS, FIM, FR, GV, and the strength of knee extensor and flexor in group II were significantly improved compared with the results after 3 weeks. At 3 weeks after rehabilitation programs, group II made significantly greater gains in TUG, FR, GV, and the strength of the knee flexor compared to the group I. At 6 weeks, group II made significantly greater gains in TUG, FR, GV, and the strength of the knee extensor and flexor compared to the group I. In conclusion, rehabilitation programs for stroke patients within 3 to 6 months after stroke onset significantly contributed to improve functional performance of the lower extremities. It is desirable for improvement of functional performance of the lower extremities to perform additional exercise with routine rehabilitative therapy.