• Title/Summary/Keyword: isokinetic

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Certification and Quality Control of the Official Test Facilities of Dioxins in Korea (국내 다이옥신 측정분석기관 지정 및 정도관리)

  • Jang, Seong-Ki;Kim, Tae-Seung;Lee, Won-Seok;Chung, Young-Hee;Choi, Doug-Il
    • Analytical Science and Technology
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    • v.13 no.5
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    • pp.675-682
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    • 2000
  • The concentration of dioxins from flue gases of municipal waste incineration facilities with capacities over 50 tons/day are regulated by the guideline: $0.1ng-TEQ/Nm^3$ for new facilities, and $0.5ng-TEQ/Nm^3$ for existing facilities and it will be strengthened to $0.1ng-TEQ/Nm^3$ until 2003 year. Dioxins from these incineration facilities have to be measured more than 2 times annually by the Official Test Facilities of Dioxins. Seven institutions have been certified so far as the Official Test Facilities of Dioxins. These facilities have to be evaluated by the quality control program provided by National Institute of Environmental Research every year. We reported the results of quality control test performed in 1999. Four institutions certified in 1998 sampled flue gases at stack of M incineration facilitiy and analyzed dioxins by Official Methods of Air Pollution. The isokinetic coefficients, the parameter for evaluation of sampling ability were excellent for all four institutions. They were 100.9%, 102.4%, 102.1% and 99.2%, respectively. The criteria required are as follows; resolution over 10,000, mass calibration within ${\pm}5ppm$, ion abundance ratio within 15%, and the recovery of 50-120%. As results, those institutions also met these parameters of Official Method of Air Pollution.

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Isokinetic Evaluation of Plantarflexors with Knee Position (슬관절의 자세에 따른 족관절 저측굴곡근의 등속성 근력 평가)

  • Bae Sung-Soo;Lee Hyun-Ok;Lee Keun-Heui
    • The Journal of Korean Physical Therapy
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    • v.12 no.2
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    • pp.145-152
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    • 2000
  • Pcak torque. angle of peak torque occurrence. total work, average power. endurance of the ankle plantar flexors were studied with the knee positioned $0^{\circ}\;and\;90^{\circ}$ flexion. Plantar flexors of 20 students were tested on Cybex 6000 dynamometer. The results were as fallows ; 1. The peak torque values were significantly higher with knee extension than knee $90^{\circ}$ flexion. 2. The angle of peak torque occurrence were earlier with knee extension than knee $90^{\circ}$ flexion, but no significant. 3. The total work were significantly higher with knee extension than knee $90^{\circ}$ flexion. at$30^{\circ}/sec$, but no significant at $90^{\circ}/sec$ 4. The endurance ratio were higher significantly with knee $90^{\circ}$ flex ion than knee extension 5. The mean average power were significantly higher with knee extension than knee $90^{\circ}$ flextion

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The Effect of an 8-week Shoulder Strengthening Exercise on Shoulder Muscle Strength of Caregivers (8주간의 어깨 강화 운동이 요양보호사들의 어깨 근력에 미치는 영향)

  • Shin, Jae-Wook;Lee, Seung-Min;Jung, Dae-Youn;Kim, Dong-In;Park, Jae-Sung;Lee, Byeong-Soo;Song, Se-Hee;Park, Lee-Dae;Kim, Moon-Jeong;Kim, No-Yong;Lee, Kwang-Hoon;Kim, Jae-Yong
    • PNF and Movement
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    • v.16 no.1
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    • pp.43-50
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    • 2018
  • Purpose: This study examined the effects of a shoulder-strengthening exercise on muscle strength of shoulder flexors and extensors of caregivers. Methods: The study consisted of 19 caregivers (2 males and 17 females) employed by Medical Center B. All the participants took part in an 8-week shoulder muscle strengthening exercise, based on previous studies. In the first week, the subjects took part in a stretching exercise enhance the range of motion. In the second week, they participated in an exercise aimed at improving shoulder blade stability. From the third to seventh weeks, a resistance exercise of different intensities was applied in a phased manner. Finally, in the eight week, the subjects took part in plyometric exercise. Peak torque, average power, and total work of shoulder flexors and extensors in both sides were measured before and after the exercise at an angular speed of 120deg/sec using an isokinetic device. Wilcoxon's singed-ranks test was conducted to analyze differences in muscle strength before and after the intervention. Results: After the exercise, there was a significant improvement in peak torque and average power of flexors of the right arm. After the exercise, peak torque, total work, and average power showed a significant improvement in the flexors of the left arm (p<0.05). However, there was no statistically significant difference in extensor muscle strength in either arm after the exercise. Conclusion: Shoulder flexors of caregivers are utilized frequently in the workplace. Implementation of extensor-strengthening exercises, in addition to flexor-strengthening exercises, can contribute to reducing the incidence rate of shoulder injuries among caregivers.

A Biomechanical Comparative Analysis of the Multi-Radius Total Knee Arthroplastry System for Go up Stair and Go down Stair (계단 오르기와 내리기 동안 다축범위(multi-radius) 무릎인공관절 수술자의 운동역학적 비교분석)

  • Jin, Young-Wan;Yoo, Byung-In;Kawk, Yi-Sub
    • Korean Journal of Applied Biomechanics
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    • v.16 no.1
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    • pp.31-41
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    • 2006
  • The primary purpose of a TKA is to restore normal knee function Therefore, ideally, a TKA should: (a) maintain the natural leverage of the knee joint muscles to ensure generating adequate knee muscle moments to accomplish daily tasks such as rising from climbing stairs; (b) provide adequate knee joint stability. A 16-channel MyoResearch XP EMG system was used to collect the differential input surface electromyography signals VM, VL, RF, BF, ST during climbing/descending stair tests. A Peak Motion Measurement System was used to collect the kinematic and kinetic data. AKIN-COM Ill isokinetic dynamometer was used for EMG of VM, VL, RF, BF and ST during maximal voluntary contraction. I Quadriceps EMG results for the VM of the passed 1year group limb demonstrated significant less RMS EMG than that of the passed 3year group limb $60^{\circ}-15^{\circ}$ of knee flexion(p<0.05). The VL of the passed 1year group limb also demonstrated significants less RMS EMG than that of the passed 3year group limb from $60^{\circ}-45^{\circ}$ of knee flexion(p<0.05). Similar to the VM and VL, the RF of the passed 1year group limb showed less RMS EMG than that of the passed 3year group limb from $60^{\circ}-30^{\circ}$ do knee flexion(p<0.05). Hamstring EMG results for the BF of the passed 1year group limb demonstrated less RMS EMG than that of the passed 3year group limb from $75^{\circ}-15^{\circ}$ of knee flexion(p<0.05). The passed 1year group limb tended to have less ADD displacement(p<0.071) than that of the passed 3year group limb. There was no significant difference of the ABD displacement between the passed 1year group and the passed 3year group limbs(p<0.73). The passed 3year group used compensatory adaptation movement strategies to compensate for the strength deficit of passed 3year group limbs. The passed 3year group limb also increased the quadriceps muscle activation level to produce more knee extension moment to compensate for the short quadriceps moment arm. The passe 3year group limb might have an unstable knee joint in the medio-Iateral direction during the climbing/descending by showing a tendency of more ADD displacement and greater hamming co-activation EMG than the passed 1year group limbs. The TKA design was not able to help the knee joint to produce adequate knee extension moment with less quadriceps muscle effort. I think that old man needs continuous exercise for muscle strength.

Functional analysis of isolated posterior cruciate ligament deficient subjects (후방 십자 인대 단독 손상 환자의 기능적 분석)

  • Kim Jin Goo
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.3 no.1
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    • pp.66-72
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    • 2004
  • Purpose: To evaluate the compensatory mechanism in vivo and develop the treatment guide by performing the comprehensive functional tests of the posterior cruciate ligament (PCL) deficient subjects. Material and Methods: 10 PCL deficient subjects and 10 healthy control group were evaluated. Performed functional tests were range of motion, posterior drawer test, Telos, 30$^{\circ}$ flexion wt-bearing view, KT-1000 arthrometer, gait analysis, EMG test and isokinetic tests. Results: Physical, KT-1000, Telos posterior tests showed significant differences, but 300 full weight bearing lateral view, muscle strength test revealed no difference between two groups. Less knee flexion at initial contact and reduced maximum valgus moment were observed in PCL deficient group. In vertical drop landing, PCL group had increased plantar flexion angle at initial contact. Conclusion: Compensatory mechanisms such as reduced unstable components and absorbing the maximal load of the joint were occurred after PCL insufficiency, which result in good clinical and functional outcomes. Further investigations would be needed to understand the functional adaptations of PCL deficient subjects.

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Evaluation of Muscle Fatigue Recovery Effect and Meridian Potential Change using Magnetic Acupuncture System (자화침 시스템을 이용한 경락전위 유발효과 및 근피로 회복 평가)

  • Kim, Soo-Byeong;Park, Sun-Woo;Ahn, Soon-Jae;Lee, Na-Ra;Lee, Seung-Wook;Min, Se-Eun;Kim, Young-Ho;Lee, Yong-Heum
    • Korean Journal of Acupuncture
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    • v.29 no.1
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    • pp.83-92
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    • 2012
  • Objectives : The purpose of this research was to develop the magnetic acupuncture system which used solenoid coil for magnetizing acupuncture needle. The system could generate the meridian electric potential (MEP) similar to the potential by manual acupuncture. Thus, we tried to confirm the therapeutic effect that is caused by the MEP generation. Methods : To confirm the MEP, we stimulated the magnetic acupuncture with at 2Hz, $92.7{\pm}2mT$, PEMFs (Pulsed Electro-Magnetic Fields) at ST37 and measured the evoked potential between ST36 and ST41. Also, we conducted a fatigue recovery test using isokinetic exercise in order to identify the therapeutic effect on musculoskeletal disorders. We chose LR9 as a stimulation point. To observe the state of fatigue, we measured the EMG and analyzed median frequency and peak torque for 20minutes. Results : We observed that MEP which incurred from magnetic acupuncture was higher than he reported MEP induced by manual acupuncture. Moreover, its modes were divided into two types by the direction of magnetic flux. When generating magnetic flux in the direction of acupoint, the positive peak voltage of the MEP was generated. In contrast, negative peak voltage of the MEP was generated whenever meganetic flux generated in the outward direction. As a result of fatigue recovery, the median frequency (MF) of the magnetic acupuncture group were recovered faster than that of the non-stimulation group. However, the peak torques of both groups were not restored until after 20 minutes. Conclusions : We confirmed that the magnetic acupuncture system can lead to the MEP similar to manual acupuncture. Moreover, the MEP had a therapeutic effect on the musculoskeletal disorders.

Changes in Inflammatory Mediators, Immunocompetent Cells and Bone Merrow Progenitor Cells by the Magnitude of Muscle Damage and Type of the Muscle Contraction in the Elderly (고령자의 근육수축양식 및 손상정도에 따른 염증물질, 면역적격세포 및 골수유래 전구세포의 변화)

  • Song, Sang-Hyup;Lee, Ho-Seong
    • 한국체육학회지인문사회과학편
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    • v.54 no.5
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    • pp.769-780
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    • 2015
  • This study investigated the changes in inflammatory mediators, immunocompetent cells and bone merrow progenitor cells by the magnitude of muscle damage and type of the muscle contraction in the elderly. Twenty older adults who had not been involved in a resistance-training program at least 6 months prior to the present study were assigned to eccentric exercise group (ECC, n=10) and concentric exercise group (CON, n=10). All subjects performed 10 sets of 6 maximal isokinetic eccentric (ECC 1) or concentric (CON) contractions with the non-dominant arm in a randomized, with 4 wk between bouts (ECC 2). Skeletal muscle damage index (ROM, VAS, Plasma CK), inflammation mediators (TNF-α, IL-1, IL-6), immunocomperent cells (CD3+, CD4+, CD8+, CD19+), bone merrow progenitor cell (CD34+) and leukocytes were measured before, immediately after, 2, 24, 48, 72, and 96 h after exercise. Changes in ROM and VAS were greater (P<.05) after ECC 1 than CON and ECC 2. Increases in TNF-α and IL-6 were greater (P<.05) 24, 48 and 72 h after ECC 1 than CON and ECC 2. Increases in neutrophils were greater (P<.05) 2 h after ECC 1 than CON and ECC 2. It was confirmed that muscle damage was greater following eccentric than concentric contractions as well as first bout than second bout in the elderly, and suggested that TNF-α, IL-6 and neutrophils should closely correlate with magnitude of muscle damage.

Effect of Low-intensity Resistance Training with Blood Flow Restriction on Muscle Volume and Strength in Elderly Women (저강도의 저항성 운동 시 혈류제한 적용이 노인여성의 근 비대와 근력 향상에 미치는 영향)

  • Yeo, Hyo-Seong;Kim, Hyo-Jeong
    • 한국체육학회지인문사회과학편
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    • v.54 no.1
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    • pp.535-544
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    • 2015
  • This study was performed to determine the effect of low-intensity resistance training with blood flow restriction (BFR) on muscle volume and strength in elderly women. Sixteen elderly women (70.9±4.6 years) were divided into low (30% 1RM) and high (75% 1RM) intense resistance training groups. Tourniquet cuff (Zimmer, Germany) for BFR was applied only to the right leg during the training period. All subjects performed unilateral leg press, leg extension and leg curl (3 sets×12 repetitions) for 10 weeks (2d/wk). Blood pressure was increased from 110 to 240 mmHg during the training period at the most proximal region of exercised leg. Muscle volume and cross-sectional area (CSA) were measured by MRI and body composition was monitored by dual-energy X-ray absorptiometry (DEXA) and isokinetic muscular strength were analyzed in both legs. The quadriceps CSA (15.2%, p<.001) and muscle volume (13.8%, p<.001) were increased in high-intense trained leg with BFR and the increased rate was highest among groups. The quadriceps CSA (9.8%, p<.001) and muscle volume (6.9%, p<.001) were increased in low-intensity training group with BFR and their increased rates were higher than control groups. The strength by exercise training was significantly improved in all groups and tended to be higher in BFR groups. These results demonstrate low-intensity resistance training with blood flow restriction could be an effective way to improve muscle volume and strength in elderly women.

Effects of Shoulder Muscle Strength on Terminal Range by Humeral Head Retroversion (상완골 후경각이 가동역에 따른 견관절 근력에 미치는 영향)

  • Park, Si-Young;Lee, Dong-Jun
    • Journal of Life Science
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    • v.20 no.4
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    • pp.549-554
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    • 2010
  • Increased external rotation and decreased internal rotation have been noted to occur progressively in the throwing shoulders of baseball pitchers. The purpose of this study was to provide descriptive data for terminal range eccentric antagonist/concentric agonist shoulder muscle strength in collegiate baseball pitchers with humeral head retroversion diagnosed through MRI. The dominant and non-dominant shoulders of 9 asymptomatic baseball pitchers were tested through a range of 20 degrees of external rotation to 90 degrees of internal rotation using the Biodex system 3 isokinetic dynamometer at speeds of $90^{\circ}/s$ and $180^{\circ}/s$. Differences between the dominant and non-dominant shoulders were assessed using the paired samples t-test. Total range of motion, measured at $90^{\circ}$ of glenohumeral abduction, was $180.1^{\circ}$ for dominant shoulders and $183.7^{\circ}$ for non-dominant shoulders. Humeral head retroversion measured $47.6{\pm}6.1^{\circ}$ in dominant and $37.8{\pm}5.3^{\circ}$ in non-dominant extremities. The mean internal rotator concentric contraction (IR-Con) showed a significant difference compared to $31.5{\pm}5.1$ (Nm) in dominant and $38.7{\pm}5.2$ (Nm) in non-dominant shoulders at $180^{\circ}/s$ (p<0.05). The mean external rotator eccentric contraction (ER-Ecc) showed a significant difference compared to $20.3{\pm}4.7$ (Nm) in dominant and $25.1{\pm}3.7$ (Nm) in non-dominant shoulders at $90^{\circ}/s$ (p<0.05). There is a pattern of increased external rotation and decreased internal rotation in the dominant extremity that significantly correlates with an increase in humeral retroversion.

The results of arthroscopic repair according to the delamination of rotator cuff (회전근 개 판분리 파열에 따른 관절경하 회전근 개 봉합술의 결과)

  • Ku, Jung Hoei;Cho, Hyung Lae;Park, Man Jun;Kim, Jeong Cheol
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.10 no.2
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    • pp.61-68
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    • 2011
  • Purpose: We evaluated the clinical outcome after arthroscopic repair in full thickness rotator cuff tears with and without delamination. Materials and Methods: From March 2006 to October 2008, we included 48 consecutive shoulders (31 males, 17 females; mean age 57.6 years; 45~68) who had arthroscopic double row repair for fullthickness tears of the rotator cuff. Mean rotator cuff tear size was 2.8 cm (range: 1.2~3.6) and the techniques of tendon-to-bone fixation varied according to the presence of delamination; separate row fixations of bursal and articular layer were used in delaminated tear. The mean follow-up was 26 months (range: 18~33) and functional and structural results were evaluated by American Shoulder and Elbow Surgeons (ASES), University of California at Los Angeles (UCLA) scale, isokinetic strength testing and magnetic resonance imaging (MRI) obtained mean 8 months (range:6~13) postoperatively. The patterns of delamination, age, sex, symptom duration, size of tear, satisfaction rate, retear rate ware compared and significance was set at p values < 0.05. Results: Postoperative functional shoulder score improved significantly in 44 shoulders (91.7%). Delamination was observed in 15 shoulders (31%) and it extended proximally and posteriorly in the majority of shoulders, and the articular layer was thicker (8/15, 53%) and more retracted (9/15, 60%) compared with the superficial bursal layer. Final follow up functional shoulder scores showed no differences between non-delaminated and delaminated tears and the presence of delamination had no correlations with sex, symptom duration, tear size and satisfaction rate, however, older age had more delaminated tears (p=0.041). Follow up MRI in 29 shoulders revealed that fourteen (48%) shoulders had complete healing; nine (31%), partial healing; six (21%), complete retear but the half of the retear group showed favorable clinical results. 79% (15/19) in non-delaminated tear and 80% (8/10) in delaminated tear were judged as healed tendon on MRI and double-layer double row repairs in delaminated tears resulted in nearly same rate of structural integrity of single-layer double row repairs (p=0.165). Conclusion: The incidence of delamination in our series was 31% and older age had more delaminated tears. Sex, symptom duration, preoperative size of the tear, functional results and satisfaction rate had no significant correlations with the presence of delamination. Nearly the same postoperative structural integrity was noted in both delaminated and non-delaminated tears.

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