• Title/Summary/Keyword: Maximum Contraction

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A Study on the Variation of the Body surface Area by the Arm movements to Somatotype -The Subject of the College Men- (체형별 상복동작에 따른 상체의 체표면 변화에 관한 연구 -남자대학생을 중심으로-)

  • 김진경
    • Journal of the Korean Home Economics Association
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    • v.26 no.2
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    • pp.1-13
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    • 1988
  • The purpose of this study was to classify somatotype of males, to show changes of the body skin surface by the somatotype. The size of sample was 156 males between age 20 and 24. Somatotype classified into Bending somatotype, Standard somatotype, Turning over somatotype. And according to the somatotype, changing of the upper part of the body by the arm movements analyzed through gypsum experiment. The result obtained from this study were as follows; 1. the variation of the upper part of the body form by changing the am movements, by the increasing of movements, shoulder-point ws moved to be inside or upside, the anterior armpit point & armpit point were moved to the upside. 2. As a result of investigating into the rate of the expansion and contraction of the basic lines and body surface area by the arm movements, the rate of expansion and contraction of the basic lines by the arm movements, the side sea length showed the maximum rate of extension in 135 degrees, the shoulder length showed the maximum rate of contraction in 135 degrees. The rate of expansion and contraction on the body surface area by the arm movements showed the phenomenon of contraction, of items F1, F6, B1, B9 showed the phenomenon of extension, of items F3, F4, F8, F9, B8, B9. 3. According to somatotypes, items which show the significant difference were, of items f3, f8, b3, b8, F2, F7, F8, B3, B7, in all movements.

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Numerical Analysis on the Internal Flow Field Characteristics of Wind Tunnel According to Contraction Type (수축부 형상에 따른 풍동 내부유동장 특성에 대한 수치해석)

  • Kim, Jang-Kweon;Oh, Seok-Hyung
    • Journal of Power System Engineering
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    • v.21 no.6
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    • pp.5-12
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    • 2017
  • The steady-state, incompressible and three-dimensional numerical analysis was carried out to investigate the internal flow fields characteristics according to wind tunnel contraction type. The turbulence model used in this study is a realizable $k-{\varepsilon}$ modified from the standard $k-{\varepsilon}$ model. As a results, the distribution of the axial mean velocity components along the central axis of the flow model is very similar to the ASME and BE types, and the cubic and cosine types. When the flow passes through the interior space of the analytical models, the flow resistance at the inlet of the plenum chamber is the largest at BS type contraction, but the smallest at cubic type contraction. The boundary layer thickness is the smallest in the cosine type contraction as the axial distance increases. The maximum turbulent kinetic energy in the test section is the smallest in the order of the contraction of cubic type and cosine type. Comprehensively, cubic type contraction is the best choice for wind tunnel performance, and cosine type contraction can be the next best solution.

Effects of Transcutaneous Electrical Nerve Stimulation(TENS), Self-Stretching and Functional Massage on the Muscle Fatigue by Maximum Muscular Strength

  • Yoon, Jung Gyu;Ryu, Je Ju;Roh, Hye Won;Yang, Hyun Ah;Lee, Sang Bin
    • Journal of International Academy of Physical Therapy Research
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    • v.3 no.2
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    • pp.422-428
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    • 2012
  • The present study purposed to examine the effects of transcutaneous electrical nerve stimulation, self-stretching and functional massage on the recovery of muscle contraction force for muscle fatigue caused by sustained isotonic contraction. The subjects of this study were 45 healthy students. They were divided into transcutaneous electrical nerve stimulation group(n=15), self-stretching group(n=15) and functional massage group(n=15), and using Primus RS. We observed the pattern of changes in maximal voluntary isometric contraction force(MVIC) after causing muscle fatigue in quadriceps femoris muscle through sustained isotonic contraction. Maximal voluntary isometric contraction force(MVIC) were greatly increased after transcutaneous electrical nerve stimulation, self-stretching and functional massage. In the comparison of recovery rate of muscle contraction force for muscle fatigue caused by sustained isotonic contraction among the treatment groups, it did not show any significant differences. However, it showed that each treatment may be effective in recovery of muscle fatigue caused by sustained isotonic contraction.

EMG Power Spectral Analysis on Masticatory Muscle Fatigue in Chronic Muscle Pain Patients (근전도 power spectrum을 이용한 만성근육동통 환자에 있어서의 저작근 피로에 관한 연구)

  • 이채훈;김영구;임형순
    • Journal of Oral Medicine and Pain
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    • v.22 no.1
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    • pp.145-155
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    • 1997
  • The purpose of this study was to compare differences in endurance time and EMG power spectral characteristics of the masticatory muscles during sustained isometric contraction between patients and controls. 15 CMD patients{8 women and 7 men, aged 15 to 38 years(24.1$\pm$7.5)}, and 15 healthy volunteers{8 women and 7 men, aged 15 to 30 years(24.7$\pm$3.4)} without past history or present symptoms of CMD were included in this study. Sustained isometric contractions of masticatory muscles were perfomeed as long as possible at 50% level of maximum voluntary contraction(MVC) of EMG activity via visual feedback, and the duration of sustained isometric contraction(endurance time) was examined. The author perfomed EMG power spectral analysis in the myoelectric signals of masseter and anterior temporal muscle during sustained isometric contraction in CMD patients with chronic muscle pain and healthy controls. The author came to following conclusions from the results. 1. The endurance time of the patient group was shorter than the control group in sustained isometric contraction of masticatory muscles(p<0.01). 2. MF values of masticatory muscles with sustained isometric contraction during endurance time were decreased following regression line in both groups(p<0.01, r>0.9). 3. The amount of MF shift to lower frequency range exhibited no significant differences between the patients and the control group in sustained isometric contraction during endurance time. 4. SMF to lower frequency range of the patient group was steeper than the control group in sustained isometric contraction during endurance time(p<0.05).

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The Study of Isometric Endurance Time by Task Type and Maximum Voluntary Contraction (작업형태 및 최대 수의적 수축에 따른 등척성 근지구력에 관한 연구)

  • Sim, Jeong-Hun;Lee, Sang-Do
    • Journal of the Ergonomics Society of Korea
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    • v.22 no.2
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    • pp.57-69
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    • 2003
  • This study was performed to investigate the isometric endurance time as percentages of maximum voluntary contraction. Electromyogram(EMG) and Borg's CR-I0 value were measured by push-pull-up-down tasks for 10 healthy males. The normalized EMG value and the MPF(mean power frequency) were used to estimate the muscle recruitment pattern and the development of muscle fatigue. The subjects exerted and maintained 5 levels of %MVC(maximum voluntary contraction) in $90^{\circ}$ shoulder flexion/ 180oelbow extension at sitting posture. The up-task showed the lower endurance time and higher Borg's CR-I0 value than the other task types. Comparing Rohmert's curve with the endurance time of task types. Rohmert's curve overestimated the endurance time of up-task and underestimated the endurance time of push-pull-down tasks. The normalized EMG value showed that muscles recruitment patterns were different from task types. The 4 muscles(biceps brachii muscle, tricep brachii muscle. middle deltoid muscle. trapezius muscle) recruitment patterns of up-task were higher than those of other tasks. The MPF value decreased with the endurance time, and the shift of MPF at up-task was larger than that of the other task types.

Effects of Muscle Fatigue through Maximum Contraction during Flexion and Extension of Knee Before and After Isometric Trunk Exercise on Elderly Hansen's Disease (한센노인의 체간운동이 슬관절 굽힘·폄 동작의 최대수축 시 근피로도에 미치는 영향)

  • Jung, Soon-Mi
    • Korean Journal of Applied Biomechanics
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    • v.21 no.1
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    • pp.115-121
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    • 2011
  • This study was to investigate the change of muscle fatigue through maximum contraction during flexion and extension of knee joint before and after the isometric trunk exercise was implemented on elderly Hansen's disease. 18 subjects exercised for 60 minutes twice a week for 12 weeks. The subjects were divided into normal sensory group, group with sensory loss in left sole, group with sensory loss in right sole, and group with sensory loss in both soles, according to the sensory condition on their soles. We obtained following results. Muscle fatigue in normal sensory group, there were significant differences in left right hamstring, left rectus femoris(p<.05), in group with sensory loss in left sole, there were significant differences in left right hamstring(p<.05), in group with sensory loss in right sole, there were significant differences in left right hamstring, right rectus femoris and group with sensory loss in both sole, there were significant differences in right hamstring(p<.05). The differences of muscle fatigue according to the sensory condition on their soles, there were significant differences in left hamstring between normal sensory group and group with sensory loss in both sole(p<.05).

Effects of Electric Stimulation and Biofeedback for Pelvic Floor Muscle Exercise in Women with Vaginal Rejuvenation Women (회음부 성형수술 여성에서 전기자극과 바이오피드백을 이용한 골반저근운동의 효과)

  • Lee, Jung Bok;Choi, So Young
    • Journal of Korean Academy of Nursing
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    • v.45 no.5
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    • pp.713-722
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    • 2015
  • Purpose: The purpose of this study was to investigate the effects of pelvic floor muscle exercise using electric stimulation and biofeedback on maximum pressure of vaginal contraction, vaginal contraction duration and sexual function in women who have had vaginal rejuvenation. Methods: The research design was a non-equivalent control group non-synchronized design study. Participants in this study were women who had vaginal rejuvenation at C obstetrics and gynecology hospital. The 15 participants in the experimental group were given pelvic floor muscle exercise using electric stimulation and biofeedback and the 15 participants in the control group received self pelvic floor muscle exercise. Results: For maximum pressure of vaginal contraction, the experimental group showed a statistically significant increase compared to than the control group (t=5.96, p <.001). For vaginal contraction duration, the experimental group also showed a statistically significant increase compared to the control group (t=3.23, p =.003). For women' s sexual function, the experimental group showed a significant increase when compared to the control group in total sexual function scores (t=3.41, p =.002). Conclusion: The results indicate that pelvic floor muscle exercise with electric stimulation and biofeedback after vaginal rejuvenation is effective in strengthening vaginal contraction pressure, vaginal contraction and that it also positively functions to increase women's sexual function.

Vasodilatory Effect of the Alkaloid Component from the Roots of Cynanchum wifordi Hemsley (백하수오 알칼로이드 성분의 혈관이안 효능)

  • 장기철;이동웅
    • Journal of Life Science
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    • v.10 no.6
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    • pp.584-590
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    • 2000
  • Natural products are one of the useful source of cardiovascular drugs, in particular, when they have antioxidant activity. Gagaminine, an alkaloid isolated from the roots of Cynanchum wilfordi Hemsley, has been reported to potently inhibit the aldehyde oxidase activity ({TEX}$IC_{50}${/TEX}=0.8$\mu$M) and reduce lipid peroxidation. However, the effect of gagaminine on vascular smooth muscle has not yet been investigated. In the present study, we examined whether gagaminine relaxes vascular smooth muscle by isometric tension study. In order to observe its relaxation effect on the arteries, conductivel vessel (rat thoracic aorta) and resistance vessel (pig coronary artery) were purposely used. Results indicated that gagaminine relaxed in a concentration-dependent manner $\alpha$-adrenoceptor agonist, phenylephrine (PE)-induced contraction of rat aorta. Pretreatment with gagaminine inhibited PE-induced contraction, noncompetitively. {TEX}$Ca^{2+}${/TEX}-induced contraction was significantly diminished by gagaminine. In pig coronary artery, gagaminine relaxed thromboxane receptor (U 46619)-mediated contraction in dose-dependent manner. Pretreatment with gagaminine also reduced the maximum contraction induced by KCl. These observations strongly suggest that agagminnine relaxes vascular smooth muscle, irrespective of both resistance and conductive artery. We demonstrate that gagaminine, a potent natural antioxidant, has a significant vasodilatory effect and its action mechanism van be ascribed at least in part to {TEX}$Ca^{2+}${/TEX} antagonistic action as evidenced by inhibition {TEX}$Ca^{2+}${/TEX}-induced contraction (rat aorta) and KCl-induced contraction (porcine artery). Furthermore, neither $\alpha$ -adrenoceptor nor thromboxane receptor seems responsible for the relaxation of gagaminine.

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Contractile Mechanisms of Serotonin in the Renal Arterial smooth muscle of a Rabbit (Serotonin에 의한 가토 신동맥 평활근 수축기전)

  • Lee, Woo-Young;Kim, Se-Hoon;Chang, Seok-Jong
    • The Korean Journal of Physiology
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    • v.24 no.1
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    • pp.67-76
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    • 1990
  • The contractile mechanisms of serotonin were investigated in the renal artery of a rabbit. The helical strips of isolated renal artery were immersed in the normal or $Ca^{2+}$-free tris-buffered Tyrode's solution, which was equilibrated with 100% $O_{2}$ at $35^{\circ}C$. The contraction by serotonin or norepinephrine (NE) began at $1{\times}10^{-7}\;M$ and reached the maximal contraction at $1{\times}10^{-5}\;M$. The maximal contraction by serotonin corresponded to $58.1{\pm}4.2%$ of maximal contraction by NE. Cyproheptadine, a serotonin receptor blocker, shifted the concentration-response curve to the right without any reduction in the maximum response but shifted that of NE to the right with reduction in maximum response. And phentolamine, an ${\alpha}-receptor$ blocker, shifted the concentration-response curve of serotonin or NE without any reduction in maximum responses. The $pA_{2}$ values for cyproheptadine against serotonin and NE were $10.35{\pm}0.04$ and $8.45{\pm}0.13$, respectively. The $pA_{2}$ values for phentolamine against serotonin and NE were $6.87{\pm}0.04$ and $8.14{\pm}0.08$, respectively. after the pretreatment with 6-hydroxydopamine, the contraction induced by 100 mM $K^{+}$, tyramine and serotonin reduced to $83.0{\pm}2.0$, $26.8{\pm}6.2$ and $82.0{\pm}3.5%$ of control, respectively. The contraction by serotonin in the $Ca^{2+}$-free Tyrode's solution was increased and sustained with the addition of $Ca^{2+}$ extracellulary. The serotonin-sensitive intracellular $Ca^{2+}$ pool was depleted completely by the pretreatment with NE, but the NE-sensitive intracellular $Ca^{2+}$ pool was depleted partially by the pretreatment with serotonin. From the above results, it is suggested that the contraction induced by serotonin in the renal artery of a rabbit may be due to mechanisms in which serotonin acts directly on specific serotonin receptors and also acts indirectly on ${\alpha}-adrenoceptors$ by displacing NE from neuronal stores.

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The Effect of Pelvic Muscle Exercise Program on Women with Stress Urinary Incontinence in the Degree and Amount of Urinary Incontinence and Maximum Vaginal Contraction Pressure (골반저근육 운동 프로그램이 긴장성 요실금 여성의 요실금정도, 요실금량 및 최대 질수축압에 미치는 영향)

  • Kim, So Young;Park, Jeong Sook
    • Korean Journal of Adult Nursing
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    • v.12 no.2
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    • pp.267-277
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    • 2000
  • The purpose of this study was to help the women with stress urinary incontinence lead more comfortable life, by letting them to do pelvic muscle exercise and to learn by direct experience the effect that urinary incontinence is controlled. The research design was a one-group pretest-posttest design. The subjects were 16 middle-aged women(over 38) with stress urinary incontinence. The study was conducted from August 1, to October 11, 1999. Women trained themselves for muscular strength and endurance, every the other day for each exercise for six weeks at home(that means each exercise for more than three days a week) in the pelvic muscle exercise program which was developed by Dougherty et al., and filled out exercise participation card every week. They visited laboratory once a week to get visual feedback, by means of Perineometer, of how the pelvic muscle exercise was going on. Stress Urinary Incontinence Scale that Lee, Young-Sook revised and supplemented Hendrickson's original scale was used for measuring the frequency and situation scores of urinary incontinence, "30 minute pad test" was carried out for measuring the amount of urinary incontinence, and Perineometer was used for measuring maximum vaginal contraction pressure. Percentage, mean, standard deviation and Wilcoxon signed ranks test were used for data analysis by means of SPSS/PC+ WIN 9.0 program. The results were summarized as follows : The hypothesis 1 that after carrying out pelvic muscle exercise program on women with stress urinary incontinence, the weekly degree of urinary incontinence would reduce compared to before the exercise was supported. The hypothesis 1-1 that after carrying out pelvic muscle exercise program on women with stress urinary incontinence, the weekly frequency of urinary incontinence would reduce compared to before the exercise was supported (p=.003). The hypothesis 1-2 that after carrying out pelvic muscle exercise program on women with stress urinary incontinence, the situation scores of urinary incontinence would reduce compared to before the exercise was supported(p=.044). The hypothesis 2 that after carrying out pelvic muscle exercise program on women with stress urinary incontinence, the amount of urinary incontinence would reduce compared to before the exercise was supported(p=.001). The hypothesis 3 that after carrying out pelvic muscle exercise program on women with stress urinary incontinence, the maximum vaginal contraction pressure would increase compared to before the exercise was supported (p=.012). These results suggest that pelvic muscle exercise program has an effect on women with stress urinary incontinence in the degree and amount of urinary incontinence and maximum vaginal contraction pressure. So it is judged that training women with stress urinary incontinence for pelvic muscle exercise is an effective nursing intervention strategy in order to care urinary incontinence.

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