Browse > Article
http://dx.doi.org/10.5143/JESK.2010.29.3.279

Comparison Between Right and Left Muscle Activities of Hip and Trunk During Manual Task in Asymmetric Weight-Bearing Posture  

Choung, Ji-Yun (Department of Physical Therapy, Jaseng Hospital of Oriental Medicine)
Jeon, Hye-Seon (Department of Ergonomic Therapy The Graduate School of Health and Environment, Yonsei University)
Lee, Chung-Hwi (Department of Ergonomic Therapy The Graduate School of Health and Environment, Yonsei University)
Lee, Jeon-Won (Department of Occupational Therapy Yeojoo Institute of Technology)
Publication Information
Journal of the Ergonomics Society of Korea / v.29, no.3, 2010 , pp. 279-286 More about this Journal
Abstract
The purpose of this study was to compare the electromyographic(EMG) activities of trunk and hip muscles between right and left sides while subjects performed prolonged manual task in asymmetric and symmetric weight-bearing posture. Fifteen healthy male college students were recruited for this study. The subjects were asked to perform bimanual upper extremity task for 6 minutes in two different standing postures. In the symmetric weight-bearing posture, the subjects were standing with evenly distributed body weights to both legs. In the asymmetric weight-bearing posture, the subjects distributed about 90% of their body weight onto their preferred(supporting) leg and 10% of their body weight onto the opposite leg while they were standing. EMG activities of the right and left internal oblique, erector spinae, gluteus maximus, and gluteus medius were measured and normalized as % MVIC. Then the EMG data were statistically analyzed using paired t-tests. The EMG activities of all measured muscles were not significantly different between the right and left side in the symmetrical weight-bearing posture(p>0.05). However, the EMG of the supporting side internal oblique was significantly lower than the opposite side(p<0.05), and the EMG of the erector spinae, gluteus maximus, and gluteus medius were significantly greater on the supporting side(p<0.05). The results of this study support that unbalanced use of right and left muscle possibly causes the changes in muscle length which results in asymmetry of trunk and hip muscles. Furthermore, the uneven weight support onto right and left legs will cause a distortion of viscoelastic ligaments around hip and sacroiliac joints in the long run. Further studies to determine the effect of various manual tasks on the trunk and hip muscles as well as the effect of asymmetrical weight-bearing standing posture on hip and back muscle fatigue may be required.
Keywords
Manual task; Muscle activities; Weight bearing;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Grandjean, E. and Hunting, W., Ergonomics of posture review of various problem of standing and sitting postures, Applied Ergonomics, 8(3), 135-140, 1977.   DOI
2 Granata, K. P. and Wilson, S. E., Trunk posture and spinal stability, Clinical Biomechanics, 16(8), 650-659, 2001.   DOI
3 Kirbly, R. L. and Price, N. A. and MacLeod, D. A., The influence of foot position on standing balance, Journal of Biomechanics, 20(4), 423-442, 1987.   DOI
4 김현욱, 우리나라에서 근골격계 질환의 발생 현황 및 증가 요인, 한국산업의학, 41(4), 155-163, 2002.
5 김해진, 근육 피로도 측면에서의 입식 작업과 좌식 작업 비교, 충북대학교 석사학위 논문. 2000.
6 노동부, 근골격계 부담작업 범위, 노동부 고시 제 2003-24호, 2003.
7 노동부, 산업재해 현황 분석, 2007.
8 Kothiyal, K. and Kaysis, B., Workplace layout for seated manual handling tasks; an electromyography study, Journal of Ergonomics, 27(1), 19-32, 2001.   DOI
9 Souza, G. M., Baker, L. L. and Powers, C. M., Electromyographic activity of selected trunk muscles during spine stabilization exercises, Archives of Physical Medicine Rehabilitation, 82(11), 1551-1557, 2001.   DOI
10 Winkle, J., Evaluation of foot swelling and lower-limb temperatures in relation to leg activity during long-term seated office work, Ergonomics, 29(2), 313-328, 1986.   DOI
11 Luoto, S., Aalto, H., Taimela, S., Hurri, H., Pyykko, I. and Alaranta, H., Onefooted and externally disturbed two footed posture control in patients with chronic low back pain and healthy control subjects, A controlled study with follow up, Spine, 23(19), 2081-2089, 1998.   DOI
12 Madeleine. P., Lundager, B., Voigt, M. and Arendt-Nielsen, L., Sensory manifestations in experimental and work-related chronic neck-shoulder pain, Euroopean Journal of Pain, 2, 251-260, 1998.   DOI
13 NIOSH., Musculoskeletal Disorders and Workplace Factors., US. Department of Health and Human Service Center for Disease Control and Prevention, 1997.
14 Neumann, D. A, Kinesiology of the musculoskeletal system. St. Louis: Mosby, 2002.
15 Panjabi, M. M., Clinical spinal instability and low back pain, Journal of Electromyography and Kinesiol, 13(4), 371-379, 2003.   DOI
16 P. van Wely., Design and disease, Appl Ergon, 1(5), 262-269, 1970.   DOI
17 Richardson, C. A., Snijders, C. J., Hides, J. A., Damen, L., Pas, M. S. and Storm., The relationship between the transversely oriented abdominal muscles, sacroiliac joint mechanics and low back pain, Spine, 27, 399-405, 2002.   DOI
18 배지혜, 나진경, 유지연, 박영옥, 요통 환자의 다열근 위축에 대한 관찰, 대한재활의학회지, 25(4), 684-691, 2001.
19 Ryan, G. A., The prevalence of musculo-skeletal symptoms in supermarket workers, Ergonomics, 32(4), 359-371, 1989.   DOI
20 Snijders, C. J., Ribbers, M. T. L. M., de Bakker, J. V., Stoeckart, R. and Stam, H. J., EMG recording of abdominal and back muscles in various standing postures, validation of a biomechanical model on sacroiliac joint stability, Journal of Electromyography and Kinesiology, 8, 205-214, 1998.   DOI
21 산업안전공단. 근골격계 예방지침, 2006.
22 임창준, 모 전자 사업장 작업자들의 작업 관련성 근골격계 질환 자각증상과 작업특성에 관한 연구, 홍익대학교 석사학위 논문. 2003.
23 정연길, 컴퓨터 작업 시 다리 꼬기가 체간 근육의 근활성도에 미치는 효과, 연세대학교 석사학위논문. 2005.
24 Bergmark A., Stability of the lumbar spine. A study in mechanical engeering, Acta Orthop Scand Suppl, 23(6), 20-24, 1989.
25 Phyllis, M. K., A comparison of the effects of floor mats and shoe in-soles on standing fatigue, Applied Ergonomics, 33(5), 477-478. 2002.   DOI
26 Chen, W. P., Tai, C. L., Tan, C. F., Sin, C. H., Hou, S. H. and M. S., The degrees to which transtrochanteric rotational osteotomy moves the region of osteonecrotic femoral head out of the weight-bearing areas as evaluated by computer simulation, Clinical Biomechanics, 20, 63-69, 2005.   DOI
27 Cram, J. R., Kasman, G. S. and Holtz J., Introduction to surface electromyography. Gaithersburg: Aspen Publisher. 1998.
28 Genthon, N. and Rougier, P., Influence of an asymmetrical body weight distribution on the control of undisturbed upright stance, Journal of Applied Biomechanics, 38, 2037-2049, 2004.