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J Korean Soc Phys Med, 2014; 9(2): 233-242 http://dx.doi.org/10.13066/kspm.2014.9.2.233 Online ISSN: 2287-7215 Print ISSN: 1975-311X Research Article Open Access 고관절내전근수축을이용한교각운동이복부근육의두께에미치는영향 이건철 배원식 김지혁경남정보대학교물리치료과 The Effects of Bridge Exercise with Contraction of Hip Adductor Muscles on Thickness of Abdominal Muscles Geon-Cheol Lee, PT, PhD, Won-Sik Bae, PT, MPH, Chi-Hyok Kim, PT, MPH Department of Physical Therapy, Kyungnam College of Information & Technology Received: April 19, 2014 / Revised: May 22, 2014 / Accepted: May 27, 2014 c 2014 J Korean Soc Phys Med Abstract 1 PURPOSE: The purpose of this study was to determine the correlation between the hip adductor muscles and abdominal muscles during bridge exercise. METHOD: Participants who met the criteria for this study(n=36) were divided into the three groups. The first experimental group performed normal bridge exercises and the second group performed bridge exercises with the contraction of the hip adductor muscles and the control group didn t perform any exercise. Transversus abdominis muscle thickness was measured by ultrasound imaging with a special transducer head device, at pre exercise, after 2 weeks, 4 weeks, and 6 weeks. RESULT: Data were analyzed using repeated ANOVA with the level of significance set at =.05. Transversus abdominis muscle thickness was influenced by contraction of the hip adductor muscles during bridge exercise in people without lower back pain. Compared with normal bridge exercise, transversus abdominis muscle thickness significantly increased in thickness during bridge exercise with contraction of the hip adductor muscles(p<.05). CONCLUSION: The results from this study showed that contraction of the hip adductor muscles during bridge exercise increased change in the transversus abdominis muscle thickness. These results can be a good source to prevent low back pain due to hip adductor weakness. Therefore, inducing activation of hip adductor with abdominal stabilizing exercise is more effective in patients with low back pain. Key Words: Bridging exercise, Hip adductor, Transversus abdominis Corresponding Author : f452000@nate.com This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Ⅰ. 서론요통의중요한원인중의하나는요추부 (lumbar segment) 의불안정성이다 (Hodges와 Moseley, 2003). 요추손상의예방과치료에중요한척추의안정성은체간

234 대한물리의학회지제 9 권제 2 호 근육의동시활동으로이루어진다 (O'Sullivan, 2000). 이러한척추안정성을유지하기위하여임상에서많이사용되고있는것이체간안정화운동이다 (Kim과 Kwon, 2001; Kim 등, 2006; Akuthota와 Nadler, 2004; Marshall과 Murphy, 2005). 복근활성화를위한운동요법으로최근에는척추분절의불안정성에치료의초점을맞추어척추분절조절과안정화제공에중요한역할을하는것으로여겨지는요통의새로운운동치료법으로요부안정화운동이복근강화에적용되고있다 (Ha 등, 2013). 안정화운동은환자의자세가불안정할때힘을조절할수있도록하는것과척추가외부부하에가장잘적용할수있는자세인척추중립자세를유지할수있도록의식적, 무의식적으로움직임을조절할수있도록시행하는운동이며, 치료적운동과더불어예방적차원의관리측면에서도주목받고있다 (Magee, 1999). Lehman 등 (2005) 은저강도의체간근육활동을필요로하는재활운동에서는체간안정화운동이중요하다고설명하면서, 교각운동의필요성을강조하였다. 교각운동은요추에가해지는외력을흡수하고, 사지의움직임동안주위근육들의협응작용과상호보완작용이이루어지도록하여척추주변조직들에가해지는반복적인손상을예방하기위하여시행되는운동이다 (Jeon, 2010). 이는체간근육이나골반저근육자체에중점을두고있는운동방법이며체간을안정화시키고하지와둔부의근력을증진시키려는운동으로써임상에서자주이용되어진다 (Kisner와 Colby, 2007). 따라서교각운동은선행연구들에서이미다양한방법으로수정되어적용되었다. Kim 등 (2010) 은교각운동시슬관절의각도 (120, 90, 60, 45 ) 에따라근활성도가다르게나타나는데그중복부근육의최대근활성도를보인것은 120 라고하였다. 중심안정성과관련된척주근육은대근육 (global muscle) 과소근육 (local muscle) 으로구분된다. 다분절성근육즉, 외복사근, 복직근, 척주주위근을포함하는대근육은몸에가해지는중력이나무거운물건을들어올리는것과같은외적부하에대해균형을유지하는근육들이다. 반면, 소근육은극간근, 횡돌간근, 내복사 근, 다열근이포함되며척추의만곡을유지하며, 척추전ㆍ후방및측방의안정성을유지하는데중요한역할을하는근육들이다 (Akuthota와 Nadler, 2004; Bergmark, 1989). 고관절내전근은건강한성인의대퇴에서약 25% 의부피를차지하고있다 (Akima 등, 2007). 내전근의수축은복부근과골반저근육의수축을촉진시키고, 이러한내전근과복부근육, 골반저근육의동시수축은복부내압의생산에필수적이며, 이는요추부에걸리는부하를줄여줌으로써척추의안정성을위한다열근의기능을강화시키는작용을한다 (Hemborg 등, 1983; Cholewicki 등, 1997). 이러한대근육, 소근육과더불어고관절신전근, 내ㆍ외전근, 견갑골안정근등이상지와하지를체간에연결해주는골격근들로서사용되고있다 (Cresswell 과 Thorstensson, 1994). Kim과 Yoo(2011) 는실제로근위부구조물들의안정성이효과적인원위부구조물의움직임이나자세를위해필수적인것으로, 체간과고관절의관계는매우중요하다고하였고 Moon과 Koo(2011) 는고관절내전근의단독수축이복횡근의두께를증가시킨다고하였다. 또한 Na 등 (2012) 은근전도를이용하여젊은성인의교각운동시고관절내전근을동시수축하였을때체간근육의활성도가높아진다고하였다. Bae와 Kim(2013) 또한교각운동시초음파를이용하여측정한결과복횡근의두께를증가시킨다고하였다. 일반적인체간안정화와관련된다양한운동에있어교각운동에서의효과들은여러논문에서밝힌바있지만고관절의내전수축을동반하여교각운동시복부근육의두께에미치는영향에대한연구는아직진행되지않았다. 최근요부안정화연구에초음파를이용한근골격계검사가자주사용되고있다 (Ainscouph-Potts 등, 2006; Hodges와 Moseley, 2003; Bae와 Kim, 2013). 초음파검사는비침습적 (non-invasive) 인측정방법으로침근전도와비교해서통증이없고 (Kim 등, 1999), MRI와 CT보다저비용이며 (Peetrons, 2002), 움직임이나자세에따른관절변화와근육의실시간관찰도용이하기때문이다 (Ko 등, 2008). 또한근육의근전도와초음파상두께

고관절내전근수축을이용한교각운동이복부근육의두께에미치는영향 235 변화를비교한연구결과유의한상관성을보여근수축의척도로사용할수있다 (Hodges와 Moseley, 2003; McMeeken 등, 2004). 따라서본연구는고관절내전근수축을이용한교각운동이척추의안정성을증진시킬수있을것이라는가설아래척추의안정성에기여하는복부근육중복횡근, 복직근, 내ㆍ외복사근을초음파로측정하여그근육의두께변화를알아보고이를통하여체간안정화를위한교각운동시좀더효과적인방법을제시하고자하였다. 체피드백기구 (stabilizer, chattanooga group Inc., Hixson, U.S.A) 를사용하였다 (Fig 1). 2) 초음파영상진단장치실험대상자에대한운동전ㆍ후 4가지복근의두께를측정하기위하여진단용초음파측정기구 (My lab one World. Esaote. Italy) 를사용하였으며근육및표층전용으로직선형태의탐촉자를사용하였다 (Fig 2). Ⅱ. 연구방법 1. 연구의대상및기간본연구의대상자는실험의내용을이해하고동의하며, 이에요구되는운동을수행할수있는부산 K대학의건강한 20대성인 36명 ( 남자 18명, 여자 18명 ) 을대상으로 2013년 4월 2일부터 5월 13일까지 6주간주 3회운동을실시하였다. 이전에체간과하지에근골격계이상이있는자및수술적요법을받은자는제외하였다. 2. 실험도구 1) 압력생체피드백기구내전근의수축을일으킨상태에서의교각운동시무릎내측사이에균등한압력을유지하기위해압력생 Fig 1. Pressure Biofeedback Unit Fig 2. Ultrasound device for diagnosis and probe shape 3. 연구방법교각운동을실시하는동안고관절내전근의수축이복부근육의두께에미치는영향을알아보기위하여내전근의수축을일으킨상태에서의교각운동 (A 그룹, Fig 3) 과, 일반교각운동 (B 그룹, Fig 4) 그리고아무런운동을하지않은대조군그룹 (C 그룹 ) 을비교하였다. 내전근의수축을일으킨상태에서의교각운동시무릎내측사이에압력생체피드백기구 (pressure bio feedback unit) 를끼워장치가다리에힘을주지않아도바닥에떨어지지않을정도의압력인 20 mmhg로높였다. 그상태에서실험대상자에게현재압력을보여준후 60 mmhg만큼압력이올라가도록양무릎내측으로압력계를누르라고지시하였다. 모든실험은 10회반복 3세

236 대한물리의학회지제 9 권제 2 호 트로운동하였으며, 각각의조건에서 10 초간유지하도 록하였다. 운동시근육의피로를방지하기위하여 각세트별운동후 30 초간의휴식을취하였다. Fig 5. RA thickness photographing image Fig 3. Bridging Exercise with Adductor Contraction Fig 4. Bridging Exercise Fig 6. IO, EO, TrA thickness photographing image 4. 측정방법고관절내전근수축을이용한교각운동시복부근육의두께에미치는영향을알아보기위하여실험전, 운동 2주후, 4주후, 6주후총 3번의변화정도를초음파로측정하였다 (Fig 5, 6). 측정자는연구대상자의좌측에서복직근 ( 배꼽상부 3 cm), 내ㆍ외복사근및복횡근 ( 전상장골능과치골결합부위중간부분서혜인대바로위쪽 / 배꼽외측 15 cm) 의근섬유와평행한방향으로측정하였다 (Critchley, 2002; Mcmeeken 등, 2004). 모든측정은한명의숙련된검사자가측정하였다. 5. 분석방법자료의통계처리는전ㆍ후의차이를알아보기위해서반복측정분산분석을사용하였고, 통계처리는 IBM SPSS Statistics version 21 프로그램을사용하였으며유의수준은 α=.05로하였다. Ⅲ. 연구결과 1. 연구대상자의일반적특성본연구에참여한대상자들의일반적인특성은 Table 1과같다. 20대성인남자 18명, 여자 18명총

고관절내전근수축을이용한교각운동이복부근육의두께에미치는영향 237 Table 1. The general characteristics of subjects (N=36) Sex Age(y) Height(cm) Weight(kg) Male 22.39±2.73ª 174.58±4.70 67.88±8.02 Female 20.94±1.06 162.17±4.55 55.15±5.54 ª mean±standard deviation 36명으로평균신장은남자 174.58±4.70cm, 여자 162.17±4.55cm, 평균몸무게는남자 67.88±8.02kg, 여자 55.15±5.54kg으로나타났다. 2. 교각운동시내전근수축유ㆍ무에따른근두께의변화 6주간의교각운동에따른각그룹별근육의변화를반복측정분산분석으로분석하였으며차이는 Table 2 와같다. 외복사근은 Mauchly의구형성검정에서통계학적으로유의하였으며다변량검정결과훈련기간에따른실험군 A, 실험군 B, 대조군의집단내외복사근두께변화량비교에있어서통계학적으로유의한차이가없었고또한훈련기간과훈련방법의상호작용은통계학적으로유의한차이가없었다. 그룹에따른개체-간 효과검정을비교해본결과통계학적으로유의한차이가없었다. 6주간의교각운동에따른각그룹별내복사근의변화는 Table 2와같다. Mauchly의구형성검정에서통계학적으로유의하였으며다변량검정결과훈련기간에따른실험군 A, 실험군 B, 대조군의집단내내복사근두께변화량비교에있어서통계학적으로유의한차이가없었고또한훈련기간과훈련방법의상호작용은통계학적유의한차이가없었다. 그룹에따른개체-간효과검정을비교해본결과통계학적으로유의한차이가없었다. 6주간의교각운동에따른각그룹별복횡근의변화는 Table 2와같다. Mauchly의구형성검정에서통계학적으로유의하였으며다변량검정결과훈련기간에따라복횡근두께변화량비교에있어서통계학적으로 Table 2. Comparison of abdominal thickness among three groups (unit: mm) Variable Group 1 2 3 4 F p EO IO TrA RA Exp A 5.36±1.30 4.94±0.95 5.03±0.96 5.27±1.20 Exp B 5.05±1.12 4.76±1.11 5.11±1.33 5.33±1.20 Control 5.01±1.11 5.09±1.19 5.28±1.09 5.47±1.58 Exp A 8.12±1.68 7.99±2.03 7.82±1.70 8.28±1.66 Exp B 8.20±2.23 8.31±2.88 8.29±2.53 8.41±2.68 Control 8.46±2.87 7.27±1.93 7.87±1.74 7.85±1.93 Exp A 3.36±0.80 4.26±0.90 4.70±0.84 5.07±0.88 Exp B 3.47±0.82 4.11±1.34 4.55±0.91 4.67±0.94 Control 3.45±1.21 3.17±079 3.22±0.59 3.36±0.71 Exp A 10.93±2.75 10.15±2.25 10.60±2.34 10.36±2.06 Exp B 10.51±2.84 10.59±2.68 10.81±3.27 10.55±2.56 Control 10.15±2.34 10.79±2.01 10.88±2.68 10.84±2.67 M±SD ** p<.01 EO : External oblique IO : Internal oblique TrA : Transverse abdominis RA : Rectus abdominis Exp A : Bridging Exercise with Adductor Contraction Exp B : Bridging Exercise.06.94.15.86 6.42.00**.01.99

238 대한물리의학회지제 9 권제 2 호 Fig 7. Comparison of the TrA Thickness at 6 weeks follow-up test among three groups 유의한차이가있었고 (p<.001)(fig 7), 또한훈련기간과실험군에따라상호작용이있었다 (p<.01). 상호작용요인확인결과실험군 A와실험군 B는측정시기증가시복횡근의두께가증가하였지만대조군은측정시기증가시두께가변화없음을알수있었다. 그룹에따른개체- 간효과검정을비교해본결과통계학적으로유의한차이가있었다 (p<.05). 훈련형태에따른차이를알아보기위해 Scheffe 사후검정을실시한결과실험군 A와대조군간에유의한차이를보였다. 6주간의교각운동에따른각그룹별복직근의변화는 Table 2와같다. Mauchly의구형성검정에서통계학적으로유의하였으며다변량검정결과훈련기간에따른실험군 A, 실험군 B, 대조군의집단내복직근두께변화량비교에있어서통계학적으로유의한차이가없 었고훈련기간과훈련방법의상호작용또한통계학적으로유의한차이가없었다. 그룹에따른개체- 간효과검정을비교해본결과통계학적으로유의한차이가없었다. Ⅳ. 고찰본연구는체간안정화운동의가장일반적인교각운동자세에서복부근육의수축을위해가장좋은조건을찾기위한방법중하나로고관절내전근수축방법을사용하여복부에미치는영향을알아보기위하여근두께를측정하여복부근육과의상관성을분석하였다.

고관절내전근수축을이용한교각운동이복부근육의두께에미치는영향 239 내전근의등척성수축을이용한교각운동은일반교각운동과비교하여볼때, 복횡근, 복직근과같은체간근육과많은상관성을보이는것으로나타났다 (Moon과 Koo, 2011). Kisner와 Colby(2007) 는복횡근은복부압력증가및안정성에가장크게영향을미치는근육이며, 교각운동은복횡근의수축을유발하는자세에서실시하는것이가장좋은방법이라고하였다. Moon과 Koo(2011) 는고관절내전근수축이복횡근의두께변화에미치는영향에대한연구에서, 선자세에서의하지움직임시에복부근활성도측정결과내전근수축전 (4.15±1.04) 에비해수축후 (6.00±1.88) 복횡근의두께가유의하게증가함을보고하였다. 또한 Hodges와 Richardson(1997) 은하지의움직임시요부에있는심부근육들이선행적자세조절을함으로써하지의움직임이일어나기전에고관절과척추사이의기능적관계를원활히하도록체간의안정영역으로서작용을하며특징적으로상지에비하여하지에서는하지의움직임방향에따라심복부근의활성도가달라진다고하였다. Lee(2012) 는일반적인교각운동시복부및하지근육과는음의상관관계를, 내전근을수축시키는교각운동에서는양의상관관계를, 외전근을수축시키는교각운동에서는양의상관관계를보인다고하였다. 이와같은선행연구는내전근의수축을통한교각운동이더욱효과적인복압증가와골반안정성훈련으로적당하다는본연구를뒷받침하였다. Kavcic 등 (2004) 은건강한성인에서요부안정화운동을수행하는동안근육의부하량과척추의안정화에대한연구에서교각운동이복직근의근활성도와매우높은연관성이있다고하였고단순교각운동으로도표층근육군을활성화시킨다고보고하였지만, 본연구에서는실험군 B에서복직근의두께변화에있어서는유의한차이가없어서상반되는결과를보였다. 따라서본연구에서는내전근수축을동반한교각운동을적용하였을때복부의근두께변화여부를알아보기위하여연구를진행하였고연구결과내전근수축을동반한교각운동을적용하였을때체간근육중복횡근의두께가유의하게증가됨을알수있었다. 하지만다른심부근육인내복사근의두께와표층근육인복직 근, 외복사근의두께변화는통계적으로유의한차이를보이지않았다. 이상의결과에서하지내전근수축을동반한교각운동이심부근육을선택적으로활성화시키고있음을확인할수있었다. 이러한결과에대한역학적배경으로고관절내전근들은하지를내전시키는기능뿐만아니라굴곡, 신전, 회전및고관절안정성에도기여한다. 고관절내전시요골반부와척추의근육이동시수축하고특히복횡근과다열근이선행수축하면서장골능에정지하고있는복횡근은장골을척추쪽을향하여횡방향으로당기는첫번째힘이발생한다. 그로인해천장관절에붙어있는인대들이강한인장력에대한반작용으로더큰수축을하게되면서두번째힘이생기게된다. 이두합력의벡터는장골이천골을꽉조이게만드는방향이되어천장관절의불안정성이감소하게되면서척추를바르게정렬시키고, 정렬된척추는요통의원인이되는구조적불안정성을보완해주게되는것이다 (Hoek van Dijke 등, 1999). 이와같은해부학적위치는골반에부착되어지는체간근의조절과도관계가있다. 척추의안정성에기여하는복횡근과다열근이사지의움직임시작시선행적자세조절로서작용하여사지의위치에따라체간에서무게중심을조절하는역할을하는것이다. 이러한원리를이용해사지에저항을주거나움직임을줌으로서척추의올바른정렬을만들기위한전략으로요골반부에서신경근협응이일어나게되는데, 그것은요부의안정성을증진시키는데적용할수도있다 (Weinstein 등, 1998). 또한요천추및대퇴부가같은신경지배영역에있기때문에상지에비하여하지의움직임시복횡근에서수축이더많이일어난다는선행연구들이있었다 (Hodges와 Richardson, 1997). Na 등 (2012) 은젊은성인의교각운동시내전근동시수축이체간근육의각활성도에미치는영향을알아본결과내전근동시수축유ㆍ무에따라내복사근과복직근의근활성도는유의하게증가되었으나다열근과척추기립근의근활성도에서는유의한차이가보이지않았다고하였다. 또한교각운동시내전근동시수축유무에따른복부와배부의대근육에대한소근육의비를알아본결과복부에서이비가유의하게증가되는것으

240 대한물리의학회지제 9 권제 2 호 로나타났는데, 이는교각운동시내전근동시수축이대근육에비해소근육의근활성도가높아지는것을의미한다고하였다. Barnett과 Gilleard(2005) 는여러가지운동방법동안대근육과소근육의활성도비를비교한연구에서소근육의활성도가높은심복부운동이체간안정화에더효과적이라고하였다. 또한 Arokoski 등 (2004) 은요추부안정화를위하여소근육활성도비가중요하다고강조하였다. 이는교각운동시내전근을동시수축시키는방법이요추부안정화를위해더효과적인것으로여겨질수있다. 본연구는건강한 20대정상성인을대상으로하여인간을대상으로하는일반성의결과를제시하지못한다는점에서제한점이있으므로다양한연령대의더많은대상자들을바탕으로추가적인연구가이루어져야할것이며, 초음파이외에근전도를추가한연구를통해근전도의근활성도와초음파의근육두께를측정하는방법들사이의상관관계를구하는연구가필요하리라고사료된다. 복횡근은체간의모든빠른동작을수행할경우수축을일으키고체간의움직임을일으키는근육들보다먼저수축을한다. Hodges와 Richardson(1997) 은요통증상이없는사람들이상지와하지를빠르게움직이도록하였을때복횡근이먼저수축을일으켰으며, 요통환자들의경우에는상지와하지를움직일때복횡근이가장먼저수축하지않았다고하였다. 따라서체간안정성을필요로하는요통환자군을대상으로한추가적인연구가필요할것으로여겨진다. Ⅴ. 결론본연구는건강한 20대성인 36명 ( 남자 18명, 여자 18명 ) 을대상으로고관절내전근수축을이용한교각운동이복부근육의두께에미치는영향을알아보고자하였으며그결과대퇴내전근수축에따라요부의안정성에대표적으로관여하는복횡근의두께가두꺼워지는것을알수있었다. 일반적으로근육의두께 ( 횡단면적 ) 가커짐은근원 섬유수가늘어나수축력이증대되면서모세혈관의분포도가많아지는것으로볼때, 하지의내전근동시수축시에심부복근의두께가두꺼워지면서요부의안정화도증가될수있을것이다. 따라서교각운동과같은복부안정성운동을실시할때, 내전근의활성을유도하여실시하는것이더욱효과적일것이다. References Ainscouph-Potts AM, Morrissey MC, Critchley D. The response of the transverse abdominis and internal oblique muscles to different postures. Man Ther. 2006;11(1): 54-60. Akima H, Ushiyama JI, Kudo J et al. Effect of unloading on muscle volume with and without resistance training. Acta Astronaut. 2007;60(8-9):728-36. Akuthoma V, Nadler SF. Core strengthening. Arch Phys Med Rehabil. 2004;85(3 Suppl 1):86-92. Arokoski JP, Valta T, Kankaanpaa M et al. Activation of lumbar paraspinal and abdominal muscles during therapeutic exercises in chronic low back pain patients. Arch Phys Med Rehabil. 2004;85(5):823-32. Bae WS, Kim CH. The effect of closed kinetic and open kinetic exercise on thickness of low back stabilization exercise using an ultrasonography imaging. J Kor Soc Integr Med. 2013;1(2):67-80. Barnett F, Gilleard W. The use of lumbar spinal stabilization techniques during the performance of abdominal strengthening exercise variations. J Sports Med Phys Fitness. 2005;45(1):38-43. Bergmark A. Stability of the lumbar spine. A study in mechanical engineering. Acta Orthop Scand suppl. 1989;60(230): 1-54. Cholewicki J, Panjabi MM, Khachatryan A. Stabilizing function of trunk flexor-extensor muscles around a neutral spine posture. Spine. 1997;22(19):2207-12.

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