J Korean Soc Phys Med, 2016; 11(2): 71-76 http://dx.doi.org/10.13066/kspm.2016.11.2.71 Online ISSN: 2287-7215 Print ISSN: 1975-311X Research Article Open Access 탄력밴드와아령에의한저항이다양한어깨관절외전각도에서중간어깨세모근의등척성수축에미치는영향 박민철 이상열 1 부산가톨릭대학교보건과학대학물리치료학과, 1 경성대학교이과대학물리치료학과 Deltoid Middle Fiber of the Isometric Contraction According to Elastic Band and Dumbbell on Various Shoulder Abduction Angle Min-Chull Park, PT, PhD Sang-Yeol Lee, PT, PhD 1 Dept. of Physical Therapy, College of Health Sciences, Catholic University of Pusan 1 Dept. of Physical Therapy, College of Science, Kyungsung University Received: April 12, 2016 / Revised: April 14, 2016 / Accepted: April 18, 2016 c 2016 J Korean Soc Phys Med Abstract 1) PURPOSE: The purpose of this study was to compare isometric contraction of deltoid middle fiber between elastic band and light dumbbell on various shoulder abduction angle. And this study intends to examine the compare with isometric contraction on deltoid middle fiber in various abduction angle of shoulder joint. METHODS: The participants of this study were Korean healthy adult in their 20s (n=60). The 8 channel surface electromyography was used to measure activity of the deltoid middle fiber at isomeric contraction on various abduction angle: 0, 30, 60, 90, 120 of shoulder joint using elastic band: red color Theraband and dumbbell: 2kg. The data used in the analysis of the present study was the root mean square. RESULTS: The deltoid middle fiber activation was not significantly different between elastic band and dumbbell at each abduction angle. The deltoid middle fiber activation significantly increased as more to increased shoulder abduction angle in elastic band and dumbbell. CONCLUSION: The elastic band and dumbbell was to provide the similarly load to the deltoid middle fiber isometric contraction on all of the shoulder abduction angle. The deltoid middle fiber activation increased as more to increased shoulder abduction angle in elastic band and dumbbell. These results may be an important reference in development of exercise on shoulder joint. Key Words: Dumbbell, Deltoid middle fiber, Elastic band, Shoulder abduction Corresponding Author : sjslh486@hanmail.net 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. 서론 어깨관절은구조적불안정성을다양한근육의작용을통하여보완하는대표적인관절이다 (Kronberg
72 J Korean Soc Phys Med Vol. 11, No. 2 등, 1990; Hess, 2000). 이와같은어깨관절의구조적인특징때문에근육의약화와잘못된협응은어깨관절에다양한질병을발생시킨다. 이러한구조적인형태로인하여근육의약화와불안정을동반하게되면다양한질병이발생시킨다. 선행연구들은불안정성이높은어깨관절의수술전과후그리고손상전과후의빠른기능회복을위해어깨관절안정성운동이필요하다고제시하였다 (John과 Brems, 2007). 어깨관절은구조적으로불안정하여근육의강화를통하여안정성을높일수있다. 어깨관절안정화를위한근력강화운동은어깨관절주변의근육들이조화로운움직임을증가시키기위한닫힌사슬운동 (Lee 등, 2011) 과단일근육의강화를위한다양한자세와각도에서의열린사슬운동을대표적인어깨관절강화를위한운동이라고할수있다 (Antony와 Keir, 2010). 또한주변관절을이용한어깨관절의안정성을높임으로써해당관절의근활성을높일수있는방법등을제시하고있다 (Lee 등, 2011; Lee, 2013). 어깨관절의근력강화를위해다양한저항도구를사용하고있다. 대표적인예로탄력밴드와아령이다. 탄력밴드는관절의움직임에따라다양한각도의저항을제공하며각도의변화에따라고정부위에서움직임부위가멀어지면서저항력이점차증가한다 (Brill 등, 1998). 아령은저항이항상중력방향으로고정되어있고저항의양이고정되어있다. 즉, 탄력밴드는점진적저항을밴드의탄력으로제공하는특징을가지고, 아령은모멘트팔에의존하여저항의양이변화되는특징을가진다. 이와같이두가지도구는저항양의결정에있어다른특징을가지고있지만구분없이많은운동에서활용되고있다 (Treiber 등, 1998). 중간어깨세모근은편마비환자의이완성마비시아탈구를예방하고, 어깨의움직임을원활히하며안정성을증가시키기위해중요한근육이다. 따라서본연구는다른특징을가진아령과탄력밴드를이용한저항의제공이어깨관절외전시각도에따라중간어깨세모근의활성에미치는영향을밝혀임상에서환자에게저항제공의방법결정에기초자료를제공하고자한다. Ⅱ. 연구방법 1. 연구대상본연구는우측이우세측인신체건강한성인 60명 ( 남 : 35명, 여 : 25명 ) 을대상으로실시하였다. 대상자의평균연령은 21.10±1.83세이며, 평균체중은 69.85±12.42 kg, 평균신장은 173.45±4.17cm이었다. 모든대상자는연구에대한상세한설명을듣고자발적으로연구참여에동의하였다. 2. 측정방법및연구절차본연구는어깨외전각도에따른중간어깨세모근의근활성도를측정하기위하여대상자를벽면으로부터 10cm 떨어진지점에발끝을위치키시고벽을마주보고서게하였다. 선자세에서대상자의어깨관절의위치를확인하고시작자세 ( 외전 0도 ) 로부터 30도, 60 도, 90도, 120도외전각도를측정하여벽면에표시하였다. 이후에대상자에게 2kg의아령과붉은색탄력밴드 (Theraband, The Hygenic Corp., U.S.A) 를무작위로제공하여각각 3번씩의외전동작을수행하도록하였다. 아령을이용한외전동작은시작자세 ( 외전 0도 ) 에서편안하게아령을손에쥐도록하였으며탄력밴드를이용한어깨외전동작은대상자가 0도외전자세에서탄력밴드를손에쥐었을때지면과의거리를측정하여탄력밴드의장력이발생하지않는길이를제공하였다. 어깨외전동작은자동설정된신호음에따라 0도, 30도, 60도, 90도, 120도에서각각 5초간유지하게하였으며표면근전도를이용하여각각의각도에서근활성도를측정하였다 (Fig. 1). 모든대상자는우세측에아령과탄력밴드를제공하여동작을수행하였다. 근활성도측정은표면근전도시스템 (LXM3204, LAXTHA INC., Korea) 을사용하였으며, Telescan 프로그램을이용하여분석하였다. 표면전극을적용하기전에피부저항을줄이고전극이피부에잘고정되도록하기위하여필요에따라면도를실시하고, 알콜솜으로닦아청결함을유지하도록하였다 (Hermens 등, 2000). 표면전극은 SENIAM(Surface Electromyography for the Non-Invasive Assessment of Muscles) 을기준으로
탄력밴드와아령에의한저항이다양한어깨관절외전각도에서중간어깨세모근의등척성수축에미치는영향 73 (a) 0 band (b) 30 band (c) 60 band (d) 90 band (e) 120 band (f) 0 dumbbell (g) 30 dumbbell (h) 60 dumbbell (i) 90 dumbbell (j) 120 dumbbell Fig. 1. The measuring position 중간어깨세모근에부착하였다 (SENIAM, 2011). 접지전극 (ground electrode) 는주두돌기 (olecranon process) 에부착하였으며, 모든표면전극은 Ag/AgCl 전극 (3M Inc., Korea) 을사용하였다. 근전도신호의표본추출률은 1,024Hz로설정하였으며대역통과필터 20~500Hz 와 60Hz 노치필터를이용하여필터링하였다. 수집된신호는 RMS (Root Mean Square) 값으로정량화하였다. RMS 값은측정된 5초중처음과마지막 1초를제외한 3초간의값을사용하였으며 3회측정한값의평균을이용하였다. 3. 통계처리본연구에서얻어진데이터는 SPSS win 12.0을사용하여통계처리하였다. 각각의어깨관절외전각도에서사용된저항제공방법 ( 아령, 탄력밴드 ) 에따른중간어깨세모근의활성도를비교하기위하여대응표본 t검 정을실시하였다. 그리고다섯가지의각도에따른중간어깨세모근의활성도를비교하기위해일원배치분산분석 (one-way ANOVA) 를사용하였다. 각각의각도사이에활성도차이를알아보기위하여사후검정은 LSD를사용하였다. 통계적유의수준 α는 0.05로하였다. Ⅲ. 결과각각의어깨외전각도에서탄력밴드와아령의부하가미치는영향을알아본결과, 모든각도에서아령과탄력밴드사이에유의한차이가없었다 (p 0.05). 탄력밴드의사용시각각의각도간근육활성도는유의한차이를보였다 (F=127.22, p 0.00)(Fig. 2). 사후분석결과탄력밴드사용시, 어깨외전 0도, 30도, 60도, 90도, 120도모든각도사이에유의한차이를보였다. 아령의
74 J Korean Soc Phys Med Vol. 11, No. 2 Table 1. Compression of deltoid middle fiber activation according to elastic band and dumbbell on various shoulder abduction angle angle elastic band dumbbell t p 0 23.12 ± 2.59 23.14 ± 2.20-0.2 0.91 30 92.60 ± 37.38 93.39 ± 32.71-0.47 0.64 60 167.46 ± 66.20 162.89 ± 58.74 1.21 0.23 90 275.73 ± 117.69 271.98 ± 92.03 0.66 0.51 120 351.06 ± 148.67 343.69 ± 131.83 0.86 0.39 mean±sd Fig. 2. Compression of deltoid middle fiber activation according to various shoulder abduction angle using elastic band and dumbbell 사용시각각의각도간근육활성도는유의한차이를보였다 (F=167.00, p 0.00)(Fig. 2). 사후분석결과아령의사용시, 어깨외전각도 0도, 30도, 60도, 90도, 120도모든각도사이에유의한차이를보였다. Ⅳ. 고찰본연구는탄력밴드와아령에의해제공된저항이 5가지어깨외전각도에서중간어깨세모근의등척성수축시활성도에미치는영향을알아보기위해실시하였다. 어깨관절의각도가증가할수록두가지도구모두에 적용되는모멘트팔은 90 까지늘어나며그이후의각도에서는줄어든경향을보이게된다 (Neumann, 2002). 예를들어어깨관절의굴곡과외전의경우이론적으로 90 외전또는굴곡에서모멘트팔이가장긴형태이므로외적인모멘트가최고치에이르는각도이다 (MacDonell 과 Keir, 2005). 모멘트팔의변화와함께아령은항상 2kg의무게로고정되어있지만탄력밴드는점진적으로증가되는저항을유발한다. 탄력밴드의점진적인저항의증가는대상자마다다르며객관적으로계산이불가능하다. 탄력밴드의경우어깨관절각도의변화에따라제공되는정확한저항치를계산할수없고아령과저항량을절대적인수치로비교할수는없으며저항의방향또한아령과동일하지않다. 하지만임상적으로혼용하
탄력밴드와아령에의한저항이다양한어깨관절외전각도에서중간어깨세모근의등척성수축에미치는영향 75 여사용하고있는저항도구를비교함으로써각각의특징을가진저항도구가중간어깨세모근에미치는영향을비교함으로써임상에서운동적용시기초자료를제공하고자실시되었다. 연구결과, 탄력밴드와아령을사용한저항의제공에따른중간어깨세모근의등척성수축시활성도에서는모든각도에서차이가나타나지않았다. 해당근육에가해진부하의양은많은조건들에의해서결정된다. 예를들어, 손잡기상태 (DiDomizio, 2006), 근육의수축종류 ; 등척성, 등속성, 구심성, 원심성수축등, 수축속도 (Antony와 Keir, 2010) 등에의해결정된다. 하지만본연구에서는다양한조건을감안하지않고각각의각도에서탄력밴드와아령의특징만을비교하기위해실시된연구로두가지특징의부하가선자세에서는동일한양의부하를중간어깨세모근에가한것으로생각된다. 본연구는동적인근육의활동이아닌등척성수축시나타난값을통계에사용하였기때문에차후연구에서동적인근육의활동에서의비교또한필요할것으로생각된다. 또한주변근육의활성으로인한보상이있었는지또는직접적인저항의양과방향이어떻게변하고있는지에대한연구가필요할것으로생각된다. 어깨외전각도가증가함에따라아령과탄력밴드의사용모두근육의활성이증가하는것은 90 외전이발생하는동안은근육의길이와모멘트팔의증가가모두작용하여활성도가증가한것으로생각된다. 그러나본연구에서지속적으로근활성도가증가한것은 90 이상에서모멘트팔이비록감소하게되지만어깨세모근의길이또한감소하게됨에따라팔의위치를유지하기위한기전에의해발생한결과라여겨진다. 근육의길이가줄어들면발생시킬수있는힘이감소하며이로인하여더욱많은운동단위가활성되어야저항에대한관절의위치를유지할수있기때문이다 (Antony와 Keir, 2010). 또한외전각도가증가함에따라상완골두의위치가변화하여안정성을보완하기위해주변근육의활성이높아져야하기때문이다 (Hughes 와 An, 1996; Jarvholm 등, 1991; Kronberg 등, 1990). 단, 탄력밴드의경우외전각도의증가로인한저항력 의점진적증가또한근육의활성을높인요소가될수있을것으로생각된다. 하지만본연구의결과와다른결과를제시한선행연구들도있었다. 반대되는연구결과를제시한연구들은등척성수축이아닌구심성 원심성수축을유발하여수축속도와힘의발생에대한개념이더해졌기때문에나타난결과로해석하고있다 (Komi 등, 2000). 향후연구에서모멘트팔의변화와근육의길이변화에대한상세한연구가이루어져야할것으로생각된다. Ⅴ. 결론어깨관절외전각도에따른아령과탄력밴드의저항이중간어깨세모근의등척성근활성에미치는영향에대한연구결과, 아령과탄력밴드는모든각도에서동일한중간어깨세모근의등척성근활성을보였으며, 어깨외전각도가증가할수록활성도가유의하게증가하는것으로나타났다. 이러한결과는탄력밴드와아령을사용한어깨관절의운동에중요한정보를제공할것으로생각된다. 하지만임상의적용에있어서는저항의방향이중간어깨세모근외에주변근육의활성에미치는영향에대한연구가이루어진후신중하게적용되어야할것으로생각된다. Acknowledgements 이논문은 2014년도부산가톨릭대학교교내연구비에의하여연구되었음. References Antony NT, Keir PJ. Effects of posture, movement and hand load on shoulder muscle activity. J Electromyogr Kinesiol. 2010;20:191-8. Brill PA, Probst JC, Greenhouse DL, et al. Clinical feasibility
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