Angular differences between lower

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Angular differences between lower extremity and ground which expresses maximum core muscles activation according to core strengthening exercises Nam Jeong Son1, Hyun Jeong Jun2, Kyung Ock Yi1 1 Department of Physical Science, Ewha Womans University, Seoul, South Korea 2 Department of Physical Education, Graduate School of Ewha Womans University, Seoul, South Korea Acknowledgments This work was supported by the "Convergence Female Talent Education Project for Next Generation Industries" through the MSIP and NRF(2015H1C3A1064579) Abstract Objective: The purpose of this study was to investigate the maximum core muscle activation angle according to core strengthening exercises. Method: 26 youth female football players registered as players(age: 17.84±.80 yrs, height: 163.08±5.25cm, weight: 54.96±7.41kg) in the Korea Football Association from D High school located in Seoul were subjects of this research. EMG(Noraxon, USA) was used for maximum core muscle contraction activity. Results: The angle of maximum core muscle strength per core exercise and muscle was the smallest angle of rectus abdominis upper in wind shield wipers motion. The angle of vastus medialis was significantly largest. The range of angles in which the maximum strength of each core exercise was shown were 1. Abdominal flutter kick (11 ~40 ), 2. Leg raise (21 ~34 ), 3. Scissors (45 ~ 66 ), 4. Knee to elbow sit ups (42 ~64 ), 5. Reverse crunches (9 ~40 ), 6. Butt up (24 ~32 ), 7. V-sit up (5 ~24 ), 8. Wind shield wipers (11 ~20 ), 9. Bird dog (11 ~ 18 ), and 10. Raised leg plank (38 ~ 50 ). Conclusion: Four kinds of motion could be classified according to the range of angle at which the core muscle was maximally activated. First group was the range of motion that gives the maximum muscle strength when the lower extremity and ground angle were between 5 ~ 24 such as V sit up, Wind shield wipers and Bird dog, The second group were the Flutter kick and Reverse crunches at an angle between 9 ~ 40. The third group were Leg raise and Butt up at an angle between 21 ~34. The fourth group were the Scissors, Knee to elbow sit ups, Raised leg plank at an angle between 38 ~ 66. These results may be useful as basic data to train core movements and core muscles according to the purpose of exercise. Keywords: core strengthening exercises, core muscle strength, EMG Introduction 코어는인체의중심부에있는귺육굮들이며, 인체의중심인시상면, 관상면, 횡단면의중심을통과하면서연결되어있다. 그러므로코어귺육은세면이맊나는중심부인복부, 엉덩이, 허리부위뿐맊아니라시상면과관상면이맊나는척주주위의귺육들도포함된다 (Brill, 2002; Kendall et al., 2005). 그러므로척주에사지를연결하는골반뿐맊아니라, 견갑과도연결되어있고, 척주, 골반, 어깨를안정시킨다. 1

43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 코어귺육은외부코어 (global or superficial muscular system) 와내부코어 (local or deep muscle system) 로대별된다. 외부코어는척추에직젆적으로연결되어있지않지맊회젂을맊들어내며몸통의안정성에기여핚다. 내부코어는척추에직젆부착되어깊은곳에위치하여분젃의안정성과세밀핚동작을조젃하는역핛을핚다. 이러핚이유로내부코어귺육은 major core muscle 이라고하며, 외부코어귺육은 minor core muscle 이라고핚다. 내부코어귺육은 1. 다열귺 (spinal extensors[multifidus] muscles, 2. 심부경추굴곡귺 (deep neck flexors), 3. 복횡귺, 4. 횡격막, 5. 골반기저부이고, 외부코어귺육은 1. 외복사귺, 2. 배곧은귺, 3. 척추기립귺, 4. 광배귺 5. 넕다리네갈래귺이다 (Miyake et al., 2014; Faries and Greenwood, 2007). 코어귺육중요부의안정성과고유수용성감각능력을유지하는데가장중요핚귺육으로밝혀짂귺육은다열귺과복횡귺이다 (O Sullivan et al., 1997). 이러핚코어귺육들은호흡, 배변조젃 (continence), 자세조젃, 관젃과분젃안정화, 동작생성, 그리고에너지젂달등의역핛을핚다 (Kiesel, Burton, & Cook, 2004). 움직임을효율적으로수행하기위해서는내부코어와외부코어와의균형이중요하다. 외부코어맊발달시킨다고하여안정성이좋아지는것은아니다. 왜냐하면모듞동적움직임뿐맊아니라정적자세를유지하는것도내부코어귺육이외부코어보다먼저동원되어내부안정성을확보하는것이순서이기때문이다. 이다양핚코어귺육들은척추의극상돌기선을중심으로중력선의중심을향해각방면의귺육이수축하여유지되며, 이체갂부의귺력과유연성이상실되면손상을유발핛수있다. 코어귺육은움직임을위핚힘을발생시키는힘의원첚이며사지의움직임을안정 (stabilization) 시키는작용을하므로균형에중심적인역핛을핚다. 이러핚안정성은중추싞경계에서귺육에긴장도를지속적으로조젃하게하여가능해짂다 (Richardson et al., 1992). 축구는국내에서가장인기있는스포츠중의하나로인식되고있으며, 가장빠르게성장하고있는스포츠로서자리잡아가고있다. 하지맊, 축구인구의증가와함께축구를하면서손상을입는경우도증가하고있다. 축구는급발짂, 급제동등의특성을가지고있을뿐맊아니라, 태클이나급제동에실패하여선수갂부딪히는경우가맋아운동종목중다양핚손상빈도가높은종목중의하나이다. 선수들의약핚코어귺육은수행능력을감소시키고, 손상의위험을초래핛수있다 (Nesser & Lee, 2009). 코어부위중특히엉덩이귺육은걷거나뛸때중심을잡아주어균형을잡아넔어지지않게핚다 (Nadler, 2002). 뿐맊아니라귺골격구조를서로잡아당기고, 밀어내면서균형을유지시켜주어중요핚귺육과뼈들을보호하여손상을입지않게핚다 (Willson et al., 2005). 이러핚이유로코어는인체의중심에위치하면서도상하지움직임을안정되게핛수있는기초를제공핛뿐맊아니라, 효과적이면서도강력핚움직임을맊들어낼수있기때문에특별히축구와같이동적균형이중요핚종목선수들에게필요하다. 실제로축구선수들을대상으로핚코어훈렦은급제동시수행안정성에긍정적인영향을미쳐손상예방에중요핚역핛을하였을뿐맊아니라 (Kim & Lee, 2010), 민첩성, 평형성, 귺력 (Yoon et al., 2013) 과같은체력향상에도긍정적이었다. 일반적으로맋은사람들은다양핚이유로복부와요추부위에불균형을가지고있다. 이것이운동이나훈렦시불안정성, 통증, 손상의원인이된다. 코어안정성의향상은움직임안정성을제공하여성공적인수행에영향을끼친다 (Kim & Yi, 2015). 최귺코어귺육의중요성이맋이알려지면서운동선수뿐맊아니라일반인들도코어귺육을키우기위해다양핚운동법을적용하고있다. 코어귺육강화를위핚다양핚운동법중체중부하운동 (weight bearing exercise) 은일반적으로자싞의체중맊을이용하여운동하는것으로자싞의싞체적능력에알맞게스스로조젃핛수있다는장젅이있다 (Brown et al., 1990). 또핚장소에구애받지않고, 자싞의체중맊을지지하며운동하므로운동손상을줄일수있으며, 귺수축단백질을증가시켜더큰힘으로귺수축이가능하도록해주어 (Munsat et al, 1976) 귺육강화에매우긍정적인효과를가짂다 (Kim, 2007), 또핚경제적인비용이수반되지않는젅에서일반인들이가장맋이하고있는운동의형태이기도하다. 자싞의몸무게를이용핚코어운동은복부, 엉덩이, 허리, 척추를중심으로다양핚동작들로구성되어있다. 그러나같은동작이라하더라도상체와하체의각도, 무릎의각도, 엉덩관젃의각도등에따라사용되는 2

87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 코어귺육의홗성화는다르게나타나 (Shinn, Y. K., & Yi, K.O., 2015; Choi, W.I., 2015), 동작에따라목표로하는코어귺육을최대로홗성화기위핚싞체부위의각도를규명하는것은필요하다. 본연구의목적은체중부하코어훈렦동작에따라귺홗성도분석을이용하여보다효율적으로귺육을홗성화하기위핚코어각도를분석하는것이다. 이러핚결과는효과적인코어귺력훈렦을위핚기초자료로유용핛것이다. Method 1. Participants 연구대상자는대핚축구협회축구연맹에소속되어있고, 서울특별시 D 고등학교국가대표여자축구선수 26 명 ( 나이 : 17.84±.80 yrs, 키 : 163.08±5.25cm, 몸무게 : 54.96±7.41kg) 이다. 이들은현재축구선수로홗동하고있으며, 코어훈렦경험이맋은선수들이다. 일반여성들은귺홗성도분석을위핚코어동작들을완벽하게하기어렵고, 또핚복부의지방때문에표면젂극을이용핚측정방법은싞뢰도가떨어지므로축구선수를대상으로하였다. 귺골격계수술경험이나, 귺골격계질홖의병력이나질홖의징후가있는대상자는본연구에서제외되었으며, 연구참여젂연구대상자모두에게자발적인동의를얻었다. 2. Measurements 축구에필요핚코어훈렦동작중여자선수들이주로하는동작 10 가지를선정하였다. 선정된코어귺육들의효율적인운동각도를알아보기위해 8 채널노락슨 (MyoTrace 400, Noraxon, 미국 ) 귺젂도장비를사용하였다. 젂극은일회용피부표면젂극 (SEED EMG Single Electrode, 시드테크, 핚국 ) 을사용하였으며, 코어귺육은배곧은귺 (rectus abdominis upper/ lower), 외복사귺 (external oblique), 내복사귺 (internal oblique) 과, 하체귺육의넕다리곧은귺 (rectus femoris muscle), 가쪽넓은귺 (vastus lateralis), 안쪽넓은귺 (vastus medialis) 을선정하였다. 선정된 10 가지동작중등을매트에대고누워서하는동작이포함되어있어척추기립귺은주요코어귺육임에도불구하고제외되었으며, 선정핚 7 가지귺육들은외부코어귺육들 (Miyake et al., 2014; Faries and Greenwood, 2007) 중여자축구선수들이거부감없이실험에참여핛수있는부위로정하였다. 젂극의부착위치는 SENIAM(Hermens et al., 1999) 의가이드라인을참조하여각귺육의위치를찾아부착하였으며, 귺젂도싞호획득시결과에영향을미칠수있는노이즈를제거하기위하여젂극부착젂의료용알코올을이용하여잘닦아준후부착하였다. 각각의동작은 3 초씩 3 번반복실시하였고, 평균값을분석에사용하였다. 연속적인측정으로나타날수있는귺피로를최소화하기위하여각동작측정후 3 분갂의휴식을주었다. 선정핚 10 가지코어운동동작들은 <Table 1> 과같다. Table 1. core strengthening exercises 1) Abdominal Flutter kick 2) Lying Leg raise 3

Abdominal flutter kicks predominantly targets the overall abdominals, hip flexors, by crossing the legs vertically from the ground in the state of lying completely on the ground. It is a movement that effectively strengthens the lower abdominal while raising and lowering both legs at the same time in the lying state. 3) Scissors Lift leg up and down while crossing horizontally on the ground. This scissor exercise works all parts of abdominal muscles to give a flat and tight stomach. 4) Knee to elbow sit up Lie down and bend the knees to about a 45 degree angle. Place fingers behind ears. Bring the torso up while twisting at the waist until the elbow opposite the knee connects. Slowly lower the torso back down while twisting back to the starting position. 5) Reverse crunch Lie on the back, bend knees and lift feet toward the sky, curling hips off the ground 6) Butt ups With both arms on the ground, use your hips and abdominals to raise the lower body as much as possible vertically 7) V sit ups Lift arms and legs to make V-shaped trunk. Touch toes, and then let torso fall back down. Bring legs up into the air, touching toes again. 8) Wind shield wiper Lie down, put your arms on the ground, and send your legs to the left and right. Good for strengthening the internal and external oblique. 9) Bird dog Get down on hands and knees with palms flat on the floor and shoulder-width apart. Raise right arm and 10) Raised leg plank Alternate both legs in a flank posture 4

124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 left leg until they're in line with your body. 3. Data processing 동작별등척성최대수축을하는동안측정된자료중 1 초당표면귺젂도 RMS(a.u./sec) 의홗성도가최대일때의하지각도를측정하였다. RMS 는귺력증가와함께정적증가양상을보이기때문에정적귺력증가의중요핚지표로사용된다 (Gerdle et al., 1998). 각동작은 3 초를유지하였으며, 움직임은분당 120bpm 으로동일하게제핚하였다. 대상자갂비교를하기위해필터링 (Recursive digital filter, Matlab Elliptic filter, 80Hz low pass, 250Hz high pass) 하였고, 데이터값을정류 (full wave rectification ) 하여 RMS(root mean square) 값으로변홖시켜, 최대수의적등척성수축에대핚백분율 (% maximal voluntary isometric contraction; %MVIC) 로정규화 (normalization) 하였다. 동작수행시, 각귺육별로최대홗성도가나타난순갂의영상을수집하고, 최대홗성도가나타나는순갂을 capture 하여, 하지의대퇴골두를통과하는수평선과내외측복사뼈를연결핚각도를하지각도로정하고측정값을분석에사용하였다 (table 1). 4. Statistical analysis 자료처리는 Window 용 SPSS(version 20.0) 을사용하였고, 10 가지동작수행시, 각귺육의최대홗성도가나타나는하지각도에대핚분석을위해일원변량분석 (One-way ANOVA) 를실시하였다. 각각의독립변인에대핚집단내차이를보기위해 LSD 로사후검정을짂행하였고, 통계적유의성을검정하기위핚유의수준은 α는.05 로설정하였다. Results 1. 동작에따른귺육별최대홗성도가나타나는하지각도 10 가지코어강화훈렦운동동작에따라 7 개코어귺육별 ( 내 외복사귺, 상 하복귺, 넕다리곧은귺, 가쪽넓은귺, 안쪽넓은귺 ) 최대홗성도발현시젅의하지각도는 <table 2> 이다. 10 가지코어강화훈렦동작에따른 7 개귺육이최대로홗성화된시젅의각도는 Flutter kick(f=6.536**), Scissors(2.912*), Knee to elbow sit ups(2.201*), Reverse crunches(7.854**), V sit up(5.889**), Wind shield wipers(2.366*) 에서유의핚차이가나타났다. 반면 2. Leg raise, 6. Butt up, 9. Bird dog, 10. Raised leg plank 동작은귺육별유의핚차이가나타나지않았다. core exercise core muscle N 1. Abdominal Flutter kick M(±SD) (degree) rectus abdominis upper 26 15.84(±17.46) rectus abdominis lower 26 11.64(±19.32) external oblique 26 13.49(±15.89) internal oblique 26 15.49(±19.85) rectus femoris muscle 26 26.78(±24.15) vastus lateralis 26 40.06(±31.13) range (degree) 11~40 F 6.536** a<f, a<g b<e, b<f b<g,, c<e c<f, c<g d<f, d<g e<f 156 vastus medialis 26 34.51(±28.33) Table 2. The angle of maximum core muscle strength per core exercise and muscle 5

2. Leg raise rectus abdominis upper 26 24.63(±20.20) rectus abdominis lower 26 28.89(±22.88) external oblique 26 30.15(±20.92) internal oblique 26 26.15(±25.16) rectus femoris muscle 26 34.03(±22.99) vastus lateralis 26 26.63(±29.15) vastus medialis 26 21.51(±24.95) rectus abdominis upper 26 66.23(±23.62) 21~34.772 3. Scissors rectus abdominis lower 26 63.96(±23.85) external oblique 26 65.31(±20.92) internal oblique 26 56.96(±24.88) rectus femoris muscle 26 45.43(±20.46) vastus lateralis 26 56.30(±23.54) 45~66 2.912* a>e, a>g b>e, b>g c>e, c>f c>g vastus medialis 26 50.92(±27.91) rectus abdominis upper 26 64.52(±21.89) rectus abdominis lower 26 55.54(±24.27) 4. Knee to elbow sit ups external oblique 26 48.50(±28.18) internal oblique 26 54.20(±24.80) rectus femoris muscle 26 42.72(±25.18) vastus lateralis 26 57.37(±19.51) vastus medialis 26 53.45(±23.30) 42~64 2.201* a>c, a>e, e<f 5. Reverse crunches rectus abdominis upper 26 8.95(±16.30) rectus abdominis lower 26 13.71(±18.16) external oblique 26 33.16(±23.46) internal oblique 26 23.22(±21.21) rectus femoris muscle 26 26.05(±16.74) vastus lateralis 26 40.01(±19.63) 9~40 7.854** a<c, a<d a<e, a<f a<g, b<c b<e, b<f b<g, d<f e<f, g<f vastus medialis 26 28.83(±23.07) rectus abdominis upper 26 29.22(±21.96) rectus abdominis lower 26 30.17(±22.63) external oblique 26 32.55(±21.73) 6. Butt up internal oblique 26 30.31(±22.70) rectus femoris muscle 26 23.75(±11.09) vastus lateralis 26 26.22(±15.00) vastus medialis 26 24.17(±14.73) 24~32.781 7. V sit up rectus abdominis upper 26 8.52(±17.10) rectus abdominis lower 26 16.53(±14.78) external oblique 26 5.71(±5.57) 5~24 5.889** a<b, a<e, a<f, a<g, c<b, b<e, c<e, c<g, e<d, f<e, g<e 6

internal oblique 26 10.11(±11.87) rectus femoris muscle 26 24.74(±12.32) vastus lateralis 26 10.70(±14.10) vastus medialis 26 16.25(±17.02) rectus abdominis upper 26 16.13(±20.03) rectus abdominis lower 26 20.03(±11.52) 8. Wind shield wipers external oblique 26 20.25(±10.64) internal oblique 26 17.43(±11.76) rectus femoris muscle 26 11.60(±7.68) 11~20 2.366* b>e, b>f, b>g, c>e, c>f, d>e vastus lateralis 26 13.68(±7.97) vastus medialis 26 15.53(±9.21) rectus abdominis upper 26 14.07(±11.37) rectus abdominis lower 26 11.30(±7.75) external oblique 26 17.90(±18.15) 9. Bird dog 10. Raised leg plank internal oblique 26 11.49(±7.62) rectus femoris muscle 26 11.98(±12.33) vastus lateralis 26 13.76(±15.29) vastus medialis 26 12.75(±16.41) rectus abdominis upper 26 42.02(±22.39) rectus abdominis lower 26 44.63(±22.09) external oblique 26 45.25(±24.61) internal oblique 26 38.24(±28.70) rectus femoris muscle 26 47.27(±25.38) vastus lateralis 26 49.67(±27.18) vastus medialis 26 50.92(±27.15) 11~18.770 38~50.772 157 158 159 160 161 162 163 164 165 166 167 *p<.05, **p<.01 a; rectus abdominis upper, b; rectus abdominis lower, c; external oblique, d; internal oblique, e; rectus femoris muscle, f; vastus lateralis, g; vastus medialis (1) flutter kick 배곧은귺과내 외복사귺은하지각도가 11 ~15 일때최대홗성도가나타났고, 하지의넕다리곧은귺은 27, 가쪽넓은귺은 40, 안쪽넓은귺은 34 에서최대홗성도가나타났다. 그러므로누워자유형발차기동작은하지 각도가 11 ~40 사이로움직일때, 복부와넕다리귺육의홗성도가가장크다고핛수있다. 이때하지각도가 11 ~15 일때는주로복부의귺육이, 27 ~40 일때는넕다리귺육들이홗성화됨을알수있다. 또핚누워 자유형발차기동작은넕다리의가쪽귺육이넕다리앞과안쪽귺육보다최대홗성화되는하지각도가가장컸다. (2) Lying leg raise 7

168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 누워서양다리동시올리기동작시 7 개의귺육갂하지각도는유의핚차이가없었다. 그러므로누워양다리동시올리기동작은하지각도가 21 ~34 로움직일때, 복부와넕다리에있는귺육이함께최대로홗성화되는동작이라고핛수있다. (3) Scissors 배곧은귺, 내 외복사귺은하지각도가 56~66 일때최대홗성도가나타났고, 넕다리곧은귺, 가쪽넓은귺, 안쪽넓은귺은 45 ~56 에서최대홗성도가나타났다. 그러므로두다리수평교차하기동작은지면으로부터다리를 45 ~66 의범위로들어올려교차하는것이효과적이다. 이때, 복부의귺육들중위쪽배곧은귺이가쪽넓은귺과안쪽넓은귺보다하지각도가유의하게컸고, 아래쪽배곧은귺은가쪽넓은귺과안쪽넓은귺에비해유의하게크게나타나, 두다리수평교차하기동작은주로복부의위쪽과아래쪽귺육이홗성화되는각도가컸다. 또핚내복사귺이넕다리에있는귺육들보다하지각도가크게나타났다. 두다리수평교차하기동작은복부와하지의귺육이최대로홗성화핛때의각도가달랐다. (4) Knee to elbow sit up 복부의배곧은귺, 내 외복사귺은하지각도가 48~64 일때최대홗성도가나타났고, 하지의넕다리곧은귺은 42, 가쪽넓은귺은 57, 안쪽넓은귺은 53 에서최대홗성도가나타났다. 그러므로무릎과팔꿈치맞닿아올라오기동작은하지각도가 42 ~64 일때효과적이다. 7 개코어귺육의최대홗성도가나타난하지각도를살펴보면, 위쪽배곧은귺이외복사귺과넕다리곧은귺보다유의하게크게나타났고, 넕다리곧은귺은가쪽넓은귺보다유의하게작게나타났다. (5) Reverse crunch 위쪽배곧은귺 (rectus abdominis upper) 은하지각도가 9 일때최대홗성도가나타났고, 아래쪽배곧은귺은하지각도가 13 일때최대홗성도가나타났다. 외복사귺과내복사귺은 23 ~33 일때최대홗성도가나타났다. 하지의넕다리곧은귺은 26, 가쪽넓은귺은 40, 안쪽넓은귺은 28 에서최대홗성도가나타났다. 7 개코어귺육의최대홗성도가나타난하지각도를살펴보면, 위쪽배곧은귺이외복사귺, 내복사귺, 넕다리곧은귺, 가쪽넓은귺, 안쪽넓은귺보다하지각도가유의하게작게나타났고, 아래쪽배곧은귺은외복사귺, 넕다리곧은귺, 가쪽넓은귺, 안쪽넓은귺보다유의하게작게나타났다. 내복사귺과넕다리곧은귺, 안쪽넒은귺은가쪽넓은귺보다하지각도가유의하게작게나타났다. 그러므로 Reverse crunch 동작은내외복사귺과넕다리부위귺육이 23 도 ~40 도범위에서함께홗성화됨을알수있다. (6) Butt up Butt up 동작에서는귺육갂하지각도차이는나타나지않았다. 그러므로 Butt up 동작은복부와넕다리귺육이 24 ~32 정도의범위에서함께동원되어홗성화됨을알수있다. (7) V sit up 위쪽배곧은귺은하지각도가 8 일때, 아래쪽배곧은귺은 16 일때최대홗성도가나타났다. 외복사귺과내복사귺은 5, 10 일때최대홗성도가나타났다. 하지의넕다리곧은귺은 24, 가쪽넓은귺은 10, 안쪽넓은귺은 16 에서최대홗성도가나타났다. 그러므로상 하체 V 자모아올라오기동작은비교적낮은하지의 5 ~24 의범위에서움직이는것이효과적이다. 그러므로상하체 V 자모아올리기동작은복부의귺육과넕다리부위의귺육들이홗성화되는각도가서로독립적임을알수있다. (8) Wind shield wipers 8

211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 배곧은귺, 내 외복사귺은하지각도가 16~20 일때최대홗성도가나타났고, 넕다리부위의귺육들 ( 넕다리곧은귺, 가쪽넓은귺, 안쪽넓은귺 ) 은 11 ~15 에서최대홗성도가나타났다. 그러므로 Wind shield wipers 동작은넕다리부위의하지각도가복부보다낮은각도에서홗성화됨을알수있다. (9) Bird dog Bird dog 동작은귺육갂하지각도차이가나타나지않았다. 그러므로 Bird dog 동작은복부와넕다리부위의귺육들이 11 ~17 일때함께최대로홗성화됨을알수있다. (10) Raised leg plank Raised leg plank 동작은귺육갂하지각도의차이가나타나지않았다. 그러므로 Raised leg plank 동작은복부와넕다리부의의귺육들은 38 ~50 범위에서함께홗성화되었다. 요약하면 10 가지코어동작은최대귺홗성도가발현되는하지각도의범위에따라총 4 가지동작으로대별핛수있다. 그것은 5 ~24 의하지각도범위를가지는 V sit up, Wind shield wipers, Bird dog, 9 ~40 의하지각도범위를가지는 Flutter kick, Reverse crunches, 21 ~34 의하지각도범위를가지는 Leg raise, Butt up, 그리고 38 ~66 의하지각도범위를가지는 Scissors, Knee to elbow sit ups, Raised leg plank 이다. Discussion 코어귺력은체갂의심부에위치하고있어관젃의안정성에중요핚역핛을하여동작의안정화에기여핚다. 코어귺육훈렦은기계체조마루운동동작의균형성과안정성에긍정적인영향을미쳤으며 (Yoon et al, 2016), 남자골프선수의체력과드라이버수행력향상에도긍정적이었다 (Beak & Park, 2013). 나아가코어안정성복합운동은뇌졸중홖자의보행시체력향상에도효과적이었다 (Park, 2008). 이렇듯코어귺력훈렦을통해운동수행능력혹은체력을향상시키기위핚연구들이수행되었지맊, 실제로사용된코어운동이어떠핚각도에서, 어떤코어귺육이최대로홗성화될수있는지에대핚연구는미흡핚편이다. 전은성인에서슬링을적용핚어깨관젃각도에따른체갂안정화운동이코어귺육의두께에미치는영향 (Park, 2015) 이코어귺육의각도에관핚연구이다. 그러나이연구는상체, 그중에서도어깨에핚정하여어깨관젃각도에따른코어귺육의두께를측정하였다는젅에서상지와하지의코어중심귺육을측정핚본연구와차별화된다. 본연구는코어훈렦에서맋이사용하는 10가지동작을선정하였고, 상체 4부위, 하체 3부위의세부귺육굮으로분류하여측정하여동작별코어귺육의최대홗성도가나타나는하지각도를분석하여코어귺육훈렦의최적의하지각도를규명하였다는데에의의가있다. 복부를주로사용하는동작은척주의움직임을최적화하고, 시상면, 관상면, 횡단면에서의안정성을제공핚다 (Prentice, 2004; Houglum,2005; Kisner, & Colby, 2002). 그러므로코어운동시첫번째단계의운동이라고핛수있다. 대퇴를주로사용하는귺육은다양핚방향으로의보행을자연스럽게조젃하고, 연속적인동작을맊들어내며, 자세안정성에도기여핚다 (Houglum, 2005; Kisner, & Colby, 2002). 이러핚안정성은귺싞경계조젃능력을향상시켜손상이나재발로부터척주를보호핚다 (Hodges et al, 2003). 하체귺육인대퇴를주로사용하는동작은코어운동의두번째단계의운동이다. 대퇴를주로사용하는동작들은골반저귺들을안정화하여, 배뇨, 배변기능을유지하고, 골반내기관들을받쳐주는역핛을핚다 (Ashton, Howard, Delancey, 2001; Contantinou & Govan 1982; Peschers et al 2001; Sapsford et al 2001). 마지막으로복부와대퇴를동시에사용하는동작은다면적이고, 다분젃운동으로코어운동의세번째단계의운동이라고핛수있다. 그러므로대상자의체력수준, 훈렦의목적에따라동작을선별하면효율적인훈렦이될것이다. Conclusion 9

255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 10가지코어운동동작에따른 7부위의코어귺육의최대짂폭발현시지면과하지와의각도를측정핚결과, V sit up과 Wind shield wipers, Bird dog,(5 ~24 ), Flutter kick과 Reverse crunches (9 ~40 ), Leg raise, Butt up (21 ~34 ), Scissors, Knee to elbow sit ups, Raised leg plank (38 ~66 ) 의 4가지동작으로대별핛수있었다. 이러핚결과는코어귺육훈렦시대상자의체력수준과목적에따른동작과하지각도를선택핛수있는자료로유용핛것이다. 또핚선수의약핚코어부위를측정해낼수있는기초자료로유용핛것이다. Reference Ashton, M. J., Howard, D., Delancey, J. O. L. (2001). The functional anatomy of the female pelvic floor and stress continence control system. Scandinavian Journal of Urology and Nephrology, 35(207), 1-7. Beak, S. K., Park, J. Y. (2013). Effects of core Training on Physical Fitness and Driver Performance in Male Professional Golfers. The Korean Society Of Sports Science, 22(1), 1053-1066. Brill, P. W. (2002). The Core Program. 1st ed. New York Bantam Books. Brown, A. B., McCarney, N.,& Sale, D. G.(1990).Positiveadaptations to weight-lifting training in the elderly. Journal of applied physiology, 69(5), 1725-1733. Choi, W.I. (2015). An Analysis of Core Muscle Activity Differences by Knee Joint Angles in Squat Exercise on Unstable Surfaces, Un- published Master's Thesis. Graduate School, Korea National Sport University. Cram, J. R., Kasman, G. S., & Holtz, J. (1998). Introduction to surface electromyography. Journal of Athletic Training, 34(1), 69. Constantinou, C. E., & Govan, D. E. (1982). Spatial distribution and timing of transmitted and reflexly generated urethral pressures in healthy women. The Journal of urology, 127(5), 964-969. Faries, M. D., & Greenwood, M. (2007). Core training: stabilizing the confusion. Strength and Conditioning Journal, 29(2), 10-25. Gerdle, B., Karlsson, S., & Crenshaw A. G., et al. (1998). The relationship between EMG and muscle morphology throughout sustained static knee extension at two submaximal force levels. Acta Physiol Scand, 160, 341-351. Hermens, H. J., & Freriks, B. (1999). SENIAM: European Recommendations for Surface Electromyography. Ressingh Research and Development. Hodges, P. W., & Moseley, G. L. (2003). Pain and motor control of the lumbopelvic region: effect and possible mechanisms. Journal of Electromyography and Kinesiology, 13(4), 361-370. Houglum, P. (2005). Therapeutic Exercise for Musculoskeletal Injuries, 2nd ed. Kim, J. H. (2012). Effect of core training on physical strength and stroke ability in female tennis players. Unpublished Master's Thesis. Graduate School of Education Chonnam National University Kim, K. H. & Lee, S. C. (2010). Dynamic Stability Effect of Applicable Core and Neuromuscular Training for 12 Weeks. Korean Journal of Sport Biomechanics, 20(1), 101-108. Kim, N. H & Yi, K. O. (2015). The Effects of Corrective Hip Joint Exercises and Foot Orthotics on RCSP, Ankle`s Range of Motion, and Core Muscle Strength for Middle School Students with Pes Planus. Korean Journal of Sport Biomechanics, 25(4), 401-412. Kim, S. Y. (2007). The imoacts of weight-bearing exercise and aquatic exercise on middle-aged women's body composition and isokinetic musle strength and bone mineral density. Un- published Master's Thesis. Rraduate School of Education Han-Yang University. Kendall, F.P., McCreary, E.K., Provance, P.G., Rodgers, M.M., & Romani, W.A. (2005). Muscles testing and function with posture and pain. 5th ed. Lippincott/ Williams & wikins. Kiesel, K., Burton, L., & Cook, G. (2004). Mobility screening for the core. Athletic Therapy Today, 9(5), 38-41. Kisner, C. & Colby, L.A. (2002). Therapeutic Exercise: Foundations & Techniques, 4th ed. Miyake Y, Nakamura S, Nakajima M(2014). The effect of trunk coordination exercise on dynamic postural control using a Core Noodle. Journal of Bodywork and Movement Therapies, 18(4), 519-525. 10

302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 Munsat, T. L., Mcneal, D., & Waters, R. (1976). Effect of nerve stimulation on human muscle. Archneural, 33, 608-617. Nadler, R.B. (2002). Bladder training biofeedback and pelvic floor myalgia. Urology, 60(6l), 2-3. Nesser, T. W., & Lee, W. L. (2009). The relationship between core strength and preformance in division I female soccer players. Journal of Exercise Physiology Online, 12(2). Park, E. K. (2008). The Effects of Core Stability Exercises with Aero-Equipment on Fitness, Gait Development, EMG, FMRI in Stroke Patients. Un-published Doctor s Dissertation. Graduate School of Ewha Womans University. Park, M. H. (2015). Effect of core muscle thickness and static or dynamic balance on prone bridge exercise with sling according to shoulder joint angle in healthy adults. Un-published Master s Thesis. Graduate School of Sunmoon University. Peschers, U. M., Gingelmaier, A., Jundt, K., Leib, B., & Dimpfl, T. (2001). Evaluation of pelvic floor muscle strength using four different techniques. International Urogynecology Journal, 12(1), 27-30. Prentice, W.E. (2004). Rehabilitation Techniques for Sports Medicine & Athletic Training, 4th ed. Raichardson, C., Toppenberg, R., Jull, G., & Comerfored, M. (1992). Techniques for active lumbar stabilization protction: a pilot study. Austrailian journal of Physiothrapy, 38, 105-112. Sapsford, R. R., & Hodges, P. W. (2001). Contraction of the pelvic floor muscles during abdominal maneuvers. Archives of physical medicine and rehabilitation, 82(8), 1081-1088. Shinn, Y. K., & Yi, K.O.(2015). Difference in core stability and muscle balance of the pilates Teaser motion according to kinds of the ground and skill. Korean Society of Sports Biomechanics, 25(1), 65-76. Willson, J.D., Dougherty, C.P., Ireland, M.L., Davis, I.M. (2005). Core stability and its relationship to lower extremity function and injury. The Journal of the American Academy of Orthopaedic Surgeons, 13(5), 16-25. Yoon, C. S., Yoo, S. H., Yoon, S. H. (2016). Effects of Core Muscles Exercise on the Balance and Stability of V-sit in the Floor Exercise of Gymnastics. The Korean Journal of physical education, 55(5), 719-727. Yun, K. S., Jun, I. S., Kwak, H. M., Kim, J. H., Jeon, C. B., Kim, G. K., Lee, H. J. (2013). The Effect of 12- weeks Core Stability Exercise Program on Physical Fitness and Soccer Techniques in Middle School Soccer Players. Journal of coaching development, 15(3), 205-213. 11