중간볼기근 근력강화 운동프로그램이 한 다리 스쿼트 시 하지정렬과 보행 시 근활성도에 미치는 영향

Abstract

The purpose of this study was to identify and compare the effect of 3 types of 6-week Gluteus Medius(GM) Strengthening Program (Clamshell exercise[CL], Side lying bridging[SB], and Side-lying hip abduction[HA]) on lower extremity alignment during single leg squat, GM strength, and GM activation during gait among healthy twenties. A total of 32 healthy adults(21 males and 11 females) participated in this study and they were randomly divided into three groups (CL=11, SB=11, and HA=10). Before and after applying each GM strengthening program, the lower extremity alignment during single leg squat, GM strength, and GM activation during gait were measured. 2D motion analysis was used to identify the angle of hip abduction and extension, Dynamic Q-angle, and the angle of knee flexion in ipsilateral leg during single leg squat. The hand-held dynamometer was used to measure manual strength of GM, and GM muscle activity in from heel strike to mid-stance (HM period) and from mid-stance to toe-off (MT period) during gait by using the electromyography(EMG).

The conclusions are as follows :

1. In the lower extremity alignment during single leg squat, HA group had increased hip extension angle of ipsilateral leg during single leg squat after applying 6-week program compared to before it. Also, when squatting with left leg, left hip abduction angle of HA group increased after applying program.

2. All 3 groups showed a significant increase in GM strength after applying 6-week program compared to before.

3. The difference in the ipsilateral gluteus medius muscle activity of the stepping leg during gait after the application of the exercise program showed that the CL group had decreased GM muscle activities in the HM and MT periods during the stance phase on right leg and the HM period on left leg. The SB group showed decreased GM muscle activities in both HM and MT periods during the stance phase regardless of legs, and the GM muscle activity of HA group decreased in MT period during the stance phase on left leg.

As a result of this study, the HA exercise was more positive effect on dynamic lower extremity alignment compared to CL and SB exercises, while the SB was most effective exercise for strengthening GM during gait. These results will provide useful information on the design of GM strengthening exercise programs for rehabilitation and injury prevention of lower extremity.