• 한국전문물리치료학회지
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• 제11권4호
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• pp.19-29
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• 2004

Many muscles of the trunk and hip are capable of contributing to the stabilization and protection of the lumbar spine. To have optimal effectiveness, a training program should include dynamic back/stomach/hip exercises. This study was designed to assess the L5 level paraspinal, external abdominal oblique, and gluteus maximus muscle activities during various low back stabilization exercises. Participants were 26 healthy adults (13 males, 13 Females), aged 21 to 28 years. The surface electromyography (EMG) was recorded from the L5 level paraspinal, external abdominal oblique, and gluteus maximus muscles. The recorded signal was averaged and normalized to the maximal electromyographic amplitude obtained during the maximal voluntary contraction. The measurements were taken during 3 low back stabilization exercises. One-way analysis of variance with repeated measures was used to examine the difference, and a post hoc test was performed with least significant difference. A level of significance was set at p<.05. The significance of difference between men and women, and between the electromyographic recording sites was evaluated by an independent t-test. The EMG activity for the externus oblique and gluteus maximus muscles had significant differences among 3 exercises (p<.05). In males, the EMG activity for the external abdominal oblique muscle had significantly increased differences during exercises 1 and exercise 2 (p<.05). The gluteus maximus muscle had significantly increased differences during exercise 2 and exercise 3 (p<.05). In females, the multifidus muscle had significantly increased difference during exercise 3 (p<.05), the external abdominal oblique muscle had significantly increased difference during exercise 1 (p<.05). and the gluteus maximus muscle had significantly decreased difference during exercise 3 (p<.05). The results were that the external abdominal oblique muscle was apparently activated during the curl-up exercise in females and males, and the multifidus muscle was apparently activated during the bridging exercise in females and during the sling exercise in males and females.1)In comparison of the %MVC between males and females, exercise 2 and exercise 3 apparently activated of the multifidus and gluteus maximus muscles in both males and females (p<.05). The EMG activity of the gluteus maximus muscle of the males significantly increased during exercise 2 and exercise 3 (p<.05). The EMG activity the multifidus muscle of the females was significantly increased during exercise 2 and exercise 3 (p<.05). More research is needed to understand the nature of motor control problems in the deep muscles in patients with low back pain.

• 대한물리의학회지
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• 제17권2호
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• pp.21-28
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• 2022

PURPOSE: This study examined the effect of changes in the knee angle and weight shifting of the sole on the activity of the lower extremity muscles during bridge exercise. METHODS: The subjects of this study included 20 healthy adult women (mean age 29.8 ± 4.32). The subjects performed the bridge exercise under three weight-shifting conditions general bridge (GB), hindfoot press bridge (HPB), and fore-foot bridge (FPB) and at two knee angles (90° and 60°). During the bridge exercise, the activity of the quadriceps femoris (rectus femoris, vastus medialis oblique, and vastus lateralis) and biceps femoris muscles were measured using an electromyography sensor. RESULTS: In the quadriceps femoris, the muscle activity of HPB and FPB was significantly higher than that of the GB at knee angles of 90° and 60° (p < .05). In the biceps femoris, the muscle activity increased significantly in the order of GB < HPB < FPB, and the knee angle increased significantly at 60° rather than at 90° (p < .05). There was no significant difference according to the knee angle in all muscles except for the biceps femoris. CONCLUSION: These findings suggest that the weight-shifting bridge of sole bridge exercise was more effective in increasing the activation of the lower extremity muscles than the GB.

• 한국운동역학회지
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• 제19권4호
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• pp.655-661
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• 2009

본 연구는 기합소리를 세 가지 유형에 따라 인체내부의 근력의 차이를 비교하기 위해 H-reflex방법과 대퇴직근의 MVIC측정을 하여 추후 충격력과 운동수행에 미치는 효과를 규명하고 최적의 기합소리의 방법을 찾는데 도움을 주고자 설계하였다. 가자미근 H반사는 정강신경이 지나가는 오금에 전기자극을 주어 유발하였고, 표면근전도를 통하여 자료를 수집한 결과 기합 없이 측정한 결과 보다 기합을 지르면서 측정 시 28%증가하였고, 기합을 짧게 지른 직후 측정한 결과 29%가 증가한 것을 볼 수 있었다. 근전도 측정은 오른쪽 하지의 대퇴직근(Rectus femoris)에 표면전극을 부착해 MVIC를 측정한 결과 기합의 유형에 따라 10%와 1%의 증가를 보였다. 이러한 연구 결과에 비추어 기합이 운동신경효율성(H-reflex)과 MVIC의 크기를 변화시키는 것으로 보았을 때 근력증대에 긍정적인 요인을 미치는 것으로 사료되지만 근력증대의 변인 중 기합소리뿐만 아니라 호흡과 관련된 연구, 뇌파와 관련된 연구 등 일반화시킬 수 있는 많은 변인들에 관한 포괄적인 연구가 이루어 져야 할 것으로 사료된다.

• 한국운동역학회지
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• 제32권1호
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• pp.17-23
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• 2022

Objective: The aim of this study was to investigate the effect Tiger-step walking on the movement of the lower extremities during walking. Method: Twenty healthy male adults who had no experience of musculoskeletal injuries on lower extremities in the last six months (age: 26.85 ± 3.28 yrs, height: 174.6 ± 3.72 cm, weight: 73.65 ± 7.48 kg) participated in this study. In this study, 7-segments whole-body model (pelvis, both side of thigh, shank and foot) was used and 29 reflective markers and cluster were attached to the body to identify the segments during the gait. A 3-dimensional motion analysis with 8 infrared cameras and 7 channeled EMG was performed to find the effect of tigerstep on uphill walking. To verify the tigerstep effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at α=.05. Results: Firstly, Both Tiger-steps showed a significant increase in stance time and stride length compared with normal walking (p<.05), while both Tiger-steps shown significantly reduced cadence compared to normal walking (p<.05). Secondly, both Tiger-steps revealed significantly increased in hip and ankle joint range of motion compared with normal walking at all planes (p<.05). On the other hand, both Tiger-steps showed significantly increased knee joint range of motion compared with normal walking at the frontal and transverse planes (p<.05). Lastly, Gluteus maximus, biceps femoris, medial gastrocnemius, tibialis anterior of both tiger-step revealed significantly increased muscle activation compared with normal walking in gait cycle and stance phase (p<.05). On the other hand, in swing phase, the muscle activity of the vastus medialis, biceps femoris, tibialis anterior of both tiger-step significantly increased compared with those of normal walking (p <.05). Conclusion: As a result of this study, Tiger step revealed increased in 3d range of motion of lower extremity joints as well as the muscle activities associated with range of motion. These findings were evaluated as an increase in stride length, which is essential for efficient walking. Therefore, the finding of this study prove the effectiveness of the tiger step when walking uphill, and it is thought that it will help develop a more efficient tiger step in the future, which has not been scientifically proven.