• PNF and Movement
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• 제20권1호
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• pp.135-145
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• 2022

Purpose: The purpose of this study was to investigate the association between cognitive and motor inhibition by comparing muscle activity and ground reaction force during unplanned gait termination according to reaction time measured through the stop-signal task. Methods: Sixteen young adults performed a stop-signal task and an unplanned gait termination separately. The subjects were divided into fast and slow groups based on their stop-signal reaction time (SSRT), as measured by the stop-signal task. Electromyography (EMG) and ground reaction force (GRF) were compared between the groups during unplanned gait termination. The data for gait termination were divided into three phases (Phase 1 to 3). The Mann-Whitney U test was used to compare spatiotemporal gait parameters and EMG and GRF data between groups. Results: The slow group had significantly higher activity of the tibialis anterior in Phase 2 and Phase 3 than the fast group (p <0.05). In Phase 1, the fast group had significantly shorter time to peak amplitude (TPA) of the soleus than the slow group (p <0.05). In Phase 2, the TPA of the tibialis anterior was significantly lower in the fast group than the slow group (p <0.05). In Phase 3, there was no significant difference in the GRF between the two groups (p >0.05). There were no significant difference between the two groups in the spatiotemporal gait parameters (p >0.05). Conclusion: Compared to the slow group, the fast group with cognitive inhibition suppressed muscle activity for unplanned gait termination. The association between SSRT and unplanned gait termination shows that a participant's ability to suppress an incipient finger response is relevant to their ability to construct a corrective gait pattern in a choice-demanding environment.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.923-926
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• 2000

This paper concerned with the patterns of foot-floor contact and electromyography activities of the lower extremity of the body during the termination of human gait. The termination of human gait is defined as the transition from a steady-state gait to a quiet standing posture. The transition between these two states has not been extensively studied and defined. There appears to be a critical period in the gait cycle that the decision to terminate gait or continue to take an additional step must be made.

• 한국운동역학회지
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• 제21권2호
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• pp.189-196
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• 2011

The purpose of this study was to verify the difference in biomechanical variation and pattern of the lower limb between planned and unexpected termination, which is related to the prevention of fatal fall in the elderly. Therefore, selected twenty subjects for each group which composed of females(age: $73.5{\pm}4.63$ year, height: $153.2{\pm}6.46$ cm, body mass: $58.98{\pm}5.82$ kg) and women(age: $23.4{\pm}2.5$ year, height: $164.65{\pm}3.9$ cm, body mass: $58.47{\pm}5.53$ kg) in their twenties. As a result, lower limb's extension moment and power were increased significantly in statistics(p<.05). Also, knee joint power showed instant changes from concentric contraction to eccentric contraction and hip joint power from eccentric contraction to concentric contraction. During unexpected termination there were dramatical increase in eccentric contraction and power(p<.05). In both planned and unexpected termination, ankle joint moment were higher in young group, but the moment of the hip joint were higher in the elderly group(p<.05). In contrast to younger group, there were no changes in knee extension moment in elderly group(p<.05). but showed relatively higher hip joint extension moment and power(p<.05).

• 한국전문물리치료학회지
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• 제10권4호
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• pp.43-59
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• 2003

보행 종료(gait termination)는 인간의 보행개시(gait initiation)나 율동성 보행(rhythmical walking)에 비해 관심을 적게 받고 있다. 파킨슨 환자들이 보행종료와 방향전환 시 가지는 어려움은 이들 환자들이 보행 시 넘어지게 되는 노출 요인으로 보고되어져 왔다. 보행종료에 대한 기전의 이해는 효과적으로 걸음을 멈추지 못해 넘어지게 되는 위험요인을 가진 사람들에게 적용되어질 수 있다. 이 논문에서 우리는 보행종료에 대한 최근문헌을 고찰하고 우리 실험실에서 진행되어온 파킨슨환자의 보행종료에 관한 일련의 실험들의 결과를 요약하였다. 본 연구는 율동적인 보행상태에서 완전한 멈춤으로의 전환에서 일어나는 동역학의 변화를 검사하기위해 시행되었다. 보행속도가 증가함에 따라 따르는 다리(trailing limb; 보행종료시점에서 뒤에 위치하는 다리)의 유의한 가속력 감소가 나타나고 멈출 때 이끄는 다리(leading limb; 보행종료시점에서 앞에 위치한 다리)에서 유의한 감속력의 증가가 나타난다. 보행종료 시, 이끄는 다리의 뒤쪽에 질량중심(center of mass) 을 유지시키기 위해 하지 신전근의 활성도가 오래 지속되어져야 한다. 예측하지 못한 상황에서 보행종료 시, 보행 중이나 예측되어진 상황에서 멈출 때보다 이끄는 다리 아래에서 감속력이 빠르게 발생하는 경향을 보였다. 대상자들을 보행속도에 따라 두 군으로 나눌 때, 계획되지 않은 보행종료를 하는 동안 보행속도가 느린 군이 빠른 군보다 전방 가속력을 급속하게 증가시키는 것으로 나타났다. 이러한 결과들은 보행속도가 느린 대상자들이 따르는 다리로 힘을 생성하기 보다는 주로 이끄는 다리에 의존하여 보행종료를 하는 것을 보여준다. 따르는 다리에서 발생되는 힘과 근육활성도의 조절을 측정하기 위하여, 파킨슨 환자와 연령에 의해 짝짓기된 정상 환자군에게 표적 조건(target condition)을 추가하였다. 파킨슨 환자군은 표적에 다리를 정확히 놓기 위해 몇 발자국 전부터 보행 속도를 줄였다. 파킨슨 환자들은 보행종료를 촉진하기 위해 필요한 근육들의 활성도를 증가시키는데 큰 어려움을 가지고 있다고 생각되어진다.

• The Journal of Korean Physical Therapy
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• 제26권3호
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• pp.216-219
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• 2014

Purpose: We presented with a patient with traumatic brain injury who showed a transcallosal ipsilateral motor pathway from unaffected motor cortex to affected extremities, as evaluated by diffusion tensor tractography (DTT). Methods: One patient and six age-matched normal subjects were enrolled. A 42-year-old left hemiparetic male who suffered from brain injury by motor vehicle accident 9 years ago showed a leukomalactic lesion in the right corona radiata and parieto-temporal lobe. His left extremities were completely paralyzed initially, but recovered slowly over 2 years. At the time of the evaluation, he was able to grasp and release an object, and to walk with spastic gait pattern. DTT was performed using 1.5 T with a Synergy-L Sensitivity Encoding head coil. DTT was obtained with termination criteria of FA <0.2 and an angle change > $45^{\circ}c$. Results: The motor tracts of the unaffected (left) hemisphere of the patient and control subjects originated from the motor cortex and descended along the known corticospinal tract without any transcallosal tract. By contrast, the tract of the affected (right) hemisphere originated from the left premotor cortex, descended through the left corona radiata, and then crossed the mid-portion of the corpus callosum. The tract then descended through the known corticospinal tract pathway to the right medulla. Conclusion: We conclude that the transcallosal ipsilateral motor pathway from the unaffected hemisphere appeared to contribute to the motor recovery in this patient.