들기 작업할 때 자세의 변화에 따른 악력과 지면 반발력의 상관관계

Abstract

ABSTRACT The purpose of this study, during the lifting task was researching the difference and a relationship between the ground reaction force and the grip strength by change of position. After grip strength has measured in symmetry position and asymmetry position at 45cm and 75cm of height of hand, ground reaction force was measured by same attitude lifting wooden box. We analyzed the difference of grip strength and ground reaction force in each position change. The results of grip strength, the grip strength of both hand were significant difference that in study subject symmetry and asymmetry position ( p <0.01). The results of symmetry lifting task, the study subjects was significant difference of the ground reaction force difference by height ( p <0.05). Asymmetry lifting task was significant difference of ground reaction force difference by direction of rotation was changed ( p <0.01). The result of it will rotate with non-dominant hand side of lifting tasks from height 75cm where it easily maintains a balance possibility and decreasing the load of the hand. Therefore, from the workshop in the work people, it will be between the height 75cm and non-dominant hand side of trunk rotatory direction in the lifting tasks. Future study is necessary researched about the change of grip strength when the height of the hand is higher, and the difference of the ground r eaction force when the change of weight. Keyword: Manual materials handling, Symmetric lifting, Asymmetric lifting, Grip strength, Ground reaction force