Optimum handle positions in a hox-holding task

Ten combinations of handle position, four symmetric and six asymmetric, were tested in a static holding task. Ten male subjects held each of 10 boxes (two weights x five sizes) at waist level with each handle position. Biomechanical, physiological and psychophysical measures were taken. Handle position was highly significant for all measures, but handle position effects varied depending upon the measure used. Two groups of effects were found, one biomechanical and the other physiological and psychophysical with little intercorrelation between the groups. The interface between the body and the container emerged as an important part of the holding task with friction and reaction forces comparable to the box weight. In general, the best handle combinations on all measures were those which combined strong horizontal and vertical stabilizing components.