The effect of the load's center of gravity (CoG) on manual materials handling tasks received little attention in literature. The motivation of this study was to examine the effects of handle height, load's CoG height and load on lifting tasks. Eighteen participants performed 27 lifting tasks, including 3 handle heights (10, 30, 50 cm) by 3 load's CoG heights (10, 30, 50 cm) by 3 loads (7, 14, 21 kg). The lifting time, maximum box tilt angle, muscular activity (brachioradialis, biceps brachii, deltoid, and erector spinae), maximum CoP velocity, and lifting difficulty were measured. The results showed that lifting time and maximum box tilt angle decreased with increasing handle height. Middle handle height (30 cm) resulted in the lowest muscular activity, maximum CoP velocity, and lifting difficulty. Low load's CoG height decreased lifting time, maximum box tilt angle, muscular activity, and lifting difficulty, however, it also increased maximum CoP velocity. In addition, high load increased lifting time, maximum box tilt angle, muscular activity, maximum CoP velocity, and lifting difficulty.

负载重心（CoG）对手动物料处理任务的影响在文献中很少受到关注。这项研究的目的是研究手柄高度，负载的CoG高度和负载对提升任务的影响。18位参与者执行了27次举升任务，包括3个手柄高度（10、30、50厘米）乘3个负载的CoG高度（10、30、50厘米）乘3个负载（7、14、21公斤）。测量了举升时间，最大框倾斜角，肌肉活动（臂radi，肱二头肌，三角肌和竖脊肌），最大CoP速度和举升难度。结果表明，提升时间和最大箱体倾斜角随手柄高度的增加而减小。中部手柄高度（30厘米）导致最低的肌肉活动，最大的CoP速度和提举难度。低负载” CoG的高度降低了举升时间，最大的箱子倾斜角度，肌肉活动和举升难度，但是，它也增加了最大的CoP速度。此外，高负荷会增加举升时间，最大的举重箱倾斜角度，肌肉活动，最大的CoP速度和举升难度。