Holbein M A, Redfern M S
University of Pittsburgh, Department of Industrial Engineering, PA 15261, USA.
Int J Ind Ergon. 1997 May;19(5):387-95. doi: 10.1016/s0169-8141(96)00023-6.
Stability of the body during manual material handling is an important issue in the prevention of falls and over-exertion injuries. This research investigated stability limits while standing and holding loads in different positions relative to the body. Theoretically, the stability region is the full base of support defined by the perimeter of the foot contact area. However, the functional stability region may be smaller. The purpose of this study was to locate functional stability limits with respect to the base of support. Fifteen male subjects leaned as far as possible in four directions in the sagittal and frontal planes. Their center of gravity location at these extremes determined the stability limit. The results showed that functional stability limits reached only about 60% of the distance to the maximum base of support limits under the conditions of this study. The sway angles reached at the stability limits averaged 9.2 degrees anteroposteriorly and 15.3 degrees laterally. External load positions which lowered the center of gravity of the body-and-load system extended those stability limits. This study provides a postural stability perspective of load-holding which may be applied in establishing safe lifting and reach limits.
在人工搬运物料过程中，身体的稳定性是预防跌倒和过度劳累损伤的一个重要问题。本研究调查了在站立并相对于身体处于不同位置握持负载时的稳定性极限。从理论上讲，稳定区域是由足部接触区域周边所界定的整个支撑面。然而，功能稳定区域可能较小。本研究的目的是确定相对于支撑面的功能稳定性极限。15名男性受试者在矢状面和额状面的四个方向上尽可能地倾斜。他们在这些极限位置时的重心位置确定了稳定性极限。结果表明，在本研究条件下，功能稳定性极限仅达到最大支撑面极限距离的约60%。在稳定性极限处达到的摇摆角度平均前后为9.2度，横向为15.3度。降低身体与负载系统重心的外部负载位置扩展了这些稳定性极限。本研究提供了一个负载握持的姿势稳定性视角，可应用于确定安全的 lifting 和伸展极限（此处lifting 可能是“搬运”之意，原文表述不太准确）。
