The effects of initial lifting height, load magnitude, and lifting speed on the peak dynamic L5/S1 moments

• Published in: International journal of industrial ergonomics 2003, Vol.31 (1), p.51-59
• Main Authors: Lavender, Steven A., Andersson, Gunnar B.J., Schipplein, Owen D., Fuentes, Henry J.
• Format: Article
• Language: English
• Subjects: LBD; Lifting; Linked segment models; Moments; NIOSH lifting equation; Spine
• ISSN: 0169-8141; 1872-8219
• DOI: 10.1016/S0169-8141(02)00174-9

The purpose of this study was to quantify the peak dynamic bending moments on the spine during sagittal plane lifting as a function of the load's initial height above the floor, the load's magnitude, and the lifting speed. Ten male subjects participated in a repeated measures experiment in which 24 lifts were performed. The boxes lifted by the subjects contained loads that were 20, 100, 200, and 300 N. The lifts originated from three vertical locations (7.5 cm or “floor” level, knee level, and knuckle level), and were lifted at two qualitatively defined lifting speeds (“normal” and “fast”). All lifts were symmetric about the body's mid-sagittal plane and the boxes were gripped with both hands using the handles. Kinetic and kinematic data were used in a “bottom-up” linked segment dynamic model to determine the peak sagittal bending moment experienced by the subjects during each lift. The peak moments were significantly greater when lifting from lower lift heights ( p