Abstract
The stoop, squat and free style lifting techniques were compared with respect to different kinetic and kinematic variables. Displacements and accelerations of the ankle, knee and trunk; torques at the L5-S1 level and knee; EMG of the lumbar paraspinals and quadriceps; area of sway and time to complete the lift were the variables studied. The effect of load weight and load position was also studied. A repeated measures design of experiment was adopted. Results show that there are significant differences between the three techniques. Each one of the lifting methods minimizes on a different set of variables. Load weight and position also have a significant effect on several of the parameters that were studied. A table was constructed to provide a comparison between the three techniques (with the two load weights and load positions) based on the parameters that were investigated. It was concluded that while it is possible to select a technique that would minimize on a particular criterion, it is not fully justified to select a technique that is considered a "safe lifting technique" for all people and all configurations of loading on all joints of the body.