“…The predicted μ values were all above 0.80 (0.81-1.0), 3.05 for load holding close to the chest, 40.9, 10.9, 7.9, and 5.4 for load holding at different heights from 90 to 180 cm indicating that computed muscle forces are much less compatible with recorded EMG for tasks in upright postures. Table 3 Predictions for the global muscle forces (right/left sides), sum of global ( F G ), local lumbar ( F L ) and total muscle forces ( F T ) on both sides, local spinal loads (compression and posterior-anterior shear forces positive in downward and anterior directions, respectively) at the L4-L5 and L5-S1 disc mid-heights, and L4-L5 intradiscal pressure (IDP) values for holding 10 Unstable 20°Stable Unstable Unstable Stable 30°Stable Stable Stable Stable 40°Stable Stable Stable Stable 50°Stable Stable Stable Stable 60°Stable Stable Stable Stable 70°Stable Stable Stable Stable 80°Stable Stable Stable Stable a The smallest eigenvalue of the Hessian matrix is equal to zero (Meta stable), smaller than zero (Unstable), or greater than zero (Stable).…”