Effect of seat inclination on intradiscal pressure during simulateddriving task, assessed using a biomechanical model

This work aimed to develop a mathematical model to evaluate the effect of seat inclination using as input the biomechanical characteristics of the user. The biomechanical model includes weight, posture, flexion of the pelvis and trunk and 5º and –5º seat inclinations. Using actual data collected during an experiment with 26 participants, a validation process was carried out to measure the model’s ability to correctly predict load values on the ischial tuberosity. The results show a consistent model with an accuracy of 82% and a predictive quality of pred (25) = 0.77. Another outcome of the study is an equation to calculate the intradiscal pressure based on the load at the ischial tuberosity. The biomechanical model and the equations can be used to assess the effects of inclination of the seat and its backrest in chair design processes.