Knee cartilage surface loading during stationary bi cycling

Bicycling, either stationary or in the open air, is a common leisure activity. It is known, that this e xercise is characterized by relatively low knee loading, thus it is often advis ed even to elderly people as a recreational activit y. However, the knowledge about knee cartilage load distribution during bicycling i s limited. The presented method utilizes experiment al measurements of forces developed between feet and pedals as well as motion capture of the activity, as an input for a three-d imensional rigid body simulation. The aim of the multibody simulation is to acquire knee forces and angles during stationary bicycling. For this exercise, a human lower body model was created. The model consisted of two feet, two tibias, two femurs and pelvis sections connected via kinematical joints. Lower body muscles were describ ed as 32 PID servo muscles. The results of the mult ibody simulation were transferred to the detailed finite element model of the knee. The FE analysis allowed estimating the c artilage surface loading during stationary cycling activity. The results were compa red with different studies, presenting benefits and limitations of the proposed method. The results can be utilized in optimization of the rider position, crank mechanism as well as in the prosthesis design.