The objective of this chapter is to understand the biomechanics of rock climbing based on the forces applied at each support. The mechanical principles of rock climbing biomechanics are presented frst and adapted with different climbing devices used to measure the contact forces. A computational method is presented to overcome the need for a climbing device equipped with three dimensional (3D) force sensors. A simulation method of 3D climbing movements is developed. The frst part of this chapter describes the role of limbs in postural regulation during climbing. Notably, supporting forces depend on the posture of the climber, the number of supports and the climbing wall inclination. We discuss the transition between static postures and movement with dynamic motion of the limbs. The second part of the chapter focuses on the kinematics of rock climbing and introduces a modelling technique for estimating the support forces thanks to motion capture analysis.