 Pain: Visual Analogue Scale Gait test: 8 sensors will be attached to the legs and lower back using comfortable straps and will be asked to walk 20 meters on a flat surface, two times. A third 20 meter walk will be performed with an additional distractive cognitive task counting -1. The 4th test will be fast walking. Walking performance e.g., speed, cadence, and stability and spatio-temporal parameters of gait e.g., velocity, stride time, gait inter-cycle variability, double support, and gait initiation will be measured. 