The surface of a running track (i.e. cinder or rubber) has an effect on a runner's performance. I would like to get some device for measuring how much energy a runner loses on each surfaces. I've tried to rig up a system with a ball and measuring how high it bounces on both surfaces, but this hasn't worked out well.
Is there a device I could get that I get which would measure how much energy is lost when a body strikes a surface which would work on a cinder and rubberized surface?