We have two systems to track motion. A digital 2D system that is used to measure planar movements in the reaching setup and samples at 100 Hz, and a high resolution 3D system that allows measuring kinematics in synch with digital video and other physiological measurements through an infrared system. Sampling rate goes up to 400 Hz for the infrared cameras and to 100 Hz for the digital video cameras. Through this system we are able to track both gross and fine movements such as those involved in gait, precision grasping, piano playing and even facial emotions. This system can be used together with EMG to capture simultaneously kinematics and dynamics aspects of an action.