The Vicon optical motion-capture system (Vicon Motion Systems Ltd., Oxfordshire, United Kingdom) provides precise three-dimensional measurement of human movement using multiple infrared cameras and reflective markers placed on anatomical landmarks. The system can calculate body-segment positions, joint angles, velocities, accelerations, and other kinematic outcomes and can be synchronized with EMG, force plates, EEG, fNIRS, and exoskeleton systems. It is suitable for gait analysis, occupational biomechanics, ergonomics, rehabilitation, sports performance, material-handling studies, injury prevention, and validation of wearable motion sensors and musculoskeletal models.