High-resolution videoradiography was used to collect data onforelimb kinematics and on the position of the forepaw relativeto a reference point on the head at the moment of touchdown(Fig. 1B; see also supplementary video files I–VI). The X-ray systemused (Neurostar, Siemens AG, Erlangen, Germany) operates withhigh-speed cameras (SpeedCam Visario G2; Weinberger GmbH,Erlangen, Germany). For our purposes a frame frequency of 300 Hzand a spatial resolution of 1536 dpi × 1024 dpi were used.