On day 1, allow the mouse to acclimate to the treadmill apparatus for 30 min. They will attempt frequent postural adjustments and the hindlimbs may slip off the side of the treadmill. If so, use your hands to gently reposition the mouse back onto the center of the treadmill. Some mice may continue to do this over the first couple of sessions, but it will diminish over time. Over the course of the 30 minutes, mice will calm down and may or may not attempt to ambulate on the treadmill.